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Fix congestion_wait() sync/async vs read/write confusion

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Commit 1faa16d228 accidentally broke
the bdi congestion wait queue logic, causing us to wait on congestion
for WRITE (== 1) when we really wanted BLK_RW_ASYNC (== 0) instead.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This commit is contained in:
Jens Axboe
2009-07-09 14:52:32 +02:00
committed by Jens Axboe
parent c2cc49a2f8
commit 8aa7e847d8
16 changed files with 43 additions and 40 deletions
Download Patch File Download Diff File Expand all files Collapse all files

7
mm/backing-dev.c
View File

@@ -283,7 +283,6 @@ static wait_queue_head_t congestion_wqh[2] = {
__WAIT_QUEUE_HEAD_INITIALIZER(congestion_wqh[1])
};
void clear_bdi_congested(struct backing_dev_info *bdi, int sync)
{
enum bdi_state bit;
@@ -308,18 +307,18 @@ EXPORT_SYMBOL(set_bdi_congested);
/**
* congestion_wait - wait for a backing_dev to become uncongested
* @rw: READ or WRITE
* @sync: SYNC or ASYNC IO
* @timeout: timeout in jiffies
*
* Waits for up to @timeout jiffies for a backing_dev (any backing_dev) to exit
* write congestion. If no backing_devs are congested then just wait for the
* next write to be completed.
*/
long congestion_wait(int rw, long timeout)
long congestion_wait(int sync, long timeout)
{
long ret;
DEFINE_WAIT(wait);
wait_queue_head_t *wqh = &congestion_wqh[rw];
wait_queue_head_t *wqh = &congestion_wqh[sync];
prepare_to_wait(wqh, &wait, TASK_UNINTERRUPTIBLE);
ret = io_schedule_timeout(timeout);

2
mm/memcontrol.c
View File

@@ -1973,7 +1973,7 @@ try_to_free:
if (!progress) {
nr_retries--;
/* maybe some writeback is necessary */
congestion_wait(WRITE, HZ/10);
congestion_wait(BLK_RW_ASYNC, HZ/10);
}
}

8
mm/page-writeback.c
View File

@@ -575,7 +575,7 @@ static void balance_dirty_pages(struct address_space *mapping)
if (pages_written >= write_chunk)
break; /* We've done our duty */
congestion_wait(WRITE, HZ/10);
congestion_wait(BLK_RW_ASYNC, HZ/10);
}
if (bdi_nr_reclaimable + bdi_nr_writeback < bdi_thresh &&
@@ -669,7 +669,7 @@ void throttle_vm_writeout(gfp_t gfp_mask)
if (global_page_state(NR_UNSTABLE_NFS) +
global_page_state(NR_WRITEBACK) <= dirty_thresh)
break;
congestion_wait(WRITE, HZ/10);
congestion_wait(BLK_RW_ASYNC, HZ/10);
/*
* The caller might hold locks which can prevent IO completion
@@ -715,7 +715,7 @@ static void background_writeout(unsigned long _min_pages)
if (wbc.nr_to_write > 0 || wbc.pages_skipped > 0) {
/* Wrote less than expected */
if (wbc.encountered_congestion || wbc.more_io)
congestion_wait(WRITE, HZ/10);
congestion_wait(BLK_RW_ASYNC, HZ/10);
else
break;
}
@@ -787,7 +787,7 @@ static void wb_kupdate(unsigned long arg)
writeback_inodes(&wbc);
if (wbc.nr_to_write > 0) {
if (wbc.encountered_congestion || wbc.more_io)
congestion_wait(WRITE, HZ/10);
congestion_wait(BLK_RW_ASYNC, HZ/10);
else
break; /* All the old data is written */
}

4
mm/page_alloc.c
View File

@@ -1666,7 +1666,7 @@ __alloc_pages_high_priority(gfp_t gfp_mask, unsigned int order,
preferred_zone, migratetype);
if (!page && gfp_mask & __GFP_NOFAIL)
congestion_wait(WRITE, HZ/50);
congestion_wait(BLK_RW_ASYNC, HZ/50);
} while (!page && (gfp_mask & __GFP_NOFAIL));
return page;
@@ -1831,7 +1831,7 @@ rebalance:
pages_reclaimed += did_some_progress;
if (should_alloc_retry(gfp_mask, order, pages_reclaimed)) {
/* Wait for some write requests to complete then retry */
congestion_wait(WRITE, HZ/50);
congestion_wait(BLK_RW_ASYNC, HZ/50);
goto rebalance;
}

8
mm/vmscan.c
View File

@@ -1104,7 +1104,7 @@ static unsigned long shrink_inactive_list(unsigned long max_scan,
*/
if (nr_freed < nr_taken && !current_is_kswapd() &&
lumpy_reclaim) {
congestion_wait(WRITE, HZ/10);
congestion_wait(BLK_RW_ASYNC, HZ/10);
/*
* The attempt at page out may have made some
@@ -1721,7 +1721,7 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist,
/* Take a nap, wait for some writeback to complete */
if (sc->nr_scanned && priority < DEF_PRIORITY - 2)
congestion_wait(WRITE, HZ/10);
congestion_wait(BLK_RW_ASYNC, HZ/10);
}
/* top priority shrink_zones still had more to do? don't OOM, then */
if (!sc->all_unreclaimable && scanning_global_lru(sc))
@@ -1960,7 +1960,7 @@ loop_again:
* another pass across the zones.
*/
if (total_scanned && priority < DEF_PRIORITY - 2)
congestion_wait(WRITE, HZ/10);
congestion_wait(BLK_RW_ASYNC, HZ/10);
/*
* We do this so kswapd doesn't build up large priorities for
@@ -2233,7 +2233,7 @@ unsigned long shrink_all_memory(unsigned long nr_pages)
goto out;
if (sc.nr_scanned && prio < DEF_PRIORITY - 2)
congestion_wait(WRITE, HZ / 10);
congestion_wait(BLK_RW_ASYNC, HZ / 10);
}
}