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| author | Cesar Eduardo Barros <cesarb@cesarb.net> | 2011-03-22 16:33:16 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-22 17:44:06 -0700 |
| commit | e8e6c2ec403ecfaa226857d8204344c98fe12b7b (patch) | |
| tree | 93a3cdaf385c72ba1f98add399b34ba65608efff | |
| parent | 80b0df12b808bf8e8391afae1b43f5e529f76d89 (diff) | |
| download | linux-e8e6c2ec403ecfaa226857d8204344c98fe12b7b.tar.gz linux-e8e6c2ec403ecfaa226857d8204344c98fe12b7b.tar.bz2 linux-e8e6c2ec403ecfaa226857d8204344c98fe12b7b.zip | |
sys_swapon: do not depend on "type" after allocation
Within sys_swapon, after the swap_info entry has been allocated, we
always have type == p->type and swap_info[type] == p. Use this fact to
reduce the dependency on the "type" local variable within the function,
as a preparation to move the allocation of the swap_info entry to a
separate function.
Signed-off-by: Cesar Eduardo Barros <cesarb@cesarb.net>
Tested-by: Eric B Munson <emunson@mgebm.net>
Acked-by: Eric B Munson <emunson@mgebm.net>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujisu.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | mm/swapfile.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/mm/swapfile.c b/mm/swapfile.c index 971464470938..5238d8d15d78 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -1927,7 +1927,7 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags) for (i = 0; i < nr_swapfiles; i++) { struct swap_info_struct *q = swap_info[i]; - if (i == type || !q->swap_file) + if (q == p || !q->swap_file) continue; if (mapping == q->swap_file->f_mapping) goto bad_swap; @@ -2062,7 +2062,7 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags) } } - error = swap_cgroup_swapon(type, maxpages); + error = swap_cgroup_swapon(p->type, maxpages); if (error) goto bad_swap; @@ -2120,9 +2120,9 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags) } p->next = i; if (prev < 0) - swap_list.head = swap_list.next = type; + swap_list.head = swap_list.next = p->type; else - swap_info[prev]->next = type; + swap_info[prev]->next = p->type; spin_unlock(&swap_lock); mutex_unlock(&swapon_mutex); atomic_inc(&proc_poll_event); @@ -2136,7 +2136,7 @@ bad_swap: blkdev_put(bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL); } destroy_swap_extents(p); - swap_cgroup_swapoff(type); + swap_cgroup_swapoff(p->type); bad_swap_2: spin_lock(&swap_lock); p->swap_file = NULL; |