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mtx: change MTX_UNOWNED from 4 to 0

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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:
Mateusz Guzik 2017-10-13 20:31:56 +00:00
parent 96842052d3
commit 30a33cefae
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=324609
1 changed files with 3 additions and 7 deletions
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10
sys/sys/mutex.h
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@ -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