* 'tracing-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (105 commits)
ring-buffer: only enable ring_buffer_swap_cpu when needed
ring-buffer: check for swapped buffers in start of committing
tracing: report error in trace if we fail to swap latency buffer
tracing: add trace_array_printk for internal tracers to use
tracing: pass around ring buffer instead of tracer
tracing: make tracing_reset safe for external use
tracing: use timestamp to determine start of latency traces
tracing: Remove mentioning of legacy latency_trace file from documentation
tracing/filters: Defer pred allocation, fix memory leak
tracing: remove users of tracing_reset
tracing: disable buffers and synchronize_sched before resetting
tracing: disable update max tracer while reading trace
tracing: print out start and stop in latency traces
ring-buffer: disable all cpu buffers when one finds a problem
ring-buffer: do not count discarded events
ring-buffer: remove ring_buffer_event_discard
ring-buffer: fix ring_buffer_read crossing pages
ring-buffer: remove unnecessary cpu_relax
ring-buffer: do not swap buffers during a commit
ring-buffer: do not reset while in a commit
...
This patch improves some (common) inefficiencies in the
handling of directory lookups:
- not using the d_type information returned by the kernel
- constructing (absolute) paths for file operation even though
directory-relative operations using the *at functions is
possible
There are more places to fix but this is a start.
Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <20090904193951.GB6186@ghostprotocols.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Remove some, now useless, global storage.
Don't calculate the stddev when not needed.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Use the more advanced single pass variance algorithm outlined
on the wikipedia page. This is numerically more stable for
larger sample sets.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
When we're computing the mean by sampling the distribution,
then the std dev of the mean is related to the std dev of the
sample set by:
stddev_mean = std_dev / sqrt(N)
Which is exactly what we want.
This results in the error on the mean decreasing with
increasing number of samples.
Also fix the scaled == -1, aka not counted case.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Since we don't need all the individual samples to calculate the
error remove both the limit and the storage overhead associated
with that.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The current noise computation does:
\Sum abs(n_i - avg(n)) * N^-1.5
Which is (afaik) not a regular noise function, and needs the
complete sample set available to post-process.
Change this to use a regular stddev computation which can be
done by keeping a two sums:
stddev = sqrt( 1/N (\Sum n_i^2) - avg(n)^2 )
For which we only need to keep \Sum n_i and \Sum n_i^2.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: <stable@kernel.org>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This wires up the perf_counter_open() syscall so that basic
software support for perf is working.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We did not account for the enclosing \0. Depending on what malloc()
gave us this resulted in corrupted version string printouts.
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: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Leave the input fd at the data area.
It does not matter right now - but seeking at the end of it
certainly did not make sense.
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: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
We started parsing perf.data at head 0. This caused -D to
segfault and it could possibly also case incorrect trace
entries to be displayed.
Parse it at data_offset instead.
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: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Older versions of GCC are rather stupid about strict aliasing:
util/trace-event-parse.c: In function 'parse_cmdlines':
util/trace-event-parse.c:93: warning: dereferencing type-punned pointer will break strict-aliasing rules
util/trace-event-parse.c: In function 'parse_proc_kallsyms':
util/trace-event-parse.c:155: warning: dereferencing type-punned pointer will break strict-aliasing rules
util/trace-event-parse.c:157: warning: dereferencing type-punned pointer will break strict-aliasing rules
util/trace-event-parse.c:158: warning: dereferencing type-punned pointer will break strict-aliasing rules
util/trace-event-parse.c: In function 'parse_ftrace_printk':
util/trace-event-parse.c:294: warning: dereferencing type-punned pointer will break strict-aliasing rules
util/trace-event-parse.c:295: warning: dereferencing type-punned pointer will break strict-aliasing rules
make: *** [util/trace-event-parse.o] Error 1
Make it clear to GCC that we intend with those pointers, by passing
them through via an explicit (void *) cast.
We might want to add -fno-strict-aliasing as well, like the kernel
itself does.
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: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Make it easier to turn warnings on/off by using a separate
line for each warning added.
Some of the warnings have too much of a nuisance factor and
we might want to turn them off in the future.
Cc: Arjan van de Ven <arjan@infradead.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: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
In perf tools, we hardcode the pid 0 cmdline resolving to
"idle" because the init task is not included in the COMM
events.
But the idle tasks secondary cpus are resolved into their
"init" name through the COMM events.
We have then such strange result in perf report (ditto with
trace):
19.66% init [kernel] [k] acpi_idle_enter_c1
17.32% [idle] [kernel] [k] acpi_idle_enter_c1
It's then better to unify the swapper tasks into a single init
name.
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>
LKML-Reference: <1251693921-6579-3-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>
The cmd-trace tool used the cmdline file and resolved the idle
thread using a hardcoded check for the 0 task pid.
Now we have a centralized way to do that from perf using
register_idle_thread() API.
Before:
:0-0 [000] 0.000000: irq_handler_entry: irq=0 handler=name
:0-0 [000] 0.000000: irq_handler_entry: irq=0 handler=name
After:
[idle]-0 [000] 0.000000: irq_handler_entry: irq=0 handler=name
[idle]-0 [000] 0.000000: irq_handler_entry: irq=0 handler=name
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1251693921-6579-2-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Merge reason: this topic is ready now to merge into the main
development branch for .32, with functional
perf trace output.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
