d/freebsd-skq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

mtx: change MTX_UNOWNED from 4 to 0

Browse Source 
The value is spread all over the kernel and zeroing a register is
cheaper/shorter than setting it up to an arbitrary value.

Reduces amd64 GENERIC-NODEBUG .text size by 0.4%.

MFC after:	1 week
This commit is contained in:
mjg 2017-10-13 20:31:56 +00:00
parent 0e88e8ddf5
commit 2658fd615e
1 changed files with 3 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
sys/sys/mutex.h
View File

@ -65,15 +65,11 @@
* State bits kept in mutex->mtx_lock, for the DEFAULT lock type. None of this,
* with the exception of MTX_UNOWNED, applies to spin locks.
*/
#define MTX_UNOWNED 0x00000000 /* Cookie for free mutex */
#define MTX_RECURSED 0x00000001 /* lock recursed (for MTX_DEF only) */
#define MTX_CONTESTED 0x00000002 /* lock contested (for MTX_DEF only) */
#define MTX_UNOWNED 0x00000004 /* Cookie for free mutex */
#define MTX_FLAGMASK (MTX_RECURSED | MTX_CONTESTED | MTX_UNOWNED)
/*
* Value stored in mutex->mtx_lock to denote a destroyed mutex.
*/
#define MTX_DESTROYED (MTX_CONTESTED | MTX_UNOWNED)
#define MTX_DESTROYED 0x00000004 /* lock destroyed */
#define MTX_FLAGMASK (MTX_RECURSED | MTX_CONTESTED | MTX_DESTROYED)
/*
* Prototypes