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* sched: mark rwsem functions as __sched for wchan/profilingLivio Soares2007-12-181-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | This following commit http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=fdf8cb0909b531f9ae8f9b9d7e4eb35ba3505f07 un-inlined a low-level rwsem function, but did not mark it as __sched. The result is that it now shows up as thread wchan (which also affects /proc/profile stats). The following simple patch fixes this by properly marking rwsem_down_failed_common() as a __sched function. Also in this patch, which is up for discussion, marks down_read() and down_write() proper as __sched. For profiling, it is pretty much useless to know that a semaphore is beig help - it is necessary to know _which_ one. By going up another frame on the stack, the information becomes much more useful. In summary, the below change to lib/rwsem.c should be applied; the changes to kernel/rwsem.c could be applied if other kernel hackers agree with my proposal that down_read()/down_write() in the profile is not enough. [ akpm@linux-foundation.org: build fix ] Signed-off-by: Livio Soares <livio@eecg.toronto.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* lockstat: hook into spinlock_t, rwlock_t, rwsem and mutexPeter Zijlstra2007-07-191-4/+4
| | | | | | | | | | Call the new lockstat tracking functions from the various lock primitives. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Lockdep treats down_write_trylock like regular down_writePavel Emelianov2007-05-081-1/+1
| | | | | | | | | | | | | | | | | | | | | This causes constructions like down_write(&mm1->mmap_sem); if (down_write_trylock(&mm2->mmap_sem)) { ... up_write(&mm2->mmap_sem); } up_write(&mm1->mmap_sem); generate a lockdep warning about circular locking dependence. Call rwsem_acquire() with trylock set to 1. Cc: Ingo Molnar <mingo@elte.hu> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] lockdep: prove rwsem locking correctnessIngo Molnar2006-07-041-0/+42
| | | | | | | | | Use the lock validator framework to prove rwsem locking correctness. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] lockdep: clean up rwsemsIngo Molnar2006-07-041-0/+105
Clean up rwsems. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>