#include <linux/slab.h>
#include <linux/delay.h>
+#include <trace/events/sched.h>
+
#include <asm/setup.h>
#include "trace_output.h"
}
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;
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 */
}
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;
}
static void p_stop(struct seq_file *m, void *p)
+ __releases(RCU)
{
rcu_read_unlock_sched();
mutex_unlock(&event_mutex);
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 *file, const char __user *ubuf,
+ftrace_event_pid_write(struct file *filp, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
- struct seq_file *m = file->private_data;
+ 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;
rcu_assign_pointer(tr->filtered_pids, pid_list);
- mutex_unlock(&event_mutex);
+ 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;
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)
projects / linux-2.6-microblaze.git / blobdiff