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path: root/drivers/oprofile/event_buffer.c
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2011-09-13locking, oprofile: Annotate oprofilefs lock as rawThomas Gleixner1-2/+2
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 <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-07-26oprofile: make event buffer nonseekableArnd Bergmann1-1/+2
The event buffer cannot deal with seeks, so we should forbid that outright. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Robert Richter <robert.richter@amd.com> Cc: oprofile-list@lists.sf.net Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-10-09oprofile: warn on freeing event buffer too earlyRobert Richter1-10/+15
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 <rientjes@google.com> Cc: Stephane Eranian <eranian@google.com> Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-10-09oprofile: fix race condition in event_buffer freeDavid Rientjes1-1/+13
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 <rientjes@google.com> Signed-off-by: Stephane Eranian <eranian@google.com> Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-12-16oprofile: rename kernel-wide identifiersRobert Richter1-2/+2
This patch renames kernel-wide identifiers to something more oprofile specific names. Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-10-27oprofile: fix memory orderingNick Piggin1-3/+3
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 <npiggin@suse.de> Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-10-16oprofile: fixing whitespaces in drivers/oprofile/*Robert Richter1-12/+12
Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-10-15oprofile: more whitespace fixesRobert Richter1-5/+5
Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-08-26powerpc/cell/oprofile: Avoid double vfree of profile bufferCarl Love1-0/+2
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 <carll@us.ibm.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Robert Richter <robert.richter@amd.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-03-28[PATCH] oprofile: fix potential deadlock on oprofilefs_lockJiri Kosina1-2/+3
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 <jkosina@suse.cz> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12[PATCH] mark struct file_operations const 5Arjan van de Ven1-1/+1
Many struct file_operations in the kernel can be "const". Marking them const moves these to the .rodata section, which avoids false sharing with potential dirty data. In addition it'll catch accidental writes at compile time to these shared resources. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2006-06-25[PATCH] oprofile: convert from semaphores to mutexesMarkus Armbruster1-6/+6
Signed-off-by: Markus Armbruster <armbru@redhat.com> Cc: Philippe Elie <phil.el@wanadoo.fr> Cc: John Levon <levon@movementarian.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-11[PATCH] move capable() to capability.hRandy.Dunlap1-0/+1
- Move capable() from sched.h to capability.h; - Use <linux/capability.h> where capable() is used (in include/, block/, ipc/, kernel/, a few drivers/, mm/, security/, & sound/; many more drivers/ to go) Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16Linux-2.6.12-rc2Linus Torvalds1-0/+187
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!
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