From patchwork Tue Mar 22 01:47:42 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Trond Myklebust X-Patchwork-Id: 12788018 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 E93A4C433EF for ; Tue, 22 Mar 2022 01:54:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235191AbiCVB4G (ORCPT ); Mon, 21 Mar 2022 21:56:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54308 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235205AbiCVB4E (ORCPT ); Mon, 21 Mar 2022 21:56:04 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E2A6612AE3 for ; Mon, 21 Mar 2022 18:54:36 -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 dfw.source.kernel.org (Postfix) with ESMTPS id 6C13360B09 for ; Tue, 22 Mar 2022 01:54:36 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 80805C340EE; Tue, 22 Mar 2022 01:54:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1647914075; bh=hQqYU8IsqDxmW6S3nbP0jML+3PV2udg3I0lI/1Lhslo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bAIAa+dNk1k1UKmdeQ6D2GN6ZGtAQsatfqSmV8/10qBx0rHlS5Q/6vTREiFp059yr razvdnQZEXe4NvXUwZ0DrGzKX2SsJGYFgr3G7OGTqzYWJDsR/kaFXr5ZWC0MesghPI NF3ki6wcX66lDJTNGHCf4DUu3+dMF0HGOdI7TVIfv8El2pqLjYdqx5VkBtfzcCrUT/ O5hWjybdZzK/e5WZardrKcl+WlmdXvT1ZsT5U0n3jr5z+BqB8Rw7sedwT9yuhYV8Py U0uEOHCWNMciQnIg7zPgQMGOepaHAYjYa6b3aC7IBKF+UySpPWj8oRgckb58VBhQM7 PjOMLJjyOqyZg== From: trondmy@kernel.org To: linux-nfs@vger.kernel.org Cc: Chuck Lever , Enrico Scholz Subject: [PATCH v2 5/9] NFS: nfsiod should not block forever in mempool_alloc() Date: Mon, 21 Mar 2022 21:47:42 -0400 Message-Id: <20220322014746.1052984-6-trondmy@kernel.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220322014746.1052984-5-trondmy@kernel.org> References: <20220322014746.1052984-1-trondmy@kernel.org> <20220322014746.1052984-2-trondmy@kernel.org> <20220322014746.1052984-3-trondmy@kernel.org> <20220322014746.1052984-4-trondmy@kernel.org> <20220322014746.1052984-5-trondmy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org From: Trond Myklebust The concern is that since nfsiod is sometimes required to kick off a commit, it can get locked up waiting forever in mempool_alloc() instead of failing gracefully and leaving the commit until later. Try to allocate from the slab first, with GFP_KERNEL | __GFP_NORETRY, then fall back to a non-blocking attempt to allocate from the memory pool. Signed-off-by: Trond Myklebust --- fs/nfs/internal.h | 7 +++++++ fs/nfs/pnfs_nfs.c | 8 ++++++-- fs/nfs/write.c | 24 +++++++++--------------- include/linux/nfs_fs.h | 2 +- 4 files changed, 23 insertions(+), 18 deletions(-) diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h index 194840a97e3a..57b0497105c8 100644 --- a/fs/nfs/internal.h +++ b/fs/nfs/internal.h @@ -587,6 +587,13 @@ nfs_write_match_verf(const struct nfs_writeverf *verf, !nfs_write_verifier_cmp(&req->wb_verf, &verf->verifier); } +static inline gfp_t nfs_io_gfp_mask(void) +{ + if (current->flags & PF_WQ_WORKER) + return GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN; + return GFP_KERNEL; +} + /* unlink.c */ extern struct rpc_task * nfs_async_rename(struct inode *old_dir, struct inode *new_dir, diff --git a/fs/nfs/pnfs_nfs.c b/fs/nfs/pnfs_nfs.c index 316f68f96e57..657c242a18ff 100644 --- a/fs/nfs/pnfs_nfs.c +++ b/fs/nfs/pnfs_nfs.c @@ -419,7 +419,7 @@ static struct nfs_commit_data * pnfs_bucket_fetch_commitdata(struct pnfs_commit_bucket *bucket, struct nfs_commit_info *cinfo) { - struct nfs_commit_data *data = nfs_commitdata_alloc(false); + struct nfs_commit_data *data = nfs_commitdata_alloc(); if (!data) return NULL; @@ -515,7 +515,11 @@ pnfs_generic_commit_pagelist(struct inode *inode, struct list_head *mds_pages, unsigned int nreq = 0; if (!list_empty(mds_pages)) { - data = nfs_commitdata_alloc(true); + data = nfs_commitdata_alloc(); + if (!data) { + nfs_retry_commit(mds_pages, NULL, cinfo, -1); + return -ENOMEM; + } data->ds_commit_index = -1; list_splice_init(mds_pages, &data->pages); list_add_tail(&data->list, &list); diff --git a/fs/nfs/write.c b/fs/nfs/write.c index 599a82406d38..ef47e3700e4b 100644 --- a/fs/nfs/write.c +++ b/fs/nfs/write.c @@ -70,27 +70,17 @@ static mempool_t *nfs_wdata_mempool; static struct kmem_cache *nfs_cdata_cachep; static mempool_t *nfs_commit_mempool; -struct nfs_commit_data *nfs_commitdata_alloc(bool never_fail) +struct nfs_commit_data *nfs_commitdata_alloc(void) { struct nfs_commit_data *p; - if (never_fail) - p = mempool_alloc(nfs_commit_mempool, GFP_NOIO); - else { - /* It is OK to do some reclaim, not no safe to wait - * for anything to be returned to the pool. - * mempool_alloc() cannot handle that particular combination, - * so we need two separate attempts. - */ + p = kmem_cache_zalloc(nfs_cdata_cachep, nfs_io_gfp_mask()); + if (!p) { p = mempool_alloc(nfs_commit_mempool, GFP_NOWAIT); - if (!p) - p = kmem_cache_alloc(nfs_cdata_cachep, GFP_NOIO | - __GFP_NOWARN | __GFP_NORETRY); if (!p) return NULL; + memset(p, 0, sizeof(*p)); } - - memset(p, 0, sizeof(*p)); INIT_LIST_HEAD(&p->pages); return p; } @@ -1826,7 +1816,11 @@ nfs_commit_list(struct inode *inode, struct list_head *head, int how, if (list_empty(head)) return 0; - data = nfs_commitdata_alloc(true); + data = nfs_commitdata_alloc(); + if (!data) { + nfs_retry_commit(head, NULL, cinfo, -1); + return -ENOMEM; + } /* Set up the argument struct */ nfs_init_commit(data, head, NULL, cinfo); diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h index c47c448befc8..db305abafc9e 100644 --- a/include/linux/nfs_fs.h +++ b/include/linux/nfs_fs.h @@ -580,7 +580,7 @@ extern int nfs_wb_all(struct inode *inode); extern int nfs_wb_page(struct inode *inode, struct page *page); extern int nfs_wb_page_cancel(struct inode *inode, struct page* page); extern int nfs_commit_inode(struct inode *, int); -extern struct nfs_commit_data *nfs_commitdata_alloc(bool never_fail); +extern struct nfs_commit_data *nfs_commitdata_alloc(void); extern void nfs_commit_free(struct nfs_commit_data *data); bool nfs_commit_end(struct nfs_mds_commit_info *cinfo);