linux-toradex.git/drivers/oprofile/event_buffer.c, branch v3.10.42

locking, oprofile: Annotate oprofilefs lock as raw

2011-09-13T09:12:05+00:00

The oprofilefs_lock can be taken in atomic context (in profiling
interrupts) and therefore cannot cannot be preempted on -rt -
annotate it.

In mainline this change documents the low level nature of
the lock - otherwise there's no functional difference. Lockdep
and Sparse checking will work as usual.

Signed-off-by: Thomas Gleixner 
Signed-off-by: Ingo Molnar

oprofile: make event buffer nonseekable

2010-07-26T08:58:24+00:00

The event buffer cannot deal with seeks, so
we should forbid that outright.

Signed-off-by: Arnd Bergmann 
Cc: Robert Richter 
Cc: oprofile-list@lists.sf.net
Signed-off-by: Robert Richter

oprofile: warn on freeing event buffer too early

2009-10-09T19:32:05+00:00

A race shouldn't happen since all workqueues or handlers are canceled
or flushed before the event buffer is freed. A warning is triggered
now if the buffer is freed too early.

Also, this patch adds some comments about event buffer protection,
reworks some code and adds code to clear buffer_pos during alloc and
free of the event buffer.

Cc: David Rientjes 
Cc: Stephane Eranian 
Signed-off-by: Robert Richter

oprofile: fix race condition in event_buffer free

2009-10-09T16:02:01+00:00

Looking at the 2.6.31-rc9 code, it appears there is a race condition
in the event_buffer cleanup code path (shutdown). This could lead to
kernel panic as some CPUs may be operating on the event buffer AFTER
it has been freed. The attached patch solves the problem and makes
sure CPUs check if the buffer is not NULL before they access it as
some may have been spinning on the mutex while the buffer was being
freed.

The race may happen if the buffer is freed during pending reads. But
it is not clear why there are races in add_event_entry() since all
workqueues or handlers are canceled or flushed before the event buffer
is freed.

Signed-off-by: David Rientjes 
Signed-off-by: Stephane Eranian 
Signed-off-by: Robert Richter

oprofile: rename kernel-wide identifiers

2008-12-16T16:52:49+00:00

This patch renames kernel-wide identifiers to something more oprofile
specific names.

Cc: Andrew Morton 
Signed-off-by: Robert Richter

oprofile: fix memory ordering

2008-10-27T18:15:41+00:00

Regular bitops don't work as locks on all architectures.

Also: can use non-atomic unlock as no concurrent stores to the word.

Signed-off-by: Nick Piggin 
Signed-off-by: Robert Richter

oprofile: fixing whitespaces in drivers/oprofile/*

2008-10-16T13:01:40+00:00

Signed-off-by: Robert Richter

oprofile: more whitespace fixes

2008-10-15T18:55:51+00:00

Signed-off-by: Robert Richter

powerpc/cell/oprofile: Avoid double vfree of profile buffer

2008-08-26T00:24:46+00:00

If an error occurs on opcontrol start, the event and per cpu buffers
are released.  If later opcontrol shutdown is called then the free
function will be called again to free buffers that no longer
exist.  This results in a kernel oops.  The following changes
prevent the call to delete buffers that don't exist.

Signed-off-by: Carl Love 
Signed-off-by: Arnd Bergmann 
Acked-by: Robert Richter 
Signed-off-by: Paul Mackerras

[PATCH] oprofile: fix potential deadlock on oprofilefs_lock

2007-03-28T20:58:02+00:00

nmi_cpu_setup() is called from hardirq context and acquires oprofilefs_lock.
alloc_event_buffer() and oprofilefs_ulong_from_user() acquire this lock
without disabling irqs, which could deadlock.

Signed-off-by: Jiri Kosina 
Signed-off-by: Linus Torvalds