Commit Graph

25 Commits

Author SHA1 Message Date
Ingo Molnar 0ad5d703c6 Merge branch 'tracing/hw-branch-tracing' into tracing/core
Merge reason: this topic is ready for upstream now. It passed
              Oleg's review and Andrew had no further mm/*
              objections/observations either.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-05-07 13:36:22 +02:00
Tom Zanussi eb02ce017d tracing/filters: use ring_buffer_discard_commit() in filter_check_discard()
This patch changes filter_check_discard() to make use of the new
ring_buffer_discard_commit() function and modifies the current users to
call the old commit function in the non-discard case.

It also introduces a version of filter_check_discard() that uses the
global trace buffer (filter_current_check_discard()) for those cases.

v2 changes:

- fix compile error noticed by Ingo Molnar

Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: fweisbec@gmail.com
LKML-Reference: <1239178554.10295.36.camel@tropicana>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-14 00:00:56 +02:00
Tom Zanussi e1112b4d96 tracing/filters: add run-time field descriptions to TRACE_EVENT_FORMAT events
This patch adds run-time field descriptions to all the event formats
exported using TRACE_EVENT_FORMAT.  It also hooks up all the tracers
that use them (i.e. the tracers in the 'ftrace subsystem') so they can
also have their output filtered by the event-filtering mechanism.

When I was testing this, there were a couple of things that fooled me
into thinking the filters weren't working, when actually they were -
I'll mention them here so others don't make the same mistakes (and file
bug reports. ;-)

One is that some of the tracers trace multiple events e.g. the
sched_switch tracer uses the context_switch and wakeup events, and if
you don't set filters on all of the traced events, the unfiltered output
from the events without filters on them can make it look like the
filtering as a whole isn't working properly, when actually it is doing
what it was asked to do - it just wasn't asked to do the right thing.

The other is that for the really high-volume tracers e.g. the function
tracer, the volume of filtered events can be so high that it pushes the
unfiltered events out of the ring buffer before they can be read so e.g.
cat'ing the trace file repeatedly shows either no output, or once in
awhile some output but that isn't there the next time you read the
trace, which isn't what you normally expect when reading the trace file.
If you read from the trace_pipe file though, you can catch them before
they disappear.

Changes from v1:

As suggested by Frederic Weisbecker:

- get rid of externs in functions
- added unlikely() to filter_check_discard()

Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-14 00:00:50 +02:00
Markus Metzger de79f54f53 x86, bts, hw-branch-tracer: add _noirq variants to the debug store interface
The hw-branch-tracer uses debug store functions from an on_each_cpu()
context, which is simply wrong since the functions may sleep.

Add _noirq variants for most functions, which  may be called with
interrupts disabled.

Separate per-cpu and per-task tracing and allow per-cpu tracing to be
controlled from any cpu.

Make the hw-branch-tracer use the new debug store interface, synchronize
with hotplug cpu event using get/put_online_cpus(), and remove the
unnecessary spinlock.

Make the ptrace bts and the ds selftest code use the new interface.

Defer the ds selftest.

Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Cc: roland@redhat.com
Cc: eranian@googlemail.com
Cc: oleg@redhat.com
Cc: juan.villacis@intel.com
Cc: ak@linux.jf.intel.com
LKML-Reference: <20090403144555.658136000@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-07 13:36:20 +02:00
Ingo Molnar e9a22d1fb9 x86, bts: cleanups
Impact: cleanup, no code changed

Cc: Markus Metzger <markus.t.metzger@intel.com>
LKML-Reference: <20090313104218.A30096@sedona.ch.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-13 11:57:22 +01:00
Markus Metzger 321bb5e1ac x86, hw-branch-tracer: add selftest
Add a selftest for the hw-branch-tracer.

Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
LKML-Reference: <20090313105027.A30183@sedona.ch.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-13 11:57:21 +01:00
Markus Metzger ba9372a8f3 x86, hw-branch-tracer: keep resources on stop
Distinguish init/reset and start/stop:

init/reset will allocate and release bts tracing resources
stop/start will suspend and resume bts tracing

Return an error on init() if no cpu can be traced.

Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
LKML-Reference: <20090313104852.A30168@sedona.ch.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-13 11:57:21 +01:00
Ingo Molnar 2d542cf342 tracing/hw-branch-tracing: convert bts-tracer mutex to a spinlock
Impact: fix CPU hotplug lockup

bts_hotcpu_handler() is called with irqs disabled, so using mutex_lock()
is a no-no.

All the BTS codepaths here are atomic (they do not schedule), so using
a spinlock is the right solution.

Cc: Markus Metzger <markus.t.metzger@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-25 09:16:01 +01:00
Markus Metzger 5e01cb695d x86, ftrace: fix section mismatch in hw-branch-tracer
Fix an invalid memory reference problem when cpu hotplug support is
disabled and the hw-branch-tracer is set as current tracer.

Initializing the tracer calls bts_trace_init() which has already
been freed at this time.

Reported-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-24 18:23:34 +01:00
Rakib Mullick a234aa9ecd tracing: fix section mismatch in trace_hw_branches.c
The function bts_trace_init() references a variable
bts_hotcpu_notifier which is marked
as __cpuinitdata. Thus causes section mismatch. This patch fixes it.

   LD      kernel/trace/built-in.o
 WARNING: kernel/trace/built-in.o(.text+0xc90c): Section mismatch in
 reference from the function bts_trace_init() to the variable
 .cpuinit.data:bts_hotcpu_notifier
 The function bts_trace_init() references
 the variable __cpuinitdata bts_hotcpu_notifier.
 This is often because bts_trace_init lacks a __cpuinitdata
 annotation or the annotation of bts_hotcpu_notifier is wrong.

 WARNING: kernel/trace/built-in.o(.text+0xc92a): Section mismatch in
 reference from the function bts_trace_reset() to the variable
 .cpuinit.data:bts_hotcpu_notifier
 The function bts_trace_reset() references
 the variable __cpuinitdata bts_hotcpu_notifier.
 This is often because bts_trace_reset lacks a __cpuinitdata
 annotation or the annotation of bts_hotcpu_notifier is wrong.

Signed-off-by: Rakib Mullick <rakib.mullick@gmail.com>
Cc: markus.t.metzger@gmail.com
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-15 20:41:08 +01:00
Wenji Huang c3706f005c tracing: fix typos in comments
Impact: clean up.

Fix typos in the comments.

Signed-off-by: Wenji Huang <wenji.huang@oracle.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
2009-02-10 12:32:35 -05:00
Ingo Molnar 44b0635481 Merge branch 'tip/tracing/core/devel' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into tracing/ftrace
Conflicts:
	kernel/trace/trace_hw_branches.c
2009-02-09 10:35:12 +01:00
Steven Rostedt 1830b52d0d trace: remove deprecated entry->cpu
Impact: fix to prevent developers from using entry->cpu

With the new ring buffer infrastructure, the cpu for the entry is
implicit with which CPU buffer it is on.

The original code use to record the current cpu into the generic
entry header, which can be retrieved by entry->cpu. When the
ring buffer was introduced, the users were convert to use the
the cpu number of which cpu ring buffer was in use (this was passed
to the tracers by the iterator: iter->cpu).

Unfortunately, the cpu item in the entry structure was never removed.
This allowed for developers to use it instead of the proper iter->cpu,
unknowingly, using an uninitialized variable. This was not the fault
of the developers, since it would seem like the logical place to
retrieve the cpu identifier.

This patch removes the cpu item from the entry structure and fixes
all the users that should have been using iter->cpu.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
2009-02-07 19:38:43 -05:00
Arnaldo Carvalho de Melo b6f11df26f trace: Call tracing_reset_online_cpus before tracer->init()
Impact: cleanup

To make it easy for ftrace plugin writers, as this was open coded in
the existing plugins

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Frédéric Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-06 01:01:41 +01:00
Arnaldo Carvalho de Melo 51a763dd84 tracing: Introduce trace_buffer_{lock_reserve,unlock_commit}
Impact: new API

These new functions do what previously was being open coded, reducing
the number of details ftrace plugin writers have to worry about.

It also standardizes the handling of stacktrace, userstacktrace and
other trace options we may introduce in the future.

With this patch, for instance, the blk tracer (and some others already
in the tree) can use the "userstacktrace" /d/tracing/trace_options
facility.

$ codiff /tmp/vmlinux.before /tmp/vmlinux.after
linux-2.6-tip/kernel/trace/trace.c:
  trace_vprintk              |   -5
  trace_graph_return         |  -22
  trace_graph_entry          |  -26
  trace_function             |  -45
  __ftrace_trace_stack       |  -27
  ftrace_trace_userstack     |  -29
  tracing_sched_switch_trace |  -66
  tracing_stop               |   +1
  trace_seq_to_user          |   -1
  ftrace_trace_special       |  -63
  ftrace_special             |   +1
  tracing_sched_wakeup_trace |  -70
  tracing_reset_online_cpus  |   -1
 13 functions changed, 2 bytes added, 355 bytes removed, diff: -353

linux-2.6-tip/block/blktrace.c:
  __blk_add_trace |  -58
 1 function changed, 58 bytes removed, diff: -58

linux-2.6-tip/kernel/trace/trace.c:
  trace_buffer_lock_reserve  |  +88
  trace_buffer_unlock_commit |  +86
 2 functions changed, 174 bytes added, diff: +174

/tmp/vmlinux.after:
 16 functions changed, 176 bytes added, 413 bytes removed, diff: -237

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Frédéric Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-06 01:01:41 +01:00
Arnaldo Carvalho de Melo 0a9877514c ring_buffer: remove unused flags parameter
Impact: API change, cleanup

>From ring_buffer_{lock_reserve,unlock_commit}.

$ codiff /tmp/vmlinux.before /tmp/vmlinux.after
linux-2.6-tip/kernel/trace/trace.c:
  trace_vprintk              |  -14
  trace_graph_return         |  -14
  trace_graph_entry          |  -10
  trace_function             |   -8
  __ftrace_trace_stack       |   -8
  ftrace_trace_userstack     |   -8
  tracing_sched_switch_trace |   -8
  ftrace_trace_special       |  -12
  tracing_sched_wakeup_trace |   -8
 9 functions changed, 90 bytes removed, diff: -90

linux-2.6-tip/block/blktrace.c:
  __blk_add_trace |   -1
 1 function changed, 1 bytes removed, diff: -1

/tmp/vmlinux.after:
 10 functions changed, 91 bytes removed, diff: -91

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Frédéric Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-06 01:01:40 +01:00
Markus Metzger 11edda0628 x86, ftrace, hw-branch-tracer: change trace format
Change the hw-branch-tracer format to be more readable.

Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-20 13:04:16 +01:00
Markus Metzger e23b8ad834 x86, ftrace, hw-branch-tracer: reset trace buffer on close
Reset the ftrace buffer on close. Since we use cyclic buffers, the
trace is not contiguous, anyway.

Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-20 13:03:55 +01:00
Markus Metzger b1818748b0 x86, ftrace, hw-branch-tracer: dump trace on oops
Dump the branch trace on an oops (based on ftrace_dump_on_oops).

Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-20 13:03:48 +01:00
Markus Metzger 5c5317de14 x86, ftrace, hw-branch-tracer: support hotplug cpus
Support hotplug cpus.

Reported-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-20 13:03:38 +01:00
Ingo Molnar 99793e3dbe Merge branches 'tracing/kmemtrace2' and 'tracing/ftrace' into tracing/urgent 2009-01-06 10:18:43 +01:00
Rusty Russell 4462344ee9 cpumask: convert kernel trace functions further
Impact: Reduce future memory usage, use new cpumask API.

Since the last patch was created and acked, more old cpumask users
slipped into kernel/trace.

Mostly trivial conversions, except struct trace_iterator's "started"
member becomes a cpumask_var_t.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-01-01 10:12:23 +10:30
Steven Rostedt f0868d1e23 ftrace: set up trace event hash infrastructure
Impact: simplify/generalize/refactor trace.c

The trace.c file is becoming more difficult to maintain due to the
growing number of events. There is several formats that an event may
be printed. This patch sets up the infrastructure of an event hash to
allow for events to register how they should be printed.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-29 12:46:11 +01:00
Pekka J Enberg 213cc06079 ftrace: introduce tracing_reset_online_cpus() helper
Impact: cleanup

This patch factors out common code from multiple tracers into a
tracing_reset_online_cpus() function and converts the tracers to use it.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-19 16:29:34 +01:00
Markus Metzger a93751cab7 x86, bts, ftrace: adapt the hw-branch-tracer to the ds.c interface
Impact: restructure code, cleanup

Remove BTS bits from the hw-branch-tracer (renamed from bts-tracer) and
use the ds interface.

Signed-off-by: Markus Metzger <markut.t.metzger@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-12 08:08:14 +01:00