path: root/lib
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authorLivio Soares <livio@eecg.toronto.edu>2007-12-18 15:21:13 +0100
committerIngo Molnar <mingo@elte.hu>2007-12-18 15:21:13 +0100
commitc7af77b584b02d3e321b00203a618a9c93782121 (patch)
treee7a8d5995e34065aa1bd610cb92684c5e5856119 /lib
parentsched: fix crash on ia64, introduce task_current() (diff)
sched: mark rwsem functions as __sched for wchan/profiling
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>
Diffstat (limited to 'lib')
1 files changed, 1 insertions, 1 deletions
diff --git a/lib/rwsem.c b/lib/rwsem.c
index cdb4e3d05607..7d02700a4b0e 100644
--- a/lib/rwsem.c
+++ b/lib/rwsem.c
@@ -146,7 +146,7 @@ __rwsem_do_wake(struct rw_semaphore *sem, int downgrading)
* wait for a lock to be granted
-static struct rw_semaphore *
+static struct rw_semaphore __sched *
rwsem_down_failed_common(struct rw_semaphore *sem,
struct rwsem_waiter *waiter, signed long adjustment)