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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B9834C3F6B0 for ; Mon, 15 Aug 2022 20:46:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345097AbiHOUqz (ORCPT ); Mon, 15 Aug 2022 16:46:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34406 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345464AbiHOUn4 (ORCPT ); Mon, 15 Aug 2022 16:43:56 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 887FCB5E67; Mon, 15 Aug 2022 12:08:14 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 9EBF3B8107A; Mon, 15 Aug 2022 19:08:12 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E28F5C433C1; Mon, 15 Aug 2022 19:08:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1660590491; bh=rbSoHySHO4jMvEXKq37KUby7dmBgoSKFMYmjaT4M5W8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kvmdbwP5THZqeziZMQAPDFHtUTkWTBNctBiD0sxagHJaSykEYDB/OXe8tGfUPSznI TQBA28XOMQSF7rQBWXFV6fDE7PAHaG1K0KBLX23/LHAQ9H2X5UOydrQTanDVdr0hO+ Q6VANwE8tO+L1NSSoPhhsa4bbBZJk7Yhf8GiYAPY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Yu Kuai , Mikulas Patocka , Mike Snitzer , Sasha Levin Subject: [PATCH 5.18 0277/1095] dm writecache: count number of blocks written, not number of write bios Date: Mon, 15 Aug 2022 19:54:36 +0200 Message-Id: <20220815180441.230632036@linuxfoundation.org> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20220815180429.240518113@linuxfoundation.org> References: <20220815180429.240518113@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Mikulas Patocka [ Upstream commit b2676e1482af89714af6988ce5d31a84692e2530 ] Change dm-writecache, so that it counts the number of blocks written instead of the number of write bios. Bios can be split and requeued using the dm_accept_partial_bio function, so counting bios caused inaccurate results. Fixes: e3a35d03407c ("dm writecache: add event counters") Reported-by: Yu Kuai Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer Signed-off-by: Sasha Levin --- .../admin-guide/device-mapper/writecache.rst | 10 +++++----- drivers/md/dm-writecache.c | 12 +++++++++--- 2 files changed, 14 insertions(+), 8 deletions(-) diff --git a/Documentation/admin-guide/device-mapper/writecache.rst b/Documentation/admin-guide/device-mapper/writecache.rst index 7bead3b52690..6c9a2c74df8a 100644 --- a/Documentation/admin-guide/device-mapper/writecache.rst +++ b/Documentation/admin-guide/device-mapper/writecache.rst @@ -80,11 +80,11 @@ Status: 4. the number of blocks under writeback 5. the number of read blocks 6. the number of read blocks that hit the cache -7. the number of write requests -8. the number of write requests that hit uncommitted block -9. the number of write requests that hit committed block -10. the number of write requests that bypass the cache -11. the number of write requests that are allocated in the cache +7. the number of write blocks +8. the number of write blocks that hit uncommitted block +9. the number of write blocks that hit committed block +10. the number of write blocks that bypass the cache +11. the number of write blocks that are allocated in the cache 12. the number of write requests that are blocked on the freelist 13. the number of flush requests 14. the number of discard requests diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c index 3bec493cccb2..98df6327990a 100644 --- a/drivers/md/dm-writecache.c +++ b/drivers/md/dm-writecache.c @@ -1412,6 +1412,9 @@ static void writecache_bio_copy_ssd(struct dm_writecache *wc, struct bio *bio, bio->bi_iter.bi_sector = start_cache_sec; dm_accept_partial_bio(bio, bio_size >> SECTOR_SHIFT); + wc->stats.writes += bio->bi_iter.bi_size >> wc->block_size_bits; + wc->stats.writes_allocate += (bio->bi_iter.bi_size - wc->block_size) >> wc->block_size_bits; + if (unlikely(wc->uncommitted_blocks >= wc->autocommit_blocks)) { wc->uncommitted_blocks = 0; queue_work(wc->writeback_wq, &wc->flush_work); @@ -1427,9 +1430,10 @@ static enum wc_map_op writecache_map_write(struct dm_writecache *wc, struct bio do { bool found_entry = false; bool search_used = false; - wc->stats.writes++; - if (writecache_has_error(wc)) + if (writecache_has_error(wc)) { + wc->stats.writes += bio->bi_iter.bi_size >> wc->block_size_bits; return WC_MAP_ERROR; + } e = writecache_find_entry(wc, bio->bi_iter.bi_sector, 0); if (e) { if (!writecache_entry_is_committed(wc, e)) { @@ -1453,9 +1457,10 @@ static enum wc_map_op writecache_map_write(struct dm_writecache *wc, struct bio if (unlikely(!e)) { if (!WC_MODE_PMEM(wc) && !found_entry) { direct_write: - wc->stats.writes_around++; e = writecache_find_entry(wc, bio->bi_iter.bi_sector, WFE_RETURN_FOLLOWING); writecache_map_remap_origin(wc, bio, e); + wc->stats.writes_around += bio->bi_iter.bi_size >> wc->block_size_bits; + wc->stats.writes += bio->bi_iter.bi_size >> wc->block_size_bits; return WC_MAP_REMAP_ORIGIN; } wc->stats.writes_blocked_on_freelist++; @@ -1469,6 +1474,7 @@ static enum wc_map_op writecache_map_write(struct dm_writecache *wc, struct bio bio_copy: if (WC_MODE_PMEM(wc)) { bio_copy_block(wc, bio, memory_data(wc, e)); + wc->stats.writes++; } else { writecache_bio_copy_ssd(wc, bio, e, search_used); return WC_MAP_REMAP; -- 2.35.1