Frederic Weisbecker
4903620034
tracing/ftrace: stop {irqs, preempt}soff tracers when tracing is stopped
Impact: fix a selftest warning
In some cases, it's possible to see the following warning on irqsoff
tracer selftest:
[ 4.640003] Testing tracer irqsoff: <4>------------[ cut here ]------------
[ 4.653562] WARNING: at kernel/trace/trace.c:458 update_max_tr_single+0x9a/0xc4()
[ 4.660000] Hardware name: System Product Name
[ 4.660000] Modules linked in:
[ 4.660000] Pid: 301, comm: kstop/1 Not tainted 2.6.29-rc8-tip #35837
[ 4.660000] Call Trace:
[ 4.660000] [<4014b588>] warn_slowpath+0x79/0x8f
[ 4.660000] [<402d6949>] ? put_dec+0x64/0x6b
[ 4.660000] [<40162b56>] ? getnstimeofday+0x58/0xdd
[ 4.660000] [<40162210>] ? clocksource_read+0x3/0xf
[ 4.660000] [<4015eb44>] ? ktime_set+0x8/0x34
[ 4.660000] [<4014101a>] ? balance_runtime+0x8/0x56
[ 4.660000] [<405f6f11>] ? _spin_lock+0x3/0x10
[ 4.660000] [<4011f643>] ? ftrace_call+0x5/0x8
[ 4.660000] [<4015d0f1>] ? task_cputime_zero+0x3/0x27
[ 4.660000] [<40190ee7>] ? cpupri_set+0x90/0xcb
[ 4.660000] [<405f7208>] ? _spin_lock_irqsave+0x22/0x34
[ 4.660000] [<40190f12>] ? cpupri_set+0xbb/0xcb
[ 4.660000] [<405f7151>] ? _spin_unlock_irqrestore+0x23/0x35
[ 4.660000] [<4018493f>] ? ring_buffer_reset_cpu+0x27/0x51
[ 4.660000] [<405f7208>] ? _spin_lock_irqsave+0x22/0x34
[ 4.660000] [<40184962>] ? ring_buffer_reset_cpu+0x4a/0x51
[ 4.660000] [<405f7151>] ? _spin_unlock_irqrestore+0x23/0x35
[ 4.660000] [<4018cc29>] ? trace_hardirqs_off+0x1a/0x1c
[ 4.660000] [<405f7151>] ? _spin_unlock_irqrestore+0x23/0x35
[ 4.660000] [<40184962>] ? ring_buffer_reset_cpu+0x4a/0x51
[ 4.660000] [<401850f3>] ? cpumask_next+0x15/0x18
[ 4.660000] [<4018a41f>] update_max_tr_single+0x9a/0xc4
[ 4.660000] [<4014e5fe>] ? exit_notify+0x16/0xf2
[ 4.660000] [<4018cd13>] check_critical_timing+0xcc/0x11e
[ 4.660000] [<4014e5fe>] ? exit_notify+0x16/0xf2
[ 4.660000] [<4014e5fe>] ? exit_notify+0x16/0xf2
[ 4.660000] [<4018cdf1>] stop_critical_timing+0x8c/0x9f
[ 4.660000] [<4014e5c4>] ? forget_original_parent+0xac/0xd0
[ 4.660000] [<4018ce3a>] trace_hardirqs_on+0x1a/0x1c
[ 4.660000] [<4014e5c4>] forget_original_parent+0xac/0xd0
[ 4.660000] [<4014e5fe>] exit_notify+0x16/0xf2
[ 4.660000] [<4014e8a5>] do_exit+0x1cb/0x225
[ 4.660000] [<4015c72b>] ? kthread+0x0/0x69
[ 4.660000] [<4011f61d>] kernel_thread_helper+0xd/0x10
[ 4.660000] ---[ end trace a7919e7f17c0a725 ]---
[ 4.660164] .. no entries found ..FAILED!
During the selftest of irqsoff tracer, we do that:
/* disable interrupts for a bit */
local_irq_disable();
udelay(100);
local_irq_enable();
/* stop the tracing. */
tracing_stop();
/* check both trace buffers */
ret = trace_test_buffer(tr, NULL);
If a callsite performs a new max delay with irqs off just after
tracing_stop, update_max_tr_single() -> ring_buffer_swap_cpu()
will be called with the buffers disabled by tracing_stop(), hence
the warning, then ring_buffer_swap_cpu() return -EAGAIN and
update_max_tr_single() complains.
Fix it by also stopping the tracer before stopping the tracing globally.
A similar situation can happen with preemptoff and preemptirqsoff tracers
where we apply the same fix.
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <1237325938-5240-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
2009-03-18 10:12:38 +01:00 |
| .. |
|
blktrace.c
|
tracing: protect reader of cmdline output
|
2009-03-16 23:27:06 -04:00 |
|
events.c
|
tracing: use generic __stringify
|
2009-03-10 00:35:05 -04:00 |
|
ftrace.c
|
tracing/ftrace: fix the check on nopped sites
|
2009-03-16 22:15:36 -04:00 |
|
Kconfig
|
tracing/syscalls: select kallsysms
|
2009-03-16 09:13:17 +01:00 |
|
kmemtrace.c
|
tracing: Introduce trace_buffer_{lock_reserve,unlock_commit}
|
2009-02-06 01:01:41 +01:00 |
|
Makefile
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tracing/ftrace: syscall tracing infrastructure, basics
|
2009-03-13 06:25:43 +01:00 |
|
ring_buffer.c
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ring-buffer: add api to allow a tracer to change clock source
|
2009-03-17 23:06:31 -04:00 |
|
trace.c
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Merge branch 'tip/tracing/ftrace' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into tracing/ftrace
|
2009-03-18 06:59:56 +01:00 |
|
trace.h
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Merge branch 'tip/tracing/ftrace' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into tracing/ftrace
|
2009-03-18 06:59:56 +01:00 |
|
trace_boot.c
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tracing: Introduce trace_buffer_{lock_reserve,unlock_commit}
|
2009-02-06 01:01:41 +01:00 |
|
trace_branch.c
|
tracing: remove funky whitespace in the trace code
|
2009-03-10 14:13:14 -04:00 |
|
trace_clock.c
|
trace_clock: fix preemption bug
|
2009-03-10 20:03:01 +01:00 |
|
trace_event_types.h
|
tracing: make bprint event use the proper event id
|
2009-03-12 21:15:00 -04:00 |
|
trace_events.c
|
tracing: fix leak in event_format_read()
|
2009-03-17 08:38:23 +01:00 |
|
trace_events_stage_1.h
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tracing: update comments to match event code macros
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2009-03-10 13:12:58 -04:00 |
|
trace_events_stage_2.h
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tracing: show event name in trace for TRACE_EVENT created events
|
2009-03-12 22:00:19 -04:00 |
|
trace_events_stage_3.h
|
tracing: remove funky whitespace in the trace code
|
2009-03-10 14:13:14 -04:00 |
|
trace_export.c
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tracing: remove funky whitespace in the trace code
|
2009-03-10 14:13:14 -04:00 |
|
trace_functions.c
|
tracing/core: use appropriate waiting on trace_pipe
|
2009-02-18 01:40:20 +01:00 |
|
trace_functions_graph.c
|
tracing: protect reader of cmdline output
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2009-03-16 23:27:06 -04:00 |
|
trace_hw_branches.c
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tracing/hw-branch-tracing: convert bts-tracer mutex to a spinlock
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2009-02-25 09:16:01 +01:00 |
|
trace_irqsoff.c
|
tracing: have latency tracers set the latency format
|
2009-03-04 22:15:30 -05:00 |
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trace_mmiotrace.c
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tracing/core: bring back raw trace_printk for dynamic formats strings
|
2009-03-12 21:15:00 -04:00 |
|
trace_nop.c
|
trace: Call tracing_reset_online_cpus before tracer->init()
|
2009-02-06 01:01:41 +01:00 |
|
trace_output.c
|
tracing: protect reader of cmdline output
|
2009-03-16 23:27:06 -04:00 |
|
trace_output.h
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tracing/core: drop the old trace_printk() implementation in favour of trace_bprintk()
|
2009-03-06 17:59:12 +01:00 |
|
trace_power.c
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tracing: make power tracer start/stop methods lighter weight
|
2009-03-17 23:12:11 -04:00 |
|
trace_printk.c
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tracing: export trace formats to user space
|
2009-03-12 21:15:01 -04:00 |
|
trace_sched_switch.c
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tracing: make sched_switch stop/start light weight
|
2009-03-17 23:10:45 -04:00 |
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trace_sched_wakeup.c
|
tracing: have latency tracers set the latency format
|
2009-03-04 22:15:30 -05:00 |
|
trace_selftest.c
|
tracing/ftrace: stop {irqs, preempt}soff tracers when tracing is stopped
|
2009-03-18 10:12:38 +01:00 |
|
trace_selftest_dynamic.c
|
ftrace: fix dynamic ftrace selftest
|
2008-05-23 21:13:23 +02:00 |
|
trace_stack.c
|
tracing: left align location header in stack_trace
|
2009-03-13 00:00:58 -04:00 |
|
trace_stat.c
|
tracing: fix typing mistake in hint message and comments
|
2009-02-17 12:38:24 -05:00 |
|
trace_stat.h
|
tracing/ftrace: separate events tracing and stats tracing engine
|
2009-01-14 12:11:37 +01:00 |
|
trace_syscalls.c
|
tracing/syscalls: protect thread flag toggling from races
|
2009-03-16 09:13:16 +01:00 |
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trace_sysprof.c
|
tracing: make all file_operations const
|
2009-03-05 21:46:40 -05:00 |
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trace_workqueue.c
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tracing: Don't use tracing_record_cmdline() in workqueue tracer fix
|
2009-03-12 21:23:47 -04:00 |