From 3a6593050fbd8bbcaed3a44d01c31d907315c86c Mon Sep 17 00:00:00 2001
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
Date: Tue, 21 Jul 2009 17:34:57 +0200
Subject: perf_counter, ftrace: Fix perf_counter integration
Adds possible second part to the assign argument of TP_EVENT().
TP_perf_assign(
__perf_count(foo);
__perf_addr(bar);
)
Which, when specified make the swcounter increment with @foo instead
of the usual 1, and report @bar for PERF_SAMPLE_ADDR (data address
associated with the event) when this triggers a counter overflow.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
include/trace/ftrace.h | 110 ++++++++++++++++++++++++++++++++++++++-----------
1 file changed, 85 insertions(+), 25 deletions(-)
(limited to 'include/trace')
diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h
index 1867553..fec71f8 100644
--- a/include/trace/ftrace.h
+++ b/include/trace/ftrace.h
@@ -144,6 +144,9 @@
#undef TP_fast_assign
#define TP_fast_assign(args...) args
+#undef TP_perf_assign
+#define TP_perf_assign(args...)
+
#undef TRACE_EVENT
#define TRACE_EVENT(call, proto, args, tstruct, func, print) \
static int \
@@ -345,6 +348,88 @@ static inline int ftrace_get_offsets_##call( \
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
+#ifdef CONFIG_EVENT_PROFILE
+
+/*
+ * Generate the functions needed for tracepoint perf_counter support.
+ *
+ * static void ftrace_profile_<call>(proto)
+ * {
+ * extern void perf_tpcounter_event(int, u64, u64);
+ * u64 __addr = 0, __count = 1;
+ *
+ * <assign> <-- here we expand the TP_perf_assign() macro
+ *
+ * perf_tpcounter_event(event_<call>.id, __addr, __count);
+ * }
+ *
+ * static int ftrace_profile_enable_<call>(struct ftrace_event_call *event_call)
+ * {
+ * int ret = 0;
+ *
+ * if (!atomic_inc_return(&event_call->profile_count))
+ * ret = register_trace_<call>(ftrace_profile_<call>);
+ *
+ * return ret;
+ * }
+ *
+ * static void ftrace_profile_disable_<call>(struct ftrace_event_call *event_call)
+ * {
+ * if (atomic_add_negative(-1, &event->call->profile_count))
+ * unregister_trace_<call>(ftrace_profile_<call>);
+ * }
+ *
+ */
+
+#undef TP_fast_assign
+#define TP_fast_assign(args...)
+
+#undef TP_perf_assign
+#define TP_perf_assign(args...) args
+
+#undef __perf_addr
+#define __perf_addr(a) __addr = (a)
+
+#undef __perf_count
+#define __perf_count(c) __count = (c)
+
+#undef TRACE_EVENT
+#define TRACE_EVENT(call, proto, args, tstruct, assign, print) \
+ \
+static void ftrace_profile_##call(proto) \
+{ \
+ extern void perf_tpcounter_event(int, u64, u64); \
+ u64 __addr = 0, __count = 1; \
+ { assign; } \
+ perf_tpcounter_event(event_##call.id, __addr, __count); \
+} \
+ \
+static int ftrace_profile_enable_##call(struct ftrace_event_call *event_call) \
+{ \
+ int ret = 0; \
+ \
+ if (!atomic_inc_return(&event_call->profile_count)) \
+ ret = register_trace_##call(ftrace_profile_##call); \
+ \
+ return ret; \
+} \
+ \
+static void ftrace_profile_disable_##call(struct ftrace_event_call *event_call)\
+{ \
+ if (atomic_add_negative(-1, &event_call->profile_count)) \
+ unregister_trace_##call(ftrace_profile_##call); \
+}
+
+#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
+
+#undef TP_fast_assign
+#define TP_fast_assign(args...) args
+
+#undef TP_perf_assign
+#define TP_perf_assign(args...)
+
+#endif
+
/*
* Stage 4 of the trace events.
*
@@ -447,28 +532,6 @@ static inline int ftrace_get_offsets_##call( \
#define TP_FMT(fmt, args...) fmt "\n", ##args
#ifdef CONFIG_EVENT_PROFILE
-#define _TRACE_PROFILE(call, proto, args) \
-static void ftrace_profile_##call(proto) \
-{ \
- extern void perf_tpcounter_event(int); \
- perf_tpcounter_event(event_##call.id); \
-} \
- \
-static int ftrace_profile_enable_##call(struct ftrace_event_call *event_call) \
-{ \
- int ret = 0; \
- \
- if (!atomic_inc_return(&event_call->profile_count)) \
- ret = register_trace_##call(ftrace_profile_##call); \
- \
- return ret; \
-} \
- \
-static void ftrace_profile_disable_##call(struct ftrace_event_call *event_call)\
-{ \
- if (atomic_add_negative(-1, &event_call->profile_count)) \
- unregister_trace_##call(ftrace_profile_##call); \
-}
#define _TRACE_PROFILE_INIT(call) \
.profile_count = ATOMIC_INIT(-1), \
@@ -476,7 +539,6 @@ static void ftrace_profile_disable_##call(struct ftrace_event_call *event_call)\
.profile_disable = ftrace_profile_disable_##call,
#else
-#define _TRACE_PROFILE(call, proto, args)
#define _TRACE_PROFILE_INIT(call)
#endif
@@ -502,7 +564,6 @@ static void ftrace_profile_disable_##call(struct ftrace_event_call *event_call)\
#undef TRACE_EVENT
#define TRACE_EVENT(call, proto, args, tstruct, assign, print) \
-_TRACE_PROFILE(call, PARAMS(proto), PARAMS(args)) \
\
static struct ftrace_event_call event_##call; \
\
@@ -586,6 +647,5 @@ __attribute__((section("_ftrace_events"))) event_##call = { \
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
-#undef _TRACE_PROFILE
#undef _TRACE_PROFILE_INIT
--
cgit v1.1
From f413cdb80ce00ec1a4d0ab949b5d96c81cae7f75 Mon Sep 17 00:00:00 2001
From: Frederic Weisbecker <fweisbec@gmail.com>
Date: Fri, 7 Aug 2009 01:25:54 +0200
Subject: perf_counter: Fix/complete ftrace event records sampling
This patch implements the kernel side support for ftrace event
record sampling.
A new counter sampling attribute is added:
PERF_SAMPLE_TP_RECORD
which requests ftrace events record sampling. In this case
if a PERF_TYPE_TRACEPOINT counter is active and a tracepoint
fires, we emit the tracepoint binary record to the
perfcounter event buffer, as a sample.
Result, after setting PERF_SAMPLE_TP_RECORD attribute from perf
record:
perf record -f -F 1 -a -e workqueue:workqueue_execution
perf report -D
0x21e18 [0x48]: event: 9
.
. ... raw event: size 72 bytes
. 0000: 09 00 00 00 01 00 48 00 d0 c7 00 81 ff ff ff ff ......H........
. 0010: 0a 00 00 00 0a 00 00 00 21 00 00 00 00 00 00 00 ........!......
. 0020: 2b 00 01 02 0a 00 00 00 0a 00 00 00 65 76 65 6e +...........eve
. 0030: 74 73 2f 31 00 00 00 00 00 00 00 00 0a 00 00 00 ts/1...........
. 0040: e0 b1 31 81 ff ff ff ff .......
.
0x21e18 [0x48]: PERF_EVENT_SAMPLE (IP, 1): 10: 0xffffffff8100c7d0 period: 33
The raw ftrace binary record starts at offset 0020.
Translation:
struct trace_entry {
type = 0x2b = 43;
flags = 1;
preempt_count = 2;
pid = 0xa = 10;
tgid = 0xa = 10;
}
thread_comm = "events/1"
thread_pid = 0xa = 10;
func = 0xffffffff8131b1e0 = flush_to_ldisc()
What will come next?
- Userspace support ('perf trace'), 'flight data recorder' mode
for perf trace, etc.
- The unconditional copy from the profiling callback brings
some costs however if someone wants no such sampling to
occur, and needs to be fixed in the future. For that we need
to have an instant access to the perf counter attribute.
This is a matter of a flag to add in the struct ftrace_event.
- Take care of the events recursivity! Don't ever try to record
a lock event for example, it seems some locking is used in
the profiling fast path and lead to a tracing recursivity.
That will be fixed using raw spinlock or recursivity
protection.
- [...]
- Profit! :-)
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Gabriel Munteanu <eduard.munteanu@linux360.ro>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
include/trace/ftrace.h | 130 ++++++++++++++++++++++++++++++++++++-------------
1 file changed, 96 insertions(+), 34 deletions(-)
(limited to 'include/trace')
diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h
index fec71f8..7fb16d9 100644
--- a/include/trace/ftrace.h
+++ b/include/trace/ftrace.h
@@ -353,15 +353,7 @@ static inline int ftrace_get_offsets_##call( \
/*
* Generate the functions needed for tracepoint perf_counter support.
*
- * static void ftrace_profile_<call>(proto)
- * {
- * extern void perf_tpcounter_event(int, u64, u64);
- * u64 __addr = 0, __count = 1;
- *
- * <assign> <-- here we expand the TP_perf_assign() macro
- *
- * perf_tpcounter_event(event_<call>.id, __addr, __count);
- * }
+ * NOTE: The insertion profile callback (ftrace_profile_<call>) is defined later
*
* static int ftrace_profile_enable_<call>(struct ftrace_event_call *event_call)
* {
@@ -381,28 +373,10 @@ static inline int ftrace_get_offsets_##call( \
*
*/
-#undef TP_fast_assign
-#define TP_fast_assign(args...)
-
-#undef TP_perf_assign
-#define TP_perf_assign(args...) args
-
-#undef __perf_addr
-#define __perf_addr(a) __addr = (a)
-
-#undef __perf_count
-#define __perf_count(c) __count = (c)
-
#undef TRACE_EVENT
#define TRACE_EVENT(call, proto, args, tstruct, assign, print) \
\
-static void ftrace_profile_##call(proto) \
-{ \
- extern void perf_tpcounter_event(int, u64, u64); \
- u64 __addr = 0, __count = 1; \
- { assign; } \
- perf_tpcounter_event(event_##call.id, __addr, __count); \
-} \
+static void ftrace_profile_##call(proto); \
\
static int ftrace_profile_enable_##call(struct ftrace_event_call *event_call) \
{ \
@@ -422,12 +396,6 @@ static void ftrace_profile_disable_##call(struct ftrace_event_call *event_call)\
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
-#undef TP_fast_assign
-#define TP_fast_assign(args...) args
-
-#undef TP_perf_assign
-#define TP_perf_assign(args...)
-
#endif
/*
@@ -647,5 +615,99 @@ __attribute__((section("_ftrace_events"))) event_##call = { \
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
+/*
+ * Define the insertion callback to profile events
+ *
+ * The job is very similar to ftrace_raw_event_<call> except that we don't
+ * insert in the ring buffer but in a perf counter.
+ *
+ * static void ftrace_profile_<call>(proto)
+ * {
+ * struct ftrace_data_offsets_<call> __maybe_unused __data_offsets;
+ * struct ftrace_event_call *event_call = &event_<call>;
+ * extern void perf_tpcounter_event(int, u64, u64, void *, int);
+ * struct ftrace_raw_##call *entry;
+ * u64 __addr = 0, __count = 1;
+ * unsigned long irq_flags;
+ * int __entry_size;
+ * int __data_size;
+ * int pc;
+ *
+ * local_save_flags(irq_flags);
+ * pc = preempt_count();
+ *
+ * __data_size = ftrace_get_offsets_<call>(&__data_offsets, args);
+ * __entry_size = __data_size + sizeof(*entry);
+ *
+ * do {
+ * char raw_data[__entry_size]; <- allocate our sample in the stack
+ * struct trace_entry *ent;
+ *
+ * entry = (struct ftrace_raw_<call> *)raw_data;
+ * ent = &entry->ent;
+ * tracing_generic_entry_update(ent, irq_flags, pc);
+ * ent->type = event_call->id;
+ *
+ * <tstruct> <- do some jobs with dynamic arrays
+ *
+ * <assign> <- affect our values
+ *
+ * perf_tpcounter_event(event_call->id, __addr, __count, entry,
+ * __entry_size); <- submit them to perf counter
+ * } while (0);
+ *
+ * }
+ */
+
+#ifdef CONFIG_EVENT_PROFILE
+
+#undef __perf_addr
+#define __perf_addr(a) __addr = (a)
+
+#undef __perf_count
+#define __perf_count(c) __count = (c)
+
+#undef TRACE_EVENT
+#define TRACE_EVENT(call, proto, args, tstruct, assign, print) \
+static void ftrace_profile_##call(proto) \
+{ \
+ struct ftrace_data_offsets_##call __maybe_unused __data_offsets;\
+ struct ftrace_event_call *event_call = &event_##call; \
+ extern void perf_tpcounter_event(int, u64, u64, void *, int); \
+ struct ftrace_raw_##call *entry; \
+ u64 __addr = 0, __count = 1; \
+ unsigned long irq_flags; \
+ int __entry_size; \
+ int __data_size; \
+ int pc; \
+ \
+ local_save_flags(irq_flags); \
+ pc = preempt_count(); \
+ \
+ __data_size = ftrace_get_offsets_##call(&__data_offsets, args); \
+ __entry_size = ALIGN(__data_size + sizeof(*entry), sizeof(u64));\
+ \
+ do { \
+ char raw_data[__entry_size]; \
+ struct trace_entry *ent; \
+ \
+ entry = (struct ftrace_raw_##call *)raw_data; \
+ ent = &entry->ent; \
+ tracing_generic_entry_update(ent, irq_flags, pc); \
+ ent->type = event_call->id; \
+ \
+ tstruct \
+ \
+ { assign; } \
+ \
+ perf_tpcounter_event(event_call->id, __addr, __count, entry,\
+ __entry_size); \
+ } while (0); \
+ \
+}
+
+#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
+#endif /* CONFIG_EVENT_PROFILE */
+
#undef _TRACE_PROFILE_INIT
--
cgit v1.1
From a044560c3a1f0ad75ce685c1ed7604820b9ed319 Mon Sep 17 00:00:00 2001
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
Date: Mon, 10 Aug 2009 11:16:52 +0200
Subject: perf_counter: Correct PERF_SAMPLE_RAW output
PERF_SAMPLE_* output switches should unconditionally output the
correct format, as they are the only way to unambiguously parse
the PERF_EVENT_SAMPLE data.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1249896447.17467.74.camel@twins>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
include/trace/ftrace.h | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
(limited to 'include/trace')
diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h
index 7fb16d9..7167b9b 100644
--- a/include/trace/ftrace.h
+++ b/include/trace/ftrace.h
@@ -685,7 +685,8 @@ static void ftrace_profile_##call(proto) \
pc = preempt_count(); \
\
__data_size = ftrace_get_offsets_##call(&__data_offsets, args); \
- __entry_size = ALIGN(__data_size + sizeof(*entry), sizeof(u64));\
+ __entry_size = ALIGN(__data_size + sizeof(*entry) + sizeof(u32),\
+ sizeof(u64)); \
\
do { \
char raw_data[__entry_size]; \
--
cgit v1.1
From 304703aba31a87903b8c0db8f5e6890cac2d596d Mon Sep 17 00:00:00 2001
From: Frederic Weisbecker <fweisbec@gmail.com>
Date: Mon, 10 Aug 2009 16:11:32 +0200
Subject: perf_counter: Subtract the buffer size field from the event record
size
We compute the perf raw sample size by aligning the raw ftrace
event size plus the buffer size field itself. We do that
instead of aligning only the perf raw sample size, so that we
might economize some in some cases.
But this buffer size field is not stored in the perf raw
sample, we must then substract its size from the buffer once we
computed the alignment unless we may get a useless u32 field in
the buffer.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <20090810141129.GA5124@nowhere>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
include/trace/ftrace.h | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
(limited to 'include/trace')
diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h
index 7167b9b..a05524f 100644
--- a/include/trace/ftrace.h
+++ b/include/trace/ftrace.h
@@ -637,7 +637,12 @@ __attribute__((section("_ftrace_events"))) event_##call = { \
* pc = preempt_count();
*
* __data_size = ftrace_get_offsets_<call>(&__data_offsets, args);
- * __entry_size = __data_size + sizeof(*entry);
+ *
+ * // Below we want to get the aligned size by taking into account
+ * // the u32 field that will later store the buffer size
+ * __entry_size = ALIGN(__data_size + sizeof(*entry) + sizeof(u32),
+ * sizeof(u64));
+ * __entry_size -= sizeof(u32);
*
* do {
* char raw_data[__entry_size]; <- allocate our sample in the stack
@@ -687,6 +692,7 @@ static void ftrace_profile_##call(proto) \
__data_size = ftrace_get_offsets_##call(&__data_offsets, args); \
__entry_size = ALIGN(__data_size + sizeof(*entry) + sizeof(u32),\
sizeof(u64)); \
+ __entry_size -= sizeof(u32); \
\
do { \
char raw_data[__entry_size]; \
--
cgit v1.1
From 1853db0e02ae4088f102b0d8e59e83dc98f93f03 Mon Sep 17 00:00:00 2001
From: Frederic Weisbecker <fweisbec@gmail.com>
Date: Mon, 10 Aug 2009 16:38:36 +0200
Subject: perf_counter: Zero dead bytes from ftrace raw samples size alignment
After aligning the ftrace raw samples, there are dead bytes storing
random data from the stack. We don't want to leak these to userspace,
then zero these out.
Before:
0x2de88 [0x50]: event: 9
.
. ... raw event: size 80 bytes
. 0000: 09 00 00 00 01 00 50 00 d0 c7 00 81 ff ff ff ff ......P........
. 0010: 68 01 00 00 68 01 00 00 2c 00 00 00 00 00 00 00 h...h...,......
. 0020: 2c 00 00 00 2b 00 01 02 68 01 00 00 68 01 00 00 ,...+...h...h..
. 0030: 6b 6f 6e 64 65 6d 61 6e 64 2f 30 00 00 00 00 00 kondemand/0....
. 0040: 68 01 00 00 40 7f 46 81 ff ff ff ff 00 10 1b 7f h...@.F........
^ ^ ^ ^
Leak
After:
0x2d318 [0x50]: event: 9
.
. ... raw event: size 80 bytes
. 0000: 09 00 00 00 01 00 50 00 d0 c7 00 81 ff ff ff ff ......P........
. 0010: 68 01 00 00 68 01 00 00 68 14 00 00 00 00 00 00 h...h...h......
. 0020: 2c 00 00 00 2b 00 01 02 68 01 00 00 68 01 00 00 ,...+...h...h..
. 0030: 6b 6f 6e 64 65 6d 61 6e 64 2f 30 00 00 00 00 00 kondemand/0....
. 0040: 68 01 00 00 a0 80 46 81 ff ff ff ff 00 00 00 00 h.....F........
^ ^ ^ ^
Fixed
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1249915116-5210-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
---
include/trace/ftrace.h | 4 ++++
1 file changed, 4 insertions(+)
(limited to 'include/trace')
diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h
index a05524f..f64fbaa 100644
--- a/include/trace/ftrace.h
+++ b/include/trace/ftrace.h
@@ -648,6 +648,9 @@ __attribute__((section("_ftrace_events"))) event_##call = { \
* char raw_data[__entry_size]; <- allocate our sample in the stack
* struct trace_entry *ent;
*
+ * zero dead bytes from alignment to avoid stack leak to userspace:
+ *
+ * *(u64 *)(&raw_data[__entry_size - sizeof(u64)]) = 0ULL;
* entry = (struct ftrace_raw_<call> *)raw_data;
* ent = &entry->ent;
* tracing_generic_entry_update(ent, irq_flags, pc);
@@ -698,6 +701,7 @@ static void ftrace_profile_##call(proto) \
char raw_data[__entry_size]; \
struct trace_entry *ent; \
\
+ *(u64 *)(&raw_data[__entry_size - sizeof(u64)]) = 0ULL; \
entry = (struct ftrace_raw_##call *)raw_data; \
ent = &entry->ent; \
tracing_generic_entry_update(ent, irq_flags, pc); \
--
cgit v1.1