From 4f89849da22db9d0edb378acea65e23fcd546173 Mon Sep 17 00:00:00 2001 From: Minchan Kim Date: Tue, 30 Apr 2013 15:26:54 -0700 Subject: frontswap: get rid of swap_lock dependency Frontswap initialization routine depends on swap_lock, which want to be atomic about frontswap's first appearance. IOW, frontswap is not present and will fail all calls OR frontswap is fully functional but if new swap_info_struct isn't registered by enable_swap_info, swap subsystem doesn't start I/O so there is no race between init procedure and page I/O working on frontswap. So let's remove unnecessary swap_lock dependency. Cc: Dan Magenheimer Signed-off-by: Minchan Kim [v1: Rebased on my branch, reworked to work with backends loading late] [v2: Added a check for !map] [v3: Made the invalidate path follow the init path] [v4: Address comments by Wanpeng Li ] Signed-off-by: Konrad Rzeszutek Wilk Signed-off-by: Bob Liu Cc: Wanpeng Li Cc: Andor Daam Cc: Florian Schmaus Cc: Stefan Hengelein Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/frontswap.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'include/linux/frontswap.h') diff --git a/include/linux/frontswap.h b/include/linux/frontswap.h index 6c49e1eba552..8293262401de 100644 --- a/include/linux/frontswap.h +++ b/include/linux/frontswap.h @@ -23,7 +23,7 @@ extern void frontswap_writethrough(bool); extern void frontswap_tmem_exclusive_gets(bool); extern bool __frontswap_test(struct swap_info_struct *, pgoff_t); -extern void __frontswap_init(unsigned type); +extern void __frontswap_init(unsigned type, unsigned long *map); extern int __frontswap_store(struct page *page); extern int __frontswap_load(struct page *page); extern void __frontswap_invalidate_page(unsigned, pgoff_t); @@ -98,10 +98,10 @@ static inline void frontswap_invalidate_area(unsigned type) __frontswap_invalidate_area(type); } -static inline void frontswap_init(unsigned type) +static inline void frontswap_init(unsigned type, unsigned long *map) { if (frontswap_enabled) - __frontswap_init(type); + __frontswap_init(type, map); } #endif /* _LINUX_FRONTSWAP_H */ -- cgit