3.14-stable review patch. If anyone has any objections, please let me know.
------------------ From: David Rientjes <[email protected]> commit aeef4b83806f49a0c454b7d4578671b71045bee2 upstream. Async compaction terminates prematurely when need_resched(), see compact_checklock_irqsave(). This can never trigger, however, if the cond_resched() in isolate_migratepages_range() always takes care of the scheduling. If the cond_resched() actually triggers, then terminate this pageblock scan for async compaction as well. Signed-off-by: David Rientjes <[email protected]> Acked-by: Mel Gorman <[email protected]> Acked-by: Vlastimil Babka <[email protected]> Cc: Mel Gorman <[email protected]> Cc: Vlastimil Babka <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> Signed-off-by: Mel Gorman <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- mm/compaction.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) --- a/mm/compaction.c +++ b/mm/compaction.c @@ -494,8 +494,13 @@ isolate_migratepages_range(struct zone * return 0; } + if (cond_resched()) { + /* Async terminates prematurely on need_resched() */ + if (cc->mode == MIGRATE_ASYNC) + return 0; + } + /* Time to isolate some pages for migration */ - cond_resched(); for (; low_pfn < end_pfn; low_pfn++) { /* give a chance to irqs before checking need_resched() */ if (locked && !(low_pfn % SWAP_CLUSTER_MAX)) { -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
