tracing/profile: Add filter support
- Add an ioctl to allocate a filter for a perf event.
- Free the filter when the associated perf event is to be freed.
- Do the filtering in perf_swevent_match().
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <4AD69546.8050401@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 9d0b5c6..12b5ec3 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -28,6 +28,7 @@
#include <linux/anon_inodes.h>
#include <linux/kernel_stat.h>
#include <linux/perf_event.h>
+#include <linux/ftrace_event.h>
#include <asm/irq_regs.h>
@@ -1658,6 +1659,8 @@
return ERR_PTR(err);
}
+static void perf_event_free_filter(struct perf_event *event);
+
static void free_event_rcu(struct rcu_head *head)
{
struct perf_event *event;
@@ -1665,6 +1668,7 @@
event = container_of(head, struct perf_event, rcu_head);
if (event->ns)
put_pid_ns(event->ns);
+ perf_event_free_filter(event);
kfree(event);
}
@@ -1974,7 +1978,8 @@
return ret;
}
-int perf_event_set_output(struct perf_event *event, int output_fd);
+static int perf_event_set_output(struct perf_event *event, int output_fd);
+static int perf_event_set_filter(struct perf_event *event, void __user *arg);
static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
@@ -2002,6 +2007,9 @@
case PERF_EVENT_IOC_SET_OUTPUT:
return perf_event_set_output(event, arg);
+ case PERF_EVENT_IOC_SET_FILTER:
+ return perf_event_set_filter(event, (void __user *)arg);
+
default:
return -ENOTTY;
}
@@ -3806,9 +3814,14 @@
return 1;
}
+static int perf_tp_event_match(struct perf_event *event,
+ struct perf_sample_data *data);
+
static int perf_swevent_match(struct perf_event *event,
enum perf_type_id type,
- u32 event_id, struct pt_regs *regs)
+ u32 event_id,
+ struct perf_sample_data *data,
+ struct pt_regs *regs)
{
if (!perf_swevent_is_counting(event))
return 0;
@@ -3826,6 +3839,10 @@
return 0;
}
+ if (event->attr.type == PERF_TYPE_TRACEPOINT &&
+ !perf_tp_event_match(event, data))
+ return 0;
+
return 1;
}
@@ -3842,7 +3859,7 @@
rcu_read_lock();
list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
- if (perf_swevent_match(event, type, event_id, regs))
+ if (perf_swevent_match(event, type, event_id, data, regs))
perf_swevent_add(event, nr, nmi, data, regs);
}
rcu_read_unlock();
@@ -4086,6 +4103,7 @@
};
#ifdef CONFIG_EVENT_PROFILE
+
void perf_tp_event(int event_id, u64 addr, u64 count, void *record,
int entry_size)
{
@@ -4109,8 +4127,15 @@
}
EXPORT_SYMBOL_GPL(perf_tp_event);
-extern int ftrace_profile_enable(int);
-extern void ftrace_profile_disable(int);
+static int perf_tp_event_match(struct perf_event *event,
+ struct perf_sample_data *data)
+{
+ void *record = data->raw->data;
+
+ if (likely(!event->filter) || filter_match_preds(event->filter, record))
+ return 1;
+ return 0;
+}
static void tp_perf_event_destroy(struct perf_event *event)
{
@@ -4135,12 +4160,53 @@
return &perf_ops_generic;
}
+
+static int perf_event_set_filter(struct perf_event *event, void __user *arg)
+{
+ char *filter_str;
+ int ret;
+
+ if (event->attr.type != PERF_TYPE_TRACEPOINT)
+ return -EINVAL;
+
+ filter_str = strndup_user(arg, PAGE_SIZE);
+ if (IS_ERR(filter_str))
+ return PTR_ERR(filter_str);
+
+ ret = ftrace_profile_set_filter(event, event->attr.config, filter_str);
+
+ kfree(filter_str);
+ return ret;
+}
+
+static void perf_event_free_filter(struct perf_event *event)
+{
+ ftrace_profile_free_filter(event);
+}
+
#else
+
+static int perf_tp_event_match(struct perf_event *event,
+ struct perf_sample_data *data)
+{
+ return 1;
+}
+
static const struct pmu *tp_perf_event_init(struct perf_event *event)
{
return NULL;
}
-#endif
+
+static int perf_event_set_filter(struct perf_event *event, void __user *arg)
+{
+ return -ENOENT;
+}
+
+static void perf_event_free_filter(struct perf_event *event)
+{
+}
+
+#endif /* CONFIG_EVENT_PROFILE */
atomic_t perf_swevent_enabled[PERF_COUNT_SW_MAX];
@@ -4394,7 +4460,7 @@
goto out;
}
-int perf_event_set_output(struct perf_event *event, int output_fd)
+static int perf_event_set_output(struct perf_event *event, int output_fd)
{
struct perf_event *output_event = NULL;
struct file *output_file = NULL;