path: root/mm/mincore.c
diff options
authorShaohua Li <shli@kernel.org>2013-02-22 16:34:37 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2013-02-23 17:50:17 -0800
commit33806f06da654092182410d974b6d3c5396ea3eb (patch)
tree7f7da99d94481a1d4c78ebf05b410fc8ba654a39 /mm/mincore.c
parent9800339b5e0f0e24ab3dac349e0de80d2018832e (diff)
swap: make each swap partition have one address_space
When I use several fast SSD to do swap, swapper_space.tree_lock is heavily contended. This makes each swap partition have one address_space to reduce the lock contention. There is an array of address_space for swap. The swap entry type is the index to the array. In my test with 3 SSD, this increases the swapout throughput 20%. [akpm@linux-foundation.org: revert unneeded change to __add_to_swap_cache] Signed-off-by: Shaohua Li <shli@fusionio.com> Cc: Hugh Dickins <hughd@google.com> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/mincore.c')
1 files changed, 3 insertions, 2 deletions
diff --git a/mm/mincore.c b/mm/mincore.c
index 936b4cee8cb..da2be56a7b8 100644
--- a/mm/mincore.c
+++ b/mm/mincore.c
@@ -75,7 +75,7 @@ static unsigned char mincore_page(struct address_space *mapping, pgoff_t pgoff)
/* shmem/tmpfs may return swap: account for swapcache page too. */
if (radix_tree_exceptional_entry(page)) {
swp_entry_t swap = radix_to_swp_entry(page);
- page = find_get_page(&swapper_space, swap.val);
+ page = find_get_page(swap_address_space(swap), swap.val);
if (page) {
@@ -135,7 +135,8 @@ static void mincore_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
} else {
pgoff = entry.val;
- *vec = mincore_page(&swapper_space, pgoff);
+ *vec = mincore_page(swap_address_space(entry),
+ pgoff);
*vec = 1;