Searched hist:"2 a4419b5b2a77f3f4537c14f7ad7df95770655dd" (Results 1 – 4 of 4) sorted by relevance
| /openbmc/linux/fs/ |
| H A D | fs_struct.c | diff 2a4419b5b2a77f3f4537c14f7ad7df95770655dd Tue Aug 17 13:37:33 CDT 2010 Nick Piggin <npiggin@kernel.dk> fs: fs_struct rwlock to spinlock
fs: fs_struct rwlock to spinlock
struct fs_struct.lock is an rwlock with the read-side used to protect root and
pwd members while taking references to them. Taking a reference to a path
typically requires just 2 atomic ops, so the critical section is very small.
Parallel read-side operations would have cacheline contention on the lock, the
dentry, and the vfsmount cachelines, so the rwlock is unlikely to ever give a
real parallelism increase.
Replace it with a spinlock to avoid one or two atomic operations in typical
path lookup fastpath.
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
| H A D | exec.c | diff 2a4419b5b2a77f3f4537c14f7ad7df95770655dd Tue Aug 17 13:37:33 CDT 2010 Nick Piggin <npiggin@kernel.dk> fs: fs_struct rwlock to spinlock
fs: fs_struct rwlock to spinlock
struct fs_struct.lock is an rwlock with the read-side used to protect root and
pwd members while taking references to them. Taking a reference to a path
typically requires just 2 atomic ops, so the critical section is very small.
Parallel read-side operations would have cacheline contention on the lock, the
dentry, and the vfsmount cachelines, so the rwlock is unlikely to ever give a
real parallelism increase.
Replace it with a spinlock to avoid one or two atomic operations in typical
path lookup fastpath.
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
| /openbmc/linux/include/linux/ |
| H A D | fs_struct.h | diff 2a4419b5b2a77f3f4537c14f7ad7df95770655dd Tue Aug 17 13:37:33 CDT 2010 Nick Piggin <npiggin@kernel.dk> fs: fs_struct rwlock to spinlock
fs: fs_struct rwlock to spinlock
struct fs_struct.lock is an rwlock with the read-side used to protect root and
pwd members while taking references to them. Taking a reference to a path
typically requires just 2 atomic ops, so the critical section is very small.
Parallel read-side operations would have cacheline contention on the lock, the
dentry, and the vfsmount cachelines, so the rwlock is unlikely to ever give a
real parallelism increase.
Replace it with a spinlock to avoid one or two atomic operations in typical
path lookup fastpath.
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
| /openbmc/linux/kernel/ |
| H A D | fork.c | diff 2a4419b5b2a77f3f4537c14f7ad7df95770655dd Tue Aug 17 13:37:33 CDT 2010 Nick Piggin <npiggin@kernel.dk> fs: fs_struct rwlock to spinlock
fs: fs_struct rwlock to spinlock
struct fs_struct.lock is an rwlock with the read-side used to protect root and
pwd members while taking references to them. Taking a reference to a path
typically requires just 2 atomic ops, so the critical section is very small.
Parallel read-side operations would have cacheline contention on the lock, the
dentry, and the vfsmount cachelines, so the rwlock is unlikely to ever give a
real parallelism increase.
Replace it with a spinlock to avoid one or two atomic operations in typical
path lookup fastpath.
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|