(In contrast, implementation of RCU is permitted only in software licensed
under either GPL or LGPL. Sorry!!!)
+In 1987, Rashid et al. described lazy TLB-flush [RichardRashid87a].
+At first glance, this has nothing to do with RCU, but nevertheless
+this paper helped inspire the update-side batching used in the later
+RCU implementation in DYNIX/ptx. In 1988, Barbara Liskov published
+a description of Argus that noted that use of out-of-date values can
+be tolerated in some situations. Thus, this paper provides some early
+theoretical justification for use of stale data.
+
In 1990, Pugh [Pugh90] noted that explicitly tracking which threads
were reading a given data structure permitted deferred free to operate
in the presence of non-terminating threads. However, this explicit
to see how much of the performance advantage reported in 1990 remains
today.
-At about this same time, Adams [Adams91] described ``chaotic relaxation'',
-where the normal barriers between successive iterations of convergent
-numerical algorithms are relaxed, so that iteration $n$ might use
-data from iteration $n-1$ or even $n-2$. This introduces error,
-which typically slows convergence and thus increases the number of
+At about this same time, Andrews [Andrews91textbook] described ``chaotic
+relaxation'', where the normal barriers between successive iterations
+of convergent numerical algorithms are relaxed, so that iteration $n$
+might use data from iteration $n-1$ or even $n-2$. This introduces
+error, which typically slows convergence and thus increases the number of
iterations required. However, this increase is sometimes more than made
up for by a reduction in the number of expensive barrier operations,
which are otherwise required to synchronize the threads at the end
In 1992, Henry (now Alexia) Massalin completed a dissertation advising
parallel programmers to defer processing when feasible to simplify
-synchronization. RCU makes extremely heavy use of this advice.
+synchronization [HMassalinPhD]. RCU makes extremely heavy use of
+this advice.
In 1993, Jacobson [Jacobson93] verbally described what is perhaps the
simplest deferred-free technique: simply waiting a fixed amount of time
systems made pervasive use of RCU in place of "existence locks", which
greatly simplifies locking hierarchies and helps avoid deadlocks.
-2001 saw the first RCU presentation involving Linux [McKenney01a]
-at OLS. The resulting abundance of RCU patches was presented the
-following year [McKenney02a], and use of RCU in dcache was first
-described that same year [Linder02a].
+The year 2000 saw an email exchange that would likely have
+led to yet another independent invention of something like RCU
+[RustyRussell2000a,RustyRussell2000b]. Instead, 2001 saw the first
+RCU presentation involving Linux [McKenney01a] at OLS. The resulting
+abundance of RCU patches was presented the following year [McKenney02a],
+and use of RCU in dcache was first described that same year [Linder02a].
Also in 2002, Michael [Michael02b,Michael02a] presented "hazard-pointer"
techniques that defer the destruction of data structures to simplify
non-blocking synchronization (wait-free synchronization, lock-free
synchronization, and obstruction-free synchronization are all examples of
-non-blocking synchronization). In particular, this technique eliminates
-locking, reduces contention, reduces memory latency for readers, and
-parallelizes pipeline stalls and memory latency for writers. However,
-these techniques still impose significant read-side overhead in the
-form of memory barriers. Researchers at Sun worked along similar lines
-in the same timeframe [HerlihyLM02]. These techniques can be thought
-of as inside-out reference counts, where the count is represented by the
-number of hazard pointers referencing a given data structure rather than
-the more conventional counter field within the data structure itself.
-The key advantage of inside-out reference counts is that they can be
-stored in immortal variables, thus allowing races between access and
-deletion to be avoided.
+non-blocking synchronization). The corresponding journal article appeared
+in 2004 [MagedMichael04a]. This technique eliminates locking, reduces
+contention, reduces memory latency for readers, and parallelizes pipeline
+stalls and memory latency for writers. However, these techniques still
+impose significant read-side overhead in the form of memory barriers.
+Researchers at Sun worked along similar lines in the same timeframe
+[HerlihyLM02]. These techniques can be thought of as inside-out reference
+counts, where the count is represented by the number of hazard pointers
+referencing a given data structure rather than the more conventional
+counter field within the data structure itself. The key advantage
+of inside-out reference counts is that they can be stored in immortal
+variables, thus allowing races between access and deletion to be avoided.
By the same token, RCU can be thought of as a "bulk reference count",
where some form of reference counter covers all reference by a given CPU
In 2003, the K42 group described how RCU could be used to create
hot-pluggable implementations of operating-system functions [Appavoo03a].
-Later that year saw a paper describing an RCU implementation of System
-V IPC [Arcangeli03], and an introduction to RCU in Linux Journal
+Later that year saw a paper describing an RCU implementation
+of System V IPC [Arcangeli03] (following up on a suggestion by
+Hugh Dickins [Dickins02a] and an implementation by Mingming Cao
+[MingmingCao2002IPCRCU]), and an introduction to RCU in Linux Journal
[McKenney03a].
2004 has seen a Linux-Journal article on use of RCU in dcache
}
}
+@phdthesis{HMassalinPhD
+,author="H. Massalin"
+,title="Synthesis: An Efficient Implementation of Fundamental Operating
+System Services"
+,school="Columbia University"
+,address="New York, NY"
+,year="1992"
+,annotation={
+ Mondo optimizing compiler.
+ Wait-free stuff.
+ Good advice: defer work to avoid synchronization. See page 90
+ (PDF page 106), Section 5.4, fourth bullet point.
+}
+}
+
@unpublished{Jacobson93
,author="Van Jacobson"
,title="Avoid Read-Side Locking Via Delayed Free"
[Viewed October 18, 2004]"
}
+@conference{Michael02b
+,author="Maged M. Michael"
+,title="High Performance Dynamic Lock-Free Hash Tables and List-Based Sets"
+,Year="2002"
+,Month="August"
+,booktitle="{Proceedings of the 14\textsuperscript{th} Annual ACM
+Symposium on Parallel
+Algorithms and Architecture}"
+,pages="73-82"
+,annotation={
+Like the title says...
+}
+}
+
@Conference{Linder02a
,Author="Hanna Linder and Dipankar Sarma and Maneesh Soni"
,Title="Scalability of the Directory Entry Cache"
}
}
+@conference{Michael02a
+,author="Maged M. Michael"
+,title="Safe Memory Reclamation for Dynamic Lock-Free Objects Using Atomic
+Reads and Writes"
+,Year="2002"
+,Month="August"
+,booktitle="{Proceedings of the 21\textsuperscript{st} Annual ACM
+Symposium on Principles of Distributed Computing}"
+,pages="21-30"
+,annotation={
+ Each thread keeps an array of pointers to items that it is
+ currently referencing. Sort of an inside-out garbage collection
+ mechanism, but one that requires the accessing code to explicitly
+ state its needs. Also requires read-side memory barriers on
+ most architectures.
+}
+}
+
@unpublished{Dickins02a
,author="Hugh Dickins"
,title="Use RCU for System-V IPC"
,note="private communication"
}
+@InProceedings{HerlihyLM02
+,author={Maurice Herlihy and Victor Luchangco and Mark Moir}
+,title="The Repeat Offender Problem: A Mechanism for Supporting Dynamic-Sized,
+Lock-Free Data Structures"
+,booktitle={Proceedings of 16\textsuperscript{th} International
+Symposium on Distributed Computing}
+,year=2002
+,month="October"
+,pages="339-353"
+}
+
@unpublished{Sarma02b
,Author="Dipankar Sarma"
,Title="Some dcache\_rcu benchmark numbers"
}
}
+@unpublished{MingmingCao2002IPCRCU
+,Author="Mingming Cao"
+,Title="[PATCH]updated ipc lock patch"
+,month="October"
+,year="2002"
+,note="Available:
+\url{https://lkml.org/lkml/2002/10/24/262}
+[Viewed February 15, 2014]"
+,annotation={
+ Mingming Cao's patch to introduce RCU to SysV IPC.
+}
+}
+
@unpublished{LinusTorvalds2003a
,Author="Linus Torvalds"
,Title="Re: {[PATCH]} small fixes in brlock.h"
}
}
+@article{MagedMichael04a
+,author="Maged M. Michael"
+,title="Hazard Pointers: Safe Memory Reclamation for Lock-Free Objects"
+,Year="2004"
+,Month="June"
+,journal="IEEE Transactions on Parallel and Distributed Systems"
+,volume="15"
+,number="6"
+,pages="491-504"
+,url="Available:
+\url{http://www.research.ibm.com/people/m/michael/ieeetpds-2004.pdf}
+[Viewed March 1, 2005]"
+,annotation={
+ New canonical hazard-pointer citation.
+}
+}
+
@phdthesis{PaulEdwardMcKenneyPhD
,author="Paul E. McKenney"
,title="Exploiting Deferred Destruction:
variations on this theme.
b. Limiting update rate. For example, if updates occur only
- once per hour, then no explicit rate limiting is required,
- unless your system is already badly broken. The dcache
- subsystem takes this approach -- updates are guarded
- by a global lock, limiting their rate.
+ once per hour, then no explicit rate limiting is
+ required, unless your system is already badly broken.
+ Older versions of the dcache subsystem take this approach,
+ guarding updates with a global lock, limiting their rate.
c. Trusted update -- if updates can only be done manually by
superuser or some other trusted user, then it might not
the machine.
d. Use call_rcu_bh() rather than call_rcu(), in order to take
- advantage of call_rcu_bh()'s faster grace periods.
+ advantage of call_rcu_bh()'s faster grace periods. (This
+ is only a partial solution, though.)
e. Periodically invoke synchronize_rcu(), permitting a limited
number of updates per grace period.
The same cautions apply to call_rcu_bh(), call_rcu_sched(),
call_srcu(), and kfree_rcu().
+ Note that although these primitives do take action to avoid memory
+ exhaustion when any given CPU has too many callbacks, a determined
+ user could still exhaust memory. This is especially the case
+ if a system with a large number of CPUs has been configured to
+ offload all of its RCU callbacks onto a single CPU, or if the
+ system has relatively little free memory.
+
9. All RCU list-traversal primitives, which include
rcu_dereference(), list_for_each_entry_rcu(), and
list_for_each_safe_rcu(), must be either within an RCU read-side
To reduce its OS jitter, do any of the following:
1. Run your workload at a real-time priority, which will allow
preempting the kworker daemons.
-2. Do any of the following needed to avoid jitter that your
+2. A given workqueue can be made visible in the sysfs filesystem
+ by passing the WQ_SYSFS to that workqueue's alloc_workqueue().
+ Such a workqueue can be confined to a given subset of the
+ CPUs using the /sys/devices/virtual/workqueue/*/cpumask sysfs
+ files. The set of WQ_SYSFS workqueues can be displayed using
+ "ls sys/devices/virtual/workqueue". That said, the workqueues
+ maintainer would like to caution people against indiscriminately
+ sprinkling WQ_SYSFS across all the workqueues. The reason for
+ caution is that it is easy to add WQ_SYSFS, but because sysfs is
+ part of the formal user/kernel API, it can be nearly impossible
+ to remove it, even if its addition was a mistake.
+3. Do any of the following needed to avoid jitter that your
application cannot tolerate:
a. Build your kernel with CONFIG_SLUB=y rather than
CONFIG_SLAB=y, thus avoiding the slab allocator's periodic
b = p; /* BUG: Compiler can reorder!!! */
do_something();
-The solution is again ACCESS_ONCE(), which preserves the ordering between
-the load from variable 'a' and the store to variable 'b':
+The solution is again ACCESS_ONCE() and barrier(), which preserves the
+ordering between the load from variable 'a' and the store to variable 'b':
q = ACCESS_ONCE(a);
if (q) {
+ barrier();
ACCESS_ONCE(b) = p;
do_something();
} else {
+ barrier();
ACCESS_ONCE(b) = p;
do_something_else();
}
-You could also use barrier() to prevent the compiler from moving
-the stores to variable 'b', but barrier() would not prevent the
-compiler from proving to itself that a==1 always, so ACCESS_ONCE()
-is also needed.
+The initial ACCESS_ONCE() is required to prevent the compiler from
+proving the value of 'a', and the pair of barrier() invocations are
+required to prevent the compiler from pulling the two identical stores
+to 'b' out from the legs of the "if" statement.
It is important to note that control dependencies absolutely require a
a conditional. For example, the following "optimized" version of
-the above example breaks ordering:
+the above example breaks ordering, which is why the barrier() invocations
+are absolutely required if you have identical stores in both legs of
+the "if" statement:
q = ACCESS_ONCE(a);
ACCESS_ONCE(b) = p; /* BUG: No ordering vs. load from a!!! */
for example, as follows:
if (ACCESS_ONCE(a) > 0) {
+ barrier();
ACCESS_ONCE(b) = q / 2;
do_something();
} else {
+ barrier();
ACCESS_ONCE(b) = q / 3;
do_something_else();
}
q = ACCESS_ONCE(a);
if (q % MAX) {
+ barrier();
ACCESS_ONCE(b) = p;
do_something();
} else {
+ barrier();
ACCESS_ONCE(b) = p;
do_something_else();
}
use smb_rmb(), smp_wmb(), or, in the case of prior stores and
later loads, smp_mb().
+ (*) If both legs of the "if" statement begin with identical stores
+ to the same variable, a barrier() statement is required at the
+ beginning of each leg of the "if" statement.
+
(*) Control dependencies require at least one run-time conditional
- between the prior load and the subsequent store. If the compiler
+ between the prior load and the subsequent store, and this
+ conditional must involve the prior load. If the compiler
is able to optimize the conditional away, it will have also
optimized away the ordering. Careful use of ACCESS_ONCE() can
help to preserve the needed conditional.
while perfectly safe in single-threaded code, can be fatal in concurrent
code. Here are some examples of these sorts of optimizations:
+ (*) The compiler is within its rights to reorder loads and stores
+ to the same variable, and in some cases, the CPU is within its
+ rights to reorder loads to the same variable. This means that
+ the following code:
+
+ a[0] = x;
+ a[1] = x;
+
+ Might result in an older value of x stored in a[1] than in a[0].
+ Prevent both the compiler and the CPU from doing this as follows:
+
+ a[0] = ACCESS_ONCE(x);
+ a[1] = ACCESS_ONCE(x);
+
+ In short, ACCESS_ONCE() provides cache coherence for accesses from
+ multiple CPUs to a single variable.
+
(*) The compiler is within its rights to merge successive loads from
the same variable. Such merging can cause the compiler to "optimize"
the following code:
Memory operations issued after the ACQUIRE will be completed after the
ACQUIRE operation has completed.
- Memory operations issued before the ACQUIRE may be completed after the
- ACQUIRE operation has completed. An smp_mb__before_spinlock(), combined
- with a following ACQUIRE, orders prior loads against subsequent stores and
- stores and prior stores against subsequent stores. Note that this is
- weaker than smp_mb()! The smp_mb__before_spinlock() primitive is free on
- many architectures.
+ Memory operations issued before the ACQUIRE may be completed after
+ the ACQUIRE operation has completed. An smp_mb__before_spinlock(),
+ combined with a following ACQUIRE, orders prior loads against
+ subsequent loads and stores and also orders prior stores against
+ subsequent stores. Note that this is weaker than smp_mb()! The
+ smp_mb__before_spinlock() primitive is free on many architectures.
(2) RELEASE operation implication:
ACQUIRE M, STORE *B, STORE *A, RELEASE M
-This same reordering can of course occur if the lock's ACQUIRE and RELEASE are
-to the same lock variable, but only from the perspective of another CPU not
-holding that lock.
-
-In short, a RELEASE followed by an ACQUIRE may -not- be assumed to be a full
-memory barrier because it is possible for a preceding RELEASE to pass a
-later ACQUIRE from the viewpoint of the CPU, but not from the viewpoint
-of the compiler. Note that deadlocks cannot be introduced by this
-interchange because if such a deadlock threatened, the RELEASE would
-simply complete.
-
-If it is necessary for a RELEASE-ACQUIRE pair to produce a full barrier, the
-ACQUIRE can be followed by an smp_mb__after_unlock_lock() invocation. This
-will produce a full barrier if either (a) the RELEASE and the ACQUIRE are
-executed by the same CPU or task, or (b) the RELEASE and ACQUIRE act on the
-same variable. The smp_mb__after_unlock_lock() primitive is free on many
-architectures. Without smp_mb__after_unlock_lock(), the critical sections
-corresponding to the RELEASE and the ACQUIRE can cross:
+When the ACQUIRE and RELEASE are a lock acquisition and release,
+respectively, this same reordering can occur if the lock's ACQUIRE and
+RELEASE are to the same lock variable, but only from the perspective of
+another CPU not holding that lock. In short, a ACQUIRE followed by an
+RELEASE may -not- be assumed to be a full memory barrier.
+
+Similarly, the reverse case of a RELEASE followed by an ACQUIRE does not
+imply a full memory barrier. If it is necessary for a RELEASE-ACQUIRE
+pair to produce a full barrier, the ACQUIRE can be followed by an
+smp_mb__after_unlock_lock() invocation. This will produce a full barrier
+if either (a) the RELEASE and the ACQUIRE are executed by the same
+CPU or task, or (b) the RELEASE and ACQUIRE act on the same variable.
+The smp_mb__after_unlock_lock() primitive is free on many architectures.
+Without smp_mb__after_unlock_lock(), the CPU's execution of the critical
+sections corresponding to the RELEASE and the ACQUIRE can cross, so that:
*A = a;
RELEASE M
ACQUIRE N, STORE *B, STORE *A, RELEASE M
-With smp_mb__after_unlock_lock(), they cannot, so that:
+It might appear that this reordering could introduce a deadlock.
+However, this cannot happen because if such a deadlock threatened,
+the RELEASE would simply complete, thereby avoiding the deadlock.
+
+ Why does this work?
+
+ One key point is that we are only talking about the CPU doing
+ the reordering, not the compiler. If the compiler (or, for
+ that matter, the developer) switched the operations, deadlock
+ -could- occur.
+
+ But suppose the CPU reordered the operations. In this case,
+ the unlock precedes the lock in the assembly code. The CPU
+ simply elected to try executing the later lock operation first.
+ If there is a deadlock, this lock operation will simply spin (or
+ try to sleep, but more on that later). The CPU will eventually
+ execute the unlock operation (which preceded the lock operation
+ in the assembly code), which will unravel the potential deadlock,
+ allowing the lock operation to succeed.
+
+ But what if the lock is a sleeplock? In that case, the code will
+ try to enter the scheduler, where it will eventually encounter
+ a memory barrier, which will force the earlier unlock operation
+ to complete, again unraveling the deadlock. There might be
+ a sleep-unlock race, but the locking primitive needs to resolve
+ such races properly in any case.
+
+With smp_mb__after_unlock_lock(), the two critical sections cannot overlap.
+For example, with the following code, the store to *A will always be
+seen by other CPUs before the store to *B:
*A = a;
RELEASE M
smp_mb__after_unlock_lock();
*B = b;
-will always occur as either of the following:
+The operations will always occur in one of the following orders:
- STORE *A, RELEASE, ACQUIRE, STORE *B
- STORE *A, ACQUIRE, RELEASE, STORE *B
+ STORE *A, RELEASE, ACQUIRE, smp_mb__after_unlock_lock(), STORE *B
+ STORE *A, ACQUIRE, RELEASE, smp_mb__after_unlock_lock(), STORE *B
+ ACQUIRE, STORE *A, RELEASE, smp_mb__after_unlock_lock(), STORE *B
If the RELEASE and ACQUIRE were instead both operating on the same lock
-variable, only the first of these two alternatives can occur.
+variable, only the first of these alternatives can occur. In addition,
+the more strongly ordered systems may rule out some of the above orders.
+But in any case, as noted earlier, the smp_mb__after_unlock_lock()
+ensures that the store to *A will always be seen as happening before
+the store to *B.
Locks and semaphores may not provide any guarantee of ordering on UP compiled
systems, and so cannot be counted on in such a situation to actually achieve
combination of elements combined or discarded, provided the program's view of
the world remains consistent. Note that ACCESS_ONCE() is -not- optional
in the above example, as there are architectures where a given CPU might
-interchange successive loads to the same location. On such architectures,
+reorder successive loads to the same location. On such architectures,
ACCESS_ONCE() does whatever is necessary to prevent this, for example, on
Itanium the volatile casts used by ACCESS_ONCE() cause GCC to emit the
special ld.acq and st.rel instructions that prevent such reordering.
error = fd;
#if 1
/* Sanity check */
- if (rcu_dereference_raw(fdt->fd[fd]) != NULL) {
+ if (rcu_access_pointer(fdt->fd[fd]) != NULL) {
printk(KERN_WARNING "alloc_fd: slot %d not NULL!\n", fd);
rcu_assign_pointer(fdt->fd[fd], NULL);
}
* primitives such as list_add_rcu() as long as it's guarded by rcu_read_lock().
*/
#define list_entry_rcu(ptr, type, member) \
- ({typeof (*ptr) __rcu *__ptr = (typeof (*ptr) __rcu __force *)ptr; \
- container_of((typeof(ptr))rcu_dereference_raw(__ptr), type, member); \
- })
+({ \
+ typeof(*ptr) __rcu *__ptr = (typeof(*ptr) __rcu __force *)ptr; \
+ container_of((typeof(ptr))rcu_dereference_raw(__ptr), type, member); \
+})
/**
* Where are list_empty_rcu() and list_first_entry_rcu()?
* primitives such as list_add_rcu() as long as it's guarded by rcu_read_lock().
*/
#define list_first_or_null_rcu(ptr, type, member) \
- ({struct list_head *__ptr = (ptr); \
- struct list_head *__next = ACCESS_ONCE(__ptr->next); \
- likely(__ptr != __next) ? \
- list_entry_rcu(__next, type, member) : NULL; \
- })
+({ \
+ struct list_head *__ptr = (ptr); \
+ struct list_head *__next = ACCESS_ONCE(__ptr->next); \
+ likely(__ptr != __next) ? list_entry_rcu(__next, type, member) : NULL; \
+})
/**
* list_for_each_entry_rcu - iterate over rcu list of given type
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
*
* Copyright IBM Corporation, 2001
*
#include <linux/debugobjects.h>
#include <linux/bug.h>
#include <linux/compiler.h>
+#include <asm/barrier.h>
+extern int rcu_expedited; /* for sysctl */
#ifdef CONFIG_RCU_TORTURE_TEST
extern int rcutorture_runnable; /* for sysctl */
#endif /* #ifdef CONFIG_RCU_TORTURE_TEST */
do { \
rcu_preempt_sleep_check(); \
rcu_lockdep_assert(!lock_is_held(&rcu_bh_lock_map), \
- "Illegal context switch in RCU-bh" \
- " read-side critical section"); \
+ "Illegal context switch in RCU-bh read-side critical section"); \
rcu_lockdep_assert(!lock_is_held(&rcu_sched_lock_map), \
- "Illegal context switch in RCU-sched"\
- " read-side critical section"); \
+ "Illegal context switch in RCU-sched read-side critical section"); \
} while (0)
#else /* #ifdef CONFIG_PROVE_RCU */
#endif /* #else #ifdef __CHECKER__ */
#define __rcu_access_pointer(p, space) \
- ({ \
- typeof(*p) *_________p1 = (typeof(*p)*__force )ACCESS_ONCE(p); \
- rcu_dereference_sparse(p, space); \
- ((typeof(*p) __force __kernel *)(_________p1)); \
- })
+({ \
+ typeof(*p) *_________p1 = (typeof(*p) *__force)ACCESS_ONCE(p); \
+ rcu_dereference_sparse(p, space); \
+ ((typeof(*p) __force __kernel *)(_________p1)); \
+})
#define __rcu_dereference_check(p, c, space) \
- ({ \
- typeof(*p) *_________p1 = (typeof(*p)*__force )ACCESS_ONCE(p); \
- rcu_lockdep_assert(c, "suspicious rcu_dereference_check()" \
- " usage"); \
- rcu_dereference_sparse(p, space); \
- smp_read_barrier_depends(); \
- ((typeof(*p) __force __kernel *)(_________p1)); \
- })
+({ \
+ typeof(*p) *_________p1 = (typeof(*p) *__force)ACCESS_ONCE(p); \
+ rcu_lockdep_assert(c, "suspicious rcu_dereference_check() usage"); \
+ rcu_dereference_sparse(p, space); \
+ smp_read_barrier_depends(); /* Dependency order vs. p above. */ \
+ ((typeof(*p) __force __kernel *)(_________p1)); \
+})
#define __rcu_dereference_protected(p, c, space) \
- ({ \
- rcu_lockdep_assert(c, "suspicious rcu_dereference_protected()" \
- " usage"); \
- rcu_dereference_sparse(p, space); \
- ((typeof(*p) __force __kernel *)(p)); \
- })
+({ \
+ rcu_lockdep_assert(c, "suspicious rcu_dereference_protected() usage"); \
+ rcu_dereference_sparse(p, space); \
+ ((typeof(*p) __force __kernel *)(p)); \
+})
#define __rcu_access_index(p, space) \
- ({ \
- typeof(p) _________p1 = ACCESS_ONCE(p); \
- rcu_dereference_sparse(p, space); \
- (_________p1); \
- })
+({ \
+ typeof(p) _________p1 = ACCESS_ONCE(p); \
+ rcu_dereference_sparse(p, space); \
+ (_________p1); \
+})
#define __rcu_dereference_index_check(p, c) \
- ({ \
- typeof(p) _________p1 = ACCESS_ONCE(p); \
- rcu_lockdep_assert(c, \
- "suspicious rcu_dereference_index_check()" \
- " usage"); \
- smp_read_barrier_depends(); \
- (_________p1); \
- })
+({ \
+ typeof(p) _________p1 = ACCESS_ONCE(p); \
+ rcu_lockdep_assert(c, \
+ "suspicious rcu_dereference_index_check() usage"); \
+ smp_read_barrier_depends(); /* Dependency order vs. p above. */ \
+ (_________p1); \
+})
/**
* RCU_INITIALIZER() - statically initialize an RCU-protected global variable
* please be careful when making changes to rcu_assign_pointer() and the
* other macros that it invokes.
*/
-#define rcu_assign_pointer(p, v) \
- do { \
- smp_wmb(); \
- ACCESS_ONCE(p) = RCU_INITIALIZER(v); \
- } while (0)
-
+#define rcu_assign_pointer(p, v) smp_store_release(&p, RCU_INITIALIZER(v))
/**
* rcu_access_pointer() - fetch RCU pointer with no dereferencing
#define kfree_rcu(ptr, rcu_head) \
__kfree_rcu(&((ptr)->rcu_head), offsetof(typeof(*(ptr)), rcu_head))
-#ifdef CONFIG_RCU_NOCB_CPU
+#if defined(CONFIG_TINY_RCU) || defined(CONFIG_RCU_NOCB_CPU_ALL)
+static inline int rcu_needs_cpu(int cpu, unsigned long *delta_jiffies)
+{
+ *delta_jiffies = ULONG_MAX;
+ return 0;
+}
+#endif /* #if defined(CONFIG_TINY_RCU) || defined(CONFIG_RCU_NOCB_CPU_ALL) */
+
+#if defined(CONFIG_RCU_NOCB_CPU_ALL)
+static inline bool rcu_is_nocb_cpu(int cpu) { return true; }
+#elif defined(CONFIG_RCU_NOCB_CPU)
bool rcu_is_nocb_cpu(int cpu);
#else
static inline bool rcu_is_nocb_cpu(int cpu) { return false; }
-#endif /* #else #ifdef CONFIG_RCU_NOCB_CPU */
+#endif
/* Only for use by adaptive-ticks code. */
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
*
* Copyright IBM Corporation, 2008
*
#include <linux/cache.h>
+static inline unsigned long get_state_synchronize_rcu(void)
+{
+ return 0;
+}
+
+static inline void cond_synchronize_rcu(unsigned long oldstate)
+{
+ might_sleep();
+}
+
static inline void rcu_barrier_bh(void)
{
wait_rcu_gp(call_rcu_bh);
call_rcu(head, func);
}
-static inline int rcu_needs_cpu(int cpu, unsigned long *delta_jiffies)
-{
- *delta_jiffies = ULONG_MAX;
- return 0;
-}
-
static inline void rcu_note_context_switch(int cpu)
{
rcu_sched_qs(cpu);
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
*
* Copyright IBM Corporation, 2008
*
#define __LINUX_RCUTREE_H
void rcu_note_context_switch(int cpu);
+#ifndef CONFIG_RCU_NOCB_CPU_ALL
int rcu_needs_cpu(int cpu, unsigned long *delta_jiffies);
+#endif /* #ifndef CONFIG_RCU_NOCB_CPU_ALL */
void rcu_cpu_stall_reset(void);
/*
void rcu_barrier(void);
void rcu_barrier_bh(void);
void rcu_barrier_sched(void);
+unsigned long get_state_synchronize_rcu(void);
+void cond_synchronize_rcu(unsigned long oldstate);
extern unsigned long rcutorture_testseq;
extern unsigned long rcutorture_vernum;
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
*
* Copyright (C) IBM Corporation, 2006
* Copyright (C) Fujitsu, 2012
--- /dev/null
+/*
+ * Common functions for in-kernel torture tests.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
+ *
+ * Copyright IBM Corporation, 2014
+ *
+ * Author: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
+ */
+
+#ifndef __LINUX_TORTURE_H
+#define __LINUX_TORTURE_H
+
+#include <linux/types.h>
+#include <linux/cache.h>
+#include <linux/spinlock.h>
+#include <linux/threads.h>
+#include <linux/cpumask.h>
+#include <linux/seqlock.h>
+#include <linux/lockdep.h>
+#include <linux/completion.h>
+#include <linux/debugobjects.h>
+#include <linux/bug.h>
+#include <linux/compiler.h>
+
+/* Definitions for a non-string torture-test module parameter. */
+#define torture_param(type, name, init, msg) \
+ static type name = init; \
+ module_param(name, type, 0444); \
+ MODULE_PARM_DESC(name, msg);
+
+#define TORTURE_FLAG "-torture:"
+#define TOROUT_STRING(s) \
+ pr_alert("%s" TORTURE_FLAG s "\n", torture_type)
+#define VERBOSE_TOROUT_STRING(s) \
+ do { if (verbose) pr_alert("%s" TORTURE_FLAG " %s\n", torture_type, s); } while (0)
+#define VERBOSE_TOROUT_ERRSTRING(s) \
+ do { if (verbose) pr_alert("%s" TORTURE_FLAG "!!! %s\n", torture_type, s); } while (0)
+
+/* Definitions for a non-string torture-test module parameter. */
+#define torture_parm(type, name, init, msg) \
+ static type name = init; \
+ module_param(name, type, 0444); \
+ MODULE_PARM_DESC(name, msg);
+
+/* Definitions for online/offline exerciser. */
+int torture_onoff_init(long ooholdoff, long oointerval);
+char *torture_onoff_stats(char *page);
+bool torture_onoff_failures(void);
+
+/* Low-rider random number generator. */
+struct torture_random_state {
+ unsigned long trs_state;
+ long trs_count;
+};
+#define DEFINE_TORTURE_RANDOM(name) struct torture_random_state name = { 0, 0 }
+unsigned long torture_random(struct torture_random_state *trsp);
+
+/* Task shuffler, which causes CPUs to occasionally go idle. */
+void torture_shuffle_task_register(struct task_struct *tp);
+int torture_shuffle_init(long shuffint);
+
+/* Test auto-shutdown handling. */
+void torture_shutdown_absorb(const char *title);
+int torture_shutdown_init(int ssecs, void (*cleanup)(void));
+
+/* Task stuttering, which forces load/no-load transitions. */
+void stutter_wait(const char *title);
+int torture_stutter_init(int s);
+
+/* Initialization and cleanup. */
+void torture_init_begin(char *ttype, bool v, int *runnable);
+void torture_init_end(void);
+bool torture_cleanup(void);
+bool torture_must_stop(void);
+bool torture_must_stop_irq(void);
+void torture_kthread_stopping(char *title);
+int _torture_create_kthread(int (*fn)(void *arg), void *arg, char *s, char *m,
+ char *f, struct task_struct **tp);
+void _torture_stop_kthread(char *m, struct task_struct **tp);
+
+#define torture_create_kthread(n, arg, tp) \
+ _torture_create_kthread(n, (arg), #n, "Creating " #n " task", \
+ "Failed to create " #n, &(tp))
+#define torture_stop_kthread(n, tp) \
+ _torture_stop_kthread("Stopping " #n " task", &(tp))
+
+#endif /* __LINUX_TORTURE_H */
obj-$(CONFIG_CRASH_DUMP) += crash_dump.o
obj-$(CONFIG_JUMP_LABEL) += jump_label.o
obj-$(CONFIG_CONTEXT_TRACKING) += context_tracking.o
+obj-$(CONFIG_TORTURE_TEST) += torture.o
$(obj)/configs.o: $(obj)/config_data.h
#include <linux/sched.h>
#include <linux/capability.h>
+#include <linux/rcupdate.h> /* rcu_expedited */
+
#define KERNEL_ATTR_RO(_name) \
static struct kobj_attribute _name##_attr = __ATTR_RO(_name)
obj-$(CONFIG_RWSEM_GENERIC_SPINLOCK) += rwsem-spinlock.o
obj-$(CONFIG_RWSEM_XCHGADD_ALGORITHM) += rwsem-xadd.o
obj-$(CONFIG_PERCPU_RWSEM) += percpu-rwsem.o
+obj-$(CONFIG_LOCK_TORTURE_TEST) += locktorture.o
--- /dev/null
+/*
+ * Module-based torture test facility for locking
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
+ *
+ * Copyright (C) IBM Corporation, 2014
+ *
+ * Author: Paul E. McKenney <paulmck@us.ibm.com>
+ * Based on kernel/rcu/torture.c.
+ */
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kthread.h>
+#include <linux/err.h>
+#include <linux/spinlock.h>
+#include <linux/smp.h>
+#include <linux/interrupt.h>
+#include <linux/sched.h>
+#include <linux/atomic.h>
+#include <linux/bitops.h>
+#include <linux/completion.h>
+#include <linux/moduleparam.h>
+#include <linux/percpu.h>
+#include <linux/notifier.h>
+#include <linux/reboot.h>
+#include <linux/freezer.h>
+#include <linux/cpu.h>
+#include <linux/delay.h>
+#include <linux/stat.h>
+#include <linux/slab.h>
+#include <linux/trace_clock.h>
+#include <asm/byteorder.h>
+#include <linux/torture.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com>");
+
+torture_param(int, nwriters_stress, -1,
+ "Number of write-locking stress-test threads");
+torture_param(int, onoff_holdoff, 0, "Time after boot before CPU hotplugs (s)");
+torture_param(int, onoff_interval, 0,
+ "Time between CPU hotplugs (s), 0=disable");
+torture_param(int, shuffle_interval, 3,
+ "Number of jiffies between shuffles, 0=disable");
+torture_param(int, shutdown_secs, 0, "Shutdown time (j), <= zero to disable.");
+torture_param(int, stat_interval, 60,
+ "Number of seconds between stats printk()s");
+torture_param(int, stutter, 5, "Number of jiffies to run/halt test, 0=disable");
+torture_param(bool, verbose, true,
+ "Enable verbose debugging printk()s");
+
+static char *torture_type = "spin_lock";
+module_param(torture_type, charp, 0444);
+MODULE_PARM_DESC(torture_type,
+ "Type of lock to torture (spin_lock, spin_lock_irq, ...)");
+
+static atomic_t n_lock_torture_errors;
+
+static struct task_struct *stats_task;
+static struct task_struct **writer_tasks;
+
+static int nrealwriters_stress;
+static bool lock_is_write_held;
+
+struct lock_writer_stress_stats {
+ long n_write_lock_fail;
+ long n_write_lock_acquired;
+};
+static struct lock_writer_stress_stats *lwsa;
+
+#if defined(MODULE) || defined(CONFIG_LOCK_TORTURE_TEST_RUNNABLE)
+#define LOCKTORTURE_RUNNABLE_INIT 1
+#else
+#define LOCKTORTURE_RUNNABLE_INIT 0
+#endif
+int locktorture_runnable = LOCKTORTURE_RUNNABLE_INIT;
+module_param(locktorture_runnable, int, 0444);
+MODULE_PARM_DESC(locktorture_runnable, "Start locktorture at boot");
+
+/* Forward reference. */
+static void lock_torture_cleanup(void);
+
+/*
+ * Operations vector for selecting different types of tests.
+ */
+struct lock_torture_ops {
+ void (*init)(void);
+ int (*writelock)(void);
+ void (*write_delay)(struct torture_random_state *trsp);
+ void (*writeunlock)(void);
+ unsigned long flags;
+ const char *name;
+};
+
+static struct lock_torture_ops *cur_ops;
+
+/*
+ * Definitions for lock torture testing.
+ */
+
+static int torture_lock_busted_write_lock(void)
+{
+ return 0; /* BUGGY, do not use in real life!!! */
+}
+
+static void torture_lock_busted_write_delay(struct torture_random_state *trsp)
+{
+ const unsigned long longdelay_us = 100;
+
+ /* We want a long delay occasionally to force massive contention. */
+ if (!(torture_random(trsp) %
+ (nrealwriters_stress * 2000 * longdelay_us)))
+ mdelay(longdelay_us);
+#ifdef CONFIG_PREEMPT
+ if (!(torture_random(trsp) % (nrealwriters_stress * 20000)))
+ preempt_schedule(); /* Allow test to be preempted. */
+#endif
+}
+
+static void torture_lock_busted_write_unlock(void)
+{
+ /* BUGGY, do not use in real life!!! */
+}
+
+static struct lock_torture_ops lock_busted_ops = {
+ .writelock = torture_lock_busted_write_lock,
+ .write_delay = torture_lock_busted_write_delay,
+ .writeunlock = torture_lock_busted_write_unlock,
+ .name = "lock_busted"
+};
+
+static DEFINE_SPINLOCK(torture_spinlock);
+
+static int torture_spin_lock_write_lock(void) __acquires(torture_spinlock)
+{
+ spin_lock(&torture_spinlock);
+ return 0;
+}
+
+static void torture_spin_lock_write_delay(struct torture_random_state *trsp)
+{
+ const unsigned long shortdelay_us = 2;
+ const unsigned long longdelay_us = 100;
+
+ /* We want a short delay mostly to emulate likely code, and
+ * we want a long delay occasionally to force massive contention.
+ */
+ if (!(torture_random(trsp) %
+ (nrealwriters_stress * 2000 * longdelay_us)))
+ mdelay(longdelay_us);
+ if (!(torture_random(trsp) %
+ (nrealwriters_stress * 2 * shortdelay_us)))
+ udelay(shortdelay_us);
+#ifdef CONFIG_PREEMPT
+ if (!(torture_random(trsp) % (nrealwriters_stress * 20000)))
+ preempt_schedule(); /* Allow test to be preempted. */
+#endif
+}
+
+static void torture_spin_lock_write_unlock(void) __releases(torture_spinlock)
+{
+ spin_unlock(&torture_spinlock);
+}
+
+static struct lock_torture_ops spin_lock_ops = {
+ .writelock = torture_spin_lock_write_lock,
+ .write_delay = torture_spin_lock_write_delay,
+ .writeunlock = torture_spin_lock_write_unlock,
+ .name = "spin_lock"
+};
+
+static int torture_spin_lock_write_lock_irq(void)
+__acquires(torture_spinlock_irq)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&torture_spinlock, flags);
+ cur_ops->flags = flags;
+ return 0;
+}
+
+static void torture_lock_spin_write_unlock_irq(void)
+__releases(torture_spinlock)
+{
+ spin_unlock_irqrestore(&torture_spinlock, cur_ops->flags);
+}
+
+static struct lock_torture_ops spin_lock_irq_ops = {
+ .writelock = torture_spin_lock_write_lock_irq,
+ .write_delay = torture_spin_lock_write_delay,
+ .writeunlock = torture_lock_spin_write_unlock_irq,
+ .name = "spin_lock_irq"
+};
+
+/*
+ * Lock torture writer kthread. Repeatedly acquires and releases
+ * the lock, checking for duplicate acquisitions.
+ */
+static int lock_torture_writer(void *arg)
+{
+ struct lock_writer_stress_stats *lwsp = arg;
+ static DEFINE_TORTURE_RANDOM(rand);
+
+ VERBOSE_TOROUT_STRING("lock_torture_writer task started");
+ set_user_nice(current, 19);
+
+ do {
+ schedule_timeout_uninterruptible(1);
+ cur_ops->writelock();
+ if (WARN_ON_ONCE(lock_is_write_held))
+ lwsp->n_write_lock_fail++;
+ lock_is_write_held = 1;
+ lwsp->n_write_lock_acquired++;
+ cur_ops->write_delay(&rand);
+ lock_is_write_held = 0;
+ cur_ops->writeunlock();
+ stutter_wait("lock_torture_writer");
+ } while (!torture_must_stop());
+ torture_kthread_stopping("lock_torture_writer");
+ return 0;
+}
+
+/*
+ * Create an lock-torture-statistics message in the specified buffer.
+ */
+static void lock_torture_printk(char *page)
+{
+ bool fail = 0;
+ int i;
+ long max = 0;
+ long min = lwsa[0].n_write_lock_acquired;
+ long long sum = 0;
+
+ for (i = 0; i < nrealwriters_stress; i++) {
+ if (lwsa[i].n_write_lock_fail)
+ fail = true;
+ sum += lwsa[i].n_write_lock_acquired;
+ if (max < lwsa[i].n_write_lock_fail)
+ max = lwsa[i].n_write_lock_fail;
+ if (min > lwsa[i].n_write_lock_fail)
+ min = lwsa[i].n_write_lock_fail;
+ }
+ page += sprintf(page, "%s%s ", torture_type, TORTURE_FLAG);
+ page += sprintf(page,
+ "Writes: Total: %lld Max/Min: %ld/%ld %s Fail: %d %s\n",
+ sum, max, min, max / 2 > min ? "???" : "",
+ fail, fail ? "!!!" : "");
+ if (fail)
+ atomic_inc(&n_lock_torture_errors);
+}
+
+/*
+ * Print torture statistics. Caller must ensure that there is only one
+ * call to this function at a given time!!! This is normally accomplished
+ * by relying on the module system to only have one copy of the module
+ * loaded, and then by giving the lock_torture_stats kthread full control
+ * (or the init/cleanup functions when lock_torture_stats thread is not
+ * running).
+ */
+static void lock_torture_stats_print(void)
+{
+ int size = nrealwriters_stress * 200 + 8192;
+ char *buf;
+
+ buf = kmalloc(size, GFP_KERNEL);
+ if (!buf) {
+ pr_err("lock_torture_stats_print: Out of memory, need: %d",
+ size);
+ return;
+ }
+ lock_torture_printk(buf);
+ pr_alert("%s", buf);
+ kfree(buf);
+}
+
+/*
+ * Periodically prints torture statistics, if periodic statistics printing
+ * was specified via the stat_interval module parameter.
+ *
+ * No need to worry about fullstop here, since this one doesn't reference
+ * volatile state or register callbacks.
+ */
+static int lock_torture_stats(void *arg)
+{
+ VERBOSE_TOROUT_STRING("lock_torture_stats task started");
+ do {
+ schedule_timeout_interruptible(stat_interval * HZ);
+ lock_torture_stats_print();
+ torture_shutdown_absorb("lock_torture_stats");
+ } while (!torture_must_stop());
+ torture_kthread_stopping("lock_torture_stats");
+ return 0;
+}
+
+static inline void
+lock_torture_print_module_parms(struct lock_torture_ops *cur_ops,
+ const char *tag)
+{
+ pr_alert("%s" TORTURE_FLAG
+ "--- %s: nwriters_stress=%d stat_interval=%d verbose=%d shuffle_interval=%d stutter=%d shutdown_secs=%d onoff_interval=%d onoff_holdoff=%d\n",
+ torture_type, tag, nrealwriters_stress, stat_interval, verbose,
+ shuffle_interval, stutter, shutdown_secs,
+ onoff_interval, onoff_holdoff);
+}
+
+static void lock_torture_cleanup(void)
+{
+ int i;
+
+ if (torture_cleanup())
+ return;
+
+ if (writer_tasks) {
+ for (i = 0; i < nrealwriters_stress; i++)
+ torture_stop_kthread(lock_torture_writer,
+ writer_tasks[i]);
+ kfree(writer_tasks);
+ writer_tasks = NULL;
+ }
+
+ torture_stop_kthread(lock_torture_stats, stats_task);
+ lock_torture_stats_print(); /* -After- the stats thread is stopped! */
+
+ if (atomic_read(&n_lock_torture_errors))
+ lock_torture_print_module_parms(cur_ops,
+ "End of test: FAILURE");
+ else if (torture_onoff_failures())
+ lock_torture_print_module_parms(cur_ops,
+ "End of test: LOCK_HOTPLUG");
+ else
+ lock_torture_print_module_parms(cur_ops,
+ "End of test: SUCCESS");
+}
+
+static int __init lock_torture_init(void)
+{
+ int i;
+ int firsterr = 0;
+ static struct lock_torture_ops *torture_ops[] = {
+ &lock_busted_ops, &spin_lock_ops, &spin_lock_irq_ops,
+ };
+
+ torture_init_begin(torture_type, verbose, &locktorture_runnable);
+
+ /* Process args and tell the world that the torturer is on the job. */
+ for (i = 0; i < ARRAY_SIZE(torture_ops); i++) {
+ cur_ops = torture_ops[i];
+ if (strcmp(torture_type, cur_ops->name) == 0)
+ break;
+ }
+ if (i == ARRAY_SIZE(torture_ops)) {
+ pr_alert("lock-torture: invalid torture type: \"%s\"\n",
+ torture_type);
+ pr_alert("lock-torture types:");
+ for (i = 0; i < ARRAY_SIZE(torture_ops); i++)
+ pr_alert(" %s", torture_ops[i]->name);
+ pr_alert("\n");
+ torture_init_end();
+ return -EINVAL;
+ }
+ if (cur_ops->init)
+ cur_ops->init(); /* no "goto unwind" prior to this point!!! */
+
+ if (nwriters_stress >= 0)
+ nrealwriters_stress = nwriters_stress;
+ else
+ nrealwriters_stress = 2 * num_online_cpus();
+ lock_torture_print_module_parms(cur_ops, "Start of test");
+
+ /* Initialize the statistics so that each run gets its own numbers. */
+
+ lock_is_write_held = 0;
+ lwsa = kmalloc(sizeof(*lwsa) * nrealwriters_stress, GFP_KERNEL);
+ if (lwsa == NULL) {
+ VERBOSE_TOROUT_STRING("lwsa: Out of memory");
+ firsterr = -ENOMEM;
+ goto unwind;
+ }
+ for (i = 0; i < nrealwriters_stress; i++) {
+ lwsa[i].n_write_lock_fail = 0;
+ lwsa[i].n_write_lock_acquired = 0;
+ }
+
+ /* Start up the kthreads. */
+
+ if (onoff_interval > 0) {
+ firsterr = torture_onoff_init(onoff_holdoff * HZ,
+ onoff_interval * HZ);
+ if (firsterr)
+ goto unwind;
+ }
+ if (shuffle_interval > 0) {
+ firsterr = torture_shuffle_init(shuffle_interval);
+ if (firsterr)
+ goto unwind;
+ }
+ if (shutdown_secs > 0) {
+ firsterr = torture_shutdown_init(shutdown_secs,
+ lock_torture_cleanup);
+ if (firsterr)
+ goto unwind;
+ }
+ if (stutter > 0) {
+ firsterr = torture_stutter_init(stutter);
+ if (firsterr)
+ goto unwind;
+ }
+
+ writer_tasks = kzalloc(nrealwriters_stress * sizeof(writer_tasks[0]),
+ GFP_KERNEL);
+ if (writer_tasks == NULL) {
+ VERBOSE_TOROUT_ERRSTRING("writer_tasks: Out of memory");
+ firsterr = -ENOMEM;
+ goto unwind;
+ }
+ for (i = 0; i < nrealwriters_stress; i++) {
+ firsterr = torture_create_kthread(lock_torture_writer, &lwsa[i],
+ writer_tasks[i]);
+ if (firsterr)
+ goto unwind;
+ }
+ if (stat_interval > 0) {
+ firsterr = torture_create_kthread(lock_torture_stats, NULL,
+ stats_task);
+ if (firsterr)
+ goto unwind;
+ }
+ torture_init_end();
+ return 0;
+
+unwind:
+ torture_init_end();
+ lock_torture_cleanup();
+ return firsterr;
+}
+
+module_init(lock_torture_init);
+module_exit(lock_torture_cleanup);
* racy then it does not matter what the result of the test
* is, we re-check the list after having taken the lock anyway:
*/
- if (rcu_dereference_raw(nh->head)) {
+ if (rcu_access_pointer(nh->head)) {
down_read(&nh->rwsem);
ret = notifier_call_chain(&nh->head, val, v, nr_to_call,
nr_calls);
obj-y += update.o srcu.o
-obj-$(CONFIG_RCU_TORTURE_TEST) += torture.o
+obj-$(CONFIG_RCU_TORTURE_TEST) += rcutorture.o
obj-$(CONFIG_TREE_RCU) += tree.o
obj-$(CONFIG_TREE_PREEMPT_RCU) += tree.o
obj-$(CONFIG_TREE_RCU_TRACE) += tree_trace.o
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
*
* Copyright IBM Corporation, 2011
*
#ifndef __LINUX_RCU_H
#define __LINUX_RCU_H
+#include <trace/events/rcu.h>
#ifdef CONFIG_RCU_TRACE
#define RCU_TRACE(stmt) stmt
#else /* #ifdef CONFIG_RCU_TRACE */
}
}
-extern int rcu_expedited;
-
#ifdef CONFIG_RCU_STALL_COMMON
extern int rcu_cpu_stall_suppress;
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
*
* Copyright (C) IBM Corporation, 2005, 2006
*
#include <linux/slab.h>
#include <linux/trace_clock.h>
#include <asm/byteorder.h>
+#include <linux/torture.h>
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com> and Josh Triplett <josh@freedesktop.org>");
-MODULE_ALIAS("rcutorture");
-#ifdef MODULE_PARAM_PREFIX
-#undef MODULE_PARAM_PREFIX
-#endif
-#define MODULE_PARAM_PREFIX "rcutorture."
-
-static int fqs_duration;
-module_param(fqs_duration, int, 0444);
-MODULE_PARM_DESC(fqs_duration, "Duration of fqs bursts (us), 0 to disable");
-static int fqs_holdoff;
-module_param(fqs_holdoff, int, 0444);
-MODULE_PARM_DESC(fqs_holdoff, "Holdoff time within fqs bursts (us)");
-static int fqs_stutter = 3;
-module_param(fqs_stutter, int, 0444);
-MODULE_PARM_DESC(fqs_stutter, "Wait time between fqs bursts (s)");
-static bool gp_exp;
-module_param(gp_exp, bool, 0444);
-MODULE_PARM_DESC(gp_exp, "Use expedited GP wait primitives");
-static bool gp_normal;
-module_param(gp_normal, bool, 0444);
-MODULE_PARM_DESC(gp_normal, "Use normal (non-expedited) GP wait primitives");
-static int irqreader = 1;
-module_param(irqreader, int, 0444);
-MODULE_PARM_DESC(irqreader, "Allow RCU readers from irq handlers");
-static int n_barrier_cbs;
-module_param(n_barrier_cbs, int, 0444);
-MODULE_PARM_DESC(n_barrier_cbs, "# of callbacks/kthreads for barrier testing");
-static int nfakewriters = 4;
-module_param(nfakewriters, int, 0444);
-MODULE_PARM_DESC(nfakewriters, "Number of RCU fake writer threads");
-static int nreaders = -1;
-module_param(nreaders, int, 0444);
-MODULE_PARM_DESC(nreaders, "Number of RCU reader threads");
-static int object_debug;
-module_param(object_debug, int, 0444);
-MODULE_PARM_DESC(object_debug, "Enable debug-object double call_rcu() testing");
-static int onoff_holdoff;
-module_param(onoff_holdoff, int, 0444);
-MODULE_PARM_DESC(onoff_holdoff, "Time after boot before CPU hotplugs (s)");
-static int onoff_interval;
-module_param(onoff_interval, int, 0444);
-MODULE_PARM_DESC(onoff_interval, "Time between CPU hotplugs (s), 0=disable");
-static int shuffle_interval = 3;
-module_param(shuffle_interval, int, 0444);
-MODULE_PARM_DESC(shuffle_interval, "Number of seconds between shuffles");
-static int shutdown_secs;
-module_param(shutdown_secs, int, 0444);
-MODULE_PARM_DESC(shutdown_secs, "Shutdown time (s), <= zero to disable.");
-static int stall_cpu;
-module_param(stall_cpu, int, 0444);
-MODULE_PARM_DESC(stall_cpu, "Stall duration (s), zero to disable.");
-static int stall_cpu_holdoff = 10;
-module_param(stall_cpu_holdoff, int, 0444);
-MODULE_PARM_DESC(stall_cpu_holdoff, "Time to wait before starting stall (s).");
-static int stat_interval = 60;
-module_param(stat_interval, int, 0644);
-MODULE_PARM_DESC(stat_interval, "Number of seconds between stats printk()s");
-static int stutter = 5;
-module_param(stutter, int, 0444);
-MODULE_PARM_DESC(stutter, "Number of seconds to run/halt test");
-static int test_boost = 1;
-module_param(test_boost, int, 0444);
-MODULE_PARM_DESC(test_boost, "Test RCU prio boost: 0=no, 1=maybe, 2=yes.");
-static int test_boost_duration = 4;
-module_param(test_boost_duration, int, 0444);
-MODULE_PARM_DESC(test_boost_duration, "Duration of each boost test, seconds.");
-static int test_boost_interval = 7;
-module_param(test_boost_interval, int, 0444);
-MODULE_PARM_DESC(test_boost_interval, "Interval between boost tests, seconds.");
-static bool test_no_idle_hz = true;
-module_param(test_no_idle_hz, bool, 0444);
-MODULE_PARM_DESC(test_no_idle_hz, "Test support for tickless idle CPUs");
+
+torture_param(int, fqs_duration, 0,
+ "Duration of fqs bursts (us), 0 to disable");
+torture_param(int, fqs_holdoff, 0, "Holdoff time within fqs bursts (us)");
+torture_param(int, fqs_stutter, 3, "Wait time between fqs bursts (s)");
+torture_param(bool, gp_exp, false, "Use expedited GP wait primitives");
+torture_param(bool, gp_normal, false,
+ "Use normal (non-expedited) GP wait primitives");
+torture_param(int, irqreader, 1, "Allow RCU readers from irq handlers");
+torture_param(int, n_barrier_cbs, 0,
+ "# of callbacks/kthreads for barrier testing");
+torture_param(int, nfakewriters, 4, "Number of RCU fake writer threads");
+torture_param(int, nreaders, -1, "Number of RCU reader threads");
+torture_param(int, object_debug, 0,
+ "Enable debug-object double call_rcu() testing");
+torture_param(int, onoff_holdoff, 0, "Time after boot before CPU hotplugs (s)");
+torture_param(int, onoff_interval, 0,
+ "Time between CPU hotplugs (s), 0=disable");
+torture_param(int, shuffle_interval, 3, "Number of seconds between shuffles");
+torture_param(int, shutdown_secs, 0, "Shutdown time (s), <= zero to disable.");
+torture_param(int, stall_cpu, 0, "Stall duration (s), zero to disable.");
+torture_param(int, stall_cpu_holdoff, 10,
+ "Time to wait before starting stall (s).");
+torture_param(int, stat_interval, 60,
+ "Number of seconds between stats printk()s");
+torture_param(int, stutter, 5, "Number of seconds to run/halt test");
+torture_param(int, test_boost, 1, "Test RCU prio boost: 0=no, 1=maybe, 2=yes.");
+torture_param(int, test_boost_duration, 4,
+ "Duration of each boost test, seconds.");
+torture_param(int, test_boost_interval, 7,
+ "Interval between boost tests, seconds.");
+torture_param(bool, test_no_idle_hz, true,
+ "Test support for tickless idle CPUs");
+torture_param(bool, verbose, true,
+ "Enable verbose debugging printk()s");
+
static char *torture_type = "rcu";
module_param(torture_type, charp, 0444);
MODULE_PARM_DESC(torture_type, "Type of RCU to torture (rcu, rcu_bh, ...)");
-static bool verbose;
-module_param(verbose, bool, 0444);
-MODULE_PARM_DESC(verbose, "Enable verbose debugging printk()s");
-
-#define TORTURE_FLAG "-torture:"
-#define PRINTK_STRING(s) \
- do { pr_alert("%s" TORTURE_FLAG s "\n", torture_type); } while (0)
-#define VERBOSE_PRINTK_STRING(s) \
- do { if (verbose) pr_alert("%s" TORTURE_FLAG s "\n", torture_type); } while (0)
-#define VERBOSE_PRINTK_ERRSTRING(s) \
- do { if (verbose) pr_alert("%s" TORTURE_FLAG "!!! " s "\n", torture_type); } while (0)
static int nrealreaders;
static struct task_struct *writer_task;
static struct task_struct **fakewriter_tasks;
static struct task_struct **reader_tasks;
static struct task_struct *stats_task;
-static struct task_struct *shuffler_task;
-static struct task_struct *stutter_task;
static struct task_struct *fqs_task;
static struct task_struct *boost_tasks[NR_CPUS];
-static struct task_struct *shutdown_task;
-#ifdef CONFIG_HOTPLUG_CPU
-static struct task_struct *onoff_task;
-#endif /* #ifdef CONFIG_HOTPLUG_CPU */
static struct task_struct *stall_task;
static struct task_struct **barrier_cbs_tasks;
static struct task_struct *barrier_task;
static unsigned long rcu_torture_current_version;
static struct rcu_torture rcu_tortures[10 * RCU_TORTURE_PIPE_LEN];
static DEFINE_SPINLOCK(rcu_torture_lock);
-static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_count) =
- { 0 };
-static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_batch) =
- { 0 };
+static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1],
+ rcu_torture_count) = { 0 };
+static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1],
+ rcu_torture_batch) = { 0 };
static atomic_t rcu_torture_wcount[RCU_TORTURE_PIPE_LEN + 1];
static atomic_t n_rcu_torture_alloc;
static atomic_t n_rcu_torture_alloc_fail;
static long n_rcu_torture_boost_failure;
static long n_rcu_torture_boosts;
static long n_rcu_torture_timers;
-static long n_offline_attempts;
-static long n_offline_successes;
-static unsigned long sum_offline;
-static int min_offline = -1;
-static int max_offline;
-static long n_online_attempts;
-static long n_online_successes;
-static unsigned long sum_online;
-static int min_online = -1;
-static int max_online;
static long n_barrier_attempts;
static long n_barrier_successes;
static struct list_head rcu_torture_removed;
-static cpumask_var_t shuffle_tmp_mask;
-
-static int stutter_pause_test;
#if defined(MODULE) || defined(CONFIG_RCU_TORTURE_TEST_RUNNABLE)
#define RCUTORTURE_RUNNABLE_INIT 1
}
#endif /* #else #ifdef CONFIG_RCU_TRACE */
-static unsigned long shutdown_time; /* jiffies to system shutdown. */
static unsigned long boost_starttime; /* jiffies of next boost test start. */
DEFINE_MUTEX(boost_mutex); /* protect setting boost_starttime */
/* and boost task create/destroy. */
static wait_queue_head_t *barrier_cbs_wq; /* Coordinate barrier testing. */
static DECLARE_WAIT_QUEUE_HEAD(barrier_wq);
-/* Mediate rmmod and system shutdown. Concurrent rmmod & shutdown illegal! */
-
-#define FULLSTOP_DONTSTOP 0 /* Normal operation. */
-#define FULLSTOP_SHUTDOWN 1 /* System shutdown with rcutorture running. */
-#define FULLSTOP_RMMOD 2 /* Normal rmmod of rcutorture. */
-static int fullstop = FULLSTOP_RMMOD;
-/*
- * Protect fullstop transitions and spawning of kthreads.
- */
-static DEFINE_MUTEX(fullstop_mutex);
-
-/* Forward reference. */
-static void rcu_torture_cleanup(void);
-
-/*
- * Detect and respond to a system shutdown.
- */
-static int
-rcutorture_shutdown_notify(struct notifier_block *unused1,
- unsigned long unused2, void *unused3)
-{
- mutex_lock(&fullstop_mutex);
- if (fullstop == FULLSTOP_DONTSTOP)
- fullstop = FULLSTOP_SHUTDOWN;
- else
- pr_warn(/* but going down anyway, so... */
- "Concurrent 'rmmod rcutorture' and shutdown illegal!\n");
- mutex_unlock(&fullstop_mutex);
- return NOTIFY_DONE;
-}
-
-/*
- * Absorb kthreads into a kernel function that won't return, so that
- * they won't ever access module text or data again.
- */
-static void rcutorture_shutdown_absorb(const char *title)
-{
- if (ACCESS_ONCE(fullstop) == FULLSTOP_SHUTDOWN) {
- pr_notice(
- "rcutorture thread %s parking due to system shutdown\n",
- title);
- schedule_timeout_uninterruptible(MAX_SCHEDULE_TIMEOUT);
- }
-}
-
/*
* Allocate an element from the rcu_tortures pool.
*/
spin_unlock_bh(&rcu_torture_lock);
}
-struct rcu_random_state {
- unsigned long rrs_state;
- long rrs_count;
-};
-
-#define RCU_RANDOM_MULT 39916801 /* prime */
-#define RCU_RANDOM_ADD 479001701 /* prime */
-#define RCU_RANDOM_REFRESH 10000
-
-#define DEFINE_RCU_RANDOM(name) struct rcu_random_state name = { 0, 0 }
-
-/*
- * Crude but fast random-number generator. Uses a linear congruential
- * generator, with occasional help from cpu_clock().
- */
-static unsigned long
-rcu_random(struct rcu_random_state *rrsp)
-{
- if (--rrsp->rrs_count < 0) {
- rrsp->rrs_state += (unsigned long)local_clock();
- rrsp->rrs_count = RCU_RANDOM_REFRESH;
- }
- rrsp->rrs_state = rrsp->rrs_state * RCU_RANDOM_MULT + RCU_RANDOM_ADD;
- return swahw32(rrsp->rrs_state);
-}
-
-static void
-rcu_stutter_wait(const char *title)
-{
- while (stutter_pause_test || !rcutorture_runnable) {
- if (rcutorture_runnable)
- schedule_timeout_interruptible(1);
- else
- schedule_timeout_interruptible(round_jiffies_relative(HZ));
- rcutorture_shutdown_absorb(title);
- }
-}
-
/*
* Operations vector for selecting different types of tests.
*/
struct rcu_torture_ops {
void (*init)(void);
int (*readlock)(void);
- void (*read_delay)(struct rcu_random_state *rrsp);
+ void (*read_delay)(struct torture_random_state *rrsp);
void (*readunlock)(int idx);
int (*completed)(void);
void (*deferred_free)(struct rcu_torture *p);
return 0;
}
-static void rcu_read_delay(struct rcu_random_state *rrsp)
+static void rcu_read_delay(struct torture_random_state *rrsp)
{
const unsigned long shortdelay_us = 200;
const unsigned long longdelay_ms = 50;
* period, and we want a long delay occasionally to trigger
* force_quiescent_state. */
- if (!(rcu_random(rrsp) % (nrealreaders * 2000 * longdelay_ms)))
+ if (!(torture_random(rrsp) % (nrealreaders * 2000 * longdelay_ms)))
mdelay(longdelay_ms);
- if (!(rcu_random(rrsp) % (nrealreaders * 2 * shortdelay_us)))
+ if (!(torture_random(rrsp) % (nrealreaders * 2 * shortdelay_us)))
udelay(shortdelay_us);
#ifdef CONFIG_PREEMPT
- if (!preempt_count() && !(rcu_random(rrsp) % (nrealreaders * 20000)))
+ if (!preempt_count() &&
+ !(torture_random(rrsp) % (nrealreaders * 20000)))
preempt_schedule(); /* No QS if preempt_disable() in effect */
#endif
}
int i;
struct rcu_torture *rp = container_of(p, struct rcu_torture, rtort_rcu);
- if (fullstop != FULLSTOP_DONTSTOP) {
+ if (torture_must_stop_irq()) {
/* Test is ending, just drop callbacks on the floor. */
/* The next initialization will pick up the pieces. */
return;
.name = "rcu_bh"
};
+/*
+ * Don't even think about trying any of these in real life!!!
+ * The names includes "busted", and they really means it!
+ * The only purpose of these functions is to provide a buggy RCU
+ * implementation to make sure that rcutorture correctly emits
+ * buggy-RCU error messages.
+ */
+static void rcu_busted_torture_deferred_free(struct rcu_torture *p)
+{
+ /* This is a deliberate bug for testing purposes only! */
+ rcu_torture_cb(&p->rtort_rcu);
+}
+
+static void synchronize_rcu_busted(void)
+{
+ /* This is a deliberate bug for testing purposes only! */
+}
+
+static void
+call_rcu_busted(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
+{
+ /* This is a deliberate bug for testing purposes only! */
+ func(head);
+}
+
+static struct rcu_torture_ops rcu_busted_ops = {
+ .init = rcu_sync_torture_init,
+ .readlock = rcu_torture_read_lock,
+ .read_delay = rcu_read_delay, /* just reuse rcu's version. */
+ .readunlock = rcu_torture_read_unlock,
+ .completed = rcu_no_completed,
+ .deferred_free = rcu_busted_torture_deferred_free,
+ .sync = synchronize_rcu_busted,
+ .exp_sync = synchronize_rcu_busted,
+ .call = call_rcu_busted,
+ .cb_barrier = NULL,
+ .fqs = NULL,
+ .stats = NULL,
+ .irq_capable = 1,
+ .name = "rcu_busted"
+};
+
/*
* Definitions for srcu torture testing.
*/
return srcu_read_lock(&srcu_ctl);
}
-static void srcu_read_delay(struct rcu_random_state *rrsp)
+static void srcu_read_delay(struct torture_random_state *rrsp)
{
long delay;
const long uspertick = 1000000 / HZ;
/* We want there to be long-running readers, but not all the time. */
- delay = rcu_random(rrsp) % (nrealreaders * 2 * longdelay * uspertick);
+ delay = torture_random(rrsp) %
+ (nrealreaders * 2 * longdelay * uspertick);
if (!delay)
schedule_timeout_interruptible(longdelay);
else
struct rcu_boost_inflight rbi = { .inflight = 0 };
struct sched_param sp;
- VERBOSE_PRINTK_STRING("rcu_torture_boost started");
+ VERBOSE_TOROUT_STRING("rcu_torture_boost started");
/* Set real-time priority. */
sp.sched_priority = 1;
if (sched_setscheduler(current, SCHED_FIFO, &sp) < 0) {
- VERBOSE_PRINTK_STRING("rcu_torture_boost RT prio failed!");
+ VERBOSE_TOROUT_STRING("rcu_torture_boost RT prio failed!");
n_rcu_torture_boost_rterror++;
}
oldstarttime = boost_starttime;
while (ULONG_CMP_LT(jiffies, oldstarttime)) {
schedule_timeout_interruptible(oldstarttime - jiffies);
- rcu_stutter_wait("rcu_torture_boost");
- if (kthread_should_stop() ||
- fullstop != FULLSTOP_DONTSTOP)
+ stutter_wait("rcu_torture_boost");
+ if (torture_must_stop())
goto checkwait;
}
call_rcu(&rbi.rcu, rcu_torture_boost_cb);
if (jiffies - call_rcu_time >
test_boost_duration * HZ - HZ / 2) {
- VERBOSE_PRINTK_STRING("rcu_torture_boost boosting failed");
+ VERBOSE_TOROUT_STRING("rcu_torture_boost boosting failed");
n_rcu_torture_boost_failure++;
}
call_rcu_time = jiffies;
}
cond_resched();
- rcu_stutter_wait("rcu_torture_boost");
- if (kthread_should_stop() ||
- fullstop != FULLSTOP_DONTSTOP)
+ stutter_wait("rcu_torture_boost");
+ if (torture_must_stop())
goto checkwait;
}
}
/* Go do the stutter. */
-checkwait: rcu_stutter_wait("rcu_torture_boost");
- } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
+checkwait: stutter_wait("rcu_torture_boost");
+ } while (!torture_must_stop());
/* Clean up and exit. */
- VERBOSE_PRINTK_STRING("rcu_torture_boost task stopping");
- rcutorture_shutdown_absorb("rcu_torture_boost");
- while (!kthread_should_stop() || rbi.inflight)
+ while (!kthread_should_stop() || rbi.inflight) {
+ torture_shutdown_absorb("rcu_torture_boost");
schedule_timeout_uninterruptible(1);
+ }
smp_mb(); /* order accesses to ->inflight before stack-frame death. */
destroy_rcu_head_on_stack(&rbi.rcu);
+ torture_kthread_stopping("rcu_torture_boost");
return 0;
}
unsigned long fqs_resume_time;
int fqs_burst_remaining;
- VERBOSE_PRINTK_STRING("rcu_torture_fqs task started");
+ VERBOSE_TOROUT_STRING("rcu_torture_fqs task started");
do {
fqs_resume_time = jiffies + fqs_stutter * HZ;
while (ULONG_CMP_LT(jiffies, fqs_resume_time) &&
udelay(fqs_holdoff);
fqs_burst_remaining -= fqs_holdoff;
}
- rcu_stutter_wait("rcu_torture_fqs");
- } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
- VERBOSE_PRINTK_STRING("rcu_torture_fqs task stopping");
- rcutorture_shutdown_absorb("rcu_torture_fqs");
- while (!kthread_should_stop())
- schedule_timeout_uninterruptible(1);
+ stutter_wait("rcu_torture_fqs");
+ } while (!torture_must_stop());
+ torture_kthread_stopping("rcu_torture_fqs");
return 0;
}
struct rcu_torture *rp;
struct rcu_torture *rp1;
struct rcu_torture *old_rp;
- static DEFINE_RCU_RANDOM(rand);
+ static DEFINE_TORTURE_RANDOM(rand);
- VERBOSE_PRINTK_STRING("rcu_torture_writer task started");
+ VERBOSE_TOROUT_STRING("rcu_torture_writer task started");
set_user_nice(current, 19);
do {
if (rp == NULL)
continue;
rp->rtort_pipe_count = 0;
- udelay(rcu_random(&rand) & 0x3ff);
+ udelay(torture_random(&rand) & 0x3ff);
old_rp = rcu_dereference_check(rcu_torture_current,
current == writer_task);
rp->rtort_mbtest = 1;
atomic_inc(&rcu_torture_wcount[i]);
old_rp->rtort_pipe_count++;
if (gp_normal == gp_exp)
- exp = !!(rcu_random(&rand) & 0x80);
+ exp = !!(torture_random(&rand) & 0x80);
else
exp = gp_exp;
if (!exp) {
}
}
rcutorture_record_progress(++rcu_torture_current_version);
- rcu_stutter_wait("rcu_torture_writer");
- } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
- VERBOSE_PRINTK_STRING("rcu_torture_writer task stopping");
- rcutorture_shutdown_absorb("rcu_torture_writer");
- while (!kthread_should_stop())
- schedule_timeout_uninterruptible(1);
+ stutter_wait("rcu_torture_writer");
+ } while (!torture_must_stop());
+ torture_kthread_stopping("rcu_torture_writer");
return 0;
}
static int
rcu_torture_fakewriter(void *arg)
{
- DEFINE_RCU_RANDOM(rand);
+ DEFINE_TORTURE_RANDOM(rand);
- VERBOSE_PRINTK_STRING("rcu_torture_fakewriter task started");
+ VERBOSE_TOROUT_STRING("rcu_torture_fakewriter task started");
set_user_nice(current, 19);
do {
- schedule_timeout_uninterruptible(1 + rcu_random(&rand)%10);
- udelay(rcu_random(&rand) & 0x3ff);
+ schedule_timeout_uninterruptible(1 + torture_random(&rand)%10);
+ udelay(torture_random(&rand) & 0x3ff);
if (cur_ops->cb_barrier != NULL &&
- rcu_random(&rand) % (nfakewriters * 8) == 0) {
+ torture_random(&rand) % (nfakewriters * 8) == 0) {
cur_ops->cb_barrier();
} else if (gp_normal == gp_exp) {
- if (rcu_random(&rand) & 0x80)
+ if (torture_random(&rand) & 0x80)
cur_ops->sync();
else
cur_ops->exp_sync();
} else {
cur_ops->exp_sync();
}
- rcu_stutter_wait("rcu_torture_fakewriter");
- } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
+ stutter_wait("rcu_torture_fakewriter");
+ } while (!torture_must_stop());
- VERBOSE_PRINTK_STRING("rcu_torture_fakewriter task stopping");
- rcutorture_shutdown_absorb("rcu_torture_fakewriter");
- while (!kthread_should_stop())
- schedule_timeout_uninterruptible(1);
+ torture_kthread_stopping("rcu_torture_fakewriter");
return 0;
}
int idx;
int completed;
int completed_end;
- static DEFINE_RCU_RANDOM(rand);
+ static DEFINE_TORTURE_RANDOM(rand);
static DEFINE_SPINLOCK(rand_lock);
struct rcu_torture *p;
int pipe_count;
int completed;
int completed_end;
int idx;
- DEFINE_RCU_RANDOM(rand);
+ DEFINE_TORTURE_RANDOM(rand);
struct rcu_torture *p;
int pipe_count;
struct timer_list t;
unsigned long long ts;
- VERBOSE_PRINTK_STRING("rcu_torture_reader task started");
+ VERBOSE_TOROUT_STRING("rcu_torture_reader task started");
set_user_nice(current, 19);
if (irqreader && cur_ops->irq_capable)
setup_timer_on_stack(&t, rcu_torture_timer, 0);
preempt_enable();
cur_ops->readunlock(idx);
schedule();
- rcu_stutter_wait("rcu_torture_reader");
- } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
- VERBOSE_PRINTK_STRING("rcu_torture_reader task stopping");
- rcutorture_shutdown_absorb("rcu_torture_reader");
+ stutter_wait("rcu_torture_reader");
+ } while (!torture_must_stop());
if (irqreader && cur_ops->irq_capable)
del_timer_sync(&t);
- while (!kthread_should_stop())
- schedule_timeout_uninterruptible(1);
+ torture_kthread_stopping("rcu_torture_reader");
return 0;
}
n_rcu_torture_boost_failure,
n_rcu_torture_boosts,
n_rcu_torture_timers);
- page += sprintf(page,
- "onoff: %ld/%ld:%ld/%ld %d,%d:%d,%d %lu:%lu (HZ=%d) ",
- n_online_successes, n_online_attempts,
- n_offline_successes, n_offline_attempts,
- min_online, max_online,
- min_offline, max_offline,
- sum_online, sum_offline, HZ);
+ page = torture_onoff_stats(page);
page += sprintf(page, "barrier: %ld/%ld:%ld",
n_barrier_successes,
n_barrier_attempts,
/*
* Periodically prints torture statistics, if periodic statistics printing
* was specified via the stat_interval module parameter.
- *
- * No need to worry about fullstop here, since this one doesn't reference
- * volatile state or register callbacks.
*/
static int
rcu_torture_stats(void *arg)
{
- VERBOSE_PRINTK_STRING("rcu_torture_stats task started");
+ VERBOSE_TOROUT_STRING("rcu_torture_stats task started");
do {
schedule_timeout_interruptible(stat_interval * HZ);
rcu_torture_stats_print();
- rcutorture_shutdown_absorb("rcu_torture_stats");
- } while (!kthread_should_stop());
- VERBOSE_PRINTK_STRING("rcu_torture_stats task stopping");
- return 0;
-}
-
-static int rcu_idle_cpu; /* Force all torture tasks off this CPU */
-
-/* Shuffle tasks such that we allow @rcu_idle_cpu to become idle. A special case
- * is when @rcu_idle_cpu = -1, when we allow the tasks to run on all CPUs.
- */
-static void rcu_torture_shuffle_tasks(void)
-{
- int i;
-
- cpumask_setall(shuffle_tmp_mask);
- get_online_cpus();
-
- /* No point in shuffling if there is only one online CPU (ex: UP) */
- if (num_online_cpus() == 1) {
- put_online_cpus();
- return;
- }
-
- if (rcu_idle_cpu != -1)
- cpumask_clear_cpu(rcu_idle_cpu, shuffle_tmp_mask);
-
- set_cpus_allowed_ptr(current, shuffle_tmp_mask);
-
- if (reader_tasks) {
- for (i = 0; i < nrealreaders; i++)
- if (reader_tasks[i])
- set_cpus_allowed_ptr(reader_tasks[i],
- shuffle_tmp_mask);
- }
- if (fakewriter_tasks) {
- for (i = 0; i < nfakewriters; i++)
- if (fakewriter_tasks[i])
- set_cpus_allowed_ptr(fakewriter_tasks[i],
- shuffle_tmp_mask);
- }
- if (writer_task)
- set_cpus_allowed_ptr(writer_task, shuffle_tmp_mask);
- if (stats_task)
- set_cpus_allowed_ptr(stats_task, shuffle_tmp_mask);
- if (stutter_task)
- set_cpus_allowed_ptr(stutter_task, shuffle_tmp_mask);
- if (fqs_task)
- set_cpus_allowed_ptr(fqs_task, shuffle_tmp_mask);
- if (shutdown_task)
- set_cpus_allowed_ptr(shutdown_task, shuffle_tmp_mask);
-#ifdef CONFIG_HOTPLUG_CPU
- if (onoff_task)
- set_cpus_allowed_ptr(onoff_task, shuffle_tmp_mask);
-#endif /* #ifdef CONFIG_HOTPLUG_CPU */
- if (stall_task)
- set_cpus_allowed_ptr(stall_task, shuffle_tmp_mask);
- if (barrier_cbs_tasks)
- for (i = 0; i < n_barrier_cbs; i++)
- if (barrier_cbs_tasks[i])
- set_cpus_allowed_ptr(barrier_cbs_tasks[i],
- shuffle_tmp_mask);
- if (barrier_task)
- set_cpus_allowed_ptr(barrier_task, shuffle_tmp_mask);
-
- if (rcu_idle_cpu == -1)
- rcu_idle_cpu = num_online_cpus() - 1;
- else
- rcu_idle_cpu--;
-
- put_online_cpus();
-}
-
-/* Shuffle tasks across CPUs, with the intent of allowing each CPU in the
- * system to become idle at a time and cut off its timer ticks. This is meant
- * to test the support for such tickless idle CPU in RCU.
- */
-static int
-rcu_torture_shuffle(void *arg)
-{
- VERBOSE_PRINTK_STRING("rcu_torture_shuffle task started");
- do {
- schedule_timeout_interruptible(shuffle_interval * HZ);
- rcu_torture_shuffle_tasks();
- rcutorture_shutdown_absorb("rcu_torture_shuffle");
- } while (!kthread_should_stop());
- VERBOSE_PRINTK_STRING("rcu_torture_shuffle task stopping");
- return 0;
-}
-
-/* Cause the rcutorture test to "stutter", starting and stopping all
- * threads periodically.
- */
-static int
-rcu_torture_stutter(void *arg)
-{
- VERBOSE_PRINTK_STRING("rcu_torture_stutter task started");
- do {
- schedule_timeout_interruptible(stutter * HZ);
- stutter_pause_test = 1;
- if (!kthread_should_stop())
- schedule_timeout_interruptible(stutter * HZ);
- stutter_pause_test = 0;
- rcutorture_shutdown_absorb("rcu_torture_stutter");
- } while (!kthread_should_stop());
- VERBOSE_PRINTK_STRING("rcu_torture_stutter task stopping");
+ torture_shutdown_absorb("rcu_torture_stats");
+ } while (!torture_must_stop());
+ torture_kthread_stopping("rcu_torture_stats");
return 0;
}
onoff_interval, onoff_holdoff);
}
-static struct notifier_block rcutorture_shutdown_nb = {
- .notifier_call = rcutorture_shutdown_notify,
-};
-
static void rcutorture_booster_cleanup(int cpu)
{
struct task_struct *t;
if (boost_tasks[cpu] == NULL)
return;
mutex_lock(&boost_mutex);
- VERBOSE_PRINTK_STRING("Stopping rcu_torture_boost task");
t = boost_tasks[cpu];
boost_tasks[cpu] = NULL;
mutex_unlock(&boost_mutex);
/* This must be outside of the mutex, otherwise deadlock! */
- kthread_stop(t);
- boost_tasks[cpu] = NULL;
+ torture_stop_kthread(rcu_torture_boost, t);
}
static int rcutorture_booster_init(int cpu)
/* Don't allow time recalculation while creating a new task. */
mutex_lock(&boost_mutex);
- VERBOSE_PRINTK_STRING("Creating rcu_torture_boost task");
+ VERBOSE_TOROUT_STRING("Creating rcu_torture_boost task");
boost_tasks[cpu] = kthread_create_on_node(rcu_torture_boost, NULL,
cpu_to_node(cpu),
"rcu_torture_boost");
if (IS_ERR(boost_tasks[cpu])) {
retval = PTR_ERR(boost_tasks[cpu]);
- VERBOSE_PRINTK_STRING("rcu_torture_boost task create failed");
+ VERBOSE_TOROUT_STRING("rcu_torture_boost task create failed");
n_rcu_torture_boost_ktrerror++;
boost_tasks[cpu] = NULL;
mutex_unlock(&boost_mutex);
return 0;
}
-/*
- * Cause the rcutorture test to shutdown the system after the test has
- * run for the time specified by the shutdown_secs module parameter.
- */
-static int
-rcu_torture_shutdown(void *arg)
-{
- long delta;
- unsigned long jiffies_snap;
-
- VERBOSE_PRINTK_STRING("rcu_torture_shutdown task started");
- jiffies_snap = ACCESS_ONCE(jiffies);
- while (ULONG_CMP_LT(jiffies_snap, shutdown_time) &&
- !kthread_should_stop()) {
- delta = shutdown_time - jiffies_snap;
- if (verbose)
- pr_alert("%s" TORTURE_FLAG
- "rcu_torture_shutdown task: %lu jiffies remaining\n",
- torture_type, delta);
- schedule_timeout_interruptible(delta);
- jiffies_snap = ACCESS_ONCE(jiffies);
- }
- if (kthread_should_stop()) {
- VERBOSE_PRINTK_STRING("rcu_torture_shutdown task stopping");
- return 0;
- }
-
- /* OK, shut down the system. */
-
- VERBOSE_PRINTK_STRING("rcu_torture_shutdown task shutting down system");
- shutdown_task = NULL; /* Avoid self-kill deadlock. */
- rcu_torture_cleanup(); /* Get the success/failure message. */
- kernel_power_off(); /* Shut down the system. */
- return 0;
-}
-
-#ifdef CONFIG_HOTPLUG_CPU
-
-/*
- * Execute random CPU-hotplug operations at the interval specified
- * by the onoff_interval.
- */
-static int
-rcu_torture_onoff(void *arg)
-{
- int cpu;
- unsigned long delta;
- int maxcpu = -1;
- DEFINE_RCU_RANDOM(rand);
- int ret;
- unsigned long starttime;
-
- VERBOSE_PRINTK_STRING("rcu_torture_onoff task started");
- for_each_online_cpu(cpu)
- maxcpu = cpu;
- WARN_ON(maxcpu < 0);
- if (onoff_holdoff > 0) {
- VERBOSE_PRINTK_STRING("rcu_torture_onoff begin holdoff");
- schedule_timeout_interruptible(onoff_holdoff * HZ);
- VERBOSE_PRINTK_STRING("rcu_torture_onoff end holdoff");
- }
- while (!kthread_should_stop()) {
- cpu = (rcu_random(&rand) >> 4) % (maxcpu + 1);
- if (cpu_online(cpu) && cpu_is_hotpluggable(cpu)) {
- if (verbose)
- pr_alert("%s" TORTURE_FLAG
- "rcu_torture_onoff task: offlining %d\n",
- torture_type, cpu);
- starttime = jiffies;
- n_offline_attempts++;
- ret = cpu_down(cpu);
- if (ret) {
- if (verbose)
- pr_alert("%s" TORTURE_FLAG
- "rcu_torture_onoff task: offline %d failed: errno %d\n",
- torture_type, cpu, ret);
- } else {
- if (verbose)
- pr_alert("%s" TORTURE_FLAG
- "rcu_torture_onoff task: offlined %d\n",
- torture_type, cpu);
- n_offline_successes++;
- delta = jiffies - starttime;
- sum_offline += delta;
- if (min_offline < 0) {
- min_offline = delta;
- max_offline = delta;
- }
- if (min_offline > delta)
- min_offline = delta;
- if (max_offline < delta)
- max_offline = delta;
- }
- } else if (cpu_is_hotpluggable(cpu)) {
- if (verbose)
- pr_alert("%s" TORTURE_FLAG
- "rcu_torture_onoff task: onlining %d\n",
- torture_type, cpu);
- starttime = jiffies;
- n_online_attempts++;
- ret = cpu_up(cpu);
- if (ret) {
- if (verbose)
- pr_alert("%s" TORTURE_FLAG
- "rcu_torture_onoff task: online %d failed: errno %d\n",
- torture_type, cpu, ret);
- } else {
- if (verbose)
- pr_alert("%s" TORTURE_FLAG
- "rcu_torture_onoff task: onlined %d\n",
- torture_type, cpu);
- n_online_successes++;
- delta = jiffies - starttime;
- sum_online += delta;
- if (min_online < 0) {
- min_online = delta;
- max_online = delta;
- }
- if (min_online > delta)
- min_online = delta;
- if (max_online < delta)
- max_online = delta;
- }
- }
- schedule_timeout_interruptible(onoff_interval * HZ);
- }
- VERBOSE_PRINTK_STRING("rcu_torture_onoff task stopping");
- return 0;
-}
-
-static int
-rcu_torture_onoff_init(void)
-{
- int ret;
-
- if (onoff_interval <= 0)
- return 0;
- onoff_task = kthread_run(rcu_torture_onoff, NULL, "rcu_torture_onoff");
- if (IS_ERR(onoff_task)) {
- ret = PTR_ERR(onoff_task);
- onoff_task = NULL;
- return ret;
- }
- return 0;
-}
-
-static void rcu_torture_onoff_cleanup(void)
-{
- if (onoff_task == NULL)
- return;
- VERBOSE_PRINTK_STRING("Stopping rcu_torture_onoff task");
- kthread_stop(onoff_task);
- onoff_task = NULL;
-}
-
-#else /* #ifdef CONFIG_HOTPLUG_CPU */
-
-static int
-rcu_torture_onoff_init(void)
-{
- return 0;
-}
-
-static void rcu_torture_onoff_cleanup(void)
-{
-}
-
-#endif /* #else #ifdef CONFIG_HOTPLUG_CPU */
-
/*
* CPU-stall kthread. It waits as specified by stall_cpu_holdoff, then
* induces a CPU stall for the time specified by stall_cpu.
{
unsigned long stop_at;
- VERBOSE_PRINTK_STRING("rcu_torture_stall task started");
+ VERBOSE_TOROUT_STRING("rcu_torture_stall task started");
if (stall_cpu_holdoff > 0) {
- VERBOSE_PRINTK_STRING("rcu_torture_stall begin holdoff");
+ VERBOSE_TOROUT_STRING("rcu_torture_stall begin holdoff");
schedule_timeout_interruptible(stall_cpu_holdoff * HZ);
- VERBOSE_PRINTK_STRING("rcu_torture_stall end holdoff");
+ VERBOSE_TOROUT_STRING("rcu_torture_stall end holdoff");
}
if (!kthread_should_stop()) {
stop_at = get_seconds() + stall_cpu;
rcu_read_unlock();
pr_alert("rcu_torture_stall end.\n");
}
- rcutorture_shutdown_absorb("rcu_torture_stall");
+ torture_shutdown_absorb("rcu_torture_stall");
while (!kthread_should_stop())
schedule_timeout_interruptible(10 * HZ);
return 0;
/* Spawn CPU-stall kthread, if stall_cpu specified. */
static int __init rcu_torture_stall_init(void)
{
- int ret;
-
if (stall_cpu <= 0)
return 0;
- stall_task = kthread_run(rcu_torture_stall, NULL, "rcu_torture_stall");
- if (IS_ERR(stall_task)) {
- ret = PTR_ERR(stall_task);
- stall_task = NULL;
- return ret;
- }
- return 0;
-}
-
-/* Clean up after the CPU-stall kthread, if one was spawned. */
-static void rcu_torture_stall_cleanup(void)
-{
- if (stall_task == NULL)
- return;
- VERBOSE_PRINTK_STRING("Stopping rcu_torture_stall_task.");
- kthread_stop(stall_task);
- stall_task = NULL;
+ return torture_create_kthread(rcu_torture_stall, NULL, stall_task);
}
/* Callback function for RCU barrier testing. */
struct rcu_head rcu;
init_rcu_head_on_stack(&rcu);
- VERBOSE_PRINTK_STRING("rcu_torture_barrier_cbs task started");
+ VERBOSE_TOROUT_STRING("rcu_torture_barrier_cbs task started");
set_user_nice(current, 19);
do {
wait_event(barrier_cbs_wq[myid],
(newphase =
ACCESS_ONCE(barrier_phase)) != lastphase ||
- kthread_should_stop() ||
- fullstop != FULLSTOP_DONTSTOP);
+ torture_must_stop());
lastphase = newphase;
smp_mb(); /* ensure barrier_phase load before ->call(). */
- if (kthread_should_stop() || fullstop != FULLSTOP_DONTSTOP)
+ if (torture_must_stop())
break;
cur_ops->call(&rcu, rcu_torture_barrier_cbf);
if (atomic_dec_and_test(&barrier_cbs_count))
wake_up(&barrier_wq);
- } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
- VERBOSE_PRINTK_STRING("rcu_torture_barrier_cbs task stopping");
- rcutorture_shutdown_absorb("rcu_torture_barrier_cbs");
- while (!kthread_should_stop())
- schedule_timeout_interruptible(1);
+ } while (!torture_must_stop());
cur_ops->cb_barrier();
destroy_rcu_head_on_stack(&rcu);
+ torture_kthread_stopping("rcu_torture_barrier_cbs");
return 0;
}
{
int i;
- VERBOSE_PRINTK_STRING("rcu_torture_barrier task starting");
+ VERBOSE_TOROUT_STRING("rcu_torture_barrier task starting");
do {
atomic_set(&barrier_cbs_invoked, 0);
atomic_set(&barrier_cbs_count, n_barrier_cbs);
wake_up(&barrier_cbs_wq[i]);
wait_event(barrier_wq,
atomic_read(&barrier_cbs_count) == 0 ||
- kthread_should_stop() ||
- fullstop != FULLSTOP_DONTSTOP);
- if (kthread_should_stop() || fullstop != FULLSTOP_DONTSTOP)
+ torture_must_stop());
+ if (torture_must_stop())
break;
n_barrier_attempts++;
cur_ops->cb_barrier(); /* Implies smp_mb() for wait_event(). */
}
n_barrier_successes++;
schedule_timeout_interruptible(HZ / 10);
- } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP);
- VERBOSE_PRINTK_STRING("rcu_torture_barrier task stopping");
- rcutorture_shutdown_absorb("rcu_torture_barrier");
- while (!kthread_should_stop())
- schedule_timeout_interruptible(1);
+ } while (!torture_must_stop());
+ torture_kthread_stopping("rcu_torture_barrier");
return 0;
}
return -ENOMEM;
for (i = 0; i < n_barrier_cbs; i++) {
init_waitqueue_head(&barrier_cbs_wq[i]);
- barrier_cbs_tasks[i] = kthread_run(rcu_torture_barrier_cbs,
- (void *)(long)i,
- "rcu_torture_barrier_cbs");
- if (IS_ERR(barrier_cbs_tasks[i])) {
- ret = PTR_ERR(barrier_cbs_tasks[i]);
- VERBOSE_PRINTK_ERRSTRING("Failed to create rcu_torture_barrier_cbs");
- barrier_cbs_tasks[i] = NULL;
+ ret = torture_create_kthread(rcu_torture_barrier_cbs,
+ (void *)(long)i,
+ barrier_cbs_tasks[i]);
+ if (ret)
return ret;
- }
}
- barrier_task = kthread_run(rcu_torture_barrier, NULL,
- "rcu_torture_barrier");
- if (IS_ERR(barrier_task)) {
- ret = PTR_ERR(barrier_task);
- VERBOSE_PRINTK_ERRSTRING("Failed to create rcu_torture_barrier");
- barrier_task = NULL;
- }
- return 0;
+ return torture_create_kthread(rcu_torture_barrier, NULL, barrier_task);
}
/* Clean up after RCU barrier testing. */
{
int i;
- if (barrier_task != NULL) {
- VERBOSE_PRINTK_STRING("Stopping rcu_torture_barrier task");
- kthread_stop(barrier_task);
- barrier_task = NULL;
- }
+ torture_stop_kthread(rcu_torture_barrier, barrier_task);
if (barrier_cbs_tasks != NULL) {
- for (i = 0; i < n_barrier_cbs; i++) {
- if (barrier_cbs_tasks[i] != NULL) {
- VERBOSE_PRINTK_STRING("Stopping rcu_torture_barrier_cbs task");
- kthread_stop(barrier_cbs_tasks[i]);
- barrier_cbs_tasks[i] = NULL;
- }
- }
+ for (i = 0; i < n_barrier_cbs; i++)
+ torture_stop_kthread(rcu_torture_barrier_cbs,
+ barrier_cbs_tasks[i]);
kfree(barrier_cbs_tasks);
barrier_cbs_tasks = NULL;
}
{
int i;
- mutex_lock(&fullstop_mutex);
rcutorture_record_test_transition();
- if (fullstop == FULLSTOP_SHUTDOWN) {
- pr_warn(/* but going down anyway, so... */
- "Concurrent 'rmmod rcutorture' and shutdown illegal!\n");
- mutex_unlock(&fullstop_mutex);
- schedule_timeout_uninterruptible(10);
+ if (torture_cleanup()) {
if (cur_ops->cb_barrier != NULL)
cur_ops->cb_barrier();
return;
}
- fullstop = FULLSTOP_RMMOD;
- mutex_unlock(&fullstop_mutex);
- unregister_reboot_notifier(&rcutorture_shutdown_nb);
- rcu_torture_barrier_cleanup();
- rcu_torture_stall_cleanup();
- if (stutter_task) {
- VERBOSE_PRINTK_STRING("Stopping rcu_torture_stutter task");
- kthread_stop(stutter_task);
- }
- stutter_task = NULL;
- if (shuffler_task) {
- VERBOSE_PRINTK_STRING("Stopping rcu_torture_shuffle task");
- kthread_stop(shuffler_task);
- free_cpumask_var(shuffle_tmp_mask);
- }
- shuffler_task = NULL;
- if (writer_task) {
- VERBOSE_PRINTK_STRING("Stopping rcu_torture_writer task");
- kthread_stop(writer_task);
- }
- writer_task = NULL;
+ rcu_torture_barrier_cleanup();
+ torture_stop_kthread(rcu_torture_stall, stall_task);
+ torture_stop_kthread(rcu_torture_writer, writer_task);
if (reader_tasks) {
- for (i = 0; i < nrealreaders; i++) {
- if (reader_tasks[i]) {
- VERBOSE_PRINTK_STRING(
- "Stopping rcu_torture_reader task");
- kthread_stop(reader_tasks[i]);
- }
- reader_tasks[i] = NULL;
- }
+ for (i = 0; i < nrealreaders; i++)
+ torture_stop_kthread(rcu_torture_reader,
+ reader_tasks[i]);
kfree(reader_tasks);
- reader_tasks = NULL;
}
rcu_torture_current = NULL;
if (fakewriter_tasks) {
for (i = 0; i < nfakewriters; i++) {
- if (fakewriter_tasks[i]) {
- VERBOSE_PRINTK_STRING(
- "Stopping rcu_torture_fakewriter task");
- kthread_stop(fakewriter_tasks[i]);
- }
- fakewriter_tasks[i] = NULL;
+ torture_stop_kthread(rcu_torture_fakewriter,
+ fakewriter_tasks[i]);
}
kfree(fakewriter_tasks);
fakewriter_tasks = NULL;
}
- if (stats_task) {
- VERBOSE_PRINTK_STRING("Stopping rcu_torture_stats task");
- kthread_stop(stats_task);
- }
- stats_task = NULL;
-
- if (fqs_task) {
- VERBOSE_PRINTK_STRING("Stopping rcu_torture_fqs task");
- kthread_stop(fqs_task);
- }
- fqs_task = NULL;
+ torture_stop_kthread(rcu_torture_stats, stats_task);
+ torture_stop_kthread(rcu_torture_fqs, fqs_task);
if ((test_boost == 1 && cur_ops->can_boost) ||
test_boost == 2) {
unregister_cpu_notifier(&rcutorture_cpu_nb);
for_each_possible_cpu(i)
rcutorture_booster_cleanup(i);
}
- if (shutdown_task != NULL) {
- VERBOSE_PRINTK_STRING("Stopping rcu_torture_shutdown task");
- kthread_stop(shutdown_task);
- }
- shutdown_task = NULL;
- rcu_torture_onoff_cleanup();
/* Wait for all RCU callbacks to fire. */
if (atomic_read(&n_rcu_torture_error) || n_rcu_torture_barrier_error)
rcu_torture_print_module_parms(cur_ops, "End of test: FAILURE");
- else if (n_online_successes != n_online_attempts ||
- n_offline_successes != n_offline_attempts)
+ else if (torture_onoff_failures())
rcu_torture_print_module_parms(cur_ops,
"End of test: RCU_HOTPLUG");
else
int i;
int cpu;
int firsterr = 0;
- int retval;
static struct rcu_torture_ops *torture_ops[] = {
- &rcu_ops, &rcu_bh_ops, &srcu_ops, &sched_ops,
+ &rcu_ops, &rcu_bh_ops, &rcu_busted_ops, &srcu_ops, &sched_ops,
};
- mutex_lock(&fullstop_mutex);
+ torture_init_begin(torture_type, verbose, &rcutorture_runnable);
/* Process args and tell the world that the torturer is on the job. */
for (i = 0; i < ARRAY_SIZE(torture_ops); i++) {
for (i = 0; i < ARRAY_SIZE(torture_ops); i++)
pr_alert(" %s", torture_ops[i]->name);
pr_alert("\n");
- mutex_unlock(&fullstop_mutex);
+ torture_init_end();
return -EINVAL;
}
if (cur_ops->fqs == NULL && fqs_duration != 0) {
else
nrealreaders = 2 * num_online_cpus();
rcu_torture_print_module_parms(cur_ops, "Start of test");
- fullstop = FULLSTOP_DONTSTOP;
/* Set up the freelist. */
/* Start up the kthreads. */
- VERBOSE_PRINTK_STRING("Creating rcu_torture_writer task");
- writer_task = kthread_create(rcu_torture_writer, NULL,
- "rcu_torture_writer");
- if (IS_ERR(writer_task)) {
- firsterr = PTR_ERR(writer_task);
- VERBOSE_PRINTK_ERRSTRING("Failed to create writer");
- writer_task = NULL;
+ firsterr = torture_create_kthread(rcu_torture_writer, NULL,
+ writer_task);
+ if (firsterr)
goto unwind;
- }
- wake_up_process(writer_task);
fakewriter_tasks = kzalloc(nfakewriters * sizeof(fakewriter_tasks[0]),
GFP_KERNEL);
if (fakewriter_tasks == NULL) {
- VERBOSE_PRINTK_ERRSTRING("out of memory");
+ VERBOSE_TOROUT_ERRSTRING("out of memory");
firsterr = -ENOMEM;
goto unwind;
}
for (i = 0; i < nfakewriters; i++) {
- VERBOSE_PRINTK_STRING("Creating rcu_torture_fakewriter task");
- fakewriter_tasks[i] = kthread_run(rcu_torture_fakewriter, NULL,
- "rcu_torture_fakewriter");
- if (IS_ERR(fakewriter_tasks[i])) {
- firsterr = PTR_ERR(fakewriter_tasks[i]);
- VERBOSE_PRINTK_ERRSTRING("Failed to create fakewriter");
- fakewriter_tasks[i] = NULL;
+ firsterr = torture_create_kthread(rcu_torture_fakewriter,
+ NULL, fakewriter_tasks[i]);
+ if (firsterr)
goto unwind;
- }
}
reader_tasks = kzalloc(nrealreaders * sizeof(reader_tasks[0]),
GFP_KERNEL);
if (reader_tasks == NULL) {
- VERBOSE_PRINTK_ERRSTRING("out of memory");
+ VERBOSE_TOROUT_ERRSTRING("out of memory");
firsterr = -ENOMEM;
goto unwind;
}
for (i = 0; i < nrealreaders; i++) {
- VERBOSE_PRINTK_STRING("Creating rcu_torture_reader task");
- reader_tasks[i] = kthread_run(rcu_torture_reader, NULL,
- "rcu_torture_reader");
- if (IS_ERR(reader_tasks[i])) {
- firsterr = PTR_ERR(reader_tasks[i]);
- VERBOSE_PRINTK_ERRSTRING("Failed to create reader");
- reader_tasks[i] = NULL;
+ firsterr = torture_create_kthread(rcu_torture_reader, NULL,
+ reader_tasks[i]);
+ if (firsterr)
goto unwind;
- }
}
if (stat_interval > 0) {
- VERBOSE_PRINTK_STRING("Creating rcu_torture_stats task");
- stats_task = kthread_run(rcu_torture_stats, NULL,
- "rcu_torture_stats");
- if (IS_ERR(stats_task)) {
- firsterr = PTR_ERR(stats_task);
- VERBOSE_PRINTK_ERRSTRING("Failed to create stats");
- stats_task = NULL;
+ firsterr = torture_create_kthread(rcu_torture_stats, NULL,
+ stats_task);
+ if (firsterr)
goto unwind;
- }
}
if (test_no_idle_hz) {
- rcu_idle_cpu = num_online_cpus() - 1;
-
- if (!alloc_cpumask_var(&shuffle_tmp_mask, GFP_KERNEL)) {
- firsterr = -ENOMEM;
- VERBOSE_PRINTK_ERRSTRING("Failed to alloc mask");
- goto unwind;
- }
-
- /* Create the shuffler thread */
- shuffler_task = kthread_run(rcu_torture_shuffle, NULL,
- "rcu_torture_shuffle");
- if (IS_ERR(shuffler_task)) {
- free_cpumask_var(shuffle_tmp_mask);
- firsterr = PTR_ERR(shuffler_task);
- VERBOSE_PRINTK_ERRSTRING("Failed to create shuffler");
- shuffler_task = NULL;
+ firsterr = torture_shuffle_init(shuffle_interval * HZ);
+ if (firsterr)
goto unwind;
- }
}
if (stutter < 0)
stutter = 0;
if (stutter) {
- /* Create the stutter thread */
- stutter_task = kthread_run(rcu_torture_stutter, NULL,
- "rcu_torture_stutter");
- if (IS_ERR(stutter_task)) {
- firsterr = PTR_ERR(stutter_task);
- VERBOSE_PRINTK_ERRSTRING("Failed to create stutter");
- stutter_task = NULL;
+ firsterr = torture_stutter_init(stutter * HZ);
+ if (firsterr)
goto unwind;
- }
}
if (fqs_duration < 0)
fqs_duration = 0;
if (fqs_duration) {
- /* Create the stutter thread */
- fqs_task = kthread_run(rcu_torture_fqs, NULL,
- "rcu_torture_fqs");
- if (IS_ERR(fqs_task)) {
- firsterr = PTR_ERR(fqs_task);
- VERBOSE_PRINTK_ERRSTRING("Failed to create fqs");
- fqs_task = NULL;
+ /* Create the fqs thread */
+ torture_create_kthread(rcu_torture_fqs, NULL, fqs_task);
+ if (firsterr)
goto unwind;
- }
}
if (test_boost_interval < 1)
test_boost_interval = 1;
for_each_possible_cpu(i) {
if (cpu_is_offline(i))
continue; /* Heuristic: CPU can go offline. */
- retval = rcutorture_booster_init(i);
- if (retval < 0) {
- firsterr = retval;
+ firsterr = rcutorture_booster_init(i);
+ if (firsterr)
goto unwind;
- }
}
}
- if (shutdown_secs > 0) {
- shutdown_time = jiffies + shutdown_secs * HZ;
- shutdown_task = kthread_create(rcu_torture_shutdown, NULL,
- "rcu_torture_shutdown");
- if (IS_ERR(shutdown_task)) {
- firsterr = PTR_ERR(shutdown_task);
- VERBOSE_PRINTK_ERRSTRING("Failed to create shutdown");
- shutdown_task = NULL;
- goto unwind;
- }
- wake_up_process(shutdown_task);
- }
- i = rcu_torture_onoff_init();
- if (i != 0) {
- firsterr = i;
+ firsterr = torture_shutdown_init(shutdown_secs, rcu_torture_cleanup);
+ if (firsterr)
goto unwind;
- }
- register_reboot_notifier(&rcutorture_shutdown_nb);
- i = rcu_torture_stall_init();
- if (i != 0) {
- firsterr = i;
+ firsterr = torture_onoff_init(onoff_holdoff * HZ, onoff_interval * HZ);
+ if (firsterr)
goto unwind;
- }
- retval = rcu_torture_barrier_init();
- if (retval != 0) {
- firsterr = retval;
+ firsterr = rcu_torture_stall_init();
+ if (firsterr)
+ goto unwind;
+ firsterr = rcu_torture_barrier_init();
+ if (firsterr)
goto unwind;
- }
if (object_debug)
rcu_test_debug_objects();
rcutorture_record_test_transition();
- mutex_unlock(&fullstop_mutex);
+ torture_init_end();
return 0;
unwind:
- mutex_unlock(&fullstop_mutex);
+ torture_init_end();
rcu_torture_cleanup();
return firsterr;
}
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
*
* Copyright (C) IBM Corporation, 2006
* Copyright (C) Fujitsu, 2012
#include <linux/delay.h>
#include <linux/srcu.h>
-#include <trace/events/rcu.h>
-
#include "rcu.h"
/*
rcu_batch_queue(&sp->batch_queue, head);
if (!sp->running) {
sp->running = true;
- schedule_delayed_work(&sp->work, 0);
+ queue_delayed_work(system_power_efficient_wq, &sp->work, 0);
}
spin_unlock_irqrestore(&sp->queue_lock, flags);
}
}
if (pending)
- schedule_delayed_work(&sp->work, SRCU_INTERVAL);
+ queue_delayed_work(system_power_efficient_wq,
+ &sp->work, SRCU_INTERVAL);
}
/*
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
*
* Copyright IBM Corporation, 2008
*
#include <linux/prefetch.h>
#include <linux/ftrace_event.h>
-#ifdef CONFIG_RCU_TRACE
-#include <trace/events/rcu.h>
-#endif /* #else #ifdef CONFIG_RCU_TRACE */
-
#include "rcu.h"
/* Forward declarations for tiny_plugin.h. */
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
*
* Copyright (c) 2010 Linaro
*
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
*
* Copyright IBM Corporation, 2008
*
#include <linux/suspend.h>
#include "tree.h"
-#include <trace/events/rcu.h>
-
#include "rcu.h"
MODULE_ALIAS("rcutree");
* to the next. Only do this for the primary flavor of RCU.
*/
if (rdp->rsp == rcu_state &&
- ULONG_CMP_GE(ACCESS_ONCE(jiffies), rdp->rsp->jiffies_resched)) {
+ ULONG_CMP_GE(jiffies, rdp->rsp->jiffies_resched)) {
rdp->rsp->jiffies_resched += 5;
resched_cpu(rdp->cpu);
}
static void record_gp_stall_check_time(struct rcu_state *rsp)
{
- unsigned long j = ACCESS_ONCE(jiffies);
+ unsigned long j = jiffies;
unsigned long j1;
rsp->gp_start = j;
if (rcu_cpu_stall_suppress || !rcu_gp_in_progress(rsp))
return;
- j = ACCESS_ONCE(jiffies);
+ j = jiffies;
/*
* Lots of memory barriers to reject false positives.
/* Advance to a new grace period and initialize state. */
record_gp_stall_check_time(rsp);
- smp_wmb(); /* Record GP times before starting GP. */
- rsp->gpnum++;
+ /* Record GP times before starting GP, hence smp_store_release(). */
+ smp_store_release(&rsp->gpnum, rsp->gpnum + 1);
trace_rcu_grace_period(rsp->name, rsp->gpnum, TPS("start"));
raw_spin_unlock_irq(&rnp->lock);
/* Exclude any concurrent CPU-hotplug operations. */
mutex_lock(&rsp->onoff_mutex);
+ smp_mb__after_unlock_lock(); /* ->gpnum increment before GP! */
/*
* Set the quiescent-state-needed bits in all the rcu_node
}
rnp = rcu_get_root(rsp);
raw_spin_lock_irq(&rnp->lock);
- smp_mb__after_unlock_lock();
+ smp_mb__after_unlock_lock(); /* Order GP before ->completed update. */
rcu_nocb_gp_set(rnp, nocb);
- rsp->completed = rsp->gpnum; /* Declare grace period done. */
+ /* Declare grace period done. */
+ ACCESS_ONCE(rsp->completed) = rsp->gpnum;
trace_rcu_grace_period(rsp->name, rsp->completed, TPS("end"));
rsp->fqs_state = RCU_GP_IDLE;
rdp = this_cpu_ptr(rsp->rda);
if (rnp_old != NULL)
raw_spin_unlock(&rnp_old->fqslock);
if (ret) {
- rsp->n_force_qs_lh++;
+ ACCESS_ONCE(rsp->n_force_qs_lh)++;
return;
}
rnp_old = rnp;
smp_mb__after_unlock_lock();
raw_spin_unlock(&rnp_old->fqslock);
if (ACCESS_ONCE(rsp->gp_flags) & RCU_GP_FLAG_FQS) {
- rsp->n_force_qs_lh++;
+ ACCESS_ONCE(rsp->n_force_qs_lh)++;
raw_spin_unlock_irqrestore(&rnp_old->lock, flags);
return; /* Someone beat us to it. */
}
}
EXPORT_SYMBOL_GPL(synchronize_rcu_bh);
+/**
+ * get_state_synchronize_rcu - Snapshot current RCU state
+ *
+ * Returns a cookie that is used by a later call to cond_synchronize_rcu()
+ * to determine whether or not a full grace period has elapsed in the
+ * meantime.
+ */
+unsigned long get_state_synchronize_rcu(void)
+{
+ /*
+ * Any prior manipulation of RCU-protected data must happen
+ * before the load from ->gpnum.
+ */
+ smp_mb(); /* ^^^ */
+
+ /*
+ * Make sure this load happens before the purportedly
+ * time-consuming work between get_state_synchronize_rcu()
+ * and cond_synchronize_rcu().
+ */
+ return smp_load_acquire(&rcu_state->gpnum);
+}
+EXPORT_SYMBOL_GPL(get_state_synchronize_rcu);
+
+/**
+ * cond_synchronize_rcu - Conditionally wait for an RCU grace period
+ *
+ * @oldstate: return value from earlier call to get_state_synchronize_rcu()
+ *
+ * If a full RCU grace period has elapsed since the earlier call to
+ * get_state_synchronize_rcu(), just return. Otherwise, invoke
+ * synchronize_rcu() to wait for a full grace period.
+ *
+ * Yes, this function does not take counter wrap into account. But
+ * counter wrap is harmless. If the counter wraps, we have waited for
+ * more than 2 billion grace periods (and way more on a 64-bit system!),
+ * so waiting for one additional grace period should be just fine.
+ */
+void cond_synchronize_rcu(unsigned long oldstate)
+{
+ unsigned long newstate;
+
+ /*
+ * Ensure that this load happens before any RCU-destructive
+ * actions the caller might carry out after we return.
+ */
+ newstate = smp_load_acquire(&rcu_state->completed);
+ if (ULONG_CMP_GE(oldstate, newstate))
+ synchronize_rcu();
+}
+EXPORT_SYMBOL_GPL(cond_synchronize_rcu);
+
static int synchronize_sched_expedited_cpu_stop(void *data)
{
/*
* non-NULL, store an indication of whether all callbacks are lazy.
* (If there are no callbacks, all of them are deemed to be lazy.)
*/
-static int rcu_cpu_has_callbacks(int cpu, bool *all_lazy)
+static int __maybe_unused rcu_cpu_has_callbacks(int cpu, bool *all_lazy)
{
bool al = true;
bool hc = false;
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
*
* Copyright IBM Corporation, 2008
*
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
*
* Copyright Red Hat, 2009
* Copyright IBM Corporation, 2009
* Because we not have RCU_FAST_NO_HZ, just check whether this CPU needs
* any flavor of RCU.
*/
+#ifndef CONFIG_RCU_NOCB_CPU_ALL
int rcu_needs_cpu(int cpu, unsigned long *delta_jiffies)
{
*delta_jiffies = ULONG_MAX;
return rcu_cpu_has_callbacks(cpu, NULL);
}
+#endif /* #ifndef CONFIG_RCU_NOCB_CPU_ALL */
/*
* Because we do not have RCU_FAST_NO_HZ, don't bother cleaning up
* only if it has been awhile since the last time we did so. Afterwards,
* if there are any callbacks ready for immediate invocation, return true.
*/
-static bool rcu_try_advance_all_cbs(void)
+static bool __maybe_unused rcu_try_advance_all_cbs(void)
{
bool cbs_ready = false;
struct rcu_data *rdp;
*
* The caller must have disabled interrupts.
*/
+#ifndef CONFIG_RCU_NOCB_CPU_ALL
int rcu_needs_cpu(int cpu, unsigned long *dj)
{
struct rcu_dynticks *rdtp = &per_cpu(rcu_dynticks, cpu);
}
return 0;
}
+#endif /* #ifndef CONFIG_RCU_NOCB_CPU_ALL */
/*
* Prepare a CPU for idle from an RCU perspective. The first major task
*/
static void rcu_prepare_for_idle(int cpu)
{
+#ifndef CONFIG_RCU_NOCB_CPU_ALL
struct rcu_data *rdp;
struct rcu_dynticks *rdtp = &per_cpu(rcu_dynticks, cpu);
struct rcu_node *rnp;
rcu_accelerate_cbs(rsp, rnp, rdp);
raw_spin_unlock(&rnp->lock); /* irqs remain disabled. */
}
+#endif /* #ifndef CONFIG_RCU_NOCB_CPU_ALL */
}
/*
*/
static void rcu_cleanup_after_idle(int cpu)
{
-
+#ifndef CONFIG_RCU_NOCB_CPU_ALL
if (rcu_is_nocb_cpu(cpu))
return;
if (rcu_try_advance_all_cbs())
invoke_rcu_core();
+#endif /* #ifndef CONFIG_RCU_NOCB_CPU_ALL */
}
/*
init_waitqueue_head(&rnp->nocb_gp_wq[1]);
}
+#ifndef CONFIG_RCU_NOCB_CPU_ALL
/* Is the specified CPU a no-CPUs CPU? */
bool rcu_is_nocb_cpu(int cpu)
{
return cpumask_test_cpu(cpu, rcu_nocb_mask);
return false;
}
+#endif /* #ifndef CONFIG_RCU_NOCB_CPU_ALL */
/*
* Enqueue the specified string of rcu_head structures onto the specified
* CPU unless the grace period has extended for too long.
*
* This code relies on the fact that all NO_HZ_FULL CPUs are also
- * CONFIG_RCU_NOCB_CPUs.
+ * CONFIG_RCU_NOCB_CPU CPUs.
*/
static bool rcu_nohz_full_cpu(struct rcu_state *rsp)
{
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
*
* Copyright IBM Corporation, 2008
*
seq_printf(m, "nfqs=%lu/nfqsng=%lu(%lu) fqlh=%lu oqlen=%ld/%ld\n",
rsp->n_force_qs, rsp->n_force_qs_ngp,
rsp->n_force_qs - rsp->n_force_qs_ngp,
- rsp->n_force_qs_lh, rsp->qlen_lazy, rsp->qlen);
+ ACCESS_ONCE(rsp->n_force_qs_lh), rsp->qlen_lazy, rsp->qlen);
for (rnp = &rsp->node[0]; rnp - &rsp->node[0] < rcu_num_nodes; rnp++) {
if (rnp->level != level) {
seq_puts(m, "\n");
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
*
* Copyright IBM Corporation, 2001
*
#include <linux/module.h>
#define CREATE_TRACE_POINTS
-#include <trace/events/rcu.h>
#include "rcu.h"
--- /dev/null
+/*
+ * Common functions for in-kernel torture tests.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
+ *
+ * Copyright (C) IBM Corporation, 2014
+ *
+ * Author: Paul E. McKenney <paulmck@us.ibm.com>
+ * Based on kernel/rcu/torture.c.
+ */
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/kthread.h>
+#include <linux/err.h>
+#include <linux/spinlock.h>
+#include <linux/smp.h>
+#include <linux/interrupt.h>
+#include <linux/sched.h>
+#include <linux/atomic.h>
+#include <linux/bitops.h>
+#include <linux/completion.h>
+#include <linux/moduleparam.h>
+#include <linux/percpu.h>
+#include <linux/notifier.h>
+#include <linux/reboot.h>
+#include <linux/freezer.h>
+#include <linux/cpu.h>
+#include <linux/delay.h>
+#include <linux/stat.h>
+#include <linux/slab.h>
+#include <linux/trace_clock.h>
+#include <asm/byteorder.h>
+#include <linux/torture.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com>");
+
+static char *torture_type;
+static bool verbose;
+
+/* Mediate rmmod and system shutdown. Concurrent rmmod & shutdown illegal! */
+#define FULLSTOP_DONTSTOP 0 /* Normal operation. */
+#define FULLSTOP_SHUTDOWN 1 /* System shutdown with torture running. */
+#define FULLSTOP_RMMOD 2 /* Normal rmmod of torture. */
+static int fullstop = FULLSTOP_RMMOD;
+static DEFINE_MUTEX(fullstop_mutex);
+static int *torture_runnable;
+
+#ifdef CONFIG_HOTPLUG_CPU
+
+/*
+ * Variables for online-offline handling. Only present if CPU hotplug
+ * is enabled, otherwise does nothing.
+ */
+
+static struct task_struct *onoff_task;
+static long onoff_holdoff;
+static long onoff_interval;
+static long n_offline_attempts;
+static long n_offline_successes;
+static unsigned long sum_offline;
+static int min_offline = -1;
+static int max_offline;
+static long n_online_attempts;
+static long n_online_successes;
+static unsigned long sum_online;
+static int min_online = -1;
+static int max_online;
+
+/*
+ * Execute random CPU-hotplug operations at the interval specified
+ * by the onoff_interval.
+ */
+static int
+torture_onoff(void *arg)
+{
+ int cpu;
+ unsigned long delta;
+ int maxcpu = -1;
+ DEFINE_TORTURE_RANDOM(rand);
+ int ret;
+ unsigned long starttime;
+
+ VERBOSE_TOROUT_STRING("torture_onoff task started");
+ for_each_online_cpu(cpu)
+ maxcpu = cpu;
+ WARN_ON(maxcpu < 0);
+ if (onoff_holdoff > 0) {
+ VERBOSE_TOROUT_STRING("torture_onoff begin holdoff");
+ schedule_timeout_interruptible(onoff_holdoff);
+ VERBOSE_TOROUT_STRING("torture_onoff end holdoff");
+ }
+ while (!torture_must_stop()) {
+ cpu = (torture_random(&rand) >> 4) % (maxcpu + 1);
+ if (cpu_online(cpu) && cpu_is_hotpluggable(cpu)) {
+ if (verbose)
+ pr_alert("%s" TORTURE_FLAG
+ "torture_onoff task: offlining %d\n",
+ torture_type, cpu);
+ starttime = jiffies;
+ n_offline_attempts++;
+ ret = cpu_down(cpu);
+ if (ret) {
+ if (verbose)
+ pr_alert("%s" TORTURE_FLAG
+ "torture_onoff task: offline %d failed: errno %d\n",
+ torture_type, cpu, ret);
+ } else {
+ if (verbose)
+ pr_alert("%s" TORTURE_FLAG
+ "torture_onoff task: offlined %d\n",
+ torture_type, cpu);
+ n_offline_successes++;
+ delta = jiffies - starttime;
+ sum_offline += delta;
+ if (min_offline < 0) {
+ min_offline = delta;
+ max_offline = delta;
+ }
+ if (min_offline > delta)
+ min_offline = delta;
+ if (max_offline < delta)
+ max_offline = delta;
+ }
+ } else if (cpu_is_hotpluggable(cpu)) {
+ if (verbose)
+ pr_alert("%s" TORTURE_FLAG
+ "torture_onoff task: onlining %d\n",
+ torture_type, cpu);
+ starttime = jiffies;
+ n_online_attempts++;
+ ret = cpu_up(cpu);
+ if (ret) {
+ if (verbose)
+ pr_alert("%s" TORTURE_FLAG
+ "torture_onoff task: online %d failed: errno %d\n",
+ torture_type, cpu, ret);
+ } else {
+ if (verbose)
+ pr_alert("%s" TORTURE_FLAG
+ "torture_onoff task: onlined %d\n",
+ torture_type, cpu);
+ n_online_successes++;
+ delta = jiffies - starttime;
+ sum_online += delta;
+ if (min_online < 0) {
+ min_online = delta;
+ max_online = delta;
+ }
+ if (min_online > delta)
+ min_online = delta;
+ if (max_online < delta)
+ max_online = delta;
+ }
+ }
+ schedule_timeout_interruptible(onoff_interval);
+ }
+ torture_kthread_stopping("torture_onoff");
+ return 0;
+}
+
+#endif /* #ifdef CONFIG_HOTPLUG_CPU */
+
+/*
+ * Initiate online-offline handling.
+ */
+int torture_onoff_init(long ooholdoff, long oointerval)
+{
+ int ret = 0;
+
+#ifdef CONFIG_HOTPLUG_CPU
+ onoff_holdoff = ooholdoff;
+ onoff_interval = oointerval;
+ if (onoff_interval <= 0)
+ return 0;
+ ret = torture_create_kthread(torture_onoff, NULL, onoff_task);
+#endif /* #ifdef CONFIG_HOTPLUG_CPU */
+ return ret;
+}
+EXPORT_SYMBOL_GPL(torture_onoff_init);
+
+/*
+ * Clean up after online/offline testing.
+ */
+static void torture_onoff_cleanup(void)
+{
+#ifdef CONFIG_HOTPLUG_CPU
+ if (onoff_task == NULL)
+ return;
+ VERBOSE_TOROUT_STRING("Stopping torture_onoff task");
+ kthread_stop(onoff_task);
+ onoff_task = NULL;
+#endif /* #ifdef CONFIG_HOTPLUG_CPU */
+}
+EXPORT_SYMBOL_GPL(torture_onoff_cleanup);
+
+/*
+ * Print online/offline testing statistics.
+ */
+char *torture_onoff_stats(char *page)
+{
+#ifdef CONFIG_HOTPLUG_CPU
+ page += sprintf(page,
+ "onoff: %ld/%ld:%ld/%ld %d,%d:%d,%d %lu:%lu (HZ=%d) ",
+ n_online_successes, n_online_attempts,
+ n_offline_successes, n_offline_attempts,
+ min_online, max_online,
+ min_offline, max_offline,
+ sum_online, sum_offline, HZ);
+#endif /* #ifdef CONFIG_HOTPLUG_CPU */
+ return page;
+}
+EXPORT_SYMBOL_GPL(torture_onoff_stats);
+
+/*
+ * Were all the online/offline operations successful?
+ */
+bool torture_onoff_failures(void)
+{
+#ifdef CONFIG_HOTPLUG_CPU
+ return n_online_successes != n_online_attempts ||
+ n_offline_successes != n_offline_attempts;
+#else /* #ifdef CONFIG_HOTPLUG_CPU */
+ return false;
+#endif /* #else #ifdef CONFIG_HOTPLUG_CPU */
+}
+EXPORT_SYMBOL_GPL(torture_onoff_failures);
+
+#define TORTURE_RANDOM_MULT 39916801 /* prime */
+#define TORTURE_RANDOM_ADD 479001701 /* prime */
+#define TORTURE_RANDOM_REFRESH 10000
+
+/*
+ * Crude but fast random-number generator. Uses a linear congruential
+ * generator, with occasional help from cpu_clock().
+ */
+unsigned long
+torture_random(struct torture_random_state *trsp)
+{
+ if (--trsp->trs_count < 0) {
+ trsp->trs_state += (unsigned long)local_clock();
+ trsp->trs_count = TORTURE_RANDOM_REFRESH;
+ }
+ trsp->trs_state = trsp->trs_state * TORTURE_RANDOM_MULT +
+ TORTURE_RANDOM_ADD;
+ return swahw32(trsp->trs_state);
+}
+EXPORT_SYMBOL_GPL(torture_random);
+
+/*
+ * Variables for shuffling. The idea is to ensure that each CPU stays
+ * idle for an extended period to test interactions with dyntick idle,
+ * as well as interactions with any per-CPU varibles.
+ */
+struct shuffle_task {
+ struct list_head st_l;
+ struct task_struct *st_t;
+};
+
+static long shuffle_interval; /* In jiffies. */
+static struct task_struct *shuffler_task;
+static cpumask_var_t shuffle_tmp_mask;
+static int shuffle_idle_cpu; /* Force all torture tasks off this CPU */
+static struct list_head shuffle_task_list = LIST_HEAD_INIT(shuffle_task_list);
+static DEFINE_MUTEX(shuffle_task_mutex);
+
+/*
+ * Register a task to be shuffled. If there is no memory, just splat
+ * and don't bother registering.
+ */
+void torture_shuffle_task_register(struct task_struct *tp)
+{
+ struct shuffle_task *stp;
+
+ if (WARN_ON_ONCE(tp == NULL))
+ return;
+ stp = kmalloc(sizeof(*stp), GFP_KERNEL);
+ if (WARN_ON_ONCE(stp == NULL))
+ return;
+ stp->st_t = tp;
+ mutex_lock(&shuffle_task_mutex);
+ list_add(&stp->st_l, &shuffle_task_list);
+ mutex_unlock(&shuffle_task_mutex);
+}
+EXPORT_SYMBOL_GPL(torture_shuffle_task_register);
+
+/*
+ * Unregister all tasks, for example, at the end of the torture run.
+ */
+static void torture_shuffle_task_unregister_all(void)
+{
+ struct shuffle_task *stp;
+ struct shuffle_task *p;
+
+ mutex_lock(&shuffle_task_mutex);
+ list_for_each_entry_safe(stp, p, &shuffle_task_list, st_l) {
+ list_del(&stp->st_l);
+ kfree(stp);
+ }
+ mutex_unlock(&shuffle_task_mutex);
+}
+
+/* Shuffle tasks such that we allow shuffle_idle_cpu to become idle.
+ * A special case is when shuffle_idle_cpu = -1, in which case we allow
+ * the tasks to run on all CPUs.
+ */
+static void torture_shuffle_tasks(void)
+{
+ struct shuffle_task *stp;
+
+ cpumask_setall(shuffle_tmp_mask);
+ get_online_cpus();
+
+ /* No point in shuffling if there is only one online CPU (ex: UP) */
+ if (num_online_cpus() == 1) {
+ put_online_cpus();
+ return;
+ }
+
+ /* Advance to the next CPU. Upon overflow, don't idle any CPUs. */
+ shuffle_idle_cpu = cpumask_next(shuffle_idle_cpu, shuffle_tmp_mask);
+ if (shuffle_idle_cpu >= nr_cpu_ids)
+ shuffle_idle_cpu = -1;
+ if (shuffle_idle_cpu != -1) {
+ cpumask_clear_cpu(shuffle_idle_cpu, shuffle_tmp_mask);
+ if (cpumask_empty(shuffle_tmp_mask)) {
+ put_online_cpus();
+ return;
+ }
+ }
+
+ mutex_lock(&shuffle_task_mutex);
+ list_for_each_entry(stp, &shuffle_task_list, st_l)
+ set_cpus_allowed_ptr(stp->st_t, shuffle_tmp_mask);
+ mutex_unlock(&shuffle_task_mutex);
+
+ put_online_cpus();
+}
+
+/* Shuffle tasks across CPUs, with the intent of allowing each CPU in the
+ * system to become idle at a time and cut off its timer ticks. This is meant
+ * to test the support for such tickless idle CPU in RCU.
+ */
+static int torture_shuffle(void *arg)
+{
+ VERBOSE_TOROUT_STRING("torture_shuffle task started");
+ do {
+ schedule_timeout_interruptible(shuffle_interval);
+ torture_shuffle_tasks();
+ torture_shutdown_absorb("torture_shuffle");
+ } while (!torture_must_stop());
+ torture_kthread_stopping("torture_shuffle");
+ return 0;
+}
+
+/*
+ * Start the shuffler, with shuffint in jiffies.
+ */
+int torture_shuffle_init(long shuffint)
+{
+ shuffle_interval = shuffint;
+
+ shuffle_idle_cpu = -1;
+
+ if (!alloc_cpumask_var(&shuffle_tmp_mask, GFP_KERNEL)) {
+ VERBOSE_TOROUT_ERRSTRING("Failed to alloc mask");
+ return -ENOMEM;
+ }
+
+ /* Create the shuffler thread */
+ return torture_create_kthread(torture_shuffle, NULL, shuffler_task);
+}
+EXPORT_SYMBOL_GPL(torture_shuffle_init);
+
+/*
+ * Stop the shuffling.
+ */
+static void torture_shuffle_cleanup(void)
+{
+ torture_shuffle_task_unregister_all();
+ if (shuffler_task) {
+ VERBOSE_TOROUT_STRING("Stopping torture_shuffle task");
+ kthread_stop(shuffler_task);
+ free_cpumask_var(shuffle_tmp_mask);
+ }
+ shuffler_task = NULL;
+}
+EXPORT_SYMBOL_GPL(torture_shuffle_cleanup);
+
+/*
+ * Variables for auto-shutdown. This allows "lights out" torture runs
+ * to be fully scripted.
+ */
+static int shutdown_secs; /* desired test duration in seconds. */
+static struct task_struct *shutdown_task;
+static unsigned long shutdown_time; /* jiffies to system shutdown. */
+static void (*torture_shutdown_hook)(void);
+
+/*
+ * Absorb kthreads into a kernel function that won't return, so that
+ * they won't ever access module text or data again.
+ */
+void torture_shutdown_absorb(const char *title)
+{
+ while (ACCESS_ONCE(fullstop) == FULLSTOP_SHUTDOWN) {
+ pr_notice("torture thread %s parking due to system shutdown\n",
+ title);
+ schedule_timeout_uninterruptible(MAX_SCHEDULE_TIMEOUT);
+ }
+}
+EXPORT_SYMBOL_GPL(torture_shutdown_absorb);
+
+/*
+ * Cause the torture test to shutdown the system after the test has
+ * run for the time specified by the shutdown_secs parameter.
+ */
+static int torture_shutdown(void *arg)
+{
+ long delta;
+ unsigned long jiffies_snap;
+
+ VERBOSE_TOROUT_STRING("torture_shutdown task started");
+ jiffies_snap = jiffies;
+ while (ULONG_CMP_LT(jiffies_snap, shutdown_time) &&
+ !torture_must_stop()) {
+ delta = shutdown_time - jiffies_snap;
+ if (verbose)
+ pr_alert("%s" TORTURE_FLAG
+ "torture_shutdown task: %lu jiffies remaining\n",
+ torture_type, delta);
+ schedule_timeout_interruptible(delta);
+ jiffies_snap = jiffies;
+ }
+ if (torture_must_stop()) {
+ torture_kthread_stopping("torture_shutdown");
+ return 0;
+ }
+
+ /* OK, shut down the system. */
+
+ VERBOSE_TOROUT_STRING("torture_shutdown task shutting down system");
+ shutdown_task = NULL; /* Avoid self-kill deadlock. */
+ if (torture_shutdown_hook)
+ torture_shutdown_hook();
+ else
+ VERBOSE_TOROUT_STRING("No torture_shutdown_hook(), skipping.");
+ kernel_power_off(); /* Shut down the system. */
+ return 0;
+}
+
+/*
+ * Start up the shutdown task.
+ */
+int torture_shutdown_init(int ssecs, void (*cleanup)(void))
+{
+ int ret = 0;
+
+ shutdown_secs = ssecs;
+ torture_shutdown_hook = cleanup;
+ if (shutdown_secs > 0) {
+ shutdown_time = jiffies + shutdown_secs * HZ;
+ ret = torture_create_kthread(torture_shutdown, NULL,
+ shutdown_task);
+ }
+ return ret;
+}
+EXPORT_SYMBOL_GPL(torture_shutdown_init);
+
+/*
+ * Detect and respond to a system shutdown.
+ */
+static int torture_shutdown_notify(struct notifier_block *unused1,
+ unsigned long unused2, void *unused3)
+{
+ mutex_lock(&fullstop_mutex);
+ if (ACCESS_ONCE(fullstop) == FULLSTOP_DONTSTOP) {
+ VERBOSE_TOROUT_STRING("Unscheduled system shutdown detected");
+ ACCESS_ONCE(fullstop) = FULLSTOP_SHUTDOWN;
+ } else {
+ pr_warn("Concurrent rmmod and shutdown illegal!\n");
+ }
+ mutex_unlock(&fullstop_mutex);
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block torture_shutdown_nb = {
+ .notifier_call = torture_shutdown_notify,
+};
+
+/*
+ * Shut down the shutdown task. Say what??? Heh! This can happen if
+ * the torture module gets an rmmod before the shutdown time arrives. ;-)
+ */
+static void torture_shutdown_cleanup(void)
+{
+ unregister_reboot_notifier(&torture_shutdown_nb);
+ if (shutdown_task != NULL) {
+ VERBOSE_TOROUT_STRING("Stopping torture_shutdown task");
+ kthread_stop(shutdown_task);
+ }
+ shutdown_task = NULL;
+}
+
+/*
+ * Variables for stuttering, which means to periodically pause and
+ * restart testing in order to catch bugs that appear when load is
+ * suddenly applied to or removed from the system.
+ */
+static struct task_struct *stutter_task;
+static int stutter_pause_test;
+static int stutter;
+
+/*
+ * Block until the stutter interval ends. This must be called periodically
+ * by all running kthreads that need to be subject to stuttering.
+ */
+void stutter_wait(const char *title)
+{
+ while (ACCESS_ONCE(stutter_pause_test) ||
+ (torture_runnable && !ACCESS_ONCE(*torture_runnable))) {
+ if (stutter_pause_test)
+ schedule_timeout_interruptible(1);
+ else
+ schedule_timeout_interruptible(round_jiffies_relative(HZ));
+ torture_shutdown_absorb(title);
+ }
+}
+EXPORT_SYMBOL_GPL(stutter_wait);
+
+/*
+ * Cause the torture test to "stutter", starting and stopping all
+ * threads periodically.
+ */
+static int torture_stutter(void *arg)
+{
+ VERBOSE_TOROUT_STRING("torture_stutter task started");
+ do {
+ if (!torture_must_stop()) {
+ schedule_timeout_interruptible(stutter);
+ ACCESS_ONCE(stutter_pause_test) = 1;
+ }
+ if (!torture_must_stop())
+ schedule_timeout_interruptible(stutter);
+ ACCESS_ONCE(stutter_pause_test) = 0;
+ torture_shutdown_absorb("torture_stutter");
+ } while (!torture_must_stop());
+ torture_kthread_stopping("torture_stutter");
+ return 0;
+}
+
+/*
+ * Initialize and kick off the torture_stutter kthread.
+ */
+int torture_stutter_init(int s)
+{
+ int ret;
+
+ stutter = s;
+ ret = torture_create_kthread(torture_stutter, NULL, stutter_task);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(torture_stutter_init);
+
+/*
+ * Cleanup after the torture_stutter kthread.
+ */
+static void torture_stutter_cleanup(void)
+{
+ if (!stutter_task)
+ return;
+ VERBOSE_TOROUT_STRING("Stopping torture_stutter task");
+ kthread_stop(stutter_task);
+ stutter_task = NULL;
+}
+
+/*
+ * Initialize torture module. Please note that this is -not- invoked via
+ * the usual module_init() mechanism, but rather by an explicit call from
+ * the client torture module. This call must be paired with a later
+ * torture_init_end().
+ *
+ * The runnable parameter points to a flag that controls whether or not
+ * the test is currently runnable. If there is no such flag, pass in NULL.
+ */
+void __init torture_init_begin(char *ttype, bool v, int *runnable)
+{
+ mutex_lock(&fullstop_mutex);
+ torture_type = ttype;
+ verbose = v;
+ torture_runnable = runnable;
+ fullstop = FULLSTOP_DONTSTOP;
+
+}
+EXPORT_SYMBOL_GPL(torture_init_begin);
+
+/*
+ * Tell the torture module that initialization is complete.
+ */
+void __init torture_init_end(void)
+{
+ mutex_unlock(&fullstop_mutex);
+ register_reboot_notifier(&torture_shutdown_nb);
+}
+EXPORT_SYMBOL_GPL(torture_init_end);
+
+/*
+ * Clean up torture module. Please note that this is -not- invoked via
+ * the usual module_exit() mechanism, but rather by an explicit call from
+ * the client torture module. Returns true if a race with system shutdown
+ * is detected, otherwise, all kthreads started by functions in this file
+ * will be shut down.
+ *
+ * This must be called before the caller starts shutting down its own
+ * kthreads.
+ */
+bool torture_cleanup(void)
+{
+ mutex_lock(&fullstop_mutex);
+ if (ACCESS_ONCE(fullstop) == FULLSTOP_SHUTDOWN) {
+ pr_warn("Concurrent rmmod and shutdown illegal!\n");
+ mutex_unlock(&fullstop_mutex);
+ schedule_timeout_uninterruptible(10);
+ return true;
+ }
+ ACCESS_ONCE(fullstop) = FULLSTOP_RMMOD;
+ mutex_unlock(&fullstop_mutex);
+ torture_shutdown_cleanup();
+ torture_shuffle_cleanup();
+ torture_stutter_cleanup();
+ torture_onoff_cleanup();
+ return false;
+}
+EXPORT_SYMBOL_GPL(torture_cleanup);
+
+/*
+ * Is it time for the current torture test to stop?
+ */
+bool torture_must_stop(void)
+{
+ return torture_must_stop_irq() || kthread_should_stop();
+}
+EXPORT_SYMBOL_GPL(torture_must_stop);
+
+/*
+ * Is it time for the current torture test to stop? This is the irq-safe
+ * version, hence no check for kthread_should_stop().
+ */
+bool torture_must_stop_irq(void)
+{
+ return ACCESS_ONCE(fullstop) != FULLSTOP_DONTSTOP;
+}
+EXPORT_SYMBOL_GPL(torture_must_stop_irq);
+
+/*
+ * Each kthread must wait for kthread_should_stop() before returning from
+ * its top-level function, otherwise segfaults ensue. This function
+ * prints a "stopping" message and waits for kthread_should_stop(), and
+ * should be called from all torture kthreads immediately prior to
+ * returning.
+ */
+void torture_kthread_stopping(char *title)
+{
+ if (verbose)
+ VERBOSE_TOROUT_STRING(title);
+ while (!kthread_should_stop()) {
+ torture_shutdown_absorb(title);
+ schedule_timeout_uninterruptible(1);
+ }
+}
+EXPORT_SYMBOL_GPL(torture_kthread_stopping);
+
+/*
+ * Create a generic torture kthread that is immediately runnable. If you
+ * need the kthread to be stopped so that you can do something to it before
+ * it starts, you will need to open-code your own.
+ */
+int _torture_create_kthread(int (*fn)(void *arg), void *arg, char *s, char *m,
+ char *f, struct task_struct **tp)
+{
+ int ret = 0;
+
+ VERBOSE_TOROUT_STRING(m);
+ *tp = kthread_run(fn, arg, s);
+ if (IS_ERR(*tp)) {
+ ret = PTR_ERR(*tp);
+ VERBOSE_TOROUT_ERRSTRING(f);
+ *tp = NULL;
+ }
+ torture_shuffle_task_register(*tp);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(_torture_create_kthread);
+
+/*
+ * Stop a generic kthread, emitting a message.
+ */
+void _torture_stop_kthread(char *m, struct task_struct **tp)
+{
+ if (*tp == NULL)
+ return;
+ VERBOSE_TOROUT_STRING(m);
+ kthread_stop(*tp);
+ *tp = NULL;
+}
+EXPORT_SYMBOL_GPL(_torture_stop_kthread);
The following locking APIs are covered: spinlocks, rwlocks,
mutexes and rwsems.
+config LOCK_TORTURE_TEST
+ tristate "torture tests for locking"
+ depends on DEBUG_KERNEL
+ select TORTURE_TEST
+ default n
+ help
+ This option provides a kernel module that runs torture tests
+ on kernel locking primitives. The kernel module may be built
+ after the fact on the running kernel to be tested, if desired.
+
+ Say Y here if you want kernel locking-primitive torture tests
+ to be built into the kernel.
+ Say M if you want these torture tests to build as a module.
+ Say N if you are unsure.
+
endmenu # lock debugging
config TRACE_IRQFLAGS
Say N if you are unsure.
+config TORTURE_TEST
+ tristate
+ default n
+
config RCU_TORTURE_TEST
tristate "torture tests for RCU"
depends on DEBUG_KERNEL
+ select TORTURE_TEST
default n
help
This option provides a kernel module that runs torture tests
echo qemu-system-ppc64
else
echo Cannot figure out what qemu command to use! 1>&2
+ echo file $1 output: $u
# Usually this will be one of /usr/bin/qemu-system-*
# Use RCU_QEMU_CMD environment variable or appropriate
# argument to top-level script.
--- /dev/null
+#!/bin/bash
+#
+# Analyze a given results directory for locktorture progress.
+#
+# Usage: sh kvm-recheck-lock.sh resdir
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, you can access it online at
+# http://www.gnu.org/licenses/gpl-2.0.html.
+#
+# Copyright (C) IBM Corporation, 2014
+#
+# Authors: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
+
+i="$1"
+if test -d $i
+then
+ :
+else
+ echo Unreadable results directory: $i
+ exit 1
+fi
+
+configfile=`echo $i | sed -e 's/^.*\///'`
+ncs=`grep "Writes: Total:" $i/console.log 2> /dev/null | tail -1 | sed -e 's/^.* Total: //' -e 's/ .*$//'`
+if test -z "$ncs"
+then
+ echo $configfile
+else
+ title="$configfile ------- $ncs acquisitions/releases"
+ dur=`sed -e 's/^.* locktorture.shutdown_secs=//' -e 's/ .*$//' < $i/qemu-cmd 2> /dev/null`
+ if test -z "$dur"
+ then
+ :
+ else
+ ncsps=`awk -v ncs=$ncs -v dur=$dur '
+ BEGIN { print ncs / dur }' < /dev/null`
+ title="$title ($ncsps per second)"
+ fi
+ echo $title
+fi
--- /dev/null
+#!/bin/bash
+#
+# Analyze a given results directory for rcutorture progress.
+#
+# Usage: sh kvm-recheck-rcu.sh resdir
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, you can access it online at
+# http://www.gnu.org/licenses/gpl-2.0.html.
+#
+# Copyright (C) IBM Corporation, 2014
+#
+# Authors: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
+
+i="$1"
+if test -d $i
+then
+ :
+else
+ echo Unreadable results directory: $i
+ exit 1
+fi
+
+configfile=`echo $i | sed -e 's/^.*\///'`
+ngps=`grep ver: $i/console.log 2> /dev/null | tail -1 | sed -e 's/^.* ver: //' -e 's/ .*$//'`
+if test -z "$ngps"
+then
+ echo $configfile
+else
+ title="$configfile ------- $ngps grace periods"
+ dur=`sed -e 's/^.* rcutorture.shutdown_secs=//' -e 's/ .*$//' < $i/qemu-cmd 2> /dev/null`
+ if test -z "$dur"
+ then
+ :
+ else
+ ngpsps=`awk -v ngps=$ngps -v dur=$dur '
+ BEGIN { print ngps / dur }' < /dev/null`
+ title="$title ($ngpsps per second)"
+ fi
+ echo $title
+fi
#!/bin/bash
#
-# Given the results directories for previous KVM runs of rcutorture,
+# Given the results directories for previous KVM-based torture runs,
# check the build and console output for errors. Given a directory
# containing results directories, this recursively checks them all.
#
PATH=`pwd`/tools/testing/selftests/rcutorture/bin:$PATH; export PATH
for rd in "$@"
do
+ firsttime=1
dirs=`find $rd -name Make.defconfig.out -print | sort | sed -e 's,/[^/]*$,,' | sort -u`
for i in $dirs
do
- configfile=`echo $i | sed -e 's/^.*\///'`
- echo $configfile
+ if test -n "$firsttime"
+ then
+ firsttime=""
+ resdir=`echo $i | sed -e 's,/$,,' -e 's,/[^/]*$,,'`
+ head -1 $resdir/log
+ fi
+ TORTURE_SUITE="`cat $i/../TORTURE_SUITE`"
+ kvm-recheck-${TORTURE_SUITE}.sh $i
configcheck.sh $i/.config $i/ConfigFragment
parse-build.sh $i/Make.out $configfile
parse-rcutorture.sh $i/console.log $configfile
# Execute this in the source tree. Do not run it as a background task
# because qemu does not seem to like that much.
#
-# Usage: sh kvm-test-1-rcu.sh config builddir resdir minutes qemu-args bootargs
+# Usage: sh kvm-test-1-run.sh config builddir resdir minutes qemu-args boot_args
#
-# qemu-args defaults to "" -- you will want "-nographic" if running headless.
-# bootargs defaults to "root=/dev/sda noapic selinux=0 console=ttyS0"
-# "initcall_debug debug rcutorture.stat_interval=15"
-# "rcutorture.shutdown_secs=$((minutes * 60))"
-# "rcutorture.rcutorture_runnable=1"
+# qemu-args defaults to "-nographic", along with arguments specifying the
+# number of CPUs and other options generated from
+# the underlying CPU architecture.
+# boot_args defaults to value returned by the per_version_boot_params
+# shell function.
#
-# Anything you specify for either qemu-args or bootargs is appended to
+# Anything you specify for either qemu-args or boot_args is appended to
# the default values. The "-smp" value is deduced from the contents of
# the config fragment.
#
grace=120
-T=/tmp/kvm-test-1-rcu.sh.$$
+T=/tmp/kvm-test-1-run.sh.$$
trap 'rm -rf $T' 0
. $KVM/bin/functions.sh
. $KVPATH/ver_functions.sh
config_template=${1}
+config_dir=`echo $config_template | sed -e 's,/[^/]*$,,'`
title=`echo $config_template | sed -e 's/^.*\///'`
builddir=${2}
if test -z "$builddir" -o ! -d "$builddir" -o ! -w "$builddir"
then
- echo "kvm-test-1-rcu.sh :$builddir: Not a writable directory, cannot build into it"
+ echo "kvm-test-1-run.sh :$builddir: Not a writable directory, cannot build into it"
exit 1
fi
resdir=${3}
if test -z "$resdir" -o ! -d "$resdir" -o ! -w "$resdir"
then
- echo "kvm-test-1-rcu.sh :$resdir: Not a writable directory, cannot build into it"
+ echo "kvm-test-1-run.sh :$resdir: Not a writable directory, cannot store results into it"
exit 1
fi
cp $config_template $resdir/ConfigFragment
echo ' ---' `date`: Starting build
echo ' ---' Kconfig fragment at: $config_template >> $resdir/log
-cat << '___EOF___' >> $T
-CONFIG_RCU_TORTURE_TEST=y
-___EOF___
+if test -r "$config_dir/CFcommon"
+then
+ cat < $config_dir/CFcommon >> $T
+fi
# Optimizations below this point
# CONFIG_USB=n
# CONFIG_SECURITY=n
cp $builddir/.config $resdir
cp $builddir/arch/x86/boot/bzImage $resdir
parse-build.sh $resdir/Make.out $title
+ if test -f $builddir.wait
+ then
+ mv $builddir.wait $builddir.ready
+ fi
else
cp $builddir/Make*.out $resdir
echo Build failed, not running KVM, see $resdir.
+ if test -f $builddir.wait
+ then
+ mv $builddir.wait $builddir.ready
+ fi
exit 1
fi
+while test -f $builddir.ready
+do
+ sleep 1
+done
minutes=$4
seconds=$(($minutes * 60))
qemu_args=$5
echo ' ---' `date`: Starting kernel
# Determine the appropriate flavor of qemu command.
-QEMU="`identify_qemu $builddir/vmlinux.o`"
+QEMU="`identify_qemu $builddir/vmlinux`"
# Generate -smp qemu argument.
+qemu_args="-nographic $qemu_args"
cpu_count=`configNR_CPUS.sh $config_template`
vcpus=`identify_qemu_vcpus`
if test $cpu_count -gt $vcpus
# Pull in Kconfig-fragment boot parameters
boot_args="`configfrag_boot_params "$boot_args" "$config_template"`"
-# Generate CPU-hotplug boot parameters
-boot_args="`rcutorture_param_onoff "$boot_args" $builddir/.config`"
-# Generate rcu_barrier() boot parameter
-boot_args="`rcutorture_param_n_barrier_cbs "$boot_args"`"
-# Pull in standard rcutorture boot arguments
-boot_args="$boot_args rcutorture.stat_interval=15 rcutorture.shutdown_secs=$seconds rcutorture.rcutorture_runnable=1"
+# Generate kernel-version-specific boot parameters
+boot_args="`per_version_boot_params "$boot_args" $builddir/.config $seconds`"
echo $QEMU $qemu_args -m 512 -kernel $builddir/arch/x86/boot/bzImage -append \"$qemu_append $boot_args\" > $resdir/qemu-cmd
if test -n "$RCU_BUILDONLY"
fi
cp $builddir/console.log $resdir
-parse-rcutorture.sh $resdir/console.log $title
+parse-${TORTURE_SUITE}torture.sh $resdir/console.log $title
parse-console.sh $resdir/console.log $title
scriptname=$0
args="$*"
+T=/tmp/kvm.sh.$$
+trap 'rm -rf $T' 0
+mkdir $T
+
dur=30
+dryrun=""
KVM="`pwd`/tools/testing/selftests/rcutorture"; export KVM
PATH=${KVM}/bin:$PATH; export PATH
builddir="${KVM}/b1"
RCU_INITRD="$KVM/initrd"; export RCU_INITRD
RCU_KMAKE_ARG=""; export RCU_KMAKE_ARG
+TORTURE_SUITE=rcu
resdir=""
configs=""
+cpus=0
ds=`date +%Y.%m.%d-%H:%M:%S`
kversion=""
echo " --builddir absolute-pathname"
echo " --buildonly"
echo " --configs \"config-file list\""
+ echo " --cpus N"
echo " --datestamp string"
+ echo " --dryrun sched|script"
echo " --duration minutes"
echo " --interactive"
echo " --kmake-arg kernel-make-arguments"
echo " --no-initrd"
echo " --qemu-args qemu-system-..."
echo " --qemu-cmd qemu-system-..."
- echo " --results absolute-pathname"
echo " --relbuilddir relative-pathname"
+ echo " --results absolute-pathname"
+ echo " --torture rcu"
exit 1
}
configs="$2"
shift
;;
+ --cpus)
+ checkarg --cpus "(number)" "$#" "$2" '^[0-9]*$' '^--'
+ cpus=$2
+ shift
+ ;;
--datestamp)
checkarg --datestamp "(relative pathname)" "$#" "$2" '^[^/]*$' '^--'
ds=$2
shift
;;
+ --dryrun)
+ checkarg --dryrun "sched|script" $# "$2" 'sched\|script' '^--'
+ dryrun=$2
+ shift
+ ;;
--duration)
checkarg --duration "(minutes)" $# "$2" '^[0-9]*$' '^error'
dur=$2
resdir=$2
shift
;;
+ --torture)
+ checkarg --torture "(suite name)" "$#" "$2" '^\(lock\|rcu\)$' '^--'
+ TORTURE_SUITE=$2
+ shift
+ ;;
*)
echo Unknown argument $1
usage
shift
done
-CONFIGFRAG=${KVM}/configs; export CONFIGFRAG
+CONFIGFRAG=${KVM}/configs/${TORTURE_SUITE}; export CONFIGFRAG
KVPATH=${CONFIGFRAG}/$kversion; export KVPATH
if test -z "$configs"
if test -z "$resdir"
then
resdir=$KVM/res
- if ! test -e $resdir
- then
- mkdir $resdir || :
- fi
-else
+fi
+
+if test "$dryrun" = ""
+then
if ! test -e $resdir
then
mkdir -p "$resdir" || :
fi
-fi
-mkdir $resdir/$ds
-touch $resdir/$ds/log
-echo $scriptname $args >> $resdir/$ds/log
+ mkdir $resdir/$ds
-pwd > $resdir/$ds/testid.txt
-if test -d .git
-then
- git status >> $resdir/$ds/testid.txt
- git rev-parse HEAD >> $resdir/$ds/testid.txt
-fi
-builddir=$KVM/b1
-if ! test -e $builddir
-then
- mkdir $builddir || :
+ # Be noisy only if running the script.
+ echo Results directory: $resdir/$ds
+ echo $scriptname $args
+
+ touch $resdir/$ds/log
+ echo $scriptname $args >> $resdir/$ds/log
+ echo ${TORTURE_SUITE} > $resdir/$ds/TORTURE_SUITE
+
+ pwd > $resdir/$ds/testid.txt
+ if test -d .git
+ then
+ git status >> $resdir/$ds/testid.txt
+ git rev-parse HEAD >> $resdir/$ds/testid.txt
+ fi
fi
+# Create a file of test-name/#cpus pairs, sorted by decreasing #cpus.
+touch $T/cfgcpu
for CF in $configs
do
- # Running TREE01 multiple times creates TREE01, TREE01.2, TREE01.3, ...
- rd=$resdir/$ds/$CF
- if test -d "${rd}"
+ if test -f "$CONFIGFRAG/$kversion/$CF"
then
- n="`ls -d "${rd}"* | grep '\.[0-9]\+$' |
- sed -e 's/^.*\.\([0-9]\+\)/\1/' |
- sort -k1n | tail -1`"
- if test -z "$n"
- then
- rd="${rd}.2"
- else
- n="`expr $n + 1`"
- rd="${rd}.${n}"
- fi
+ echo $CF `configNR_CPUS.sh $CONFIGFRAG/$kversion/$CF` >> $T/cfgcpu
+ else
+ echo "The --configs file $CF does not exist, terminating."
+ exit 1
fi
- mkdir "${rd}"
- echo Results directory: $rd
- kvm-test-1-rcu.sh $CONFIGFRAG/$kversion/$CF $builddir $rd $dur "-nographic $RCU_QEMU_ARG" "rcutorture.test_no_idle_hz=1 rcutorture.verbose=1 $RCU_BOOTARGS"
done
+sort -k2nr $T/cfgcpu > $T/cfgcpu.sort
+
+# Use a greedy bin-packing algorithm, sorting the list accordingly.
+awk < $T/cfgcpu.sort > $T/cfgcpu.pack -v ncpus=$cpus '
+BEGIN {
+ njobs = 0;
+}
+
+{
+ # Read file of tests and corresponding required numbers of CPUs.
+ cf[njobs] = $1;
+ cpus[njobs] = $2;
+ njobs++;
+}
+
+END {
+ alldone = 0;
+ batch = 0;
+ nc = -1;
+
+ # Each pass through the following loop creates on test batch
+ # that can be executed concurrently given ncpus. Note that a
+ # given test that requires more than the available CPUs will run in
+ # their own batch. Such tests just have to make do with what
+ # is available.
+ while (nc != ncpus) {
+ batch++;
+ nc = ncpus;
+
+ # Each pass through the following loop considers one
+ # test for inclusion in the current batch.
+ for (i = 0; i < njobs; i++) {
+ if (done[i])
+ continue; # Already part of a batch.
+ if (nc >= cpus[i] || nc == ncpus) {
+
+ # This test fits into the current batch.
+ done[i] = batch;
+ nc -= cpus[i];
+ if (nc <= 0)
+ break; # Too-big test in its own batch.
+ }
+ }
+ }
+
+ # Dump out the tests in batch order.
+ for (b = 1; b <= batch; b++)
+ for (i = 0; i < njobs; i++)
+ if (done[i] == b)
+ print cf[i], cpus[i];
+}'
+
+# Generate a script to execute the tests in appropriate batches.
+cat << ___EOF___ > $T/script
+TORTURE_SUITE="$TORTURE_SUITE"; export TORTURE_SUITE
+___EOF___
+awk < $T/cfgcpu.pack \
+ -v CONFIGDIR="$CONFIGFRAG/$kversion/" \
+ -v KVM="$KVM" \
+ -v ncpus=$cpus \
+ -v rd=$resdir/$ds/ \
+ -v dur=$dur \
+ -v RCU_QEMU_ARG=$RCU_QEMU_ARG \
+ -v RCU_BOOTARGS=$RCU_BOOTARGS \
+'BEGIN {
+ i = 0;
+}
+
+{
+ cf[i] = $1;
+ cpus[i] = $2;
+ i++;
+}
+
+# Dump out the scripting required to run one test batch.
+function dump(first, pastlast)
+{
+ print "echo ----Start batch: `date`";
+ print "echo ----Start batch: `date` >> " rd "/log";
+ jn=1
+ for (j = first; j < pastlast; j++) {
+ builddir=KVM "/b" jn
+ cpusr[jn] = cpus[j];
+ if (cfrep[cf[j]] == "") {
+ cfr[jn] = cf[j];
+ cfrep[cf[j]] = 1;
+ } else {
+ cfrep[cf[j]]++;
+ cfr[jn] = cf[j] "." cfrep[cf[j]];
+ }
+ if (cpusr[jn] > ncpus && ncpus != 0)
+ ovf = "(!)";
+ else
+ ovf = "";
+ print "echo ", cfr[jn], cpusr[jn] ovf ": Starting build. `date`";
+ print "echo ", cfr[jn], cpusr[jn] ovf ": Starting build. `date` >> " rd "/log";
+ print "rm -f " builddir ".*";
+ print "touch " builddir ".wait";
+ print "mkdir " builddir " > /dev/null 2>&1 || :";
+ print "mkdir " rd cfr[jn] " || :";
+ print "kvm-test-1-run.sh " CONFIGDIR cf[j], builddir, rd cfr[jn], dur " \"" RCU_QEMU_ARG "\" \"" RCU_BOOTARGS "\" > " rd cfr[jn] "/kvm-test-1-run.sh.out 2>&1 &"
+ print "echo ", cfr[jn], cpusr[jn] ovf ": Waiting for build to complete. `date`";
+ print "echo ", cfr[jn], cpusr[jn] ovf ": Waiting for build to complete. `date` >> " rd "/log";
+ print "while test -f " builddir ".wait"
+ print "do"
+ print "\tsleep 1"
+ print "done"
+ print "echo ", cfr[jn], cpusr[jn] ovf ": Build complete. `date`";
+ print "echo ", cfr[jn], cpusr[jn] ovf ": Build complete. `date` >> " rd "/log";
+ jn++;
+ }
+ for (j = 1; j < jn; j++) {
+ builddir=KVM "/b" j
+ print "rm -f " builddir ".ready"
+ print "echo ----", cfr[j], cpusr[j] ovf ": Starting kernel. `date`";
+ print "echo ----", cfr[j], cpusr[j] ovf ": Starting kernel. `date` >> " rd "/log";
+ }
+ print "wait"
+ print "echo ---- All kernel runs complete. `date`";
+ print "echo ---- All kernel runs complete. `date` >> " rd "/log";
+ for (j = 1; j < jn; j++) {
+ builddir=KVM "/b" j
+ print "echo ----", cfr[j], cpusr[j] ovf ": Build/run results:";
+ print "echo ----", cfr[j], cpusr[j] ovf ": Build/run results: >> " rd "/log";
+ print "cat " rd cfr[j] "/kvm-test-1-run.sh.out";
+ print "cat " rd cfr[j] "/kvm-test-1-run.sh.out >> " rd "/log";
+ }
+}
+
+END {
+ njobs = i;
+ nc = ncpus;
+ first = 0;
+
+ # Each pass through the following loop considers one test.
+ for (i = 0; i < njobs; i++) {
+ if (ncpus == 0) {
+ # Sequential test specified, each test its own batch.
+ dump(i, i + 1);
+ first = i;
+ } else if (nc < cpus[i] && i != 0) {
+ # Out of CPUs, dump out a batch.
+ dump(first, i);
+ first = i;
+ nc = ncpus;
+ }
+ # Account for the CPUs needed by the current test.
+ nc -= cpus[i];
+ }
+ # Dump the last batch.
+ if (ncpus != 0)
+ dump(first, i);
+}' >> $T/script
+
+if test "$dryrun" = script
+then
+ # Dump out the script, but define the environment variables that
+ # it needs to run standalone.
+ echo CONFIGFRAG="$CONFIGFRAG; export CONFIGFRAG"
+ echo KVM="$KVM; export KVM"
+ echo KVPATH="$KVPATH; export KVPATH"
+ echo PATH="$PATH; export PATH"
+ echo RCU_BUILDONLY="$RCU_BUILDONLY; export RCU_BUILDONLY"
+ echo RCU_INITRD="$RCU_INITRD; export RCU_INITRD"
+ echo RCU_KMAKE_ARG="$RCU_KMAKE_ARG; export RCU_KMAKE_ARG"
+ echo RCU_QEMU_CMD="$RCU_QEMU_CMD; export RCU_QEMU_CMD"
+ echo RCU_QEMU_INTERACTIVE="$RCU_QEMU_INTERACTIVE; export RCU_QEMU_INTERACTIVE"
+ echo RCU_QEMU_MAC="$RCU_QEMU_MAC; export RCU_QEMU_MAC"
+ echo "mkdir -p "$resdir" || :"
+ echo "mkdir $resdir/$ds"
+ cat $T/script
+ exit 0
+elif test "$dryrun" = sched
+then
+ # Extract the test run schedule from the script.
+ egrep 'start batch|Starting build\.' $T/script |
+ sed -e 's/:.*$//' -e 's/^echo //'
+ exit 0
+else
+ # Not a dryru, so run the script.
+ sh $T/script
+fi
+
# Tracing: trace_event=rcu:rcu_grace_period,rcu:rcu_future_grace_period,rcu:rcu_grace_period_init,rcu:rcu_nocb_wake,rcu:rcu_preempt_task,rcu:rcu_unlock_preempted_task,rcu:rcu_quiescent_state_report,rcu:rcu_fqs,rcu:rcu_callback,rcu:rcu_kfree_callback,rcu:rcu_batch_start,rcu:rcu_invoke_callback,rcu:rcu_invoke_kfree_callback,rcu:rcu_batch_end,rcu:rcu_torture_read,rcu:rcu_barrier
+echo
+echo
echo " --- `date` Test summary:"
+echo Results directory: $resdir/$ds
kvm-recheck.sh $resdir/$ds
--- /dev/null
+CONFIG_SMP=y
+CONFIG_NR_CPUS=4
+CONFIG_HOTPLUG_CPU=y
+CONFIG_PREEMPT_NONE=n
+CONFIG_PREEMPT_VOLUNTARY=n
+CONFIG_PREEMPT=y
--- /dev/null
+locktorture.torture_type=lock_busted
--- /dev/null
+CONFIG_LOCK_TORTURE_TEST=y
+CONFIG_PRINTK_TIME=y
--- /dev/null
+CONFIG_SMP=y
+CONFIG_NR_CPUS=8
+CONFIG_HOTPLUG_CPU=y
+CONFIG_PREEMPT_NONE=n
+CONFIG_PREEMPT_VOLUNTARY=n
+CONFIG_PREEMPT=y
--- /dev/null
+#!/bin/bash
+#
+# Kernel-version-dependent shell functions for the rest of the scripts.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, you can access it online at
+# http://www.gnu.org/licenses/gpl-2.0.html.
+#
+# Copyright (C) IBM Corporation, 2014
+#
+# Authors: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
+
+# locktorture_param_onoff bootparam-string config-file
+#
+# Adds onoff locktorture module parameters to kernels having it.
+locktorture_param_onoff () {
+ if ! bootparam_hotplug_cpu "$1" && configfrag_hotplug_cpu "$2"
+ then
+ echo CPU-hotplug kernel, adding locktorture onoff. 1>&2
+ echo locktorture.onoff_interval=3 locktorture.onoff_holdoff=30
+ fi
+}
+
+# per_version_boot_params bootparam-string config-file seconds
+#
+# Adds per-version torture-module parameters to kernels supporting them.
+per_version_boot_params () {
+ echo $1 `locktorture_param_onoff "$1" "$2"` \
+ locktorture.stat_interval=15 \
+ locktorture.shutdown_secs=$3 \
+ locktorture.locktorture_runnable=1 \
+ locktorture.verbose=1
+}
--- /dev/null
+CONFIG_RCU_TRACE=n
+CONFIG_SMP=y
+CONFIG_NR_CPUS=4
+CONFIG_HOTPLUG_CPU=y
+CONFIG_PREEMPT_NONE=n
+CONFIG_PREEMPT_VOLUNTARY=n
+CONFIG_PREEMPT=y
--- /dev/null
+rcutorture.torture_type=rcu_busted
--- /dev/null
+CONFIG_RCU_TORTURE_TEST=y
+CONFIG_PRINTK_TIME=y
CONFIG_RCU_TRACE=n
CONFIG_SMP=y
-CONFIG_NR_CPUS=8
+CONFIG_NR_CPUS=4
CONFIG_HOTPLUG_CPU=y
CONFIG_PREEMPT_NONE=y
CONFIG_PREEMPT_VOLUNTARY=n
CONFIG_PREEMPT=n
-CONFIG_PRINTK_TIME=y
CONFIG_PREEMPT_NONE=n
CONFIG_PREEMPT_VOLUNTARY=n
CONFIG_PREEMPT=y
-CONFIG_PRINTK_TIME=y
CONFIG_DEBUG_LOCK_ALLOC=n
CONFIG_DEBUG_OBJECTS_RCU_HEAD=n
CONFIG_PREEMPT_COUNT=n
-CONFIG_PRINTK_TIME=y
CONFIG_DEBUG_LOCK_ALLOC=y
CONFIG_DEBUG_OBJECTS_RCU_HEAD=n
CONFIG_PREEMPT_COUNT=y
-CONFIG_PRINTK_TIME=y
CONFIG_RCU_CPU_STALL_VERBOSE=n
CONFIG_RCU_BOOST=n
CONFIG_DEBUG_OBJECTS_RCU_HEAD=n
-CONFIG_PRINTK_TIME=y
CONFIG_HZ_PERIODIC=n
CONFIG_NO_HZ_IDLE=y
CONFIG_NO_HZ_FULL=n
-CONFIG_RCU_FAST_NO_HZ=n
+CONFIG_RCU_FAST_NO_HZ=n
CONFIG_RCU_TRACE=n
CONFIG_HOTPLUG_CPU=n
CONFIG_SUSPEND=n
CONFIG_RCU_CPU_STALL_VERBOSE=y
CONFIG_RCU_BOOST=n
CONFIG_DEBUG_OBJECTS_RCU_HEAD=n
-CONFIG_PRINTK_TIME=y
CONFIG_RCU_BOOST=y
CONFIG_RCU_BOOST_PRIO=2
CONFIG_DEBUG_OBJECTS_RCU_HEAD=n
-CONFIG_PRINTK_TIME=y
CONFIG_RCU_CPU_STALL_INFO=y
CONFIG_RCU_CPU_STALL_VERBOSE=y
CONFIG_DEBUG_OBJECTS_RCU_HEAD=n
-CONFIG_PRINTK_TIME=y
CONFIG_RCU_CPU_STALL_INFO=n
CONFIG_RCU_CPU_STALL_VERBOSE=n
CONFIG_DEBUG_OBJECTS_RCU_HEAD=n
-CONFIG_PRINTK_TIME=y
CONFIG_RCU_CPU_STALL_INFO=n
CONFIG_RCU_CPU_STALL_VERBOSE=n
CONFIG_DEBUG_OBJECTS_RCU_HEAD=y
-CONFIG_PRINTK_TIME=y
CONFIG_RCU_CPU_STALL_INFO=y
CONFIG_RCU_CPU_STALL_VERBOSE=n
CONFIG_DEBUG_OBJECTS_RCU_HEAD=n
-CONFIG_PRINTK_TIME=y
CONFIG_RCU_CPU_STALL_VERBOSE=n
CONFIG_RCU_BOOST=n
CONFIG_DEBUG_OBJECTS_RCU_HEAD=n
-CONFIG_PRINTK_TIME=y
CONFIG_RCU_CPU_STALL_VERBOSE=n
CONFIG_RCU_BOOST=n
CONFIG_DEBUG_OBJECTS_RCU_HEAD=n
-CONFIG_PRINTK_TIME=y
CONFIG_RCU_CPU_STALL_VERBOSE=n
CONFIG_RCU_BOOST=n
CONFIG_DEBUG_OBJECTS_RCU_HEAD=n
-CONFIG_PRINTK_TIME=y
#
# Authors: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
-# rcutorture_param_n_barrier_cbs bootparam-string
-#
-# Adds n_barrier_cbs rcutorture module parameter to kernels having it.
-rcutorture_param_n_barrier_cbs () {
- echo $1
-}
-
-# rcutorture_param_onoff bootparam-string config-file
-#
-# Adds onoff rcutorture module parameters to kernels having it.
-rcutorture_param_onoff () {
- echo $1
+# per_version_boot_params bootparam-string config-file seconds
+#
+# Adds per-version torture-module parameters to kernels supporting them.
+# Which old kernels do not.
+per_version_boot_params () {
+ echo rcutorture.stat_interval=15 \
+ rcutorture.shutdown_secs=$3 \
+ rcutorture.rcutorture_runnable=1 \
+ rcutorture.test_no_idle_hz=1 \
+ rcutorture.verbose=1
}
#
# Authors: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
-# rcutorture_param_n_barrier_cbs bootparam-string
-#
-# Adds n_barrier_cbs rcutorture module parameter to kernels having it.
-rcutorture_param_n_barrier_cbs () {
- if echo $1 | grep -q "rcutorture\.n_barrier_cbs"
- then
- echo $1
- else
- echo $1 rcutorture.n_barrier_cbs=4
- fi
-}
-
# rcutorture_param_onoff bootparam-string config-file
#
# Adds onoff rcutorture module parameters to kernels having it.
if ! bootparam_hotplug_cpu "$1" && configfrag_hotplug_cpu "$2"
then
echo CPU-hotplug kernel, adding rcutorture onoff. 1>&2
- echo $1 rcutorture.onoff_interval=3 rcutorture.onoff_holdoff=30
- else
- echo $1
+ echo rcutorture.onoff_interval=3 rcutorture.onoff_holdoff=30
fi
}
+
+# per_version_boot_params bootparam-string config-file seconds
+#
+# Adds per-version torture-module parameters to kernels supporting them.
+per_version_boot_params () {
+ echo $1 `rcutorture_param_onoff "$1" "$2"` \
+ rcutorture.stat_interval=15 \
+ rcutorture.shutdown_secs=$3 \
+ rcutorture.rcutorture_runnable=1 \
+ rcutorture.test_no_idle_hz=1 \
+ rcutorture.verbose=1
+}
rcutorture_param_n_barrier_cbs () {
if echo $1 | grep -q "rcutorture\.n_barrier_cbs"
then
- echo $1
+ :
else
- echo $1 rcutorture.n_barrier_cbs=4
+ echo rcutorture.n_barrier_cbs=4
fi
}
rcutorture_param_onoff () {
if ! bootparam_hotplug_cpu "$1" && configfrag_hotplug_cpu "$2"
then
- echo CPU-hotplug kernel, adding rcutorture onoff.
- echo $1 rcutorture.onoff_interval=3 rcutorture.onoff_holdoff=30
- else
- echo $1
+ echo CPU-hotplug kernel, adding rcutorture onoff. 1>&2
+ echo rcutorture.onoff_interval=3 rcutorture.onoff_holdoff=30
fi
}
+
+# per_version_boot_params bootparam-string config-file seconds
+#
+# Adds per-version torture-module parameters to kernels supporting them.
+per_version_boot_params () {
+ echo $1 `rcutorture_param_onoff "$1" "$2"` \
+ `rcutorture_param_n_barrier_cbs "$1"` \
+ rcutorture.stat_interval=15 \
+ rcutorture.shutdown_secs=$3 \
+ rcutorture.rcutorture_runnable=1 \
+ rcutorture.test_no_idle_hz=1 \
+ rcutorture.verbose=1
+}
#
# Adds n_barrier_cbs rcutorture module parameter to kernels having it.
rcutorture_param_n_barrier_cbs () {
- echo $1
+ if echo $1 | grep -q "rcutorture\.n_barrier_cbs"
+ then
+ :
+ else
+ echo rcutorture.n_barrier_cbs=4
+ fi
}
# rcutorture_param_onoff bootparam-string config-file
rcutorture_param_onoff () {
if ! bootparam_hotplug_cpu "$1" && configfrag_hotplug_cpu "$2"
then
- echo CPU-hotplug kernel, adding rcutorture onoff.
- echo $1 rcutorture.onoff_interval=3 rcutorture.onoff_holdoff=30
- else
- echo $1
+ echo CPU-hotplug kernel, adding rcutorture onoff. 1>&2
+ echo rcutorture.onoff_interval=3 rcutorture.onoff_holdoff=30
fi
}
+
+# per_version_boot_params bootparam-string config-file seconds
+#
+# Adds per-version torture-module parameters to kernels supporting them.
+per_version_boot_params () {
+ echo $1 `rcutorture_param_onoff "$1" "$2"` \
+ `rcutorture_param_n_barrier_cbs "$1"` \
+ rcutorture.stat_interval=15 \
+ rcutorture.shutdown_secs=$3 \
+ rcutorture.rcutorture_runnable=1 \
+ rcutorture.test_no_idle_hz=1 \
+ rcutorture.verbose=1
+}
projects / karo-tx-linux.git / commitdiff