From: Ashwin Chaugule Date: Thu, 7 Dec 2006 04:31:54 +0000 (-0800) Subject: [PATCH] grab swap token reordered X-Git-Tag: v2.6.20-rc1~145^2^2~349 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=098fe651f7e9d759d1117c78c1a642b9b3945922;p=linux-2.6 [PATCH] grab swap token reordered Make sure the contention for the token happens _before_ any read-in and kicks the swap-token algo only when the VM is under pressure. Signed-off-by: Ashwin Chaugule Cc: Rik van Riel Cc: Peter Zijlstra Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/mm/filemap.c b/mm/filemap.c index 13df01c504..af7e2f5cae 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1445,7 +1445,6 @@ no_cached_page: * effect. */ error = page_cache_read(file, pgoff); - grab_swap_token(); /* * The page we want has now been added to the page cache. diff --git a/mm/memory.c b/mm/memory.c index 156861fcac..a07120da86 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1991,6 +1991,7 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma, delayacct_set_flag(DELAYACCT_PF_SWAPIN); page = lookup_swap_cache(entry); if (!page) { + grab_swap_token(); /* Contend for token _before_ read-in */ swapin_readahead(entry, address, vma); page = read_swap_cache_async(entry, vma, address); if (!page) { @@ -2008,7 +2009,6 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma, /* Had to read the page from swap area: Major fault */ ret = VM_FAULT_MAJOR; count_vm_event(PGMAJFAULT); - grab_swap_token(); } delayacct_clear_flag(DELAYACCT_PF_SWAPIN);