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| author | Anton Vorontsov <anton.vorontsov@linaro.org> | 2012-07-17 14:26:15 -0700 |
|---|---|---|
| committer | Anton Vorontsov <anton.vorontsov@linaro.org> | 2012-09-06 22:16:58 -0700 |
| commit | 65f8c95e46a1827ae8bbc52a817ea308dd7d65ae (patch) | |
| tree | adc856e8b50441b055350d8f1d83e3f641c77456 /fs/pstore/Kconfig | |
| parent | b4a871bce619dc5ca03cc6c78e1c467ceacb8e7e (diff) | |
| download | linux-65f8c95e46a1827ae8bbc52a817ea308dd7d65ae.tar.bz2 | |
pstore/ftrace: Convert to its own enable/disable debugfs knob
With this patch we no longer reuse function tracer infrastructure, now
we register our own tracer back-end via a debugfs knob.
It's a bit more code, but that is the only downside. On the bright side we
have:
- Ability to make persistent_ram module removable (when needed, we can
move ftrace_ops struct into a module). Note that persistent_ram is still
not removable for other reasons, but with this patch it's just one
thing less to worry about;
- Pstore part is more isolated from the generic function tracer. We tried
it already by registering our own tracer in available_tracers, but that
way we're loosing ability to see the traces while we record them to
pstore. This solution is somewhere in the middle: we only register
"internal ftracer" back-end, but not the "front-end";
- When there is only pstore tracing enabled, the kernel will only write
to the pstore buffer, omitting function tracer buffer (which, of course,
still can be enabled via 'echo function > current_tracer').
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Diffstat (limited to 'fs/pstore/Kconfig')
| -rw-r--r-- | fs/pstore/Kconfig | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/fs/pstore/Kconfig b/fs/pstore/Kconfig index d39bb5cce883..ca71db69da07 100644 --- a/fs/pstore/Kconfig +++ b/fs/pstore/Kconfig @@ -23,6 +23,7 @@ config PSTORE_FTRACE bool "Persistent function tracer" depends on PSTORE depends on FUNCTION_TRACER + depends on DEBUG_FS help With this option kernel traces function calls into a persistent ram buffer that can be decoded and dumped after reboot through |