From patchwork Wed Dec 9 13:11:43 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yafang Shao X-Patchwork-Id: 11961347 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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 30797C433FE for ; Wed, 9 Dec 2020 13:13:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0024D23B45 for ; Wed, 9 Dec 2020 13:13:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732183AbgLINND (ORCPT ); Wed, 9 Dec 2020 08:13:03 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52808 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732198AbgLINM7 (ORCPT ); Wed, 9 Dec 2020 08:12:59 -0500 Received: from mail-qv1-xf42.google.com (mail-qv1-xf42.google.com [IPv6:2607:f8b0:4864:20::f42]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C8496C061793; Wed, 9 Dec 2020 05:12:18 -0800 (PST) Received: by mail-qv1-xf42.google.com with SMTP id u16so503421qvl.7; Wed, 09 Dec 2020 05:12:18 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=m+1GohZiu08TBGb+QZ95Ht2UJWzVkthZE/EPME/oCwk=; b=rj51yJ4pm0vxwcF+F2ahaBRrWu5N5/7mCUWiErsgLKxD8HP1CFjRTNnGBQ/Ot9+Ike cDLYYLNt0oufK/d1VnbjooMbNIhWU55d/CrDf9reSRzJSdvDjwDGMT/vfGzfCF66PD0l I/RaAit5S03QshJf6V0SiPwqhB1oUiBX4Hlg0ovkEQt1CRuCvLJzgXPFkkAM55sWb4lp ASlNV+vE+Ie11pYKru/gji6+XiTAxWdxDRP3x1nD3S8HZIsCnl1Z8WDGq2W7MVIIj/Gm 32UzXQXN8BckG+HsKlqZQfDP4eDvBJSYNG1DKbr0CSloEd9QCwQ2xvVGm9Q/cF1MLCX7 uJ/Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=m+1GohZiu08TBGb+QZ95Ht2UJWzVkthZE/EPME/oCwk=; b=RgYzlnYmi3naGnmzZA/brfAF6/Canyc2lspJ7+QgvlX2TS39HiK833XMGFIxjbUSed vNsmnxG9EVCo2tRc0GkGSK+LSWk32Hca6kA5evAUmAhlWi90deIWk54y5RPq9o12jTLo qPzAAkQreII+pKquSO0XUTlLAuuZXPijhRHXgKW6vKB44aqW46z8TrHW865tWSRwbgHE oXvfACxPJnjcCywleoC741haTpiVj/WnLLiagDR1xIJqkV/2zxMk03hDzWczG3WjM+9i qxZpniC1ht1j9XkuYSWrFPQGSxHCi1NHK/f+dtyvjRLb69TMZNTV0GCVP4V0mX5OTmhd ekCQ== X-Gm-Message-State: AOAM530WBZmVEi72dfHO5iDQdIVQmSGYXGj1Iu2uA1vIDv7KybtnpmXe mFODuexT5jSZjn9LwS/VVxY= X-Google-Smtp-Source: ABdhPJzIhGJoZ6jjFWKoMOAmikn6JdBv+/oOFbVKqFEEAvTZWBDlcI+OuS3ykqtX+IQ5lL9bcBVKGg== X-Received: by 2002:a0c:ebc2:: with SMTP id k2mr3011309qvq.24.1607519538029; Wed, 09 Dec 2020 05:12:18 -0800 (PST) Received: from localhost.localdomain ([50.236.19.102]) by smtp.gmail.com with ESMTPSA id u72sm938114qka.15.2020.12.09.05.12.11 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Wed, 09 Dec 2020 05:12:17 -0800 (PST) From: Yafang Shao To: darrick.wong@oracle.com, willy@infradead.org, david@fromorbit.com, hch@infradead.org, mhocko@kernel.org, akpm@linux-foundation.org, dhowells@redhat.com, jlayton@redhat.com Cc: linux-fsdevel@vger.kernel.org, linux-cachefs@redhat.com, linux-xfs@vger.kernel.org, linux-mm@kvack.org, Michal Hocko , Christoph Hellwig , Yafang Shao Subject: [PATCH v12 1/4] mm: Add become_kswapd and restore_kswapd Date: Wed, 9 Dec 2020 21:11:43 +0800 Message-Id: <20201209131146.67289-2-laoar.shao@gmail.com> X-Mailer: git-send-email 2.24.3 (Apple Git-128) In-Reply-To: <20201209131146.67289-1-laoar.shao@gmail.com> References: <20201209131146.67289-1-laoar.shao@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org From: "Matthew Wilcox (Oracle)" Since XFS needs to pretend to be kswapd in some of its worker threads, create methods to save & restore kswapd state. Don't bother restoring kswapd state in kswapd -- the only time we reach this code is when we're exiting and the task_struct is about to be destroyed anyway. Cc: Dave Chinner Acked-by: Michal Hocko Reviewed-by: Darrick J. Wong Reviewed-by: Christoph Hellwig Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Yafang Shao --- fs/xfs/libxfs/xfs_btree.c | 14 ++++++++------ include/linux/sched/mm.h | 23 +++++++++++++++++++++++ mm/vmscan.c | 16 +--------------- 3 files changed, 32 insertions(+), 21 deletions(-) diff --git a/fs/xfs/libxfs/xfs_btree.c b/fs/xfs/libxfs/xfs_btree.c index 2d25bab68764..a04a44238aab 100644 --- a/fs/xfs/libxfs/xfs_btree.c +++ b/fs/xfs/libxfs/xfs_btree.c @@ -2813,8 +2813,9 @@ xfs_btree_split_worker( { struct xfs_btree_split_args *args = container_of(work, struct xfs_btree_split_args, work); + bool is_kswapd = args->kswapd; unsigned long pflags; - unsigned long new_pflags = PF_MEMALLOC_NOFS; + int memalloc_nofs; /* * we are in a transaction context here, but may also be doing work @@ -2822,16 +2823,17 @@ xfs_btree_split_worker( * temporarily to ensure that we don't block waiting for memory reclaim * in any way. */ - if (args->kswapd) - new_pflags |= PF_MEMALLOC | PF_SWAPWRITE | PF_KSWAPD; - - current_set_flags_nested(&pflags, new_pflags); + if (is_kswapd) + pflags = become_kswapd(); + memalloc_nofs = memalloc_nofs_save(); args->result = __xfs_btree_split(args->cur, args->level, args->ptrp, args->key, args->curp, args->stat); complete(args->done); - current_restore_flags_nested(&pflags, new_pflags); + memalloc_nofs_restore(memalloc_nofs); + if (is_kswapd) + restore_kswapd(pflags); } /* diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h index d5ece7a9a403..2faf03e79a1e 100644 --- a/include/linux/sched/mm.h +++ b/include/linux/sched/mm.h @@ -278,6 +278,29 @@ static inline void memalloc_nocma_restore(unsigned int flags) } #endif +/* + * Tell the memory management code that this thread is working on behalf + * of background memory reclaim (like kswapd). That means that it will + * get access to memory reserves should it need to allocate memory in + * order to make forward progress. With this great power comes great + * responsibility to not exhaust those reserves. + */ +#define KSWAPD_PF_FLAGS (PF_MEMALLOC | PF_SWAPWRITE | PF_KSWAPD) + +static inline unsigned long become_kswapd(void) +{ + unsigned long flags = current->flags & KSWAPD_PF_FLAGS; + + current->flags |= KSWAPD_PF_FLAGS; + + return flags; +} + +static inline void restore_kswapd(unsigned long flags) +{ + current->flags &= ~(flags ^ KSWAPD_PF_FLAGS); +} + #ifdef CONFIG_MEMCG DECLARE_PER_CPU(struct mem_cgroup *, int_active_memcg); /** diff --git a/mm/vmscan.c b/mm/vmscan.c index 1b8f0e059767..77bc1dda75bf 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -3869,19 +3869,7 @@ static int kswapd(void *p) if (!cpumask_empty(cpumask)) set_cpus_allowed_ptr(tsk, cpumask); - /* - * Tell the memory management that we're a "memory allocator", - * and that if we need more memory we should get access to it - * regardless (see "__alloc_pages()"). "kswapd" should - * never get caught in the normal page freeing logic. - * - * (Kswapd normally doesn't need memory anyway, but sometimes - * you need a small amount of memory in order to be able to - * page out something else, and this flag essentially protects - * us from recursively trying to free more memory as we're - * trying to free the first piece of memory in the first place). - */ - tsk->flags |= PF_MEMALLOC | PF_SWAPWRITE | PF_KSWAPD; + become_kswapd(); set_freezable(); WRITE_ONCE(pgdat->kswapd_order, 0); @@ -3931,8 +3919,6 @@ static int kswapd(void *p) goto kswapd_try_sleep; } - tsk->flags &= ~(PF_MEMALLOC | PF_SWAPWRITE | PF_KSWAPD); - return 0; } From patchwork Wed Dec 9 13:11:44 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yafang Shao X-Patchwork-Id: 11961351 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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 7926CC433FE for ; Wed, 9 Dec 2020 13:13:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5284C23BC7 for ; Wed, 9 Dec 2020 13:13:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732166AbgLINNU (ORCPT ); Wed, 9 Dec 2020 08:13:20 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52830 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729181AbgLINNH (ORCPT ); Wed, 9 Dec 2020 08:13:07 -0500 Received: from mail-qt1-x842.google.com (mail-qt1-x842.google.com [IPv6:2607:f8b0:4864:20::842]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1F2DDC061794; Wed, 9 Dec 2020 05:12:27 -0800 (PST) Received: by mail-qt1-x842.google.com with SMTP id z3so807640qtw.9; Wed, 09 Dec 2020 05:12:27 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=iBZKS7fZyjdTYTaO3rtutG8028bfWaEOmNu0KLWmO18=; b=HsxN5ATN5b8eLKXY4ZeibMTxltQSgGAeusNM1yE9jrmciX19XFhHuP6b8i+KYmQ7RA 8i78cmkmxPwzPYRbL5jkQ3KA7RXrQJN4V5N4OwXQjmb+0t0RJXbDP2OlQI8hctib0CGh iG7lMvmjJ0zsDyuqROWpQws07Q0ZpoBOwd6ZgIT+8ChDIVchr2s/9GBhK7xwICRS6xe2 bXq/h2nyxJc4y80zJnXc4zxqK492XYFV74pvyWTUknrfncjKW/WIqUfoQJ1SWampGOWI 64p+yPxtiYDVGmdww+sT46Mza8xf0Pc2xVnpuEM4oSVTfLIiYWgx8uI63mTb2CCM8S0l Jd2w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=iBZKS7fZyjdTYTaO3rtutG8028bfWaEOmNu0KLWmO18=; b=RUM8SpFK32atm6FLyIQcR15UIVfWMUQBE7B7crC6Nv9CH8aBvxJg2OwUvm1XYQfWrs QlrcQ/sXqXxJ6Cj8XfifTalSpb40fkUx8MvkoPD9VOk5HvhrA7Cb14rNv2mso4vTbs5B nTS+xQ05hcMqBKRJRQrdrW6g+Rhic8qPMUoRpyVNyu/39ViW3tkzdJGHPcCR32V9yJD8 sfDuAiYbyVV2Bl1APFWRLwuhWDFI/Z0MN8RUPDDfnSf3JXqDUoRR6CfaqjpLgy8L96IL WeFPTgWCWJU1p7YGUnTkKdNzySw8K81iXumivGZ6GXvAQzcNXIMgq1hnSnW999glYt8P R/ug== X-Gm-Message-State: AOAM531U/ua43eaUhnmF+lOU2ecjTGmwpdE23rvELgThPLZleBYSdagb WKIhZ/TVQiO/v9cj0jfaIEjxum0tzXXQpw== X-Google-Smtp-Source: ABdhPJwwOCvQR3EmCa5QLZLnDJYam2cyyD1uwIzB+gbjBFnQ/bKUFYsFwLrllWPQx5I4SJCh6tS2eQ== X-Received: by 2002:ac8:2bd2:: with SMTP id n18mr3081861qtn.260.1607519544946; Wed, 09 Dec 2020 05:12:24 -0800 (PST) Received: from localhost.localdomain ([50.236.19.102]) by smtp.gmail.com with ESMTPSA id u72sm938114qka.15.2020.12.09.05.12.18 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Wed, 09 Dec 2020 05:12:23 -0800 (PST) From: Yafang Shao To: darrick.wong@oracle.com, willy@infradead.org, david@fromorbit.com, hch@infradead.org, mhocko@kernel.org, akpm@linux-foundation.org, dhowells@redhat.com, jlayton@redhat.com Cc: linux-fsdevel@vger.kernel.org, linux-cachefs@redhat.com, linux-xfs@vger.kernel.org, linux-mm@kvack.org, Yafang Shao , Christoph Hellwig Subject: [PATCH v12 2/4] xfs: use memalloc_nofs_{save,restore} in xfs transaction Date: Wed, 9 Dec 2020 21:11:44 +0800 Message-Id: <20201209131146.67289-3-laoar.shao@gmail.com> X-Mailer: git-send-email 2.24.3 (Apple Git-128) In-Reply-To: <20201209131146.67289-1-laoar.shao@gmail.com> References: <20201209131146.67289-1-laoar.shao@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org Introduce a new API to mark the start and end of XFS transactions. For now, just save and restore the memalloc_nofs flags. The new helpers as follows, - xfs_trans_context_set Mark the start of XFS transactions - xfs_trans_context_clear Mark the end of XFS transactions Cc: Matthew Wilcox (Oracle) Cc: Christoph Hellwig Cc: Dave Chinner Cc: Michal Hocko Reviewed-by: Darrick J. Wong Signed-off-by: Yafang Shao --- fs/xfs/xfs_aops.c | 4 ++-- fs/xfs/xfs_linux.h | 4 ---- fs/xfs/xfs_trans.c | 13 +++++++------ fs/xfs/xfs_trans.h | 12 ++++++++++++ 4 files changed, 21 insertions(+), 12 deletions(-) diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c index 4304c6416fbb..2371187b7615 100644 --- a/fs/xfs/xfs_aops.c +++ b/fs/xfs/xfs_aops.c @@ -62,7 +62,7 @@ xfs_setfilesize_trans_alloc( * We hand off the transaction to the completion thread now, so * clear the flag here. */ - current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS); + xfs_trans_context_clear(tp); return 0; } @@ -125,7 +125,7 @@ xfs_setfilesize_ioend( * thus we need to mark ourselves as being in a transaction manually. * Similarly for freeze protection. */ - current_set_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS); + xfs_trans_context_set(tp); __sb_writers_acquired(VFS_I(ip)->i_sb, SB_FREEZE_FS); /* we abort the update if there was an IO error */ diff --git a/fs/xfs/xfs_linux.h b/fs/xfs/xfs_linux.h index 5b7a1e201559..6ab0f8043c73 100644 --- a/fs/xfs/xfs_linux.h +++ b/fs/xfs/xfs_linux.h @@ -102,10 +102,6 @@ typedef __u32 xfs_nlink_t; #define xfs_cowb_secs xfs_params.cowb_timer.val #define current_cpu() (raw_smp_processor_id()) -#define current_set_flags_nested(sp, f) \ - (*(sp) = current->flags, current->flags |= (f)) -#define current_restore_flags_nested(sp, f) \ - (current->flags = ((current->flags & ~(f)) | (*(sp) & (f)))) #define NBBY 8 /* number of bits per byte */ diff --git a/fs/xfs/xfs_trans.c b/fs/xfs/xfs_trans.c index c94e71f741b6..11d390f0d3f2 100644 --- a/fs/xfs/xfs_trans.c +++ b/fs/xfs/xfs_trans.c @@ -154,7 +154,7 @@ xfs_trans_reserve( bool rsvd = (tp->t_flags & XFS_TRANS_RESERVE) != 0; /* Mark this thread as being in a transaction */ - current_set_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS); + xfs_trans_context_set(tp); /* * Attempt to reserve the needed disk blocks by decrementing @@ -164,7 +164,7 @@ xfs_trans_reserve( if (blocks > 0) { error = xfs_mod_fdblocks(mp, -((int64_t)blocks), rsvd); if (error != 0) { - current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS); + xfs_trans_context_clear(tp); return -ENOSPC; } tp->t_blk_res += blocks; @@ -241,7 +241,7 @@ xfs_trans_reserve( tp->t_blk_res = 0; } - current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS); + xfs_trans_context_clear(tp); return error; } @@ -878,7 +878,7 @@ __xfs_trans_commit( xfs_log_commit_cil(mp, tp, &commit_lsn, regrant); - current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS); + xfs_trans_context_clear(tp); xfs_trans_free(tp); /* @@ -910,7 +910,8 @@ __xfs_trans_commit( xfs_log_ticket_ungrant(mp->m_log, tp->t_ticket); tp->t_ticket = NULL; } - current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS); + + xfs_trans_context_clear(tp); xfs_trans_free_items(tp, !!error); xfs_trans_free(tp); @@ -971,7 +972,7 @@ xfs_trans_cancel( } /* mark this thread as no longer being in a transaction */ - current_restore_flags_nested(&tp->t_pflags, PF_MEMALLOC_NOFS); + xfs_trans_context_clear(tp); xfs_trans_free_items(tp, dirty); xfs_trans_free(tp); diff --git a/fs/xfs/xfs_trans.h b/fs/xfs/xfs_trans.h index 084658946cc8..44b11c64a15e 100644 --- a/fs/xfs/xfs_trans.h +++ b/fs/xfs/xfs_trans.h @@ -268,4 +268,16 @@ xfs_trans_item_relog( return lip->li_ops->iop_relog(lip, tp); } +static inline void +xfs_trans_context_set(struct xfs_trans *tp) +{ + tp->t_pflags = memalloc_nofs_save(); +} + +static inline void +xfs_trans_context_clear(struct xfs_trans *tp) +{ + memalloc_nofs_restore(tp->t_pflags); +} + #endif /* __XFS_TRANS_H__ */ From patchwork Wed Dec 9 13:11:45 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yafang Shao X-Patchwork-Id: 11961349 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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 1AAD7C4361B for ; Wed, 9 Dec 2020 13:13:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E016E23BC7 for ; Wed, 9 Dec 2020 13:13:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731958AbgLINNU (ORCPT ); Wed, 9 Dec 2020 08:13:20 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52846 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732166AbgLINNM (ORCPT ); Wed, 9 Dec 2020 08:13:12 -0500 Received: from mail-qk1-x744.google.com (mail-qk1-x744.google.com [IPv6:2607:f8b0:4864:20::744]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D3B80C06179C; Wed, 9 Dec 2020 05:12:31 -0800 (PST) Received: by mail-qk1-x744.google.com with SMTP id c7so1100899qke.1; Wed, 09 Dec 2020 05:12:31 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=U/1xqfI5qUo3gDO+06cA0eClvvlW5lp3NGGPYOZ6sWg=; b=qsxmL+1cQe00msicjBwK/HwlXWZBf7gT2pnAsOYkUDq77RjLamhFzAW0B0ceSk6Vi3 AOPfASgjN8kTjwnBxQijmYZh/kDmttxjj1TrNK0HPm4Rr3xPtcNqwRq/zRyjoatPtcn0 Mpft7TA6nZOBZe4owiGB90EKNoA2jwgb8v3otQbZm91LETiyUFMrlUFmsOFQpr16nL85 OqyvHkUZjb7TpzHAI/FNYQCqPPGfViRt+za0XCzXfjMVF86nwOhf/CcSAOkwtWQwmyzX Uk7YxYSpynGnXKqhBXS19hrL3Keijw19VALRdQoljFvcw136cunMyLvsbokCZ7odw+B6 8ylw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=U/1xqfI5qUo3gDO+06cA0eClvvlW5lp3NGGPYOZ6sWg=; b=jLivbb9q6IHskEaUAEw1T7qL7lI/3LNEpNd9EiBkoGzfHrBjd70Uq1YwI3gJm7Eqia 4Ugfrk0Qco070RdjQhmjHC8tPgZ/af2V9XidllwxB6aG58K+u2401jI0TREWqlsypOFA kvrbqY+1cu5+8ug+HXJDnQxYAbPHdbYruVN9XKkd2ueVzDRFalmcUF6LtzFMGbkpE2A8 1XGqlJCYfPnOzmPGG5bO6pfb6leT/ymptc2jd/6YGzbDUL1qJ36PMG4s7yoM7i2nYAiT Ox3NmPYsexRqDbuSHweOSk0VXHKfsUU/Zax9ZW6KHwCkzKpgt2o12TxvNz9cI+LPVum7 sejA== X-Gm-Message-State: AOAM531Iul7UBQZPXU6vBvBx/8OJSnE0XvVviKxBvSC8WkK5Z6WSneOX Lowc1Co5vDaacfxIlWc+DNg= X-Google-Smtp-Source: ABdhPJxB0/jAlENo3tmNLdMytrMRXbSsuKgW8S6j4ULYI9Bw/bihb/0tXNXtJPrr5KbOt6cyGOqcXA== X-Received: by 2002:a05:620a:2290:: with SMTP id o16mr2832688qkh.101.1607519551095; Wed, 09 Dec 2020 05:12:31 -0800 (PST) Received: from localhost.localdomain ([50.236.19.102]) by smtp.gmail.com with ESMTPSA id u72sm938114qka.15.2020.12.09.05.12.25 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Wed, 09 Dec 2020 05:12:30 -0800 (PST) From: Yafang Shao To: darrick.wong@oracle.com, willy@infradead.org, david@fromorbit.com, hch@infradead.org, mhocko@kernel.org, akpm@linux-foundation.org, dhowells@redhat.com, jlayton@redhat.com Cc: linux-fsdevel@vger.kernel.org, linux-cachefs@redhat.com, linux-xfs@vger.kernel.org, linux-mm@kvack.org, Yafang Shao , Christoph Hellwig Subject: [PATCH v12 3/4] xfs: refactor the usage around xfs_trans_context_{set,clear} Date: Wed, 9 Dec 2020 21:11:45 +0800 Message-Id: <20201209131146.67289-4-laoar.shao@gmail.com> X-Mailer: git-send-email 2.24.3 (Apple Git-128) In-Reply-To: <20201209131146.67289-1-laoar.shao@gmail.com> References: <20201209131146.67289-1-laoar.shao@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org The xfs_trans context should be active after it is allocated, and deactive when it is freed. So these two helpers are refactored as, - xfs_trans_context_set() Used in xfs_trans_alloc() - xfs_trans_context_clear() Used in xfs_trans_free() This patch is based on Darrick's work to fix the issue in xfs/141 in the earlier version. [1] 1. https://lore.kernel.org/linux-xfs/20201104001649.GN7123@magnolia Cc: Darrick J. Wong Cc: Matthew Wilcox (Oracle) Cc: Christoph Hellwig Cc: Dave Chinner Signed-off-by: Yafang Shao --- fs/xfs/xfs_trans.c | 28 +++++++++++++++------------- 1 file changed, 15 insertions(+), 13 deletions(-) diff --git a/fs/xfs/xfs_trans.c b/fs/xfs/xfs_trans.c index 11d390f0d3f2..4f4645329bb2 100644 --- a/fs/xfs/xfs_trans.c +++ b/fs/xfs/xfs_trans.c @@ -67,6 +67,17 @@ xfs_trans_free( xfs_extent_busy_sort(&tp->t_busy); xfs_extent_busy_clear(tp->t_mountp, &tp->t_busy, false); + + /* Detach the transaction from this thread. */ + ASSERT(current->journal_info != NULL); + /* + * The PF_MEMALLOC_NOFS is bound to the transaction itself instead + * of the reservation, so we need to check if tp is still the + * current transaction before clearing the flag. + */ + if (current->journal_info == tp) + xfs_trans_context_clear(tp); + trace_xfs_trans_free(tp, _RET_IP_); if (!(tp->t_flags & XFS_TRANS_NO_WRITECOUNT)) sb_end_intwrite(tp->t_mountp->m_super); @@ -153,9 +164,6 @@ xfs_trans_reserve( int error = 0; bool rsvd = (tp->t_flags & XFS_TRANS_RESERVE) != 0; - /* Mark this thread as being in a transaction */ - xfs_trans_context_set(tp); - /* * Attempt to reserve the needed disk blocks by decrementing * the number needed from the number available. This will @@ -163,10 +171,9 @@ xfs_trans_reserve( */ if (blocks > 0) { error = xfs_mod_fdblocks(mp, -((int64_t)blocks), rsvd); - if (error != 0) { - xfs_trans_context_clear(tp); + if (error != 0) return -ENOSPC; - } + tp->t_blk_res += blocks; } @@ -241,8 +248,6 @@ xfs_trans_reserve( tp->t_blk_res = 0; } - xfs_trans_context_clear(tp); - return error; } @@ -284,6 +289,8 @@ xfs_trans_alloc( INIT_LIST_HEAD(&tp->t_dfops); tp->t_firstblock = NULLFSBLOCK; + /* Mark this thread as being in a transaction */ + xfs_trans_context_set(tp); error = xfs_trans_reserve(tp, resp, blocks, rtextents); if (error) { xfs_trans_cancel(tp); @@ -878,7 +885,6 @@ __xfs_trans_commit( xfs_log_commit_cil(mp, tp, &commit_lsn, regrant); - xfs_trans_context_clear(tp); xfs_trans_free(tp); /* @@ -911,7 +917,6 @@ __xfs_trans_commit( tp->t_ticket = NULL; } - xfs_trans_context_clear(tp); xfs_trans_free_items(tp, !!error); xfs_trans_free(tp); @@ -971,9 +976,6 @@ xfs_trans_cancel( tp->t_ticket = NULL; } - /* mark this thread as no longer being in a transaction */ - xfs_trans_context_clear(tp); - xfs_trans_free_items(tp, dirty); xfs_trans_free(tp); } From patchwork Wed Dec 9 13:11:46 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yafang Shao X-Patchwork-Id: 11961353 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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 25D5EC4167B for ; Wed, 9 Dec 2020 13:15:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E59AE224D1 for ; Wed, 9 Dec 2020 13:15:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732246AbgLINNc (ORCPT ); Wed, 9 Dec 2020 08:13:32 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52884 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729181AbgLINN0 (ORCPT ); Wed, 9 Dec 2020 08:13:26 -0500 Received: from mail-qk1-x742.google.com (mail-qk1-x742.google.com [IPv6:2607:f8b0:4864:20::742]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C8D4FC0617A6; Wed, 9 Dec 2020 05:12:37 -0800 (PST) Received: by mail-qk1-x742.google.com with SMTP id d14so415605qkc.13; Wed, 09 Dec 2020 05:12:37 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=Vo2hMZxAvlst2gwI48xlPnEAZTs7fn2tgVy4jkvkfak=; b=rA0uPedR6iMFDORqVibYIouE2sHlfBsLJl/kDe5KAyEAiHd/5lBoupnyE10Vk+5LPp fO01gbxW8xbv1FBkrvWBN1BtDVW1kS2tD8sTUeV0lwDNYEbHVGF0NYDMtZv+0T0Km9ZA /u7b/RQh7hCku29/FDMiRYzfjCp1IpWsu8tUf2zFYw21T59oj0Ke78GOTuAOQdpcrugq tt5gPAz5wwdiQWbFSGiBgYmXw5GX1SwqR1dY7OX1bOZjE2ZBOc929vIRTMPQfyWI7p/j /j0ajn4wLxea+xgZyyNTsRqR6tsXIKqS4R0QHYhpacoGraXbMeEqS43YUyPSw6Tk08aF mE5w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=Vo2hMZxAvlst2gwI48xlPnEAZTs7fn2tgVy4jkvkfak=; b=I3s0wFyIYq6Fki+MEZboppm7svGFHZqTAVbqAGOMUNlONJLsWM05GsrfRWnIBKGjoN q+nJnHmF8GHjhLhfhxmEgaJKX+MYD63kODAptL0VePj7N8Q8SJjOQyOoNpdBPH74hX5d p6Im2mOpig3N1QfKBG+FbJIC6v7hS5gsFYcIJ6KdN7aKKkki3oMn5ck2LvJf6UfLVVSc T2saIOBKegyfHgWE+B5F5/hqgdnxfy7SiqXFljviuorQfM9YmwEUUCtGgu+vvTMI1KOD zBVvJqEEcqc2tHawmOm2+jdn0EorSCcPicrTMtvMjUP1/cLgdxlTN6muxLU3mZx+6aj+ rpRQ== X-Gm-Message-State: AOAM531ofzAVz+mUtU8ZDEs0a+Yz0aW6oRAJ/OHNyRQ3OefUJ5qaCz4Z KMow81+btRGW9ymHKIpKd2c= X-Google-Smtp-Source: ABdhPJzE8FiJCH3XNPdUh271c8izjZ1PbF4C+rKvyzEFeqiYiRR5QcVOZ62jupL5NknQ1sFGJAj5tw== X-Received: by 2002:a37:8384:: with SMTP id f126mr2848840qkd.500.1607519557106; Wed, 09 Dec 2020 05:12:37 -0800 (PST) Received: from localhost.localdomain ([50.236.19.102]) by smtp.gmail.com with ESMTPSA id u72sm938114qka.15.2020.12.09.05.12.31 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Wed, 09 Dec 2020 05:12:36 -0800 (PST) From: Yafang Shao To: darrick.wong@oracle.com, willy@infradead.org, david@fromorbit.com, hch@infradead.org, mhocko@kernel.org, akpm@linux-foundation.org, dhowells@redhat.com, jlayton@redhat.com Cc: linux-fsdevel@vger.kernel.org, linux-cachefs@redhat.com, linux-xfs@vger.kernel.org, linux-mm@kvack.org, Yafang Shao , Christoph Hellwig Subject: [PATCH v12 4/4] xfs: use current->journal_info to avoid transaction reservation recursion Date: Wed, 9 Dec 2020 21:11:46 +0800 Message-Id: <20201209131146.67289-5-laoar.shao@gmail.com> X-Mailer: git-send-email 2.24.3 (Apple Git-128) In-Reply-To: <20201209131146.67289-1-laoar.shao@gmail.com> References: <20201209131146.67289-1-laoar.shao@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org PF_FSTRANS which is used to avoid transaction reservation recursion, is dropped since commit 9070733b4efa ("xfs: abstract PF_FSTRANS to PF_MEMALLOC_NOFS") and commit 7dea19f9ee63 ("mm: introduce memalloc_nofs_{save,restore} API") and replaced by PF_MEMALLOC_NOFS which means to avoid filesystem reclaim recursion. As these two flags have different meanings, we'd better reintroduce PF_FSTRANS back. To avoid wasting the space of PF_* flags in task_struct, we can reuse the current->journal_info to do that, per Willy. As the check of transaction reservation recursion is used by XFS only, we can move the check into xfs_vm_writepage(s), per Dave. To better abstract that behavoir, two new helpers are introduced, as follows, - xfs_trans_context_active To check whehter current is in fs transcation or not - xfs_trans_context_swap Transfer the transaction context when rolling a permanent transaction These two new helpers are instroduced in xfs_trans.h. Cc: Darrick J. Wong Cc: Matthew Wilcox (Oracle) Cc: Christoph Hellwig Cc: Dave Chinner Cc: Michal Hocko Cc: David Howells Cc: Jeff Layton Signed-off-by: Yafang Shao --- fs/iomap/buffered-io.c | 7 ------- fs/xfs/xfs_aops.c | 17 +++++++++++++++++ fs/xfs/xfs_trans.c | 4 +++- fs/xfs/xfs_trans.h | 23 +++++++++++++++++++++++ 4 files changed, 43 insertions(+), 8 deletions(-) diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index 10cc7979ce38..3c53fa6ce64d 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -1458,13 +1458,6 @@ iomap_do_writepage(struct page *page, struct writeback_control *wbc, void *data) PF_MEMALLOC)) goto redirty; - /* - * Given that we do not allow direct reclaim to call us, we should - * never be called in a recursive filesystem reclaim context. - */ - if (WARN_ON_ONCE(current->flags & PF_MEMALLOC_NOFS)) - goto redirty; - /* * Is this page beyond the end of the file? * diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c index 2371187b7615..0da0242d42c3 100644 --- a/fs/xfs/xfs_aops.c +++ b/fs/xfs/xfs_aops.c @@ -568,6 +568,16 @@ xfs_vm_writepage( { struct xfs_writepage_ctx wpc = { }; + /* + * Given that we do not allow direct reclaim to call us, we should + * never be called while in a filesystem transaction. + */ + if (WARN_ON_ONCE(xfs_trans_context_active())) { + redirty_page_for_writepage(wbc, page); + unlock_page(page); + return 0; + } + return iomap_writepage(page, wbc, &wpc.ctx, &xfs_writeback_ops); } @@ -579,6 +589,13 @@ xfs_vm_writepages( struct xfs_writepage_ctx wpc = { }; xfs_iflags_clear(XFS_I(mapping->host), XFS_ITRUNCATED); + /* + * Given that we do not allow direct reclaim to call us, we should + * never be called while in a filesystem transaction. + */ + if (WARN_ON_ONCE(xfs_trans_context_active())) + return 0; + return iomap_writepages(mapping, wbc, &wpc.ctx, &xfs_writeback_ops); } diff --git a/fs/xfs/xfs_trans.c b/fs/xfs/xfs_trans.c index 4f4645329bb2..7793391fe536 100644 --- a/fs/xfs/xfs_trans.c +++ b/fs/xfs/xfs_trans.c @@ -130,7 +130,9 @@ xfs_trans_dup( ntp->t_rtx_res = tp->t_rtx_res - tp->t_rtx_res_used; tp->t_rtx_res = tp->t_rtx_res_used; - ntp->t_pflags = tp->t_pflags; + + /* Associate the new transaction with this thread. */ + xfs_trans_context_swap(tp, ntp); /* move deferred ops over to the new tp */ xfs_defer_move(ntp, tp); diff --git a/fs/xfs/xfs_trans.h b/fs/xfs/xfs_trans.h index 44b11c64a15e..e994b01eeb57 100644 --- a/fs/xfs/xfs_trans.h +++ b/fs/xfs/xfs_trans.h @@ -268,16 +268,39 @@ xfs_trans_item_relog( return lip->li_ops->iop_relog(lip, tp); } +static inline bool +xfs_trans_context_active(void) +{ + /* Use journal_info to indicate current is in a transaction */ + return current->journal_info != NULL; +} + static inline void xfs_trans_context_set(struct xfs_trans *tp) { + ASSERT(!current->journal_info); + current->journal_info = tp; tp->t_pflags = memalloc_nofs_save(); } static inline void xfs_trans_context_clear(struct xfs_trans *tp) { + ASSERT(current->journal_info == tp); + current->journal_info = NULL; memalloc_nofs_restore(tp->t_pflags); } +/* + * Transfer the transaction context when rolling a permanent + * transaction. + */ +static inline void +xfs_trans_context_swap(struct xfs_trans *tp, struct xfs_trans *ntp) +{ + ASSERT(current->journal_info == tp); + ntp->t_pflags = tp->t_pflags; + current->journal_info = ntp; +} + #endif /* __XFS_TRANS_H__ */