aboutsummaryrefslogtreecommitdiff
path: root/fs/gfs2/incore.h
diff options
context:
space:
mode:
authorBenjamin Marzinski <bmarzins@redhat.com>2007-08-23 13:19:05 -0500
committerSteven Whitehouse <swhiteho@redhat.com>2007-10-10 08:55:48 +0100
commitc4f68a130fc1795e4a75ec5bdaf9e85d86c22419 (patch)
tree37251ae5634d4b73b5224e3e8679f92472de0ebe /fs/gfs2/incore.h
parentd1e2777d4f419a865ddccdb9b3412021d0e4de51 (diff)
[GFS2] delay glock demote for a minimum hold time
When a lot of IO, with some distributed mmap IO, is run on a GFS2 filesystem in a cluster, it will deadlock. The reason is that do_no_page() will repeatedly call gfs2_sharewrite_nopage(), because each node keeps giving up the glock too early, and is forced to call unmap_mapping_range(). This bumps the mapping->truncate_count sequence count, forcing do_no_page() to retry. This patch institutes a minimum glock hold time a tenth a second. This insures that even in heavy contention cases, the node has enough time to get some useful work done before it gives up the glock. A second issue is that when gfs2_glock_dq() is called from within a page fault to demote a lock, and the associated page needs to be written out, it will try to acqire a lock on it, but it has already been locked at a higher level. This patch puts makes gfs2_glock_dq() use the work queue as well, to avoid this issue. This is the same patch as Steve Whitehouse originally proposed to fix this issue, execpt that gfs2_glock_dq() now grabs a reference to the glock before it queues up the work on it. Signed-off-by: Benjamin E. Marzinski <bmarzins@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Diffstat (limited to 'fs/gfs2/incore.h')
-rw-r--r--fs/gfs2/incore.h5
1 files changed, 5 insertions, 0 deletions
diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h
index 1390b30daf1..23b611aa70d 100644
--- a/fs/gfs2/incore.h
+++ b/fs/gfs2/incore.h
@@ -11,6 +11,7 @@
#define __INCORE_DOT_H__
#include <linux/fs.h>
+#include <linux/workqueue.h>
#define DIO_WAIT 0x00000010
#define DIO_METADATA 0x00000020
@@ -130,6 +131,7 @@ struct gfs2_glock_operations {
int (*go_lock) (struct gfs2_holder *gh);
void (*go_unlock) (struct gfs2_holder *gh);
const int go_type;
+ const unsigned long go_min_hold_time;
};
enum {
@@ -161,6 +163,7 @@ enum {
GLF_LOCK = 1,
GLF_STICKY = 2,
GLF_DEMOTE = 3,
+ GLF_PENDING_DEMOTE = 4,
GLF_DIRTY = 5,
};
@@ -193,6 +196,7 @@ struct gfs2_glock {
u64 gl_vn;
unsigned long gl_stamp;
+ unsigned long gl_tchange;
void *gl_object;
struct list_head gl_reclaim;
@@ -203,6 +207,7 @@ struct gfs2_glock {
struct gfs2_log_element gl_le;
struct list_head gl_ail_list;
atomic_t gl_ail_count;
+ struct delayed_work gl_work;
};
struct gfs2_alloc {