Allow a user to select which fields to print to stdout for event data.
Options include comm (command name), tid (thread id), pid (process id),
time (perf timestamp), cpu, event (for event name), and trace (for
trace data).
Default is set to maintain compatibility with current output; this
feature does alter output format slightly -- no '-' between command
and pid/tid.
Thanks to Frederic Weisbecker for detailed suggestions on this approach.
Examples (output compressed)
1. trace, default format
perf record -ga -e sched:sched_switch
perf script
swapper 0 [000] 537.037184: sched_switch: prev_comm=swapper prev_pid=0...
sshd 1675 [000] 537.037309: sched_switch: prev_comm=sshd prev_pid=1675...
netstat 1692 [001] 537.038664: sched_switch: prev_comm=netstat prev_pid=1692...
2. trace, custom format
perf record -ga -e sched:sched_switch
perf script -f comm,pid,time,trace <--- omitting cpu and event name
swapper 0 537.037184: prev_comm=swapper prev_pid=0 prev_prio=120 ...
sshd 1675 537.037309: prev_comm=sshd prev_pid=1675 prev_prio=120 ...
netstat 1692 537.038664: prev_comm=netstat prev_pid=1692 prev_prio=120 ...
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <1299734608-5223-5-git-send-email-daahern@cisco.com>
Signed-off-by: David Ahern <daahern@cisco.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
While going thru each of the sym_entry fields looking to reduce it to
the set of entries needed when in an active symbols list, 'skip' should
really be in symbol, as we set it when loading the symtab.
And the space used by the basic symbol allocation remains the same as
we had 5 bytes of padding.
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
If the kernel command line declares a tracer "ftrace=sometracer" and
that tracer is either not defined or is enabled after irqsoff,
then the irqs off selftest will fail with the following error:
Testing tracer irqsoff:
------------[ cut here ]------------
WARNING: at /home/rostedt/work/autotest/nobackup/linux-test.git/kernel/trace/tra
ce.c:713 update_max_tr_single+0xfa/0x11b()
Hardware name:
Modules linked in:
Pid: 1, comm: swapper Not tainted 2.6.38-rc8-test #1
Call Trace:
[<c0441d9d>] ? warn_slowpath_common+0x65/0x7a
[<c049adb2>] ? update_max_tr_single+0xfa/0x11b
[<c0441dc1>] ? warn_slowpath_null+0xf/0x13
[<c049adb2>] ? update_max_tr_single+0xfa/0x11b
[<c049e454>] ? stop_critical_timing+0x154/0x204
[<c049b54b>] ? trace_selftest_startup_irqsoff+0x5b/0xc1
[<c049b54b>] ? trace_selftest_startup_irqsoff+0x5b/0xc1
[<c049b54b>] ? trace_selftest_startup_irqsoff+0x5b/0xc1
[<c049e529>] ? time_hardirqs_on+0x25/0x28
[<c0468bca>] ? trace_hardirqs_on_caller+0x18/0x12f
[<c0468cec>] ? trace_hardirqs_on+0xb/0xd
[<c049b54b>] ? trace_selftest_startup_irqsoff+0x5b/0xc1
[<c049b6b8>] ? register_tracer+0xf8/0x1a3
[<c14e93fe>] ? init_irqsoff_tracer+0xd/0x11
[<c040115e>] ? do_one_initcall+0x71/0x121
[<c14e93f1>] ? init_irqsoff_tracer+0x0/0x11
[<c14ce3a9>] ? kernel_init+0x13a/0x1b6
[<c14ce26f>] ? kernel_init+0x0/0x1b6
[<c0403842>] ? kernel_thread_helper+0x6/0x10
---[ end trace e93713a9d40cd06c ]---
.. no entries found ..FAILED!
What happens is the "ftrace=..." will expand the ring buffer to its
default size (from its minimum size) but it will not expand the
max ring buffer (the ring buffer to store maximum latencies).
When the irqsoff test runs, it will call the ring buffer swap routine
that checks if the max ring buffer is the same size as the normal
ring buffer, and will fail if it is not. This causes the test to fail.
The solution is to expand the max ring buffer before running the self
test if the max ring buffer is used by that tracer and the normal ring
buffer is expanded. The max ring buffer should be shrunk again after
the test is done to save space.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
The "Delta way too big" warning might appear on a system with a
unstable shed clock right after the system is resumed and tracing
was enabled at time of suspend.
Since it's not realy a bug, and the unstable sched clock is working
fast and reliable otherwise, Steven suggested to keep using the
sched clock in any case and just to make note in the warning itself.
v2 changes:
- added #ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
LKML-Reference: <20110218145219.GD2604@jolsa.brq.redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Currently the index to the ret_stack is updated and the real return address
is saved in the ret_stack. Then we call the trace function. The trace
function could decide that it doesn't want to trace this function
(ex. set_graph_function does not match) and it will return 0 which means
not to trace this call.
The normal function graph tracer has this code:
if (!(trace->depth || ftrace_graph_addr(trace->func)) ||
ftrace_graph_ignore_irqs())
return 0;
What this states is, if the trace depth (which is curr_ret_stack)
is zero (top of nested functions) then test if we want to trace this
function. If this function is not to be traced, then return 0 and
the rest of the function graph tracer logic will not trace this function.
The problem arises when an interrupt comes in after we updated the
curr_ret_stack. The next function that gets called will have a trace->depth
of 1. Which fools this trace code into thinking that we are in a nested
function, and that we should trace. This causes interrupts to be traced
when they should not be.
The solution is to trace the function first and then update the ret_stack.
Reported-by: zhiping zhong <xzhong86@163.com>
Reported-by: wu zhangjin <wuzhangjin@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
The section .ref.text will not go away unexpectedly and is
safe to trace. Add it to the safe list of sections to allow
tracing.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
The lock_depth field in the event headers was added as a temporary
data point for help in removing the BKL. Now that the BKL is pretty
much been removed, we can remove this field.
This in turn changes the header from 12 bytes to 8 bytes,
removing the 4 byte buffer that gcc would insert if the first field
in the data load was 8 bytes in size.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
So that we can reuse things like the id to attr lookup routine
(perf_evlist__id2evsel) that uses a hash table instead of the linear
lookup done in the older perf_header_attr routines, etc.
Also to make evsels/evlist more pervasive an API, simplyfing using the
emerging perf lib.
cc: Arun Sharma <arun@sharma-home.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
David Ahern
Frederic Weisbecker
Arnaldo Carvalho de Melo
Ingo Molnar
Steven Rostedt
Yuanhan Liu
Jiri Olsa
David Sharp