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| author | Livio Soares <livio@eecg.toronto.edu> | 2007-12-18 15:21:13 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2007-12-18 15:21:13 +0100 |
| commit | c7af77b584b02d3e321b00203a618a9c93782121 (patch) | |
| tree | e7a8d5995e34065aa1bd610cb92684c5e5856119 | |
| parent | 051a1d1afa47206e23ae03f781c6795ce870e3d5 (diff) | |
| download | linux-c7af77b584b02d3e321b00203a618a9c93782121.tar.bz2 | |
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>
| -rw-r--r-- | kernel/rwsem.c | 5 | ||||
| -rw-r--r-- | lib/rwsem.c | 2 |
2 files changed, 4 insertions, 3 deletions
diff --git a/kernel/rwsem.c b/kernel/rwsem.c index 1ec620c03064..cae050b05f5e 100644 --- a/kernel/rwsem.c +++ b/kernel/rwsem.c @@ -6,6 +6,7 @@ #include <linux/types.h> #include <linux/kernel.h> +#include <linux/sched.h> #include <linux/module.h> #include <linux/rwsem.h> @@ -15,7 +16,7 @@ /* * lock for reading */ -void down_read(struct rw_semaphore *sem) +void __sched down_read(struct rw_semaphore *sem) { might_sleep(); rwsem_acquire_read(&sem->dep_map, 0, 0, _RET_IP_); @@ -42,7 +43,7 @@ EXPORT_SYMBOL(down_read_trylock); /* * lock for writing */ -void down_write(struct rw_semaphore *sem) +void __sched down_write(struct rw_semaphore *sem) { might_sleep(); rwsem_acquire(&sem->dep_map, 0, 0, _RET_IP_); 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) { |