lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

[PATCH] Swap Migration V5: PF_SWAPWRITE to allow writing to swap

Browse Source 
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>
This commit is contained in:
Christoph Lameter
2006-01-08 01:00:47 -08:00
committed by Linus Torvalds
parent 21eac81f25
commit 930d915252
3 changed files with 4 additions and 5 deletions
Download Patch File Download Diff File Expand all files Collapse all files

1
include/linux/sched.h
View File

@@ -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_SYNCWRITE 0x00200000 /* I am doing a sync write */
#define PF_BORROWED_MM 0x00400000 /* I am a kthread doing use_mm */ #define PF_BORROWED_MM 0x00400000 /* I am a kthread doing use_mm */
#define PF_RANDOMIZE 0x00800000 /* randomize virtual address space */ #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 * Only the _current_ task can read/write to tsk->flags, but other

2
mm/pdflush.c
View File

@@ -90,7 +90,7 @@ struct pdflush_work {
static int __pdflush(struct pdflush_work *my_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->fn = NULL;
my_work->who = current; my_work->who = current;
INIT_LIST_HEAD(&my_work->list); INIT_LIST_HEAD(&my_work->list);

6
mm/vmscan.c
View File

@@ -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) static int may_write_to_queue(struct backing_dev_info *bdi)
{ {
if (current_is_kswapd()) if (current->flags & PF_SWAPWRITE)
return 1;
if (current_is_pdflush()) /* This is unlikely, but why not... */
return 1; return 1;
if (!bdi_write_congested(bdi)) if (!bdi_write_congested(bdi))
return 1; return 1;
@@ -1299,7 +1297,7 @@ static int kswapd(void *p)
* us from recursively trying to free more memory as we're * us from recursively trying to free more memory as we're
* trying to free the first piece of memory in the first place). * 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; order = 0;
for ( ; ; ) { for ( ; ; ) {