Using lruvec locking to replace pgdat lru_lock. and then unfold
compact_unlock_should_abort() to fit the replacement.
Signed-off-by: Alex Shi <alex....@linux.alibaba.com>
Cc: Mel Gorman <mgor...@techsingularity.net>
Cc: Vlastimil Babka <vba...@suse.cz>
Cc: Qian Cai <c...@lca.pw>
Cc: Andrey Ryabinin <aryabi...@virtuozzo.com>
Cc: Andrew Morton <a...@linux-foundation.org>
Cc: Tejun Heo <t...@kernel.org>
Cc: cgro...@vger.kernel.org
Cc: linux...@kvack.org
Cc: linux-kernel@vger.kernel.org
---
mm/compaction.c | 48 ++++++++++++++++++++++++++++++------------------
1 file changed, 30 insertions(+), 18 deletions(-)
diff --git a/mm/compaction.c b/mm/compaction.c
index 9a737f343183..8877f38410d8 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -785,7 +785,7 @@ static bool too_many_isolated(pg_data_t *pgdat)
unsigned long nr_scanned = 0, nr_isolated = 0;
struct lruvec *lruvec;
unsigned long flags = 0;
- bool locked = false;
+ struct lruvec *locked_lruvec = NULL;
struct page *page = NULL, *valid_page = NULL;
unsigned long start_pfn = low_pfn;
bool skip_on_failure = false;
@@ -845,11 +845,20 @@ static bool too_many_isolated(pg_data_t *pgdat)
* contention, to give chance to IRQs. Abort completely if
* a fatal signal is pending.
*/
- if (!(low_pfn % SWAP_CLUSTER_MAX)
- && compact_unlock_should_abort(&pgdat->lruvec.lru_lock,
- flags, &locked, cc)) {
- low_pfn = 0;
- goto fatal_pending;
+ if (!(low_pfn % SWAP_CLUSTER_MAX)) {
+ if (locked_lruvec) {
+
spin_unlock_irqrestore(&locked_lruvec->lru_lock, flags);
+ locked_lruvec = NULL;
+ }
+
+ if (fatal_signal_pending(current)) {
+ cc->contended = true;
+
+ low_pfn = 0;
+ goto fatal_pending;
+ }
+
+ cond_resched();
}
if (!pfn_valid_within(low_pfn))
@@ -918,10 +927,10 @@ static bool too_many_isolated(pg_data_t *pgdat)
*/
if (unlikely(__PageMovable(page)) &&
!PageIsolated(page)) {
- if (locked) {
-
spin_unlock_irqrestore(&pgdat->lruvec.lru_lock,
+ if (locked_lruvec) {
+
spin_unlock_irqrestore(&locked_lruvec->lru_lock,
flags);
- locked = false;
+ locked_lruvec = NULL;
}
if (!isolate_movable_page(page, isolate_mode))
@@ -947,10 +956,14 @@ static bool too_many_isolated(pg_data_t *pgdat)
if (!(cc->gfp_mask & __GFP_FS) && page_mapping(page))
goto isolate_fail;
+ lruvec = mem_cgroup_page_lruvec(page, pgdat);
+
/* If we already hold the lock, we can skip some rechecking */
- if (!locked) {
- locked = compact_lock_irqsave(&pgdat->lruvec.lru_lock,
- &flags, cc);
+ if (lruvec != locked_lruvec) {
+ if (compact_lock_irqsave(&lruvec->lru_lock, &flags, cc))
+ locked_lruvec = lruvec;
+
+ sync_lruvec_pgdat(lruvec, pgdat);
/* Try get exclusive access under lock */
if (!skip_updated) {
@@ -974,7 +987,6 @@ static bool too_many_isolated(pg_data_t *pgdat)
}
}
- lruvec = mem_cgroup_page_lruvec(page, pgdat);
/* Try isolate the page */
if (__isolate_lru_page(page, isolate_mode) != 0)
@@ -1015,9 +1027,9 @@ static bool too_many_isolated(pg_data_t *pgdat)
* page anyway.
*/
if (nr_isolated) {
- if (locked) {
- spin_unlock_irqrestore(&pgdat->lruvec.lru_lock,
flags);
- locked = false;
+ if (locked_lruvec) {
+
spin_unlock_irqrestore(&locked_lruvec->lru_lock, flags);
+ locked_lruvec = NULL;
}
putback_movable_pages(&cc->migratepages);
cc->nr_migratepages = 0;
@@ -1042,8 +1054,8 @@ static bool too_many_isolated(pg_data_t *pgdat)
low_pfn = end_pfn;
isolate_abort:
- if (locked)
- spin_unlock_irqrestore(&pgdat->lruvec.lru_lock, flags);
+ if (locked_lruvec)
+ spin_unlock_irqrestore(&locked_lruvec->lru_lock, flags);
/*
* Updated the cached scanner pfn once the pageblock has been scanned
--
1.8.3.1
