From 32691f0fbe41a52eee811496205dc4828991b399 Mon Sep 17 00:00:00 2001 From: Andrey Ryabinin Date: Wed, 3 May 2017 14:56:06 -0700 Subject: [PATCH] mm/truncate: bail out early from invalidate_inode_pages2_range() if mapping is empty If mapping is empty (both ->nrpages and ->nrexceptional is zero) we can avoid pointless lookups in empty radix tree and bail out immediately after cleancache invalidation. Link: http://lkml.kernel.org/r/20170424164135.22350-4-aryabinin@virtuozzo.com Signed-off-by: Andrey Ryabinin Reviewed-by: Jan Kara Acked-by: Konrad Rzeszutek Wilk Cc: Alexander Viro Cc: Ross Zwisler Cc: Jens Axboe Cc: Johannes Weiner Cc: Alexey Kuznetsov Cc: Christoph Hellwig Cc: Nikolay Borisov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/truncate.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/mm/truncate.c b/mm/truncate.c index 6263affdef88..8f12b0e2e85f 100644 --- a/mm/truncate.c +++ b/mm/truncate.c @@ -624,6 +624,9 @@ int invalidate_inode_pages2_range(struct address_space *mapping, int did_range_unmap = 0; cleancache_invalidate_inode(mapping); + if (mapping->nrpages == 0 && mapping->nrexceptional == 0) + return 0; + pagevec_init(&pvec, 0); index = start; while (index <= end && pagevec_lookup_entries(&pvec, mapping, index, -- 2.20.1