This is a reworking of an original patch posted by Aaro Koskinen:
oprofile does not work with PM, because sysdev_suspend() is done with
interrupts disabled and oprofile needs a mutex. Implementing oprofile
as a platform device solves this problem.
Cc: Aaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Aaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
There are currently two hardware performance monitoring subsystems in
the kernel for ARM: OProfile and perf-events. This creates the
following problems:
1.) Duplicate PMU accessor code. Inevitable code drift may lead to
bugs in one framework that are fixed in the other.
2.) Locking issues. OProfile doesn't reprogram hardware counters
between profiling runs if the events to be monitored have not been
changed. This means that other profiling frameworks cannot use the
counters if OProfile is in use.
3.) Due to differences in the two frameworks, it may not be possible to
compare the results obtained by OProfile with those obtained by perf.
This patch removes the OProfile PMU driver code and replaces it with
calls to perf, therefore solving the issues mentioned above.
The only userspace-visible change is the lack of SCU counter support
for 11MPCore. This is currently unsupported by OProfile userspace tools anyway and therefore shouldn't cause any problems.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Jamie Iles <jamie.iles@picochip.com>
Cc: Jean Pihet <jpihet@mvista.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add Oprofile kernel support for ARMv7.
Tested on OMAP3430 and OMAP3530 chipsets (Cortex-A8).
Signed-off-by: Jean Pihet <jpihet@mvista.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
All kobjects require a dynamically allocated name now. We no longer
need to keep track if the name is statically assigned, we can just
unconditionally free() all kobject names on cleanup.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Always allow backtrace when using oprofile on ARM, even if a PMU
isn't present.
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add the glue for ARM11 SMP oprofile support, which also supports the
performance monitor in the coherency unit.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add oprofile glue for ARM11 (ARMv6) oprofile support. This
connects the ARM11 core profiling support to the oprofile code
for uniprocessor configurations.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
We need this to be zero initialised. Since this is an array, use kcalloc
rather than kzalloc or kmalloc.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Russ Dill
The oprofile init code was broken in commit c6b9da. The new logic will
always return -ENODEV. This fixes oprofile_arch_init to return 0 on
success, and return the return value of spec->init() if applicable.
Signed-off-by: Russ Dill <Russ.Dill@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
There is nothing special about having the init code separate from
the common code, so combine the two.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The common oprofile code assumes the name "PMU" (from Intel's
performance management unit). This is misleading when we
start adding oprofile support for other machine types which
don't use the same terminology. Call it op_arm_* instead of
pmu_*.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The oprofile suspend/resume was missing locking. If we failed
to start oprofile on resume, we still reported that it was
enabled. Instead, disable oprofile on error.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Will Deacon