* [PATCH 1/3] ftrace: Check sample types only for sampling events
2015-11-26 19:34 [PATCHv2 0/3] perf ftrace: Several perf ftrace:function event fixes Jiri Olsa
@ 2015-11-26 19:34 ` Jiri Olsa
2015-11-26 19:34 ` [PATCH 2/3] perf: Move exclude_kernel tracepoint check to init event Jiri Olsa
2015-11-26 19:34 ` [PATCH 3/3] perf ftrace: Use ftrace_ops::private to store event pointer Jiri Olsa
2 siblings, 0 replies; 7+ messages in thread
From: Jiri Olsa @ 2015-11-26 19:34 UTC (permalink / raw)
To: Steven Rostedt
Cc: lkml, David Ahern, Ingo Molnar, Namhyung Kim, Peter Zijlstra,
Arnaldo Carvalho de Melo
Currently we check sample type for ftrace:function event
even if it's not created as sampling event. That prevents
creating ftrace_function event in counting mode.
Making sure we check sample types only for sampling events.
Before:
$ sudo perf stat -e ftrace:function ls
...
Performance counter stats for 'ls':
<not supported> ftrace:function
0.001983662 seconds time elapsed
After:
$ sudo perf stat -e ftrace:function ls
...
Performance counter stats for 'ls':
44,498 ftrace:function
0.037534722 seconds time elapsed
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
kernel/trace/trace_event_perf.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c
index cc9f7a9319be..c41463af3298 100644
--- a/kernel/trace/trace_event_perf.c
+++ b/kernel/trace/trace_event_perf.c
@@ -52,14 +52,14 @@ static int perf_trace_event_perm(struct trace_event_call *tp_event,
* event, due to issues with page faults while tracing page
* fault handler and its overall trickiness nature.
*/
- if (!p_event->attr.exclude_callchain_user)
+ if (is_sampling_event(p_event) && !p_event->attr.exclude_callchain_user)
return -EINVAL;
/*
* Same reason to disable user stack dump as for user space
* callchains above.
*/
- if (p_event->attr.sample_type & PERF_SAMPLE_STACK_USER)
+ if (is_sampling_event(p_event) && p_event->attr.sample_type & PERF_SAMPLE_STACK_USER)
return -EINVAL;
}
--
2.4.3
^ permalink raw reply related [flat|nested] 7+ messages in thread* [PATCH 2/3] perf: Move exclude_kernel tracepoint check to init event
2015-11-26 19:34 [PATCHv2 0/3] perf ftrace: Several perf ftrace:function event fixes Jiri Olsa
2015-11-26 19:34 ` [PATCH 1/3] ftrace: Check sample types only for sampling events Jiri Olsa
@ 2015-11-26 19:34 ` Jiri Olsa
2015-11-26 19:41 ` Arnaldo Carvalho de Melo
2015-11-26 19:34 ` [PATCH 3/3] perf ftrace: Use ftrace_ops::private to store event pointer Jiri Olsa
2 siblings, 1 reply; 7+ messages in thread
From: Jiri Olsa @ 2015-11-26 19:34 UTC (permalink / raw)
To: Steven Rostedt
Cc: lkml, David Ahern, Ingo Molnar, Namhyung Kim, Peter Zijlstra,
Arnaldo Carvalho de Melo
We suppress events with attr::exclude_kernel set when
the event is generated, so following capture will
give no warning and produce no data:
$ sudo perf record -e sched:sched_switch:u ls
$ sudo /perf script | wc -l
0
Checking the attr::exclude_kernel at the event init
time and failing right away:
$ sudo perf record -e sched:sched_switch:u ls
Error:
The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (sched:sched_switch).
/bin/dmesg may provide additional information.
No CONFIG_PERF_EVENTS=y kernel support configured?
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
kernel/events/core.c | 5 -----
kernel/trace/trace_event_perf.c | 15 +++++++++++++++
2 files changed, 15 insertions(+), 5 deletions(-)
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 5854fcf7f05a..9fb9d5ef6825 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -6938,11 +6938,6 @@ static int perf_tp_event_match(struct perf_event *event,
{
if (event->hw.state & PERF_HES_STOPPED)
return 0;
- /*
- * All tracepoints are from kernel-space.
- */
- if (event->attr.exclude_kernel)
- return 0;
if (!perf_tp_filter_match(event, data))
return 0;
diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c
index c41463af3298..637268855296 100644
--- a/kernel/trace/trace_event_perf.c
+++ b/kernel/trace/trace_event_perf.c
@@ -182,11 +182,26 @@ static void perf_trace_event_close(struct perf_event *p_event)
tp_event->class->reg(tp_event, TRACE_REG_PERF_CLOSE, p_event);
}
+static int perf_trace_event_attr(struct perf_event *event)
+{
+ /*
+ * All tracepoints are from kernel-space.
+ */
+ if (event->attr.exclude_kernel)
+ return -EINVAL;
+
+ return 0;
+}
+
static int perf_trace_event_init(struct trace_event_call *tp_event,
struct perf_event *p_event)
{
int ret;
+ ret = perf_trace_event_attr(p_event);
+ if (ret)
+ return ret;
+
ret = perf_trace_event_perm(tp_event, p_event);
if (ret)
return ret;
--
2.4.3
^ permalink raw reply related [flat|nested] 7+ messages in thread* [PATCH 3/3] perf ftrace: Use ftrace_ops::private to store event pointer
2015-11-26 19:34 [PATCHv2 0/3] perf ftrace: Several perf ftrace:function event fixes Jiri Olsa
2015-11-26 19:34 ` [PATCH 1/3] ftrace: Check sample types only for sampling events Jiri Olsa
2015-11-26 19:34 ` [PATCH 2/3] perf: Move exclude_kernel tracepoint check to init event Jiri Olsa
@ 2015-11-26 19:34 ` Jiri Olsa
2 siblings, 0 replies; 7+ messages in thread
From: Jiri Olsa @ 2015-11-26 19:34 UTC (permalink / raw)
To: Steven Rostedt
Cc: lkml, David Ahern, Ingo Molnar, Namhyung Kim, Peter Zijlstra,
Arnaldo Carvalho de Melo
Having following commands running concurently:
# perf record -e ftrace:function -a -o krava.data sleep 10
# perf record -e ftrace:function --filter 'ip == SyS_read' ls
will endup in the latter one failing on the filter
rules and store all functions (in perf.data) as
instructed by the first record instead of just
SyS_read records.
The reason is that we don't check the ftrace_ops that
triggered the event with event's ftrace_ops. Hence
once running together the event from latter perf will
get all the data of the event from the first one.
Fixing this by using ftrace_ops::private value to keep
the perf_event pointer. This way we don't need to search
for triggered event (as tracepoint handler does) and
directly store sample.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
include/linux/perf_event.h | 3 +++
kernel/events/core.c | 25 +++++++++++++++++++++++++
kernel/trace/trace_event_perf.c | 9 ++-------
3 files changed, 30 insertions(+), 7 deletions(-)
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index f9828a48f16a..e438f909df31 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -1009,6 +1009,9 @@ extern void perf_tp_event(u64 addr, u64 count, void *record,
int entry_size, struct pt_regs *regs,
struct hlist_head *head, int rctx,
struct task_struct *task);
+void perf_function_event(struct perf_event *event,
+ void *record, int entry_size,
+ struct pt_regs *regs, int rctx);
extern void perf_bp_event(struct perf_event *event, void *data);
#ifndef perf_misc_flags
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 9fb9d5ef6825..dc98f12c55e2 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -7103,6 +7103,31 @@ static void perf_event_free_bpf_prog(struct perf_event *event)
}
}
+#ifdef CONFIG_FUNCTION_TRACER
+void perf_function_event(struct perf_event *event,
+ void *record, int entry_size,
+ struct pt_regs *regs, int rctx)
+
+{
+ struct perf_sample_data data;
+ struct perf_raw_record raw = {
+ .size = entry_size,
+ .data = record,
+ };
+
+ if (event->hw.state & PERF_HES_STOPPED)
+ goto out;
+
+ perf_sample_data_init(&data, 0, 0);
+ data.raw = &raw;
+
+ perf_swevent_event(event, 1, &data, regs);
+
+out:
+ perf_swevent_put_recursion_context(rctx);
+}
+#endif /* CONFIG_FUNCTION_TRACER */
+
#else
static inline void perf_tp_register(void)
diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c
index 637268855296..396a39988bde 100644
--- a/kernel/trace/trace_event_perf.c
+++ b/kernel/trace/trace_event_perf.c
@@ -318,14 +318,9 @@ perf_ftrace_function_call(unsigned long ip, unsigned long parent_ip,
struct ftrace_ops *ops, struct pt_regs *pt_regs)
{
struct ftrace_entry *entry;
- struct hlist_head *head;
struct pt_regs regs;
int rctx;
- head = this_cpu_ptr(event_function.perf_events);
- if (hlist_empty(head))
- return;
-
#define ENTRY_SIZE (ALIGN(sizeof(struct ftrace_entry) + sizeof(u32), \
sizeof(u64)) - sizeof(u32))
@@ -339,8 +334,7 @@ perf_ftrace_function_call(unsigned long ip, unsigned long parent_ip,
entry->ip = ip;
entry->parent_ip = parent_ip;
- perf_trace_buf_submit(entry, ENTRY_SIZE, rctx, 0,
- 1, ®s, head, NULL);
+ perf_function_event(ops->private, entry, ENTRY_SIZE, ®s, rctx);
#undef ENTRY_SIZE
}
@@ -349,6 +343,7 @@ static int perf_ftrace_function_register(struct perf_event *event)
{
struct ftrace_ops *ops = &event->ftrace_ops;
+ ops->private = event;
ops->flags |= FTRACE_OPS_FL_CONTROL;
ops->func = perf_ftrace_function_call;
return register_ftrace_function(ops);
--
2.4.3
^ permalink raw reply related [flat|nested] 7+ messages in thread