rtla: Fix segfault in save_trace_to_file call

Running rtla with exit on threshold, but without saving trace leads to a
segmenetation fault:

$ rtla timerlat hist -T 10
...
Max timerlat IRQ latency f

rtla: Fix segfault in save_trace_to_file call

Running rtla with exit on threshold, but without saving trace leads to a
segmenetation fault:

$ rtla timerlat hist -T 10
...
Max timerlat IRQ latency from idle: 4.29 us in cpu 0
Segmentation fault

This is caused by null pointer deference in the call of
save_trace_to_file, which attempts to dereference an uninitialized
osnoise_tool variable:

save_trace_to_file(record->trace.inst, params->trace_output);
^ this is uninitialized if params->trace_output is
not set

Fix this by not attempting to dereference "record" if it is NULL and
passing NULL instead. As a safety measure, the first field is also
checked for NULL inside save_trace_to_file.

Cc: John Kacur <[email protected]>
Cc: Luis Goncalves <[email protected]>
Cc: Costa Shulyupin <[email protected]>
Link: https://lore.kernel.org/[email protected]
Fixes: dc4d4e7c72d1 ("rtla: Refactor save_trace_to_file")
Signed-off-by: Tomas Glozar <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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rtla: Refactor save_trace_to_file

The functions osnoise_hist_main(), osnoise_top_main(),
timerlat_hist_main(), and timerlat_top_main() are lengthy and contain
duplicated code.

Refactor by consolida

rtla: Refactor save_trace_to_file

The functions osnoise_hist_main(), osnoise_top_main(),
timerlat_hist_main(), and timerlat_top_main() are lengthy and contain
duplicated code.

Refactor by consolidating the duplicate lines into the
save_trace_to_file() function.

Cc: Daniel Bristot de Oliveira <[email protected]>
Cc: John Kacur <[email protected]>
Cc: "Luis Claudio R. Goncalves" <[email protected]>
Cc: Eder Zulian <[email protected]>
Cc: Dan Carpenter <[email protected]>
Cc: Gabriele Monaco <[email protected]>
Link: https://lore.kernel.org/[email protected]
Signed-off-by: Costa Shulyupin <[email protected]>
Reviewed-by: Tomas Glozar <[email protected]>
Tested-by: Tomas Glozar <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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rtla: Count all processed events

Add a field processed_events to struct trace_instance and increment it
in collect_registered_events, regardless of whether a handler is
registered for the event.

Th

rtla: Count all processed events

Add a field processed_events to struct trace_instance and increment it
in collect_registered_events, regardless of whether a handler is
registered for the event.

The purpose is to calculate the percentage of events that were missed
due to tracefs buffer overflow.

Cc: John Kacur <[email protected]>
Cc: Luis Goncalves <[email protected]>
Cc: Gabriele Monaco <[email protected]>
Link: https://lore.kernel.org/[email protected]
Signed-off-by: Tomas Glozar <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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rtla: Count missed trace events

Add function collect_missed_events to trace.c to act as a callback for
tracefs_follow_missed_events, summing the number of total missed events
into a new field missin

rtla: Count missed trace events

Add function collect_missed_events to trace.c to act as a callback for
tracefs_follow_missed_events, summing the number of total missed events
into a new field missing_events of struct trace_instance.

In case record->missed_events is negative, trace->missed_events is set
to UINT64_MAX to signify an unknown number of events was missed.

The callback is activated on initialization of the trace instance.

Cc: John Kacur <[email protected]>
Cc: Luis Goncalves <[email protected]>
Cc: Gabriele Monaco <[email protected]>
Link: https://lore.kernel.org/[email protected]
Signed-off-by: Tomas Glozar <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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tools/rtla: Add osnoise_trace_is_off()

All of the users of trace_is_off() passes in &record->trace as the second
parameter, where record is a pointer to a struct osnoise_tool. This record
could be N

tools/rtla: Add osnoise_trace_is_off()

All of the users of trace_is_off() passes in &record->trace as the second
parameter, where record is a pointer to a struct osnoise_tool. This record
could be NULL and there is a hidden dependency that the trace field is the
first field to allow &record->trace to work with a NULL record pointer.

In order to make this code a bit more robust, as record shouldn't be
dereferenced if it is NULL, even if the code does work, create a new
function called osnoise_trace_is_off() that takes the pointer to a
struct osnoise_tool as its second parameter. This way it can properly test
if it is NULL before it dereferences it.

The old function trace_is_off() is removed and the function
osnoise_trace_is_off() is added into osnoise.c which is what the
struct osnoise_tool is associated with.

Cc: John Kacur <[email protected]>
Cc: "Luis Claudio R. Goncalves" <[email protected]>
Cc: Eder Zulian <[email protected]>
Cc: Dan Carpenter <[email protected]>
Cc: Tomas Glozar <[email protected]>
Cc: Gabriele Monaco <[email protected]>
Link: https://lore.kernel.org/[email protected]
Signed-off-by: Costa Shulyupin <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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rtla: Add trace_instance_stop

Support not only turning trace on for the timerlat tracer, but also
turning it off.

This will be used in subsequent patches to stop the timerlat tracer
without also wi

rtla: Add trace_instance_stop

Support not only turning trace on for the timerlat tracer, but also
turning it off.

This will be used in subsequent patches to stop the timerlat tracer
without also wiping the trace buffer.

Cc: [email protected]
Cc: John Kacur <[email protected]>
Cc: Luis Goncalves <[email protected]>
Cc: Gabriele Monaco <[email protected]>
Link: https://lore.kernel.org/[email protected]
Signed-off-by: Tomas Glozar <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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rtla: Add --trace-buffer-size option

Add the option allow the users to set a different buffer size for the
trace. For example, in large systems, the user might be interested on
reducing the trace bu

rtla: Add --trace-buffer-size option

Add the option allow the users to set a different buffer size for the
trace. For example, in large systems, the user might be interested on
reducing the trace buffer to avoid large tracing files.

The buffer size is specified in kB, and it is only affecting
the tracing instance.

The function trace_set_buffer_size() appears on libtracefs v1.6,
so increase the minimum required version on Makefile.config.

Link: https://lkml.kernel.org/r/e7c9ca5b3865f28e131a49ec3b984fadf2d056c6.1715860611.git.bristot@kernel.org

Cc: Jonathan Corbet <[email protected]>
Cc: Juri Lelli <[email protected]>
Cc: John Kacur <[email protected]>
Signed-off-by: Daniel Bristot de Oliveira <[email protected]>

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rtla: Fix double free

Avoid double free by making trace_instance_destroy indempotent. When
trace_instance_init fails, it calls trace_instance_destroy, but its only
caller osnoise_destroy_tool calls

rtla: Fix double free

Avoid double free by making trace_instance_destroy indempotent. When
trace_instance_init fails, it calls trace_instance_destroy, but its only
caller osnoise_destroy_tool calls it again.

Link: https://lkml.kernel.org/r/[email protected]

Fixes: 0605bf009f18 ("rtla: Add osnoise tool")
Signed-off-by: Andreas Schwab <[email protected]>
Acked-by: Daniel Bristot de Oliveira <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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rtla: Check for trace off also in the trace instance

With the addition of --trigger option, it is also possible to stop
the trace from the -t tracing instance using the traceoff trigger.

Make rtla

rtla: Check for trace off also in the trace instance

With the addition of --trigger option, it is also possible to stop
the trace from the -t tracing instance using the traceoff trigger.

Make rtla tools to check if the trace is stopped also in the trace
instance, stopping the execution of the tool.

Link: https://lkml.kernel.org/r/59fc7c6f23dddd5c8b7ef1782cf3da51ea2ce0f5.1646247211.git.bristot@kernel.org

Cc: Daniel Bristot de Oliveira <[email protected]>
Cc: Clark Williams <[email protected]>
Cc: Juri Lelli <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Signed-off-by: Daniel Bristot de Oliveira <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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rtla/trace: Save event histogram output to a file

The hist: trigger generates a histogram in the file sys/event/hist.
If the hist: trigger is used, automatically save the histogram output of
the eve

rtla/trace: Save event histogram output to a file

The hist: trigger generates a histogram in the file sys/event/hist.
If the hist: trigger is used, automatically save the histogram output of
the event sys:event in the sys_event_hist.txt file.

Link: https://lkml.kernel.org/r/b5c906af31d4e022ffe87fb0848fac5c089087c8.1646247211.git.bristot@kernel.org

Cc: Daniel Bristot de Oliveira <[email protected]>
Cc: Clark Williams <[email protected]>
Cc: Juri Lelli <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Signed-off-by: Daniel Bristot de Oliveira <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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rtla/trace: Add trace event filter helpers

Add a set of helper functions to allow rtla tools to filter events
in the trace instance.

Link: https://lkml.kernel.org/r/12623b1684684549d53b90f4bf66fae4

rtla/trace: Add trace event filter helpers

Add a set of helper functions to allow rtla tools to filter events
in the trace instance.

Link: https://lkml.kernel.org/r/12623b1684684549d53b90f4bf66fae44584fd14.1646247211.git.bristot@kernel.org

Cc: Daniel Bristot de Oliveira <[email protected]>
Cc: Clark Williams <[email protected]>
Cc: Juri Lelli <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Signed-off-by: Daniel Bristot de Oliveira <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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rtla/trace: Add trace event trigger helpers

Add a set of helper functions to allow rtla tools to trigger event
actions in the trace instance.

Link: https://lkml.kernel.org/r/e0d31abe879a78a5600b64f

rtla/trace: Add trace event trigger helpers

Add a set of helper functions to allow rtla tools to trigger event
actions in the trace instance.

Link: https://lkml.kernel.org/r/e0d31abe879a78a5600b64f904d0dfa8f76e4fbb.1646247211.git.bristot@kernel.org

Cc: Daniel Bristot de Oliveira <[email protected]>
Cc: Clark Williams <[email protected]>
Cc: Juri Lelli <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Signed-off-by: Daniel Bristot de Oliveira <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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rtla/trace: Add trace events helpers

Add a set of helper functions to allow the rtla tools to enable
additional tracepoints in the trace instance.

Link: https://lkml.kernel.org/r/932398b36c1bbaa22c

rtla/trace: Add trace events helpers

Add a set of helper functions to allow the rtla tools to enable
additional tracepoints in the trace instance.

Link: https://lkml.kernel.org/r/932398b36c1bbaa22c7810d7a40ca9b8c5595b94.1646247211.git.bristot@kernel.org

Cc: Daniel Bristot de Oliveira <[email protected]>
Cc: Clark Williams <[email protected]>
Cc: Juri Lelli <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Signed-off-by: Daniel Bristot de Oliveira <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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rtla/trace: Error message fixup

Use capital and change "tracer %s" to "%s tracer".

No functional change.

Link: https://lkml.kernel.org/r/361697d27431afefa64c67c323564205385c418d.1643990447.git.bri

rtla/trace: Error message fixup

Use capital and change "tracer %s" to "%s tracer".

No functional change.

Link: https://lkml.kernel.org/r/361697d27431afefa64c67c323564205385c418d.1643990447.git.bristot@kernel.org

Fixes: b1696371d865 ("rtla: Helper functions for rtla")
Cc: Daniel Bristot de Oliveira <[email protected]>
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Daniel Bristot de Oliveira <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

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rtla: Helper functions for rtla

This is a set of utils and tracer helper functions. They are used by
rtla mostly to parse config, display data and some trace operations that
are not part of libtrace

rtla: Helper functions for rtla

This is a set of utils and tracer helper functions. They are used by
rtla mostly to parse config, display data and some trace operations that
are not part of libtracefs (because they are only useful it for this
case).

Link: https://lkml.kernel.org/r/a94c128aba9e6e66d502b7094f2e8c7ac95b12e5.1639158831.git.bristot@kernel.org

Cc: Tao Zhou <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Tom Zanussi <[email protected]>
Cc: Masami Hiramatsu <[email protected]>
Cc: Juri Lelli <[email protected]>
Cc: Clark Williams <[email protected]>
Cc: John Kacur <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Sebastian Andrzej Siewior <[email protected]>
Cc: Daniel Bristot de Oliveira <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Daniel Bristot de Oliveira <[email protected]>
Signed-off-by: Steven Rostedt <[email protected]>

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