From: Mel Gorman <mgorman@techsingularity.net>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: David Rientjes <rientjes@google.com>,
Andrea Arcangeli <aarcange@redhat.com>,
Vlastimil Babka <vbabka@suse.cz>,
Linux List Kernel Mailing <linux-kernel@vger.kernel.org>,
Linux-MM <linux-mm@kvack.org>,
Mel Gorman <mgorman@techsingularity.net>
Subject: [PATCH 16/22] mm, compaction: Rework compact_should_abort as compact_check_resched
Date: Fri, 18 Jan 2019 17:51:30 +0000 [thread overview]
Message-ID: <20190118175136.31341-17-mgorman@techsingularity.net> (raw)
In-Reply-To: <20190118175136.31341-1-mgorman@techsingularity.net>
With incremental changes, compact_should_abort no longer makes
any documented sense. Rename to compact_check_resched and update the
associated comments. There is no benefit other than reducing redundant
code and making the intent slightly clearer. It could potentially be
merged with earlier patches but it just makes the review slightly
harder.
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
---
mm/compaction.c | 61 ++++++++++++++++++++++-----------------------------------
1 file changed, 23 insertions(+), 38 deletions(-)
diff --git a/mm/compaction.c b/mm/compaction.c
index 829540f6f3da..9aa71945255d 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -404,6 +404,21 @@ static bool compact_lock_irqsave(spinlock_t *lock, unsigned long *flags,
return true;
}
+/*
+ * Aside from avoiding lock contention, compaction also periodically checks
+ * need_resched() and records async compaction as contended if necessary.
+ */
+static inline void compact_check_resched(struct compact_control *cc)
+{
+ /* async compaction aborts if contended */
+ if (need_resched()) {
+ if (cc->mode == MIGRATE_ASYNC)
+ cc->contended = true;
+
+ cond_resched();
+ }
+}
+
/*
* Compaction requires the taking of some coarse locks that are potentially
* very heavily contended. The lock should be periodically unlocked to avoid
@@ -432,33 +447,7 @@ static bool compact_unlock_should_abort(spinlock_t *lock,
return true;
}
- if (need_resched()) {
- if (cc->mode == MIGRATE_ASYNC)
- cc->contended = true;
- cond_resched();
- }
-
- return false;
-}
-
-/*
- * Aside from avoiding lock contention, compaction also periodically checks
- * need_resched() and either schedules in sync compaction or aborts async
- * compaction. This is similar to what compact_unlock_should_abort() does, but
- * is used where no lock is concerned.
- *
- * Returns false when no scheduling was needed, or sync compaction scheduled.
- * Returns true when async compaction should abort.
- */
-static inline bool compact_should_abort(struct compact_control *cc)
-{
- /* async compaction aborts if contended */
- if (need_resched()) {
- if (cc->mode == MIGRATE_ASYNC)
- cc->contended = true;
-
- cond_resched();
- }
+ compact_check_resched(cc);
return false;
}
@@ -747,8 +736,7 @@ isolate_migratepages_block(struct compact_control *cc, unsigned long low_pfn,
return 0;
}
- if (compact_should_abort(cc))
- return 0;
+ compact_check_resched(cc);
if (cc->direct_compaction && (cc->mode == MIGRATE_ASYNC)) {
skip_on_failure = true;
@@ -1379,12 +1367,10 @@ static void isolate_freepages(struct compact_control *cc)
isolate_start_pfn = block_start_pfn) {
/*
* This can iterate a massively long zone without finding any
- * suitable migration targets, so periodically check if we need
- * to schedule, or even abort async compaction.
+ * suitable migration targets, so periodically check resched.
*/
- if (!(block_start_pfn % (SWAP_CLUSTER_MAX * pageblock_nr_pages))
- && compact_should_abort(cc))
- break;
+ if (!(block_start_pfn % (SWAP_CLUSTER_MAX * pageblock_nr_pages)))
+ compact_check_resched(cc);
page = pageblock_pfn_to_page(block_start_pfn, block_end_pfn,
zone);
@@ -1675,11 +1661,10 @@ static isolate_migrate_t isolate_migratepages(struct zone *zone,
/*
* This can potentially iterate a massively long zone with
* many pageblocks unsuitable, so periodically check if we
- * need to schedule, or even abort async compaction.
+ * need to schedule.
*/
- if (!(low_pfn % (SWAP_CLUSTER_MAX * pageblock_nr_pages))
- && compact_should_abort(cc))
- break;
+ if (!(low_pfn % (SWAP_CLUSTER_MAX * pageblock_nr_pages)))
+ compact_check_resched(cc);
page = pageblock_pfn_to_page(block_start_pfn, block_end_pfn,
zone);
--
2.16.4
next prev parent reply other threads:[~2019-01-18 17:54 UTC|newest]
Thread overview: 45+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-01-18 17:51 [PATCH 00/22] Increase success rates and reduce latency of compaction v3 Mel Gorman
2019-01-18 17:51 ` [PATCH 01/22] mm, compaction: Shrink compact_control Mel Gorman
2019-01-18 17:51 ` [PATCH 02/22] mm, compaction: Rearrange compact_control Mel Gorman
2019-01-18 17:51 ` [PATCH 03/22] mm, compaction: Remove last_migrated_pfn from compact_control Mel Gorman
2019-01-18 17:51 ` [PATCH 04/22] mm, compaction: Remove unnecessary zone parameter in some instances Mel Gorman
2019-01-18 17:51 ` [PATCH 05/22] mm, compaction: Rename map_pages to split_map_pages Mel Gorman
2019-01-18 17:51 ` [PATCH 06/22] mm, migrate: Immediately fail migration of a page with no migration handler Mel Gorman
2019-01-18 17:51 ` [PATCH 07/22] mm, compaction: Always finish scanning of a full pageblock Mel Gorman
2019-01-18 17:51 ` [PATCH 08/22] mm, compaction: Ignore the fragmentation avoidance boost for isolation and compaction Mel Gorman
2019-01-18 17:51 ` [PATCH 09/22] mm, compaction: Use free lists to quickly locate a migration source Mel Gorman
2019-01-31 13:55 ` Vlastimil Babka
2019-01-31 14:12 ` Vlastimil Babka
2019-02-01 15:06 ` Mel Gorman
2019-02-04 8:55 ` [PATCH] mm, compaction: Use free lists to quickly locate a migration source -fix Mel Gorman
2019-02-08 17:10 ` [PATCH 09/22] mm, compaction: Use free lists to quickly locate a migration source Vlastimil Babka
2019-01-18 17:51 ` [PATCH 10/22] mm, compaction: Keep migration source private to a single compaction instance Mel Gorman
2019-01-18 17:51 ` [PATCH 11/22] mm, compaction: Use free lists to quickly locate a migration target Mel Gorman
2019-01-31 14:52 ` Vlastimil Babka
2019-02-01 14:51 ` Mel Gorman
2019-02-01 14:58 ` Vlastimil Babka
2019-02-04 12:01 ` [PATCH] mm, compaction: Use free lists to quickly locate a migration source -fix Mel Gorman
2021-01-12 5:19 ` [PATCH] mm, compaction: make sure we isolate a valid freepage when high_pfn is used Rokudo Yan
2021-01-12 9:10 ` Mel Gorman
2021-01-12 9:47 ` [PATCH] mm, compaction: move high_pfn to the for loop scope Rokudo Yan
2021-01-12 10:45 ` Mel Gorman
2021-01-12 10:48 ` Vlastimil Babka
2021-01-12 22:27 ` Andrew Morton
2021-01-18 7:41 ` Rokudo Yan
2021-01-18 9:42 ` Mel Gorman
2019-01-18 17:51 ` [PATCH 12/22] mm, compaction: Avoid rescanning the same pageblock multiple times Mel Gorman
2019-01-18 17:51 ` [PATCH 13/22] mm, compaction: Finish pageblock scanning on contention Mel Gorman
2019-01-18 17:51 ` [PATCH 14/22] mm, compaction: Check early for huge pages encountered by the migration scanner Mel Gorman
2019-01-18 17:51 ` [PATCH 15/22] mm, compaction: Keep cached migration PFNs synced for unusable pageblocks Mel Gorman
2019-01-18 17:51 ` Mel Gorman [this message]
2019-01-18 17:51 ` [PATCH 17/22] mm, compaction: Do not consider a need to reschedule as contention Mel Gorman
2019-01-18 17:51 ` [PATCH 18/22] mm, compaction: Reduce premature advancement of the migration target scanner Mel Gorman
2019-01-18 17:51 ` [PATCH 19/22] mm, compaction: Round-robin the order while searching the free lists for a target Mel Gorman
2019-01-18 17:51 ` [PATCH 20/22] mm, compaction: Sample pageblocks for free pages Mel Gorman
2019-01-31 15:39 ` Vlastimil Babka
2019-01-18 17:51 ` [PATCH 21/22] mm, compaction: Be selective about what pageblocks to clear skip hints Mel Gorman
2019-01-31 15:45 ` Vlastimil Babka
2019-01-18 17:51 ` [PATCH 22/22] mm, compaction: Capture a page under direct compaction Mel Gorman
2019-01-31 16:11 ` Vlastimil Babka
2019-02-01 14:38 ` [PATCH] mm, compaction: Capture a page under direct compaction -fix Mel Gorman
2019-01-24 8:53 ` [PATCH 00/22] Increase success rates and reduce latency of compaction v3 Mel Gorman
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