Commit graph

238 commits

Author SHA1 Message Date
Steven Rostedt
c521efd170 tracing: Add pipe_close interface
An ftrace plugin can add a pipe_open interface when the user opens
trace_pipe. But if the plugin allocates something within the pipe_open
it can not free it because there exists no pipe_close. The hook to
the trace file open has a corresponding close. The closing of the
trace_pipe file should also have a corresponding close.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-12-07 12:01:35 -05:00
Tom Zanussi
99df5a6a21 trace/syscalls: Change ret param in struct syscall_trace_exit to long
Commit ee949a86b3 ("tracing/syscalls:
Use long for syscall ret format and field definitions") changed the
syscall exit return type to long, but forgot to change it in the
struct.

Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1259133299-23594-3-git-send-email-tzanussi@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-25 09:06:10 +01:00
Ingo Molnar
96200591a3 Merge branch 'tracing/hw-breakpoints' into perf/core
Conflicts:
	arch/x86/kernel/kprobes.c
	kernel/trace/Makefile

Merge reason: hw-breakpoints perf integration is looking
              good in testing and in reviews, plus conflicts
              are mounting up - so merge & resolve.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-21 14:07:23 +01:00
Li Zefan
30ff21e31f ksym_tracer: Remove KSYM_SELFTEST_ENTRY
The macro used to be used in both trace_selftest.c and
trace_ksym.c, but no longer, so remove it from header file.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Prasad <prasad@linux.vnet.ibm.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-11-08 16:21:01 +01:00
Frederic Weisbecker
24f1e32c60 hw-breakpoints: Rewrite the hw-breakpoints layer on top of perf events
This patch rebase the implementation of the breakpoints API on top of
perf events instances.

Each breakpoints are now perf events that handle the
register scheduling, thread/cpu attachment, etc..

The new layering is now made as follows:

       ptrace       kgdb      ftrace   perf syscall
          \          |          /         /
           \         |         /         /
                                        /
            Core breakpoint API        /
                                      /
                     |               /
                     |              /

              Breakpoints perf events

                     |
                     |

               Breakpoints PMU ---- Debug Register constraints handling
                                    (Part of core breakpoint API)
                     |
                     |

             Hardware debug registers

Reasons of this rewrite:

- Use the centralized/optimized pmu registers scheduling,
  implying an easier arch integration
- More powerful register handling: perf attributes (pinned/flexible
  events, exclusive/non-exclusive, tunable period, etc...)

Impact:

- New perf ABI: the hardware breakpoints counters
- Ptrace breakpoints setting remains tricky and still needs some per
  thread breakpoints references.

Todo (in the order):

- Support breakpoints perf counter events for perf tools (ie: implement
  perf_bpcounter_event())
- Support from perf tools

Changes in v2:

- Follow the perf "event " rename
- The ptrace regression have been fixed (ptrace breakpoint perf events
  weren't released when a task ended)
- Drop the struct hw_breakpoint and store generic fields in
  perf_event_attr.
- Separate core and arch specific headers, drop
  asm-generic/hw_breakpoint.h and create linux/hw_breakpoint.h
- Use new generic len/type for breakpoint
- Handle off case: when breakpoints api is not supported by an arch

Changes in v3:

- Fix broken CONFIG_KVM, we need to propagate the breakpoint api
  changes to kvm when we exit the guest and restore the bp registers
  to the host.

Changes in v4:

- Drop the hw_breakpoint_restore() stub as it is only used by KVM
- EXPORT_SYMBOL_GPL hw_breakpoint_restore() as KVM can be built as a
  module
- Restore the breakpoints unconditionally on kvm guest exit:
  TIF_DEBUG_THREAD doesn't anymore cover every cases of running
  breakpoints and vcpu->arch.switch_db_regs might not always be
  set when the guest used debug registers.
  (Waiting for a reliable optimization)

Changes in v5:

- Split-up the asm-generic/hw-breakpoint.h moving to
  linux/hw_breakpoint.h into a separate patch
- Optimize the breakpoints restoring while switching from kvm guest
  to host. We only want to restore the state if we have active
  breakpoints to the host, otherwise we don't care about messed-up
  address registers.
- Add asm/hw_breakpoint.h to Kbuild
- Fix bad breakpoint type in trace_selftest.c

Changes in v6:

- Fix wrong header inclusion in trace.h (triggered a build
  error with CONFIG_FTRACE_SELFTEST

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Prasad <prasad@linux.vnet.ibm.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jan Kiszka <jan.kiszka@web.de>
Cc: Jiri Slaby <jirislaby@gmail.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Paul Mundt <lethal@linux-sh.org>
2009-11-08 15:34:42 +01:00
Ingo Molnar
4331595650 Merge branch 'perf/core' into perf/probes
Conflicts:
	tools/perf/Makefile

Merge reason:

 - fix the conflict
 - pick up the pr_*() infrastructure to queue up dependent patch

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-23 08:23:20 +02:00
Frederic Weisbecker
0f8f86c7bd Merge commit 'perf/core' into perf/hw-breakpoint
Conflicts:
	kernel/Makefile
	kernel/trace/Makefile
	kernel/trace/trace.h
	samples/Makefile

Merge reason: We need to be uptodate with the perf events development
branch because we plan to rewrite the breakpoints API on top of
perf events.
2009-10-18 01:12:33 +02:00
Li Zefan
6fb2915df7 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>
2009-10-15 11:35:23 +02:00
Li Zefan
b0f1a59a98 tracing/filters: Use a different op for glob match
"==" will always do a full match, and "~" will do a glob match.

In the future, we may add "=~" for regex 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: <4AD69528.3050309@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-15 11:35:22 +02:00
Li Zefan
fce29d15b5 tracing/filters: Refactor subsystem filter code
Change:
	for_each_pred
		for_each_subsystem
To:
	for_each_subsystem
		for_each_pred

This change also prepares for later patches.

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: <4AD69502.8060903@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-15 11:35:22 +02:00
jolsa@redhat.com
756d17ee7e tracing: Support multiple pids in set_pid_ftrace file
Adding the possibility to set more than 1 pid in the set_pid_ftrace
file, thus allowing to trace more than 1 independent processes.

Usage:

 sh-4.0# echo 284 > ./set_ftrace_pid
 sh-4.0# cat ./set_ftrace_pid
 284
 sh-4.0# echo 1 >> ./set_ftrace_pid
 sh-4.0# echo 0 >> ./set_ftrace_pid
 sh-4.0# cat ./set_ftrace_pid
 swapper tasks
 1
 284
 sh-4.0# echo 4 > ./set_ftrace_pid
 sh-4.0# cat ./set_ftrace_pid
 4
 sh-4.0# echo > ./set_ftrace_pid
 sh-4.0# cat ./set_ftrace_pid
 no pid
 sh-4.0#

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20091013203425.565454612@goodmis.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-14 08:13:53 +02:00
Frederic Weisbecker
bf7c5b43a1 tracing: Remove unused ftrace_trace_addr helper
Remove the ftrace_trace_addr() function as only its off-case is
implemented and there are no users of it currently.

But we keep ftrace_graph_addr() off-case, in case someone come to use
the function graph tracer to profit from top-level callers filtering.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
2009-10-13 09:33:40 +02:00
Ingo Molnar
0aa73ba1c4 Merge branch 'tracing/urgent' into tracing/core
Merge reason: Pick up latest fixes and update to latest upstream.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-10-01 11:20:48 +02:00
Frederic Weisbecker
3f6fe06dbf tracing/filters: Unify the regex parsing helpers
The filter code has stolen the regex parsing function from ftrace to
get the regex support.
We have duplicated this code, so factorize it in the filter area and
make it generally available, as the filter code is the most suited to
host this feature.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
2009-09-24 21:40:13 +02:00
Frederic Weisbecker
1889d20922 tracing/filters: Provide basic regex support
This patch provides basic support for regular expressions in filters.

It supports the following types of regexp:

- *match_beginning
- *match_middle*
- match_end*
- !don't match

Example:
	cd /debug/tracing/events/bkl/lock_kernel
	echo 'file == "*reiserfs*"' > filter
	echo 1 > enable

           gedit-4941  [000]   457.735437: lock_kernel: depth: 0, fs/reiserfs/namei.c:334 reiserfs_lookup()
     sync_supers-227   [001]   461.379985: lock_kernel: depth: 0, fs/reiserfs/super.c:69 reiserfs_sync_fs()
     sync_supers-227   [000]   461.383096: lock_kernel: depth: 0, fs/reiserfs/journal.c:1069 flush_commit_list()
      reiserfs/1-1369  [001]   461.479885: lock_kernel: depth: 0, fs/reiserfs/journal.c:3509 flush_async_commits()

Every string is now handled as a regexp in the filter framework, which
helps to factorize the code for handling both simple strings and
regexp comparisons.

(The regexp parsing code has been wildly cherry picked from ftrace.c
written by Steve.)

v2: Simplify the whole and drop the filter_regex file

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
2009-09-24 21:39:27 +02:00
Frederic Weisbecker
d7a4b414ee Merge commit 'linus/master' into tracing/kprobes
Conflicts:
	kernel/trace/Makefile
	kernel/trace/trace.h
	kernel/trace/trace_event_types.h
	kernel/trace/trace_export.c

Merge reason:
	Sync with latest significant tracing core changes.
2009-09-23 23:08:43 +02:00
Arjan van de Ven
6161352142 tracing, perf: Convert the power tracer into an event tracer
This patch converts the existing power tracer into an event tracer,
so that power events (C states and frequency changes) can be
tracked via "perf".

This also removes the perl script that was used to demo the tracer;
its functionality is being replaced entirely with timechart.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20090912130542.6d314860@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-19 11:42:12 +02:00
Steven Rostedt
4e5292ea1a tracing: use the new trace_entries.h to create format files
This patch changes the way the format files in

  debugfs/tracing/events/ftrace/*/format

are created. It uses the new trace_entries.h file to automate the
creation of the format files to ensure that they are always in sync
with the actual structures. This is the same methodology used to
create the format files for the TRACE_EVENT macro.

This also updates the filter creation that was built on the creation
of the format files.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-12 23:08:10 -04:00
Steven Rostedt
d73150943c tracing: show details of structures within the ftrace structures
Some of the internal ftrace structures use structures within. The
output of a field saying it is just a structure is useless for a format
file. A binary reader of the ring buffer needs to know more about
how the fields are broken up.

This patch adds to the ftrace structure macros new fields to
describe the structures inside a structure.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-12 23:08:07 -04:00
Steven Rostedt
0a1c49db8d tracing: use macros to create internal ftrace entry ring buffer structures
The entries used by ftrace internal code (plugins) currently have their
formats manually exported to userspace. That is, the format files in
debugfs/tracing/events/ftrace/*/format are currently created by hand.
This is a maintenance nightmare, and can easily become out of sync
with what is actually shown.

This patch uses the methodology of the TRACE_EVENT macros to build
the structures so that their formats can be automated and this
will keep the structures in sync with what users can see.

This patch only changes the way the structures are created. Further
patches will build off of this to automate the format files.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-12 23:08:06 -04:00
Carsten Emde
b5130b1e7d tracing: do not update tracing_max_latency when tracer is stopped
The state of the function pair tracing_stop()/tracing_start() is
correctly considered when tracer data are updated. However, the global
and externally accessible variable tracing_max_latency is always updated
- even when tracing is stopped.

The update should only occur, if tracing was not stopped.

Signed-off-by: Carsten Emde <C.Emde@osadl.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-12 21:45:17 -04:00
jolsa@redhat.com
b63f39ea50 tracing: create generic trace parser
Create a "trace_parser" that can parse the user space input for
separate words.

struct trace_parser is the descriptor.

Generic "trace_get_user" function that can be a helper to read multiple
words passed in by user space.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
LKML-Reference: <1252682969-3366-2-git-send-email-jolsa@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-11 14:46:55 -04:00
Steven Rostedt
48659d3119 tracing: move tgid out of generic entry and into userstack
The userstack trace required the recording of the tgid entry.
Unfortunately, it was added to the generic entry where it wasted
4 bytes of every entry and was only used by one entry.

This patch moves it out of the generic field and moves it into the
only user (userstack_entry).

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-11 11:36:23 -04:00
Frederic Weisbecker
8f8ffe2485 Merge commit 'tracing/core' into tracing/kprobes
Conflicts:
	kernel/trace/trace_export.c
	kernel/trace/trace_kprobe.c

Merge reason: This topic branch lacks an important
build fix in tracing/core:

	0dd7b74787:
	tracing: Fix double CPP substitution in TRACE_EVENT_FN

that prevents from multiple tracepoint headers inclusion crashes.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-09-11 01:09:23 +02:00
Li Zefan
197e2eabc9 tracing: move PRED macros to trace_events_filter.c
Move DEFINE_COMPARISON_PRED() and DEFINE_EQUALITY_PRED()
  to kernel/trace/trace_events_filter.c

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4AA8579B.4020706@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-09 23:54:11 -04:00
Li Zefan
a5921c6c37 tracing: remove stats from struct tracer
Remove unused field @stats from struct tracer.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4AA8579B.4020706@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-09 23:54:09 -04:00
Li Zefan
bd9cfca9cb tracing: format clean ups
Fix white-space formatting.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4AA8579B.4020706@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-09 23:54:07 -04:00
Li Zefan
e0ab5f2dae tracing: remove dead code
Removes unreachable code.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4AA8579B.4020706@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-09 23:54:06 -04:00
Ingo Molnar
a1922ed661 Merge branch 'tracing/core' into tracing/hw-breakpoints
Conflicts:
	arch/Kconfig
	kernel/trace/trace.h

Merge reason: resolve the conflicts, plus adopt to the new
              ring-buffer APIs.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-07 08:19:51 +02:00
Steven Rostedt
659372d3e4 tracing: add trace_array_printk for internal tracers to use
This patch adds a trace_array_printk to allow a tracer to use the
trace_printk on its own trace array.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-04 19:13:53 -04:00
Steven Rostedt
e77405ad80 tracing: pass around ring buffer instead of tracer
The latency tracers (irqsoff and wakeup) can swap trace buffers
on the fly. If an event is happening and has reserved data on one of
the buffers, and the latency tracer swaps the global buffer with the
max buffer, the result is that the event may commit the data to the
wrong buffer.

This patch changes the API to the trace recording to be recieve the
buffer that was used to reserve a commit. Then this buffer can be passed
in to the commit.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-04 18:59:39 -04:00
Steven Rostedt
2f26ebd549 tracing: use timestamp to determine start of latency traces
Currently the latency tracers reset the ring buffer. Unfortunately
if a commit is in process (due to a trace event), this can corrupt
the ring buffer. When this happens, the ring buffer will detect
the corruption and then permanently disable the ring buffer.

The bug does not crash the system, but it does prevent further tracing
after the bug is hit.

Instead of reseting the trace buffers, the timestamp of the start of
the trace is used instead. The buffers will still contain the previous
data, but the output will not count any data that is before the
timestamp of the trace.

Note, this only affects the static trace output (trace) and not the
runtime trace output (trace_pipe). The runtime trace output does not
make sense for the latency tracers anyway.

Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-04 18:44:22 -04:00
Steven Rostedt
8248ac052d tracing: print out start and stop in latency traces
During development of the tracer, we would copy information from
the live tracer to the max tracer with one memcpy. Since then we
added a generic ring buffer and we handle the copies differently now.
Unfortunately, we never copied the critical section information, and
we lost the output:

 #  => started at: kmem_cache_alloc
 #  => ended at:   kmem_cache_alloc

This patch adds back the critical start and end copying as well as
removes the unused "trace_idx" and "overrun" fields of the
trace_array_cpu structure.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-09-04 11:48:12 -04:00
Steven Rostedt
5d4a9dba2d tracing: only show tracing_max_latency when latency tracer configured
The tracing_max_latency file should only be present when one of the
latency tracers ({preempt|irqs}off, wakeup*) are enabled.

This patch also removes tracing_thresh when latency tracers are not
enabled, as well as compiles out code that is only used for latency
tracers.

Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-08-27 16:58:05 -04:00
Masami Hiramatsu
ff50d99136 tracing: Kprobe tracer assigns new event ids for each event
Assign new event ids for each kprobes event. This doesn't clear
ring_buffer when unregistering each kprobe event. Thus, if you mind
'Unknown event' messages, clear the buffer manually after changing
kprobe events.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it>
Cc: Roland McGrath <roland@redhat.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
LKML-Reference: <20090813203534.31965.49105.stgit@localhost.localdomain>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-27 02:32:33 +02:00
Masami Hiramatsu
413d37d1eb tracing: Add kprobe-based event tracer
Add kprobes-based event tracer on ftrace.

This tracer is similar to the events tracer which is based on Tracepoint
infrastructure. Instead of Tracepoint, this tracer is based on kprobes
(kprobe and kretprobe). It probes anywhere where kprobes can probe(this
 means, all functions body except for __kprobes functions).

Similar to the events tracer, this tracer doesn't need to be activated
via current_tracer, instead of that, just set probe points via
/sys/kernel/debug/tracing/kprobe_events. And you can set filters on each
probe events via /sys/kernel/debug/tracing/events/kprobes/<EVENT>/filter.

This tracer supports following probe arguments for each probe.

  %REG  : Fetch register REG
  sN    : Fetch Nth entry of stack (N >= 0)
  sa    : Fetch stack address.
  @ADDR : Fetch memory at ADDR (ADDR should be in kernel)
  @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol)
  aN    : Fetch function argument. (N >= 0)
  rv    : Fetch return value.
  ra    : Fetch return address.
  +|-offs(FETCHARG) : fetch memory at FETCHARG +|- offs address.

See Documentation/trace/kprobetrace.txt in the next patch for details.

Changes from v13:
 - Support 'sa' for stack address.
 - Use call->data instead of container_of() macro.

[fweisbec@gmail.com: Fixed conflict against latest tracing/core]

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Przemysław Pawełczyk <przemyslaw@pawelczyk.it>
Cc: Roland McGrath <roland@redhat.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
LKML-Reference: <20090813203510.31965.29123.stgit@localhost.localdomain>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-27 02:31:54 +02:00
Zhaolei
5079f3261f ftrace: Move setting of clock-source out of options
There are many clock sources for the tracing system but we can only
enable/disable one at a time with the trace/options file.
We can move the setting of clock-source out of options and add a separate
file for it:
 # cat trace_clock
 [local] global
 # echo global > trace_clock
 # cat trace_clock
 local [global]

Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
LKML-Reference: <4A939D08.6050604@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-08-26 00:32:08 -04:00
Li Zefan
aa38e9fc3e tracing/filters: Add filter_type to struct ftrace_event_field
The type of a field is stored as a string in @type, and here
we add @filter_type which is an enum value.

This prepares for later patches, so we can specifically assign
different @filter_type for the same @type.

For example normally a "char *" field is treated as a ptr,
but we may want it to be treated as a string when doing filting.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4A7B925E.9030605@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-08-26 00:32:06 -04:00
Jason Baron
64c12e0444 tracing: Add individual syscalls tracepoint id support
The current state of syscalls tracepoints generates only one event id
for every syscall events.

This patch associates an id with each syscall trace event, so that we
can identify each syscall trace event using the 'perf' tool.

Signed-off-by: Jason Baron <jbaron@redhat.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Jiaying Zhang <jiayingz@google.com>
Cc: Martin Bligh <mbligh@google.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-08-11 20:35:28 +02:00
Ingo Molnar
89034bc2c7 Merge branch 'linus' into tracing/core
Conflicts:
	kernel/trace/trace_events_filter.c

We use the tracing/core version.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-11 14:19:09 +02:00
Frederic Weisbecker
f413cdb80c 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>
2009-08-09 12:53:48 +02:00
Frederic Weisbecker
1a0799a8fe tracing/function-graph-tracer: Move graph event insertion helpers in the graph tracer file
The function graph events helpers which insert the function entry and
return events into the ring buffer currently reside in trace.c
But this file is quite overloaded and the right place for these helpers
is in the function graph tracer file.

Then move them to trace_functions_graph.c

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
2009-08-06 07:28:06 +02:00
Frederic Weisbecker
c0a0d0d3f6 tracing/core: Make the stack entry helpers global
Make the stacktrace event insertion helpers globals.
This has two effects:

- Prepare for moving the sched events insertion helpers to
  the sched switch tracer file.
- Move some ifdef outside function definitions

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
2009-08-06 07:28:05 +02:00
Frederic Weisbecker
5e5bf48398 tracing/core: Turn ftrace_cpu_disabled into a global var
In order to prepare the moving of the function graph tracer insertion
helpers from trace.c to trace_functions_graph.c, we need to export the
ftrace_cpu_disabled variable.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
2009-08-06 07:28:05 +02:00
Li Zefan
1f9963cbb0 tracing/filters: improve subsystem filter
Currently a subsystem filter should be applicable to all events
under the subsystem, and if it failed, all the event filters
will be cleared. Those behaviors make subsys filter much less
useful:

  # echo 'vec == 1' > irq/softirq_entry/filter
  # echo 'irq == 5' > irq/filter
  bash: echo: write error: Invalid argument
  # cat irq/softirq_entry/filter
  none

I'd expect it set the filter for irq_handler_entry/exit, and
not touch softirq_entry/exit.

The basic idea is, try to see if the filter can be applied
to which events, and then just apply to the those events:

  # echo 'vec == 1' > softirq_entry/filter
  # echo 'irq == 5' > filter
  # cat irq_handler_entry/filter
  irq == 5
  # cat softirq_entry/filter
  vec == 1

Changelog for v2:
- do some cleanups to address Frederic's comments.

Inspired-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4A63D485.7030703@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-07-20 13:29:19 -04:00
Li Zefan
db59504d89 ksym_tracer: Extract trace entry from struct trace_ksym
struct trace_ksym is used as an entry in hbp list, and is also
used as trace_entry stored in ring buffer.

This is not necessary and is a waste of memory in ring buffer.

There is also a bug that dereferencing field->ksym_hbp in
ksym_trace_output() can be invalid.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: "K.Prasad" <prasad@linux.vnet.ibm.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <4A52E2A4.4050007@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-10 11:59:40 +02:00
Xiao Guangrong
dc82ec98a4 tracing/filter: Remove empty subsystem and its directory
Remove empty subsystem and its directory when module unload.

Before patch:
 # rmmod trace-events-sample.ko
 # ls sample
 enable  filter

After patch:
 # rmmod trace-events-sample.ko
 # ls sample
 ls: cannot access sample: No such file or directory

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Acked-by: Tom Zanussi <tzanussi@gmail.com>
Reviewed-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <4A55A8BE.9010707@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-10 11:55:28 +02:00
Li Zefan
020e5f85cb tracing/events: Add trace_event boot option
We already have ftrace= boot option, and this adds a similar
boot option for trace events, so allow trace events to be
enabled at boot, for boot debugging purpose.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4A4ACE29.3010407@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-01 15:44:24 +02:00
Paul Mundt
1155de47cd ring-buffer: Make it generally available
In hunting down the cause for the hwlat_detector ring buffer spew in
my failed -next builds it became obvious that folks are now treating
ring_buffer as something that is generic independent of tracing and thus,
suitable for public driver consumption.

Given that there are only a few minor areas in ring_buffer that have any
reliance on CONFIG_TRACING or CONFIG_FUNCTION_TRACER, provide stubs for
those and make it generally available.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Cc: Jon Masters <jcm@jonmasters.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <20090625053012.GB19944@linux-sh.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-06-25 10:31:30 +02:00
K.Prasad
0722db015c hw-breakpoints: ftrace plugin for kernel symbol tracing using HW Breakpoint interfaces
This patch adds an ftrace plugin to detect and profile memory access over kernel
variables. It uses HW Breakpoint interfaces to 'watch memory addresses.

Signed-off-by: K.Prasad <prasad@linux.vnet.ibm.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2009-06-02 22:47:00 +02:00