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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 4182CC433E0 for ; Tue, 7 Jul 2020 14:39:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 22D0E2073E for ; Tue, 7 Jul 2020 14:39:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728698AbgGGOjR (ORCPT ); Tue, 7 Jul 2020 10:39:17 -0400 Received: from mx2.suse.de ([195.135.220.15]:35260 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728100AbgGGOjP (ORCPT ); Tue, 7 Jul 2020 10:39:15 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 217E9ACA7; Tue, 7 Jul 2020 14:39:14 +0000 (UTC) Subject: Re: [PATCH 13/23] btrfs: add the data transaction commit logic into may_commit_transaction To: Josef Bacik , linux-btrfs@vger.kernel.org, kernel-team@fb.com References: <20200630135921.745612-1-josef@toxicpanda.com> <20200630135921.745612-14-josef@toxicpanda.com> From: Nikolay Borisov Autocrypt: addr=nborisov@suse.com; prefer-encrypt=mutual; keydata= xsFNBFiKBz4BEADNHZmqwhuN6EAzXj9SpPpH/nSSP8YgfwoOqwrP+JR4pIqRK0AWWeWCSwmZ T7g+RbfPFlmQp+EwFWOtABXlKC54zgSf+uulGwx5JAUFVUIRBmnHOYi/lUiE0yhpnb1KCA7f u/W+DkwGerXqhhe9TvQoGwgCKNfzFPZoM+gZrm+kWv03QLUCr210n4cwaCPJ0Nr9Z3c582xc bCUVbsjt7BN0CFa2BByulrx5xD9sDAYIqfLCcZetAqsTRGxM7LD0kh5WlKzOeAXj5r8DOrU2 GdZS33uKZI/kZJZVytSmZpswDsKhnGzRN1BANGP8sC+WD4eRXajOmNh2HL4P+meO1TlM3GLl EQd2shHFY0qjEo7wxKZI1RyZZ5AgJnSmehrPCyuIyVY210CbMaIKHUIsTqRgY5GaNME24w7h TyyVCy2qAM8fLJ4Vw5bycM/u5xfWm7gyTb9V1TkZ3o1MTrEsrcqFiRrBY94Rs0oQkZvunqia c+NprYSaOG1Cta14o94eMH271Kka/reEwSZkC7T+o9hZ4zi2CcLcY0DXj0qdId7vUKSJjEep c++s8ncFekh1MPhkOgNj8pk17OAESanmDwksmzh1j12lgA5lTFPrJeRNu6/isC2zyZhTwMWs k3LkcTa8ZXxh0RfWAqgx/ogKPk4ZxOXQEZetkEyTFghbRH2BIwARAQABzSJOaWtvbGF5IEJv cmlzb3YgPG5ib3Jpc292QHN1c2UuZGU+wsF4BBMBAgAiBQJYijkSAhsDBgsJCAcDAgYVCAIJ CgsEFgIDAQIeAQIXgAAKCRBxvoJG5T8oV/B6D/9a8EcRPdHg8uLEPywuJR8URwXzkofT5bZE IfGF0Z+Lt2ADe+nLOXrwKsamhweUFAvwEUxxnndovRLPOpWerTOAl47lxad08080jXnGfYFS Dc+ew7C3SFI4tFFHln8Y22Q9075saZ2yQS1ywJy+TFPADIprAZXnPbbbNbGtJLoq0LTiESnD w/SUC6sfikYwGRS94Dc9qO4nWyEvBK3Ql8NkoY0Sjky3B0vL572Gq0ytILDDGYuZVo4alUs8 LeXS5ukoZIw1QYXVstDJQnYjFxYgoQ5uGVi4t7FsFM/6ykYDzbIPNOx49Rbh9W4uKsLVhTzG BDTzdvX4ARl9La2kCQIjjWRg+XGuBM5rxT/NaTS78PXjhqWNYlGc5OhO0l8e5DIS2tXwYMDY LuHYNkkpMFksBslldvNttSNei7xr5VwjVqW4vASk2Aak5AleXZS+xIq2FADPS/XSgIaepyTV tkfnyreep1pk09cjfXY4A7qpEFwazCRZg9LLvYVc2M2eFQHDMtXsH59nOMstXx2OtNMcx5p8 0a5FHXE/HoXz3p9bD0uIUq6p04VYOHsMasHqHPbsMAq9V2OCytJQPWwe46bBjYZCOwG0+x58 fBFreP/NiJNeTQPOa6FoxLOLXMuVtpbcXIqKQDoEte9aMpoj9L24f60G4q+pL/54ql2VRscK d87BTQRYigc+ARAAyJSq9EFk28++SLfg791xOh28tLI6Yr8wwEOvM3wKeTfTZd+caVb9gBBy wxYhIopKlK1zq2YP7ZjTP1aPJGoWvcQZ8fVFdK/1nW+Z8/NTjaOx1mfrrtTGtFxVBdSCgqBB jHTnlDYV1R5plJqK+ggEP1a0mr/rpQ9dFGvgf/5jkVpRnH6BY0aYFPprRL8ZCcdv2DeeicOO YMobD5g7g/poQzHLLeT0+y1qiLIFefNABLN06Lf0GBZC5l8hCM3Rpb4ObyQ4B9PmL/KTn2FV Xq/c0scGMdXD2QeWLePC+yLMhf1fZby1vVJ59pXGq+o7XXfYA7xX0JsTUNxVPx/MgK8aLjYW hX+TRA4bCr4uYt/S3ThDRywSX6Hr1lyp4FJBwgyb8iv42it8KvoeOsHqVbuCIGRCXqGGiaeX Wa0M/oxN1vJjMSIEVzBAPi16tztL/wQtFHJtZAdCnuzFAz8ue6GzvsyBj97pzkBVacwp3/Mw qbiu7sDz7yB0d7J2tFBJYNpVt/Lce6nQhrvon0VqiWeMHxgtQ4k92Eja9u80JDaKnHDdjdwq FUikZirB28UiLPQV6PvCckgIiukmz/5ctAfKpyYRGfez+JbAGl6iCvHYt/wAZ7Oqe/3Cirs5 KhaXBcMmJR1qo8QH8eYZ+qhFE3bSPH446+5oEw8A9v5oonKV7zMAEQEAAcLBXwQYAQIACQUC WIoHPgIbDAAKCRBxvoJG5T8oV1pyD/4zdXdOL0lhkSIjJWGqz7Idvo0wjVHSSQCbOwZDWNTN JBTP0BUxHpPu/Z8gRNNP9/k6i63T4eL1xjy4umTwJaej1X15H8Hsh+zakADyWHadbjcUXCkg OJK4NsfqhMuaIYIHbToi9K5pAKnV953xTrK6oYVyd/Rmkmb+wgsbYQJ0Ur1Ficwhp6qU1CaJ mJwFjaWaVgUERoxcejL4ruds66LM9Z1Qqgoer62ZneID6ovmzpCWbi2sfbz98+kW46aA/w8r 7sulgs1KXWhBSv5aWqKU8C4twKjlV2XsztUUsyrjHFj91j31pnHRklBgXHTD/pSRsN0UvM26 lPs0g3ryVlG5wiZ9+JbI3sKMfbdfdOeLxtL25ujs443rw1s/PVghphoeadVAKMPINeRCgoJH zZV/2Z/myWPRWWl/79amy/9MfxffZqO9rfugRBORY0ywPHLDdo9Kmzoxoxp9w3uTrTLZaT9M KIuxEcV8wcVjr+Wr9zRl06waOCkgrQbTPp631hToxo+4rA1jiQF2M80HAet65ytBVR2pFGZF zGYYLqiG+mpUZ+FPjxk9kpkRYz61mTLSY7tuFljExfJWMGfgSg1OxfLV631jV1TcdUnx+h3l Sqs2vMhAVt14zT8mpIuu2VNxcontxgVr1kzYA/tQg32fVRbGr449j1gw57BV9i0vww== Message-ID: <216b0050-3684-9c74-16e6-8a776a23f41e@suse.com> Date: Tue, 7 Jul 2020 17:39:12 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.8.0 MIME-Version: 1.0 In-Reply-To: <20200630135921.745612-14-josef@toxicpanda.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On 30.06.20 г. 16:59 ч., Josef Bacik wrote: > Data space flushing currently unconditionally commits the transaction > twice in a row, and the last time it checks if there's enough pinned > extents to satisfy it's reservation before deciding to commit the > transaction for the 3rd and final time. > > Encode this logic into may_commit_transaction(). In the next patch we > will pass in U64_MAX for bytes_needed the first two times, and the final > time we will pass in the actual bytes we need so the normal logic will > apply. > > This patch exists soley to make the logical changes I will make to the > flushing state machine separate to make it easier to bisect any > performance related regressions. > > Reviewed-by: Nikolay Borisov > Tested-by: Nikolay Borisov > Signed-off-by: Josef Bacik On a second pass through I'm now somewhat reluctant to merge this code. may_commit_transaction has grown more logic which pertain solely to metadata. As such I think we should separate that logic (i.e current may_commit_transaction) and any further adjustments we might want to make for data space info. For example all the delayed refs/trans reservation checks etc. make absolutely no sense for data space info. > --- > fs/btrfs/space-info.c | 24 +++++++++++++++++++----- > 1 file changed, 19 insertions(+), 5 deletions(-) > > diff --git a/fs/btrfs/space-info.c b/fs/btrfs/space-info.c > index e041b1d58e28..fb63ddc31540 100644 > --- a/fs/btrfs/space-info.c > +++ b/fs/btrfs/space-info.c > @@ -579,21 +579,33 @@ static void shrink_delalloc(struct btrfs_fs_info *fs_info, > * will return -ENOSPC. > */ > static int may_commit_transaction(struct btrfs_fs_info *fs_info, > - struct btrfs_space_info *space_info) > + struct btrfs_space_info *space_info, > + u64 bytes_needed) > { > struct reserve_ticket *ticket = NULL; > struct btrfs_block_rsv *delayed_rsv = &fs_info->delayed_block_rsv; > struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv; > struct btrfs_block_rsv *trans_rsv = &fs_info->trans_block_rsv; > struct btrfs_trans_handle *trans; > - u64 bytes_needed; > u64 reclaim_bytes = 0; > u64 cur_free_bytes = 0; > + bool do_commit = false; > > trans = (struct btrfs_trans_handle *)current->journal_info; > if (trans) > return -EAGAIN; > > + /* > + * If we are data and have passed in U64_MAX we just want to > + * unconditionally commit the transaction to match the previous data > + * flushing behavior. > + */ > + if ((space_info->flags & BTRFS_BLOCK_GROUP_DATA) && > + bytes_needed == U64_MAX) { > + do_commit = true; > + goto check_pinned; > + } > + > spin_lock(&space_info->lock); > cur_free_bytes = btrfs_space_info_used(space_info, true); > if (cur_free_bytes < space_info->total_bytes) > @@ -607,7 +619,7 @@ static int may_commit_transaction(struct btrfs_fs_info *fs_info, > else if (!list_empty(&space_info->tickets)) > ticket = list_first_entry(&space_info->tickets, > struct reserve_ticket, list); > - bytes_needed = (ticket) ? ticket->bytes : 0; > + bytes_needed = (ticket) ? ticket->bytes : bytes_needed; > > if (bytes_needed > cur_free_bytes) > bytes_needed -= cur_free_bytes; > @@ -618,6 +630,7 @@ static int may_commit_transaction(struct btrfs_fs_info *fs_info, > if (!bytes_needed) > return 0; > > +check_pinned: > trans = btrfs_join_transaction(fs_info->extent_root); > if (IS_ERR(trans)) > return PTR_ERR(trans); > @@ -627,7 +640,8 @@ static int may_commit_transaction(struct btrfs_fs_info *fs_info, > * we have block groups that are going to be freed, allowing us to > * possibly do a chunk allocation the next loop through. > */ > - if (test_bit(BTRFS_TRANS_HAVE_FREE_BGS, &trans->transaction->flags) || > + if (do_commit || > + test_bit(BTRFS_TRANS_HAVE_FREE_BGS, &trans->transaction->flags) || > __percpu_counter_compare(&space_info->total_bytes_pinned, > bytes_needed, > BTRFS_TOTAL_BYTES_PINNED_BATCH) >= 0) > @@ -743,7 +757,7 @@ static void flush_space(struct btrfs_fs_info *fs_info, > btrfs_wait_on_delayed_iputs(fs_info); > break; > case COMMIT_TRANS: > - ret = may_commit_transaction(fs_info, space_info); > + ret = may_commit_transaction(fs_info, space_info, num_bytes); > break; > default: > ret = -ENOSPC; >