From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752132AbeFENcw (ORCPT ); Tue, 5 Jun 2018 09:32:52 -0400 Received: from mail-qt0-f193.google.com ([209.85.216.193]:46290 "EHLO mail-qt0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751976AbeFEN34 (ORCPT ); Tue, 5 Jun 2018 09:29:56 -0400 X-Google-Smtp-Source: ADUXVKLAOpDJOxVE0IO45i2gjBkYdpZD1mePUwSMDyU0z/qOxe6+mf+oUVKT7NJPRh/iExmI96YNxA== From: Josef Bacik To: axboe@kernel.dk, kernel-team@fb.com, linux-block@vger.kernel.org, akpm@linux-foundation.org, hannes@cmpxchg.org, linux-kernel@vger.kernel.org, tj@kernel.org, linux-fsdevel@vger.kernel.org Cc: Josef Bacik Subject: [PATCH 04/13] blk: introduce REQ_SWAP Date: Tue, 5 Jun 2018 09:29:39 -0400 Message-Id: <20180605132948.1664-5-josef@toxicpanda.com> X-Mailer: git-send-email 2.14.3 In-Reply-To: <20180605132948.1664-1-josef@toxicpanda.com> References: <20180605132948.1664-1-josef@toxicpanda.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Josef Bacik Just like REQ_META, it's important to know the IO coming down is swap in order to guard against potential IO priority inversion issues with cgroups. Add REQ_SWAP and use it for all swap IO, and add it to our bio_issue_as_root_blkg helper. Signed-off-by: Josef Bacik Acked-by: Tejun Heo --- include/linux/blk-cgroup.h | 2 +- include/linux/blk_types.h | 3 ++- mm/page_io.c | 2 +- 3 files changed, 4 insertions(+), 3 deletions(-) diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h index b41292726c0f..a8f9ba8f33a4 100644 --- a/include/linux/blk-cgroup.h +++ b/include/linux/blk-cgroup.h @@ -254,7 +254,7 @@ static inline struct blkcg *bio_blkcg(struct bio *bio) */ static inline bool bio_issue_as_root_blkg(struct bio *bio) { - return (bio->bi_opf & REQ_META); + return (bio->bi_opf & (REQ_META | REQ_SWAP)) != 0; } /** diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index ff181df8c195..4f7ba397d37d 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -327,7 +327,7 @@ enum req_flag_bits { /* for driver use */ __REQ_DRV, - + __REQ_SWAP, /* swapping request. */ __REQ_NR_BITS, /* stops here */ }; @@ -349,6 +349,7 @@ enum req_flag_bits { #define REQ_NOUNMAP (1ULL << __REQ_NOUNMAP) #define REQ_DRV (1ULL << __REQ_DRV) +#define REQ_SWAP (1ULL << __REQ_SWAP) #define REQ_FAILFAST_MASK \ (REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | REQ_FAILFAST_DRIVER) diff --git a/mm/page_io.c b/mm/page_io.c index b41cf9644585..a552cb37e220 100644 --- a/mm/page_io.c +++ b/mm/page_io.c @@ -338,7 +338,7 @@ int __swap_writepage(struct page *page, struct writeback_control *wbc, ret = -ENOMEM; goto out; } - bio->bi_opf = REQ_OP_WRITE | wbc_to_write_flags(wbc); + bio->bi_opf = REQ_OP_WRITE | REQ_SWAP | wbc_to_write_flags(wbc); count_swpout_vm_event(page); set_page_writeback(page); unlock_page(page); -- 2.14.3