diff options
| author | Tim Chen <tim.c.chen@linux.intel.com> | 2017-02-22 15:45:33 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-02-22 16:41:30 -0800 |
| commit | 36005bae205da3eef0016a5c96a34f10a68afa1e (patch) | |
| tree | b3201463a223eb7ec4a0bcf960696db21914566d /include/linux/swap.h | |
| parent | e8c26ab60598558ec3a626e7925b06e7417d7710 (diff) | |
mm/swap: allocate swap slots in batches
Currently, the swap slots are allocated one page at a time, causing
contention to the swap_info lock protecting the swap partition on every
page being swapped.
This patch adds new functions get_swap_pages and scan_swap_map_slots to
request multiple swap slots at once. This will reduces the lock
contention on the swap_info lock. Also scan_swap_map_slots can operate
more efficiently as swap slots often occurs in clusters close to each
other on a swap device and it is quicker to allocate them together.
Link: http://lkml.kernel.org/r/9fec2845544371f62c3763d43510045e33d286a6.1484082593.git.tim.c.chen@linux.intel.com
Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Cc: Aaron Lu <aaron.lu@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net> escreveu:
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Shaohua Li <shli@kernel.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/linux/swap.h')
| -rw-r--r-- | include/linux/swap.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/include/linux/swap.h b/include/linux/swap.h index 3116382067cd..956eae8a8edf 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -27,6 +27,7 @@ struct bio; #define SWAP_FLAGS_VALID (SWAP_FLAG_PRIO_MASK | SWAP_FLAG_PREFER | \ SWAP_FLAG_DISCARD | SWAP_FLAG_DISCARD_ONCE | \ SWAP_FLAG_DISCARD_PAGES) +#define SWAP_BATCH 64 static inline int current_is_kswapd(void) { @@ -386,6 +387,7 @@ static inline long get_nr_swap_pages(void) extern void si_swapinfo(struct sysinfo *); extern swp_entry_t get_swap_page(void); extern swp_entry_t get_swap_page_of_type(int); +extern int get_swap_pages(int n, swp_entry_t swp_entries[]); extern int add_swap_count_continuation(swp_entry_t, gfp_t); extern void swap_shmem_alloc(swp_entry_t); extern int swap_duplicate(swp_entry_t); |