summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorChristoph Lameter <clameter@sgi.com>2006-01-08 01:00:47 -0800
committerLinus Torvalds <torvalds@g5.osdl.org>2006-01-08 20:12:41 -0800
commit930d915252edda7042c944ed3c30194a2f9fe163 (patch)
tree620452f11a9949943765b7a28e5b919f40f32b12
parent21eac81f252fe31c3cf64b805a1e8652192f3a3b (diff)
[PATCH] Swap Migration V5: PF_SWAPWRITE to allow writing to swap
Add PF_SWAPWRITE to control a processes permission to write to swap. - Use PF_SWAPWRITE in may_write_to_queue() instead of checking for kswapd and pdflush - Set PF_SWAPWRITE flag for kswapd and pdflush Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
-rw-r--r--include/linux/sched.h1
-rw-r--r--mm/pdflush.c2
-rw-r--r--mm/vmscan.c6
3 files changed, 4 insertions, 5 deletions
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 7da33619d5d0..a74662077d60 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -895,6 +895,7 @@ do { if (atomic_dec_and_test(&(tsk)->usage)) __put_task_struct(tsk); } while(0)
#define PF_SYNCWRITE 0x00200000 /* I am doing a sync write */
#define PF_BORROWED_MM 0x00400000 /* I am a kthread doing use_mm */
#define PF_RANDOMIZE 0x00800000 /* randomize virtual address space */
+#define PF_SWAPWRITE 0x01000000 /* Allowed to write to swap */
/*
* Only the _current_ task can read/write to tsk->flags, but other
diff --git a/mm/pdflush.c b/mm/pdflush.c
index 52822c98c489..c4b6d0afd736 100644
--- a/mm/pdflush.c
+++ b/mm/pdflush.c
@@ -90,7 +90,7 @@ struct pdflush_work {
static int __pdflush(struct pdflush_work *my_work)
{
- current->flags |= PF_FLUSHER;
+ current->flags |= PF_FLUSHER | PF_SWAPWRITE;
my_work->fn = NULL;
my_work->who = current;
INIT_LIST_HEAD(&my_work->list);
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 261a56ee11b6..6c30a8c59795 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -268,9 +268,7 @@ static inline int is_page_cache_freeable(struct page *page)
static int may_write_to_queue(struct backing_dev_info *bdi)
{
- if (current_is_kswapd())
- return 1;
- if (current_is_pdflush()) /* This is unlikely, but why not... */
+ if (current->flags & PF_SWAPWRITE)
return 1;
if (!bdi_write_congested(bdi))
return 1;
@@ -1299,7 +1297,7 @@ static int kswapd(void *p)
* us from recursively trying to free more memory as we're
* trying to free the first piece of memory in the first place).
*/
- tsk->flags |= PF_MEMALLOC|PF_KSWAPD;
+ tsk->flags |= PF_MEMALLOC | PF_SWAPWRITE | PF_KSWAPD;
order = 0;
for ( ; ; ) {