Commit-ID: 63b1a81699c2a45c9f737419b1ec1da0ecf92812 Gitweb: http://git.kernel.org/tip/63b1a81699c2a45c9f737419b1ec1da0ecf92812 Author: Heiko Carstens <heiko.carst...@de.ibm.com> AuthorDate: Thu, 16 Jan 2014 14:54:50 +0100 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Thu, 16 Jan 2014 15:14:32 +0100
futexes: Fix futex_hashsize initialization "futexes: Increase hash table size for better performance" introduces a new alloc_large_system_hash() call. alloc_large_system_hash() however may allocate less memory than requested, e.g. limited by MAX_ORDER. Hence pass a pointer to alloc_large_system_hash() which will contain the hash shift when the function returns. Afterwards correctly set futex_hashsize. Fixes a crash on s390 where the requested allocation size was 4MB but only 1MB was allocated. Signed-off-by: Heiko Carstens <heiko.carst...@de.ibm.com> Cc: Darren Hart <dvh...@linux.intel.com> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Paul E. McKenney <paul...@linux.vnet.ibm.com> Cc: Waiman Long <waiman.l...@hp.com> Cc: Jason Low <jason.l...@hp.com> Cc: Davidlohr Bueso <davidl...@hp.com> Link: http://lkml.kernel.org/r/20140116135450.GA4345@osiris Signed-off-by: Ingo Molnar <mi...@kernel.org> --- kernel/futex.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/kernel/futex.c b/kernel/futex.c index 30971b5..1ddc449 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -2844,6 +2844,7 @@ SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val, static int __init futex_init(void) { u32 curval; + unsigned int futex_shift; unsigned long i; #if CONFIG_BASE_SMALL @@ -2855,8 +2856,9 @@ static int __init futex_init(void) futex_queues = alloc_large_system_hash("futex", sizeof(*futex_queues), futex_hashsize, 0, futex_hashsize < 256 ? HASH_SMALL : 0, - NULL, NULL, futex_hashsize, futex_hashsize); - + &futex_shift, NULL, + futex_hashsize, futex_hashsize); + futex_hashsize = 1UL << futex_shift; /* * This will fail and we want it. Some arch implementations do * runtime detection of the futex_atomic_cmpxchg_inatomic() -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
