lkml.org 
[lkml]   [2005]   [Oct]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH 2/5] 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>

Index: linux-2.6.14-rc5-mm1/include/linux/sched.h
===================================================================
--- linux-2.6.14-rc5-mm1.orig/include/linux/sched.h 2005-10-24 10:27:29.000000000 -0700
+++ linux-2.6.14-rc5-mm1/include/linux/sched.h 2005-10-31 13:30:48.000000000 -0800
@@ -914,6 +914,7 @@ do { if (atomic_dec_and_test(&(tsk)->usa
#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 /* the process is allowed to write to swap */

/*
* Only the _current_ task can read/write to tsk->flags, but other
Index: linux-2.6.14-rc5-mm1/mm/vmscan.c
===================================================================
--- linux-2.6.14-rc5-mm1.orig/mm/vmscan.c 2005-10-31 13:21:57.000000000 -0800
+++ linux-2.6.14-rc5-mm1/mm/vmscan.c 2005-10-31 13:30:48.000000000 -0800
@@ -263,9 +263,7 @@ static inline int is_page_cache_freeable

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;
@@ -1289,7 +1287,7 @@ 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 ( ; ; ) {
Index: linux-2.6.14-rc5-mm1/mm/pdflush.c
===================================================================
--- linux-2.6.14-rc5-mm1.orig/mm/pdflush.c 2005-10-24 10:27:21.000000000 -0700
+++ linux-2.6.14-rc5-mm1/mm/pdflush.c 2005-10-31 13:30:48.000000000 -0800
@@ -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);
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
\
 
 \ /
  Last update: 2005-11-01 04:16    [W:0.169 / U:0.400 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site