Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 7c5f6b32 authored by Eric Biggers's avatar Eric Biggers Committed by Theodore Ts'o
Browse files

blockgroup_lock.h: simplify definition of NR_BG_LOCKS 



We can use ilog2() to more easily produce the desired NR_BG_LOCKS.  This
works because ilog2() is evaluated at compile-time when its argument is
a compile-time constant.

I did not change the chosen NR_BG_LOCKS values.

Signed-off-by: default avatarEric Biggers <ebiggers@google.com>
Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
Reviewed-by: default avatarAndreas Dilger <adilger@dilger.ca>
parent 9e5ab85d

include/linux/blockgroup_lock.h

+2 −20
Original line number Diff line number Diff line
@@ -10,28 +10,10 @@ 
#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

#define NR_BG_LOCKS	(4 << ilog2(NR_CPUS < 32 ? NR_CPUS : 32))

#else

#define NR_BG_LOCKS	4

#endif



#else	/* CONFIG_SMP */

#define NR_BG_LOCKS	1

#endif	/* CONFIG_SMP */

#endif



struct bgl_lock {

	spinlock_t lock;