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author | 2015-08-04 12:17:53 -0700 | |
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committer | 2015-08-04 15:44:42 -0700 | |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/include/linux/blockgroup_lock.h | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/include/linux/blockgroup_lock.h')
-rw-r--r-- | kernel/include/linux/blockgroup_lock.h | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/kernel/include/linux/blockgroup_lock.h b/kernel/include/linux/blockgroup_lock.h new file mode 100644 index 000000000..e44b88ba5 --- /dev/null +++ b/kernel/include/linux/blockgroup_lock.h @@ -0,0 +1,62 @@ +#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 |