diff options
| author | Davidlohr Bueso <[email protected]> | 2014-07-30 13:41:56 -0700 |
|---|---|---|
| committer | Ingo Molnar <[email protected]> | 2014-08-13 10:32:04 +0200 |
| commit | 0a7cbf9abe3198461de3d3e97268db32a646ba06 (patch) | |
| tree | 0e071f305840ba9aff93d16981963fa0cbcf09ba | |
| parent | 214e0aed639ef40987bf6159fad303171a6de31e (diff) | |
locking/Documentation: Update locking/mutex-design.txt disadvantages
Fortunately Jason was able to reduce some of the overhead we
had introduced in the original rwsem optimistic spinning -
an it is now the same size as mutexes. Update the documentation
accordingly.
Signed-off-by: Davidlohr Bueso <[email protected]>
Acked-by: Jason Low <[email protected]>
Signed-off-by: Peter Zijlstra <[email protected]>
Cc: [email protected]
Cc: Linus Torvalds <[email protected]>
Cc: Randy Dunlap <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
| -rw-r--r-- | Documentation/locking/mutex-design.txt | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/Documentation/locking/mutex-design.txt b/Documentation/locking/mutex-design.txt index ee231ed09ec6..60c482df1a38 100644 --- a/Documentation/locking/mutex-design.txt +++ b/Documentation/locking/mutex-design.txt @@ -145,9 +145,9 @@ Disadvantages Unlike its original design and purpose, 'struct mutex' is larger than most locks in the kernel. E.g: on x86-64 it is 40 bytes, almost twice -as large as 'struct semaphore' (24 bytes) and 8 bytes shy of the -'struct rw_semaphore' variant. Larger structure sizes mean more CPU -cache and memory footprint. +as large as 'struct semaphore' (24 bytes) and tied, along with rwsems, +for the largest lock in the kernel. Larger structure sizes mean more +CPU cache and memory footprint. When to use mutexes ------------------- |