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2016-03-08tracing: Fix typoes in code comment and printk in trace_nop.cChunyu Hu1-2/+2
echo nop > /sys/kernel/debug/tracing/options/current_tracer echo 1 > /sys/kernel/debug/tracing/options/test_nop_accept echo 0 > /sys/kernel/debug/tracing/options/test_nop_accept echo 1 > /sys/kernel/debug/tracing/options/test_nop_refuse Before the fix, the dmesg is a bit ugly since a align issue. [ 191.973081] nop_test_accept flag set to 1: we accept. Now cat trace_options to see the result [ 195.156942] nop_test_refuse flag set to 1: we refuse.Now cat trace_options to see the result After the fix, the dmesg will show aligned log for nop_test_refuse and nop_test_accept. [ 2718.032413] nop_test_refuse flag set to 1: we refuse. Now cat trace_options to see the result [ 2734.253360] nop_test_accept flag set to 1: we accept. Now cat trace_options to see the result Link: http://lkml.kernel.org/r/1457444222-8654-2-git-send-email-chuhu@redhat.com Signed-off-by: Chunyu Hu <chuhu@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-01-22tracing: Remove unneeded includes of debugfs.h and fs.hSteven Rostedt (Red Hat)1-2/+0
The creation of tracing files and directories is for the most part encapsulated in helper functions in trace.c. Other files do not need to include debugfs.h or fs.h, as they may have needed to in the past. Remove them from the files that do not need them. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-04-30tracing: Remove mock up poll wait functionSteven Rostedt (Red Hat)1-1/+0
Now that the ring buffer has a built in way to wake up readers when there's data, using irq_work such that it is safe to do it in any context. But it was still using the old "poor man's" wait polling that checks every 1/10 of a second to see if it should wake up a waiter. This makes the latency for a wake up excruciatingly long. No need to do that anymore. Completely remove the different wait_poll types from the tracers and have them all use the default one now. Reported-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-02-20tracing: Set up infrastructure to allow tracers for instancesSteven Rostedt (Red Hat)1-1/+2
Currently the tracers (function, function_graph, irqsoff, etc) can only be used by the top level tracing directory (not for instances). This sets up the infrastructure to allow instances to be able to run a separate tracer apart from the what the top level tracing is doing. As tracers need to adapt for being used by instances, the tracers must flag if they can be used by instances or not. Currently only the 'nop' tracer can be used by all instances. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-02-20tracing: Pass trace_array to set_flag callbackSteven Rostedt (Red Hat)1-1/+1
As options (flags) may affect instances instead of being global the set_flag() callbacks need to receive the trace_array descriptor of the instance they will be modifying. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-03-23tracing/ftrace: make nop-tracer use polling wait for events on pipeFrederic Weisbecker1-0/+1
Impact: display events when they arrive Now that the events don't use wake_up() anymore, we need the nop tracer to poll waiting for events on the pipe. Especially because nop is useful to look at orphan traces types (traces types that don't rely on specific tracers) because it doesn't produce traces itself. And unlike other tracers that trigger specific traces periodically, nop triggers no traces by itself that can wake him. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1237759847-21025-5-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-06trace: Call tracing_reset_online_cpus before tracer->init()Arnaldo Carvalho de Melo1-1/+0
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>
2009-01-29trace: Use tracing_reset_online_cpus in more placesArnaldo Carvalho de Melo1-5/+1
Impact: cleanup 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>
2008-11-18tracing/ftrace: make nop tracer using tracer flagsFrederic Weisbecker1-0/+52
Impact: give an example on how to use specific tracer flags This patch propose to use the nop tracer to provide an example for using the tracer's custom flags implementation. V2: replace structures and defines just after the headers includes for cleanliness. V3: replace defines by enum values. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Steven Noonan <steven@uplinklabs.net> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-16tracing/ftrace: change the type of the init() callbackFrederic Weisbecker1-1/+2
Impact: extend the ->init() method with the ability to fail This bring a way to know if the initialization of a tracer successed. A tracer must return 0 on success and a traditional error (ie: -ENOMEM) if it fails. If a tracer fails to init, it is free to print a detailed warn. The tracing api will not and switch to a new tracer will just return the error from the init callback. Note: this will be used for the return tracer. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-08ftrace: remove trace array ctrlSteven Rostedt1-4/+2
Impact: remove obsolete variable in trace_array structure With the new start / stop method of ftrace, the ctrl variable in the trace_array structure is now obsolete. Remove it. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-08ftrace: remove ctrl_update methodSteven Rostedt1-10/+0
Impact: Remove the ctrl_update tracer method With the new quick start/stop method of tracing, the ctrl_update method is out of date. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-14ftrace: make work with new ring bufferSteven Rostedt1-1/+1
This patch ports ftrace over to the new ring buffer. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-14tracing/ftrace: replace none tracer by nop tracerFrédéric Weisbecker1-6/+1
Replace "none" tracer by the recently created "nop" tracer. Both are pretty similar except that nop accepts TRACE_PRINT or TRACE_SPECIAL entries. And as a consequence, changing the size of the ring buffer now requires that tracing has already been disabled. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Steven Noonan <steven@uplinklabs.net> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-14tracing/ftrace: make nop tracer reset previous entriesFrédéric Weisbecker1-0/+4
If nop tracer is selected, some old entries from the previous tracer could still be enqueued. Tracing have to be reset. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Steven Noonan <steven@uplinklabs.net> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-14ftrace: add nop tracerSteven Noonan1-0/+65
A no-op tracer which can serve two purposes: 1. A template for development of a new tracer. 2. A convenient way to see ftrace_printk() calls without an irrelevant trace making the output messy. [ mingo@elte.hu: resolved conflicts ] Signed-off-by: Steven Noonan <steven@uplinklabs.net> Signed-off-by: Ingo Molnar <mingo@elte.hu>