Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  powerpc: Fix unpaired __trace_hcall_entry and __trace_hcall_exit
  powerpc: Fix RCU idle and hcall tracing

diff --git a/arch/powerpc/kernel/idle.c b/arch/powerpc/kernel/idle.c
index 7c66ce13da89ff793a2ea18fa0e8d5b5448da41d..0a48bf5db6c84bfbf0152a9b3c52e83b9f43646d 100644 (file)
--- a/arch/powerpc/kernel/idle.c
+++ b/arch/powerpc/kernel/idle.c
@@ -50,12 +50,6 @@ static int __init powersave_off(char *arg)
 }
 __setup("powersave=off", powersave_off);
 
-#if defined(CONFIG_PPC_PSERIES) && defined(CONFIG_TRACEPOINTS)
-static const bool idle_uses_rcu = 1;
-#else
-static const bool idle_uses_rcu;
-#endif
-
 /*
  * The body of the idle task.
  */
@@ -67,8 +61,7 @@ void cpu_idle(void)
        set_thread_flag(TIF_POLLING_NRFLAG);
        while (1) {
                tick_nohz_idle_enter();
-               if (!idle_uses_rcu)
-                       rcu_idle_enter();
+               rcu_idle_enter();
 
                while (!need_resched() && !cpu_should_die()) {
                        ppc64_runlatch_off();
@@ -106,8 +99,7 @@ void cpu_idle(void)
 
                HMT_medium();
                ppc64_runlatch_on();
-               if (!idle_uses_rcu)
-                       rcu_idle_exit();
+               rcu_idle_exit();
                tick_nohz_idle_exit();
                preempt_enable_no_resched();
                if (cpu_should_die())

diff --git a/arch/powerpc/platforms/pseries/hvCall.S b/arch/powerpc/platforms/pseries/hvCall.S
index fd05fdee576a8d13af9c1ce748754747478d56ec..3ce73d0052b17a2b2e934af3daf33499d0afd4ac 100644 (file)
--- a/arch/powerpc/platforms/pseries/hvCall.S
+++ b/arch/powerpc/platforms/pseries/hvCall.S
@@ -36,6 +36,7 @@ BEGIN_FTR_SECTION;                                            \
        b       1f;                                             \
 END_FTR_SECTION(0, 1);                                         \
        ld      r12,hcall_tracepoint_refcount@toc(r2);          \
+       std     r12,32(r1);                                     \
        cmpdi   r12,0;                                          \
        beq+    1f;                                             \
        mflr    r0;                                             \
@@ -74,7 +75,7 @@ END_FTR_SECTION(0, 1);                                                \
 BEGIN_FTR_SECTION;                                             \
        b       1f;                                             \
 END_FTR_SECTION(0, 1);                                         \
-       ld      r12,hcall_tracepoint_refcount@toc(r2);          \
+       ld      r12,32(r1);                                     \
        cmpdi   r12,0;                                          \
        beq+    1f;                                             \
        mflr    r0;                                             \

diff --git a/arch/powerpc/platforms/pseries/lpar.c b/arch/powerpc/platforms/pseries/lpar.c
index 948e0e3b3547a28624b0a524b2b0de54eccd9460..7bc73af6c7b9e875f489563192866a2a8abbfea3 100644 (file)
--- a/arch/powerpc/platforms/pseries/lpar.c
+++ b/arch/powerpc/platforms/pseries/lpar.c
@@ -546,6 +546,13 @@ void __trace_hcall_entry(unsigned long opcode, unsigned long *args)
        unsigned long flags;
        unsigned int *depth;
 
+       /*
+        * We cannot call tracepoints inside RCU idle regions which
+        * means we must not trace H_CEDE.
+        */
+       if (opcode == H_CEDE)
+               return;
+
        local_irq_save(flags);
 
        depth = &__get_cpu_var(hcall_trace_depth);
@@ -556,8 +563,6 @@ void __trace_hcall_entry(unsigned long opcode, unsigned long *args)
        (*depth)++;
        preempt_disable();
        trace_hcall_entry(opcode, args);
-       if (opcode == H_CEDE)
-               rcu_idle_enter();
        (*depth)--;
 
 out:
@@ -570,6 +575,9 @@ void __trace_hcall_exit(long opcode, unsigned long retval,
        unsigned long flags;
        unsigned int *depth;
 
+       if (opcode == H_CEDE)
+               return;
+
        local_irq_save(flags);
 
        depth = &__get_cpu_var(hcall_trace_depth);
@@ -578,8 +586,6 @@ void __trace_hcall_exit(long opcode, unsigned long retval,
                goto out;
 
        (*depth)++;
-       if (opcode == H_CEDE)
-               rcu_idle_exit();
        trace_hcall_exit(opcode, retval, retbuf);
        preempt_enable();
        (*depth)--;