mirror of
https://github.com/team-infusion-developers/android_kernel_samsung_msm8976.git
synced 2024-11-07 04:09:21 +00:00
c644f0e4b5
As suggested by Andreas Dilger, introduce a bgl_lock_ptr() helper in <linux/blockgroup_lock.h> and add separate sb_bgl_lock() helpers to filesystem specific header files to break the hidden dependency to struct ext[234]_sb_info. Also, while at it, convert the macros to static inlines to try make up for all the times I broke Andrew Morton's tree. Acked-by: Andreas Dilger <adilger@sun.com> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> Cc: <linux-ext4@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
62 lines
1.1 KiB
C
62 lines
1.1 KiB
C
#ifndef _LINUX_BLOCKGROUP_LOCK_H
|
|
#define _LINUX_BLOCKGROUP_LOCK_H
|
|
/*
|
|
* Per-blockgroup locking for ext2 and ext3.
|
|
*
|
|
* Simple hashed spinlocking.
|
|
*/
|
|
|
|
#include <linux/spinlock.h>
|
|
#include <linux/cache.h>
|
|
|
|
#ifdef CONFIG_SMP
|
|
|
|
/*
|
|
* We want a power-of-two. Is there a better way than this?
|
|
*/
|
|
|
|
#if NR_CPUS >= 32
|
|
#define NR_BG_LOCKS 128
|
|
#elif NR_CPUS >= 16
|
|
#define NR_BG_LOCKS 64
|
|
#elif NR_CPUS >= 8
|
|
#define NR_BG_LOCKS 32
|
|
#elif NR_CPUS >= 4
|
|
#define NR_BG_LOCKS 16
|
|
#elif NR_CPUS >= 2
|
|
#define NR_BG_LOCKS 8
|
|
#else
|
|
#define NR_BG_LOCKS 4
|
|
#endif
|
|
|
|
#else /* CONFIG_SMP */
|
|
#define NR_BG_LOCKS 1
|
|
#endif /* CONFIG_SMP */
|
|
|
|
struct bgl_lock {
|
|
spinlock_t lock;
|
|
} ____cacheline_aligned_in_smp;
|
|
|
|
struct blockgroup_lock {
|
|
struct bgl_lock locks[NR_BG_LOCKS];
|
|
};
|
|
|
|
static inline void bgl_lock_init(struct blockgroup_lock *bgl)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < NR_BG_LOCKS; i++)
|
|
spin_lock_init(&bgl->locks[i].lock);
|
|
}
|
|
|
|
/*
|
|
* The accessor is a macro so we can embed a blockgroup_lock into different
|
|
* superblock types
|
|
*/
|
|
static inline spinlock_t *
|
|
bgl_lock_ptr(struct blockgroup_lock *bgl, unsigned int block_group)
|
|
{
|
|
return &bgl->locks[(block_group) & (NR_BG_LOCKS-1)].lock;
|
|
}
|
|
|
|
#endif
|