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* ftrace, sched: Add TRACE_FLAG_PREEMPT_RESCHEDPeter Zijlstra2013-11-111-1/+5
| | | | | | | | | | | | | | | | | | | Since the introduction of PREEMPT_NEED_RESCHED in: f27dde8deef3 ("sched: Add NEED_RESCHED to the preempt_count") we need to be able to look at both TIF_NEED_RESCHED and PREEMPT_NEED_RESCHED to understand the full preemption behaviour. Add it to the trace output. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Huang Ying <ying.huang@intel.com> Cc: Yuanhan Liu <yuanhan.liu@linux.intel.com> Link: http://lkml.kernel.org/r/20131004152826.GP3081@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
* Documentation: replace strict_strtoul() with kstrtoul()Jingoo Han2013-08-201-2/+2
| | | | | | | | | The usage of strict_strtoul() is not preferred, because strict_strtoul() is obsolete. Thus, kstrtoul() should be used. Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* tracing: Add function probe to trigger a ftrace dump of current CPU traceSteven Rostedt (Red Hat)2013-06-111-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | Add the "cpudump" command to have the current CPU ftrace buffer dumped to console if a function is hit. This is useful when debugging a tripple fault, where you have an idea of a function that is called just before the tripple fault occurs, and can tell ftrace to dump its content out to the console before it continues. This differs from the "dump" command as it only dumps the content of the ring buffer for the currently executing CPU, and does not show the contents of the other CPUs. Format is: <function>:cpudump echo 'bad_address:cpudump' > /debug/tracing/set_ftrace_filter To remove this: echo '!bad_address:cpudump' > /debug/tracing/set_ftrace_filter Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Add function probe to trigger a ftrace dump to consoleSteven Rostedt (Red Hat)2013-06-111-0/+7
| | | | | | | | | | | | | | | | | | | | | Add the "dump" command to have the ftrace buffer dumped to console if a function is hit. This is useful when debugging a tripple fault, where you have an idea of a function that is called just before the tripple fault occurs, and can tell ftrace to dump its content out to the console before it continues. Format is: <function>:dump echo 'bad_address:dump' > /debug/tracing/set_ftrace_filter To remove this: echo '!bad_address:dump' > /debug/tracing/set_ftrace_filter Requested-by: Luis Claudio R. Goncalves <lclaudio@uudg.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Bring Documentation/trace/ftrace.txt up to dateSteven Rostedt (Red Hat)2013-03-151-617/+1480
| | | | | | | | | | | | | | | The ftrace.txt document has been suffering from some serious bit rot. Updated the current content to how things are as of v3.10. Remove things that no longer exist. Add documentation about new features: per_cpu stats instances stack trace etc. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: update documentation of snapshot utilityHiraku Toyooka2013-03-081-1/+1
| | | | | | | | | | | Now, "snapshot" file returns success on a reset of snapshot buffer even if the buffer wasn't allocated, instead of returning EINVAL. This patch updates snapshot desctiption according to the change. Link: http://lkml.kernel.org/r/51399409.4090207@hitachi.com Signed-off-by: Hiraku Toyooka <hiraku.toyooka.gu@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Add documentation of snapshot utilityHiraku Toyooka2013-01-301-0/+83
| | | | | | | | | | | This patch adds snapshot description in ftrace documentation. This description includes what the snapshot is and how to use it. Link: http://lkml.kernel.org/r/20121226025309.3252.150.stgit@liselsia Cc: Rob Landley <rob@landley.net> Signed-off-by: Hiraku Toyooka <hiraku.toyooka.gu@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* ftrace: Append wakeup_rt description of ftrace docGeunsik Lim2012-02-131-0/+7
| | | | | | | | | | Append and update the description about wakeup/wakeup_rt usage. Link: http://lkml.kernel.org/r/1328695537-15081-2-git-send-email-geunsik.lim@gmail.com Cc: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Geunsik Lim <geunsik.lim@samsung.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Add an 'overwrite' trace_option.David Sharp2011-03-091-0/+5
| | | | | | | | | | | | Add an "overwrite" trace_option for ftrace to control whether the buffer should be overwritten on overflow or not. The default remains to overwrite old events when the buffer is full. This patch adds the option to instead discard newest events when the buffer is full. This is useful to get a snapshot of traces just after enabling traces. Dropping the current event is also a simpler code path. Signed-off-by: David Sharp <dhsharp@google.com> LKML-Reference: <1291844807-15481-1-git-send-email-dhsharp@google.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Deprecate tracing_enabled for tracing_onSteven Rostedt2011-02-081-19/+19
| | | | | | | | | | | tracing_enabled should not be used, it is heavy weight and does not do much in helping lower the overhead. tracing_on should be used instead. Warn users to use tracing_on when tracing_enabled is used as it will soon be removed from the tracing directory. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Remove obsolete sched_switch tracerSteven Rostedt2011-02-081-110/+0
| | | | | | | The trace events sched_switch and sched_wakeup do the same thing as the stand alone sched_switch tracer does. It is no longer needed. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Add documentation for trace commands mod, traceon/traceoffChase Douglas2010-04-271-0/+44
| | | | | | | | | | | | The mod command went in as commit 64e7c440618998fd69eee6ab490b042d12248021 The traceon/traceoff commands went in as commit 23b4ff3aa479c9e3bb23cb6b2d0a97878399784a Signed-off-by: Chase Douglas <chase.douglas@canonical.com> LKML-Reference: <1272045759-32018-1-git-send-email-chase.douglas@canonical.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Dump either the oops's cpu source or all cpus buffersFrederic Weisbecker2010-04-211-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The ftrace_dump_on_oops kernel parameter, sysctl and sysrq let one dump every cpu buffers when an oops or panic happens. It's nice when you have few cpus but it may take ages if have many, plus you miss the real origin of the problem in all the cpu traces. Sometimes, all you need is to dump the cpu buffer that triggered the opps, most of the time it is our main interest. This patch modifies ftrace_dump_on_oops to handle this choice. The ftrace_dump_on_oops kernel parameter, when it comes alone, has the same behaviour than before. But ftrace_dump_on_oops=orig_cpu will only dump the buffer of the cpu that oops'ed. Similarly, sysctl kernel.ftrace_dump_on_oops=1 and echo 1 > /proc/sys/kernel/ftrace_dump_on_oops keep their previous behaviour. But setting 2 jumps into cpu origin dump mode. v2: Fix double setup v3: Fix spelling issues reported by Randy Dunlap v4: Also update __ftrace_dump in the selftests Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
* tree-wide: Assorted spelling fixesDaniel Mack2010-02-091-1/+1
| | | | | | | | | | | In particular, several occurances of funny versions of 'success', 'unknown', 'therefore', 'acknowledge', 'argument', 'achieve', 'address', 'beginning', 'desirable', 'separate' and 'necessary' are fixed. Signed-off-by: Daniel Mack <daniel@caiaq.de> Cc: Joe Perches <joe@perches.com> Cc: Junio C Hamano <gitster@pobox.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* tracing/documentation: Fix a typo in ftrace.txtYang Hongyang2010-01-261-1/+1
| | | | | | | | | | | 'ftrace' is no longer the name of the function tracer, to activate the function trace 'echo function > current_tracer' is to be used instead of 'echo ftrace > current_tracer'. Update the documentation to reflect the current implementation. Signed-off-by: Yang Hongyang <yanghy@cn.fujitsu.com> LKML-Reference: <4B5D0BA8.20106@cn.fujitsu.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Fix comment typo and documentation exampleJiri Olsa2009-10-241-0/+2
| | | | | | | | | | | Trivial patch to fix a documentation example and to fix a comment. Signed-off-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <20091023233646.871719877@goodmis.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* trivial: fix typos "man[ae]g?ment" -> "management"Uwe Kleine-Koenig2009-09-211-1/+1
| | | | | Signed-off-by: Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* ftrace: document function and function graph implementationMike Frysinger2009-09-141-0/+6
| | | | | | | | | | | | While implementing function tracer and function tracer graph support, I found the exact arch implementation details to be a bit lacking (and my x86 foo ain't great). So after pounding out support for the Blackfin arch, start documenting the requirements/details. Signed-off-by: Mike Frysinger <vapier@gentoo.org> LKML-Reference: <1252973415-21264-1-git-send-email-vapier@gentoo.org> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* tracing: Remove mentioning of legacy latency_trace file from documentationAlbin Tonnerre2009-09-041-32/+36
| | | | | | | | | | | | | | | | | | The latency_trace file got removed a while back by commit 886b5b73d71e4027d7dc6c14f5f7ab102201ea6b and has been replaced by the latency-format option. This patch fixes the documentation by reflecting this change. Changes since v1: - mention that the trace format is configurable through the latency-format option - Fix a couple mistakes related to the timestamps Signed-off-by: Albin Tonnerre <albin.tonnerre@free-electrons.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <20090831204007.GE4237@pc-ras4041.res.insa> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
* debugfs: Fix terminology inconsistency of dir name to mount debugfs filesystem.GeunSik Lim2009-06-151-91/+142
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Many developers use "/debug/" or "/debugfs/" or "/sys/kernel/debug/" directory name to mount debugfs filesystem for ftrace according to ./Documentation/tracers/ftrace.txt file. And, three directory names(ex:/debug/, /debugfs/, /sys/kernel/debug/) is existed in kernel source like ftrace, DRM, Wireless, Documentation, Network[sky2]files to mount debugfs filesystem. debugfs means debug filesystem for debugging easy to use by greg kroah hartman. "/sys/kernel/debug/" name is suitable as directory name of debugfs filesystem. - debugfs related reference: http://lwn.net/Articles/334546/ Fix inconsistency of directory name to mount debugfs filesystem. * From Steven Rostedt - find_debugfs() and tracing_files() in this patch. Signed-off-by: GeunSik Lim <geunsik.lim@samsung.com> Acked-by : Inaky Perez-Gonzalez <inaky@linux.intel.com> Reviewed-by : Steven Rostedt <rostedt@goodmis.org> Reviewed-by : James Smart <james.smart@emulex.com> CC: Jiri Kosina <trivial@kernel.org> CC: David Airlie <airlied@linux.ie> CC: Peter Osterlund <petero2@telia.com> CC: Ananth N Mavinakayanahalli <ananth@in.ibm.com> CC: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> CC: Masami Hiramatsu <mhiramat@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* trivial: ftrace:fix description of trace directoryGeunSik Lim2009-06-121-1/+1
| | | | | | | Fix trace source directory from kernel/tracing/ to kernel/trace/. Signed-off-by: GeunSik Lim <geunsik.lim@samsung.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* Merge branch 'tracing-for-linus' of ↵Linus Torvalds2009-06-101-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (244 commits) Revert "x86, bts: reenable ptrace branch trace support" tracing: do not translate event helper macros in print format ftrace/documentation: fix typo in function grapher name tracing/events: convert block trace points to TRACE_EVENT(), fix !CONFIG_BLOCK tracing: add protection around module events unload tracing: add trace_seq_vprint interface tracing: fix the block trace points print size tracing/events: convert block trace points to TRACE_EVENT() ring-buffer: fix ret in rb_add_time_stamp ring-buffer: pass in lockdep class key for reader_lock tracing: add annotation to what type of stack trace is recorded tracing: fix multiple use of __print_flags and __print_symbolic tracing/events: fix output format of user stack tracing/events: fix output format of kernel stack tracing/trace_stack: fix the number of entries in the header ring-buffer: discard timestamps that are at the start of the buffer ring-buffer: try to discard unneeded timestamps ring-buffer: fix bug in ring_buffer_discard_commit ftrace: do not profile functions when disabled tracing: make trace pipe recognize latency format flag ...
| * ftrace/documentation: fix typo in function grapher nameMike Frysinger2009-06-101-1/+1
| | | | | | | | | | | | | | | | | | The function graph tracer is called just "function_graph" (no trailing "_tracer" needed). Signed-off-by: Mike Frysinger <vapier@gentoo.org> LKML-Reference: <1244623722-6325-1-git-send-email-vapier@gentoo.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* | ftrace: fix typo about map of kernel priority in ftrace.txt file.GeunSik Lim2009-05-291-3/+12
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix typo about chart to map the kernel priority to user land priorities. * About sched_setscheduler(2) Processes scheduled under SCHED_FIFO or SCHED_RR can have a (user-space) static priority in the range 1 to 99. (reference: http://www.kernel.org/doc/man-pages/online/pages/ man2/sched_setscheduler.2.html) * From: Steven Rostedt 0 to 98 - maps to RT tasks 99 to 1 (SCHED_RR or SCHED_FIFO) 99 - maps to internal kernel threads that want to be lower than RT tasks but higher than SCHED_OTHER tasks. Although I'm not sure if any kernel thread actually uses this. I'm not even sure how this can be set, because the internal sched_setscheduler function does not allow for it. 100 to 139 - maps nice levels -20 to 19. These are not set via sched_setscheduler, but are set via the nice system call. 140 - reserved for idle tasks. Signed-off-by: GeunSik Lim <geunsik.lim@samsung.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* tracing: consolidate documentsLi Zefan2009-04-091-0/+1828
Move kmemtrace.txt, tracepoints.txt, ftrace.txt and mmiotrace.txt to the new trace/ directory. I didnt find any references to those documents in both source files and documents, so no extra work needs to be done. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Pekka Paalanen <pq@iki.fi> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> LKML-Reference: <49DD6E2B.6090200@cn.fujitsu.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>