#include <linux/kthread.h>
#include <linux/tracefs.h>
#include <linux/uaccess.h>
+#include <linux/bsearch.h>
#include <linux/module.h>
#include <linux/ctype.h>
+#include <linux/sort.h>
#include <linux/slab.h>
#include <linux/delay.h>
+#include <trace/events/sched.h>
+
#include <asm/setup.h>
#include "trace_output.h"
static struct kmem_cache *field_cachep;
static struct kmem_cache *file_cachep;
-#define SYSTEM_FL_FREE_NAME (1 << 31)
-
static inline int system_refcount(struct event_subsystem *system)
{
- return system->ref_count & ~SYSTEM_FL_FREE_NAME;
+ return system->ref_count;
}
static int system_refcount_inc(struct event_subsystem *system)
{
- return (system->ref_count++) & ~SYSTEM_FL_FREE_NAME;
+ return system->ref_count++;
}
static int system_refcount_dec(struct event_subsystem *system)
{
- return (--system->ref_count) & ~SYSTEM_FL_FREE_NAME;
+ return --system->ref_count;
}
/* Double loops, do not use break, only goto's work */
}
EXPORT_SYMBOL_GPL(trace_event_raw_init);
+bool trace_event_ignore_this_pid(struct trace_event_file *trace_file)
+{
+ struct trace_array *tr = trace_file->tr;
+ struct trace_array_cpu *data;
+ struct trace_pid_list *pid_list;
+
+ pid_list = rcu_dereference_sched(tr->filtered_pids);
+ if (!pid_list)
+ return false;
+
+ data = this_cpu_ptr(tr->trace_buffer.data);
+
+ return data->ignore_pid;
+}
+EXPORT_SYMBOL_GPL(trace_event_ignore_this_pid);
+
void *trace_event_buffer_reserve(struct trace_event_buffer *fbuffer,
struct trace_event_file *trace_file,
unsigned long len)
{
struct trace_event_call *event_call = trace_file->event_call;
+ if ((trace_file->flags & EVENT_FILE_FL_PID_FILTER) &&
+ trace_event_ignore_this_pid(trace_file))
+ return NULL;
+
local_save_flags(fbuffer->flags);
fbuffer->pc = preempt_count();
fbuffer->trace_file = trace_file;
int enable, int soft_disable)
{
struct trace_event_call *call = file->event_call;
+ struct trace_array *tr = file->tr;
int ret = 0;
int disable;
if (soft_disable)
set_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags);
- if (trace_flags & TRACE_ITER_RECORD_CMD) {
+ if (tr->trace_flags & TRACE_ITER_RECORD_CMD) {
tracing_start_cmdline_record();
set_bit(EVENT_FILE_FL_RECORDED_CMD_BIT, &file->flags);
}
mutex_unlock(&event_mutex);
}
+static int cmp_pid(const void *key, const void *elt)
+{
+ const pid_t *search_pid = key;
+ const pid_t *pid = elt;
+
+ if (*search_pid == *pid)
+ return 0;
+ if (*search_pid < *pid)
+ return -1;
+ return 1;
+}
+
+static bool
+check_ignore_pid(struct trace_pid_list *filtered_pids, struct task_struct *task)
+{
+ pid_t search_pid;
+ pid_t *pid;
+
+ /*
+ * Return false, because if filtered_pids does not exist,
+ * all pids are good to trace.
+ */
+ if (!filtered_pids)
+ return false;
+
+ search_pid = task->pid;
+
+ pid = bsearch(&search_pid, filtered_pids->pids,
+ filtered_pids->nr_pids, sizeof(pid_t),
+ cmp_pid);
+ if (!pid)
+ return true;
+
+ return false;
+}
+
+static void
+event_filter_pid_sched_switch_probe_pre(void *data, bool preempt,
+ struct task_struct *prev, struct task_struct *next)
+{
+ struct trace_array *tr = data;
+ struct trace_pid_list *pid_list;
+
+ pid_list = rcu_dereference_sched(tr->filtered_pids);
+
+ this_cpu_write(tr->trace_buffer.data->ignore_pid,
+ check_ignore_pid(pid_list, prev) &&
+ check_ignore_pid(pid_list, next));
+}
+
+static void
+event_filter_pid_sched_switch_probe_post(void *data, bool preempt,
+ struct task_struct *prev, struct task_struct *next)
+{
+ struct trace_array *tr = data;
+ struct trace_pid_list *pid_list;
+
+ pid_list = rcu_dereference_sched(tr->filtered_pids);
+
+ this_cpu_write(tr->trace_buffer.data->ignore_pid,
+ check_ignore_pid(pid_list, next));
+}
+
+static void
+event_filter_pid_sched_wakeup_probe_pre(void *data, struct task_struct *task)
+{
+ struct trace_array *tr = data;
+ struct trace_pid_list *pid_list;
+
+ /* Nothing to do if we are already tracing */
+ if (!this_cpu_read(tr->trace_buffer.data->ignore_pid))
+ return;
+
+ pid_list = rcu_dereference_sched(tr->filtered_pids);
+
+ this_cpu_write(tr->trace_buffer.data->ignore_pid,
+ check_ignore_pid(pid_list, task));
+}
+
+static void
+event_filter_pid_sched_wakeup_probe_post(void *data, struct task_struct *task)
+{
+ struct trace_array *tr = data;
+ struct trace_pid_list *pid_list;
+
+ /* Nothing to do if we are not tracing */
+ if (this_cpu_read(tr->trace_buffer.data->ignore_pid))
+ return;
+
+ pid_list = rcu_dereference_sched(tr->filtered_pids);
+
+ /* Set tracing if current is enabled */
+ this_cpu_write(tr->trace_buffer.data->ignore_pid,
+ check_ignore_pid(pid_list, current));
+}
+
+static void __ftrace_clear_event_pids(struct trace_array *tr)
+{
+ struct trace_pid_list *pid_list;
+ struct trace_event_file *file;
+ int cpu;
+
+ pid_list = rcu_dereference_protected(tr->filtered_pids,
+ lockdep_is_held(&event_mutex));
+ if (!pid_list)
+ return;
+
+ unregister_trace_sched_switch(event_filter_pid_sched_switch_probe_pre, tr);
+ unregister_trace_sched_switch(event_filter_pid_sched_switch_probe_post, tr);
+
+ unregister_trace_sched_wakeup(event_filter_pid_sched_wakeup_probe_pre, tr);
+ unregister_trace_sched_wakeup(event_filter_pid_sched_wakeup_probe_post, tr);
+
+ list_for_each_entry(file, &tr->events, list) {
+ clear_bit(EVENT_FILE_FL_PID_FILTER_BIT, &file->flags);
+ }
+
+ for_each_possible_cpu(cpu)
+ per_cpu_ptr(tr->trace_buffer.data, cpu)->ignore_pid = false;
+
+ rcu_assign_pointer(tr->filtered_pids, NULL);
+
+ /* Wait till all users are no longer using pid filtering */
+ synchronize_sched();
+
+ free_pages((unsigned long)pid_list->pids, pid_list->order);
+ kfree(pid_list);
+}
+
+static void ftrace_clear_event_pids(struct trace_array *tr)
+{
+ mutex_lock(&event_mutex);
+ __ftrace_clear_event_pids(tr);
+ mutex_unlock(&event_mutex);
+}
+
static void __put_system(struct event_subsystem *system)
{
struct event_filter *filter = system->filter;
kfree(filter->filter_string);
kfree(filter);
}
- if (system->ref_count & SYSTEM_FL_FREE_NAME)
- kfree(system->name);
+ kfree_const(system->name);
kfree(system);
}
mutex_unlock(&event_mutex);
}
+static void *p_start(struct seq_file *m, loff_t *pos)
+ __acquires(RCU)
+{
+ struct trace_pid_list *pid_list;
+ struct trace_array *tr = m->private;
+
+ /*
+ * Grab the mutex, to keep calls to p_next() having the same
+ * tr->filtered_pids as p_start() has.
+ * If we just passed the tr->filtered_pids around, then RCU would
+ * have been enough, but doing that makes things more complex.
+ */
+ mutex_lock(&event_mutex);
+ rcu_read_lock_sched();
+
+ pid_list = rcu_dereference_sched(tr->filtered_pids);
+
+ if (!pid_list || *pos >= pid_list->nr_pids)
+ return NULL;
+
+ return (void *)&pid_list->pids[*pos];
+}
+
+static void p_stop(struct seq_file *m, void *p)
+ __releases(RCU)
+{
+ rcu_read_unlock_sched();
+ mutex_unlock(&event_mutex);
+}
+
+static void *
+p_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ struct trace_array *tr = m->private;
+ struct trace_pid_list *pid_list = rcu_dereference_sched(tr->filtered_pids);
+
+ (*pos)++;
+
+ if (*pos >= pid_list->nr_pids)
+ return NULL;
+
+ return (void *)&pid_list->pids[*pos];
+}
+
+static int p_show(struct seq_file *m, void *v)
+{
+ pid_t *pid = v;
+
+ seq_printf(m, "%d\n", *pid);
+ return 0;
+}
+
static ssize_t
event_enable_read(struct file *filp, char __user *ubuf, size_t cnt,
loff_t *ppos)
return r;
}
+static int max_pids(struct trace_pid_list *pid_list)
+{
+ return (PAGE_SIZE << pid_list->order) / sizeof(pid_t);
+}
+
+static void ignore_task_cpu(void *data)
+{
+ struct trace_array *tr = data;
+ struct trace_pid_list *pid_list;
+
+ /*
+ * This function is called by on_each_cpu() while the
+ * event_mutex is held.
+ */
+ pid_list = rcu_dereference_protected(tr->filtered_pids,
+ mutex_is_locked(&event_mutex));
+
+ this_cpu_write(tr->trace_buffer.data->ignore_pid,
+ check_ignore_pid(pid_list, current));
+}
+
+static ssize_t
+ftrace_event_pid_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ struct seq_file *m = filp->private_data;
+ struct trace_array *tr = m->private;
+ struct trace_pid_list *filtered_pids = NULL;
+ struct trace_pid_list *pid_list = NULL;
+ struct trace_event_file *file;
+ struct trace_parser parser;
+ unsigned long val;
+ loff_t this_pos;
+ ssize_t read = 0;
+ ssize_t ret = 0;
+ pid_t pid;
+ int i;
+
+ if (!cnt)
+ return 0;
+
+ ret = tracing_update_buffers();
+ if (ret < 0)
+ return ret;
+
+ if (trace_parser_get_init(&parser, EVENT_BUF_SIZE + 1))
+ return -ENOMEM;
+
+ mutex_lock(&event_mutex);
+ /*
+ * Load as many pids into the array before doing a
+ * swap from the tr->filtered_pids to the new list.
+ */
+ while (cnt > 0) {
+
+ this_pos = 0;
+
+ ret = trace_get_user(&parser, ubuf, cnt, &this_pos);
+ if (ret < 0 || !trace_parser_loaded(&parser))
+ break;
+
+ read += ret;
+ ubuf += ret;
+ cnt -= ret;
+
+ parser.buffer[parser.idx] = 0;
+
+ ret = -EINVAL;
+ if (kstrtoul(parser.buffer, 0, &val))
+ break;
+ if (val > INT_MAX)
+ break;
+
+ pid = (pid_t)val;
+
+ ret = -ENOMEM;
+ if (!pid_list) {
+ pid_list = kmalloc(sizeof(*pid_list), GFP_KERNEL);
+ if (!pid_list)
+ break;
+
+ filtered_pids = rcu_dereference_protected(tr->filtered_pids,
+ lockdep_is_held(&event_mutex));
+ if (filtered_pids)
+ pid_list->order = filtered_pids->order;
+ else
+ pid_list->order = 0;
+
+ pid_list->pids = (void *)__get_free_pages(GFP_KERNEL,
+ pid_list->order);
+ if (!pid_list->pids)
+ break;
+
+ if (filtered_pids) {
+ pid_list->nr_pids = filtered_pids->nr_pids;
+ memcpy(pid_list->pids, filtered_pids->pids,
+ pid_list->nr_pids * sizeof(pid_t));
+ } else
+ pid_list->nr_pids = 0;
+ }
+
+ if (pid_list->nr_pids >= max_pids(pid_list)) {
+ pid_t *pid_page;
+
+ pid_page = (void *)__get_free_pages(GFP_KERNEL,
+ pid_list->order + 1);
+ if (!pid_page)
+ break;
+ memcpy(pid_page, pid_list->pids,
+ pid_list->nr_pids * sizeof(pid_t));
+ free_pages((unsigned long)pid_list->pids, pid_list->order);
+
+ pid_list->order++;
+ pid_list->pids = pid_page;
+ }
+
+ pid_list->pids[pid_list->nr_pids++] = pid;
+ trace_parser_clear(&parser);
+ ret = 0;
+ }
+ trace_parser_put(&parser);
+
+ if (ret < 0) {
+ if (pid_list)
+ free_pages((unsigned long)pid_list->pids, pid_list->order);
+ kfree(pid_list);
+ mutex_unlock(&event_mutex);
+ return ret;
+ }
+
+ if (!pid_list) {
+ mutex_unlock(&event_mutex);
+ return ret;
+ }
+
+ sort(pid_list->pids, pid_list->nr_pids, sizeof(pid_t), cmp_pid, NULL);
+
+ /* Remove duplicates */
+ for (i = 1; i < pid_list->nr_pids; i++) {
+ int start = i;
+
+ while (i < pid_list->nr_pids &&
+ pid_list->pids[i - 1] == pid_list->pids[i])
+ i++;
+
+ if (start != i) {
+ if (i < pid_list->nr_pids) {
+ memmove(&pid_list->pids[start], &pid_list->pids[i],
+ (pid_list->nr_pids - i) * sizeof(pid_t));
+ pid_list->nr_pids -= i - start;
+ i = start;
+ } else
+ pid_list->nr_pids = start;
+ }
+ }
+
+ rcu_assign_pointer(tr->filtered_pids, pid_list);
+
+ list_for_each_entry(file, &tr->events, list) {
+ set_bit(EVENT_FILE_FL_PID_FILTER_BIT, &file->flags);
+ }
+
+ if (filtered_pids) {
+ synchronize_sched();
+
+ free_pages((unsigned long)filtered_pids->pids, filtered_pids->order);
+ kfree(filtered_pids);
+ } else {
+ /*
+ * Register a probe that is called before all other probes
+ * to set ignore_pid if next or prev do not match.
+ * Register a probe this is called after all other probes
+ * to only keep ignore_pid set if next pid matches.
+ */
+ register_trace_prio_sched_switch(event_filter_pid_sched_switch_probe_pre,
+ tr, INT_MAX);
+ register_trace_prio_sched_switch(event_filter_pid_sched_switch_probe_post,
+ tr, 0);
+
+ register_trace_prio_sched_wakeup(event_filter_pid_sched_wakeup_probe_pre,
+ tr, INT_MAX);
+ register_trace_prio_sched_wakeup(event_filter_pid_sched_wakeup_probe_post,
+ tr, 0);
+ }
+
+ /*
+ * Ignoring of pids is done at task switch. But we have to
+ * check for those tasks that are currently running.
+ * Always do this in case a pid was appended or removed.
+ */
+ on_each_cpu(ignore_task_cpu, tr, 1);
+
+ mutex_unlock(&event_mutex);
+
+ ret = read;
+ *ppos += read;
+
+ return ret;
+}
+
static int ftrace_event_avail_open(struct inode *inode, struct file *file);
static int ftrace_event_set_open(struct inode *inode, struct file *file);
+static int ftrace_event_set_pid_open(struct inode *inode, struct file *file);
static int ftrace_event_release(struct inode *inode, struct file *file);
static const struct seq_operations show_event_seq_ops = {
.stop = t_stop,
};
+static const struct seq_operations show_set_pid_seq_ops = {
+ .start = p_start,
+ .next = p_next,
+ .show = p_show,
+ .stop = p_stop,
+};
+
static const struct file_operations ftrace_avail_fops = {
.open = ftrace_event_avail_open,
.read = seq_read,
.release = ftrace_event_release,
};
+static const struct file_operations ftrace_set_event_pid_fops = {
+ .open = ftrace_event_set_pid_open,
+ .read = seq_read,
+ .write = ftrace_event_pid_write,
+ .llseek = seq_lseek,
+ .release = ftrace_event_release,
+};
+
static const struct file_operations ftrace_enable_fops = {
.open = tracing_open_generic,
.read = event_enable_read,
return ret;
}
+static int
+ftrace_event_set_pid_open(struct inode *inode, struct file *file)
+{
+ const struct seq_operations *seq_ops = &show_set_pid_seq_ops;
+ struct trace_array *tr = inode->i_private;
+ int ret;
+
+ if (trace_array_get(tr) < 0)
+ return -ENODEV;
+
+ if ((file->f_mode & FMODE_WRITE) &&
+ (file->f_flags & O_TRUNC))
+ ftrace_clear_event_pids(tr);
+
+ ret = ftrace_event_open(inode, file, seq_ops);
+ if (ret < 0)
+ trace_array_put(tr);
+ return ret;
+}
+
static struct event_subsystem *
create_new_subsystem(const char *name)
{
system->ref_count = 1;
/* Only allocate if dynamic (kprobes and modules) */
- if (!core_kernel_data((unsigned long)name)) {
- system->ref_count |= SYSTEM_FL_FREE_NAME;
- system->name = kstrdup(name, GFP_KERNEL);
- if (!system->name)
- goto out_free;
- } else
- system->name = name;
+ system->name = kstrdup_const(name, GFP_KERNEL);
+ if (!system->name)
+ goto out_free;
system->filter = NULL;
return system;
out_free:
- if (system->ref_count & SYSTEM_FL_FREE_NAME)
- kfree(system->name);
+ kfree_const(system->name);
kfree(system);
return NULL;
}
return -ENOMEM;
}
+ entry = tracefs_create_file("set_event_pid", 0644, parent,
+ tr, &ftrace_set_event_pid_fops);
+
/* ring buffer internal formats */
trace_create_file("header_page", 0444, d_events,
ring_buffer_print_page_header,
/* Disable any event triggers and associated soft-disabled events */
clear_event_triggers(tr);
+ /* Clear the pid list */
+ __ftrace_clear_event_pids(tr);
+
/* Disable any running events */
__ftrace_set_clr_event_nolock(tr, NULL, NULL, NULL, 0);
if (!token)
break;
- if (!*token)
- continue;
- /* Restarting syscalls requires that we stop them first */
- if (disable_first)
- ftrace_set_clr_event(tr, token, 0);
+ if (*token) {
+ /* Restarting syscalls requires that we stop them first */
+ if (disable_first)
+ ftrace_set_clr_event(tr, token, 0);
- ret = ftrace_set_clr_event(tr, token, 1);
- if (ret)
- pr_warn("Failed to enable trace event: %s\n", token);
+ ret = ftrace_set_clr_event(tr, token, 1);
+ if (ret)
+ pr_warn("Failed to enable trace event: %s\n", token);
+ }
/* Put back the comma to allow this to be called again */
if (buf)
static DEFINE_PER_CPU(atomic_t, ftrace_test_event_disable);
-static void
+static struct trace_array *event_tr;
+
+static void __init
function_test_events_call(unsigned long ip, unsigned long parent_ip,
struct ftrace_ops *op, struct pt_regs *pt_regs)
{
entry->ip = ip;
entry->parent_ip = parent_ip;
- trace_buffer_unlock_commit(buffer, event, flags, pc);
+ trace_buffer_unlock_commit(event_tr, buffer, event, flags, pc);
out:
atomic_dec(&per_cpu(ftrace_test_event_disable, cpu));
static __init void event_trace_self_test_with_function(void)
{
int ret;
+ event_tr = top_trace_array();
+ if (WARN_ON(!event_tr))
+ return;
ret = register_ftrace_function(&trace_ops);
if (WARN_ON(ret < 0)) {
pr_info("Failed to enable function tracer for event tests\n");
projects / karo-tx-linux.git / blobdiff