From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 29ACFC47E49 for ; Mon, 4 Nov 2019 22:04:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id ED9892245B for ; Mon, 4 Nov 2019 22:04:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572905047; bh=2ClVHOIAbdKNuF68XuAEorz5HrkQpIM9Eg5qR3r4f8U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Bo6T0Djr8Q+zvk6BI4E34g/ZDh4mFYGduxdY0UmCzppApuppvLHRXm2uSl614iXnj qNkQVgy5j2q/lkiWsDLzZ3NgyRGk/8i9ga/KLnup1kRZ6fRo9p3Lizey7MEVdCM/z1 vh/O7ZJvMqLDc3JTwZksrtpc/frK27kWBCH8pgOo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388560AbfKDWEF (ORCPT ); Mon, 4 Nov 2019 17:04:05 -0500 Received: from mail.kernel.org ([198.145.29.99]:34656 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389598AbfKDWEF (ORCPT ); Mon, 4 Nov 2019 17:04:05 -0500 Received: from localhost (6.204-14-84.ripe.coltfrance.com [84.14.204.6]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 3D7E42084D; Mon, 4 Nov 2019 22:04:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572905044; bh=2ClVHOIAbdKNuF68XuAEorz5HrkQpIM9Eg5qR3r4f8U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hb2FFLwoNYFY76qgVxGFUX5SjISHLJMhxknA4Zra7DnEbevkOx1j/XLEaa5MqSOwW HjW8W2j/+v8WKmQU4pCzxD3sqi02Kw8YvI58JQlvJCjcxx3m2HlfXOhUTPt1HkC8DS ZuiflQl9hvyVOMAKfGT1mKBYLBpqD2JQCkau/Eeo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Mikulas Patocka , Nikos Tsironis , Mike Snitzer , Sasha Levin Subject: [PATCH 5.3 002/163] dm snapshot: introduce account_start_copy() and account_end_copy() Date: Mon, 4 Nov 2019 22:43:12 +0100 Message-Id: <20191104212140.260491623@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191104212140.046021995@linuxfoundation.org> References: <20191104212140.046021995@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Mikulas Patocka [ Upstream commit a2f83e8b0c82c9500421a26c49eb198b25fcdea3 ] This simple refactoring moves code for modifying the semaphore cow_count into separate functions to prepare for changes that will extend these methods to provide for a more sophisticated mechanism for COW throttling. Signed-off-by: Mikulas Patocka Reviewed-by: Nikos Tsironis Signed-off-by: Mike Snitzer Signed-off-by: Sasha Levin --- drivers/md/dm-snap.c | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-) diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c index f150f5c5492b9..da3bd1794ee05 100644 --- a/drivers/md/dm-snap.c +++ b/drivers/md/dm-snap.c @@ -1512,6 +1512,16 @@ static void snapshot_dtr(struct dm_target *ti) kfree(s); } +static void account_start_copy(struct dm_snapshot *s) +{ + down(&s->cow_count); +} + +static void account_end_copy(struct dm_snapshot *s) +{ + up(&s->cow_count); +} + /* * Flush a list of buffers. */ @@ -1732,7 +1742,7 @@ static void copy_callback(int read_err, unsigned long write_err, void *context) rb_link_node(&pe->out_of_order_node, parent, p); rb_insert_color(&pe->out_of_order_node, &s->out_of_order_tree); } - up(&s->cow_count); + account_end_copy(s); } /* @@ -1756,7 +1766,7 @@ static void start_copy(struct dm_snap_pending_exception *pe) dest.count = src.count; /* Hand over to kcopyd */ - down(&s->cow_count); + account_start_copy(s); dm_kcopyd_copy(s->kcopyd_client, &src, 1, &dest, 0, copy_callback, pe); } @@ -1776,7 +1786,7 @@ static void start_full_bio(struct dm_snap_pending_exception *pe, pe->full_bio = bio; pe->full_bio_end_io = bio->bi_end_io; - down(&s->cow_count); + account_start_copy(s); callback_data = dm_kcopyd_prepare_callback(s->kcopyd_client, copy_callback, pe); @@ -1866,7 +1876,7 @@ static void zero_callback(int read_err, unsigned long write_err, void *context) struct bio *bio = context; struct dm_snapshot *s = bio->bi_private; - up(&s->cow_count); + account_end_copy(s); bio->bi_status = write_err ? BLK_STS_IOERR : 0; bio_endio(bio); } @@ -1880,7 +1890,7 @@ static void zero_exception(struct dm_snapshot *s, struct dm_exception *e, dest.sector = bio->bi_iter.bi_sector; dest.count = s->store->chunk_size; - down(&s->cow_count); + account_start_copy(s); WARN_ON_ONCE(bio->bi_private); bio->bi_private = s; dm_kcopyd_zero(s->kcopyd_client, 1, &dest, 0, zero_callback, bio); -- 2.20.1