From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: [patch 064/118] mm/huge_memory.c: reduce critical section protected by split_queue_lock Date: Thu, 30 Jan 2020 22:14:35 -0800 Message-ID: <20200131061435.YbgVMa_lG%akpm@linux-foundation.org> References: <20200130221021.5f0211c56346d5485af07923@linux-foundation.org> Reply-To: linux-kernel@vger.kernel.org Return-path: Received: from mail.kernel.org ([198.145.29.99]:34366 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728077AbgAaGOg (ORCPT ); Fri, 31 Jan 2020 01:14:36 -0500 In-Reply-To: <20200130221021.5f0211c56346d5485af07923@linux-foundation.org> Sender: mm-commits-owner@vger.kernel.org List-Id: mm-commits@vger.kernel.org To: akpm@linux-foundation.org, kirill.shutemov@linux.intel.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, richardw.yang@linux.intel.com, torvalds@linux-foundation.org From: Wei Yang Subject: mm/huge_memory.c: reduce critical section protected by split_queue_lock split_queue_lock protects data in struct deferred_split. We can release the lock after delete the page from deferred_split_queue. This patch moves the THP accounting out of the lock protection, which is introduced in commit 65c453778aea ("mm, rmap: account shmem thp pages"). Link: http://lkml.kernel.org/r/20200110025516.23996-1-richardw.yang@linux.intel.com Signed-off-by: Wei Yang Reviewed-by: Andrew Morton Acked-by: Kirill A. Shutemov Signed-off-by: Andrew Morton --- mm/huge_memory.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/mm/huge_memory.c~mm-huge_memoryc-reduce-critical-section-protected-by-split_queue_lock +++ a/mm/huge_memory.c @@ -2799,6 +2799,7 @@ int split_huge_page_to_list(struct page ds_queue->split_queue_len--; list_del(page_deferred_list(head)); } + spin_unlock(&ds_queue->split_queue_lock); if (mapping) { if (PageSwapBacked(head)) __dec_node_page_state(head, NR_SHMEM_THPS); @@ -2806,7 +2807,6 @@ int split_huge_page_to_list(struct page __dec_node_page_state(head, NR_FILE_THPS); } - spin_unlock(&ds_queue->split_queue_lock); __split_huge_page(page, list, end, flags); if (PageSwapCache(head)) { swp_entry_t entry = { .val = page_private(head) }; _