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=-5.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 6F5A1C43381 for ; Thu, 4 Mar 2021 00:29:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 471B364E62 for ; Thu, 4 Mar 2021 00:29:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1355499AbhCDA3M (ORCPT ); Wed, 3 Mar 2021 19:29:12 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:34980 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1359133AbhCCNhp (ORCPT ); Wed, 3 Mar 2021 08:37:45 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1614778578; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type; bh=PRG44pYOCT8TBuixfsoZweOhMZzKh2b+QdLc11VmY6o=; b=J7ei76A7Y2zGCOinSMXs9Owlxntn5Tm9eOaCi0+FsUuNEoBZYM7JwzLvTJVn4rX9Jplyxz THvOOHyK/PyKZa+FDNrJiK21+FU1pbKGmLcwOqkQKSy4uvJAguDxQ0xcVvctnApzk+KXaa ubK0kg0hSjQtrbHIAeqihkUAoejYnvM= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-312-nyI7YDtsPpeonvCD7AgOCQ-1; Wed, 03 Mar 2021 08:10:44 -0500 X-MC-Unique: nyI7YDtsPpeonvCD7AgOCQ-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 2A2408017FF; Wed, 3 Mar 2021 13:10:43 +0000 (UTC) Received: from [172.16.176.1] (ovpn-64-2.rdu2.redhat.com [10.10.64.2]) by smtp.corp.redhat.com (Postfix) with ESMTPS id DA15E5D705; Wed, 3 Mar 2021 13:10:42 +0000 (UTC) From: "Benjamin Coddington" To: "Trond Myklebust" Cc: "Linux NFS Mailing List" Subject: memalloc_nofs_save() only on async Date: Wed, 03 Mar 2021 08:10:41 -0500 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; format=flowed X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org Hi Trond, I'd like to go back to setting sk->sk_allocation = GFP_NOIO (see a1231fda7e94). That would cover sync tasks as well as async, but I'm not sure what memalloc_nofs_save/restore gives us and if we should just try to apply that to all tasks. We're getting some folks deadlocked on the xprt_sending queue with stacks like: #0 [ffffacab45f17108] __schedule at ffffffffae4d1826 #1 [ffffacab45f171a0] schedule at ffffffffae4d1cb8 #2 [ffffacab45f171b0] rpc_wait_bit_killable at ffffffffc067d44e [sunrpc] #3 [ffffacab45f171c8] __wait_on_bit at ffffffffae4d216c #4 [ffffacab45f17200] out_of_line_wait_on_bit at ffffffffae4d2211 #5 [ffffacab45f17250] __rpc_execute at ffffffffc067f3fc [sunrpc] #6 [ffffacab45f172a8] rpc_run_task at ffffffffc06732c4 [sunrpc] #7 [ffffacab45f172e8] nfs4_proc_layoutreturn at ffffffffc08f5d44 [nfsv4] #8 [ffffacab45f17388] pnfs_send_layoutreturn at ffffffffc091946e [nfsv4] #9 [ffffacab45f173d8] _pnfs_return_layout at ffffffffc091ba8b [nfsv4] #10 [ffffacab45f17450] nfs4_evict_inode at ffffffffc0906a05 [nfsv4] #11 [ffffacab45f17460] evict at ffffffffadef8592 #12 [ffffacab45f17480] dispose_list at ffffffffadef86a8 #13 [ffffacab45f174a0] prune_icache_sb at ffffffffadef99a2 #14 [ffffacab45f174c8] super_cache_scan at ffffffffadede183 #15 [ffffacab45f17518] do_shrink_slab at ffffffffade3d5d8 #16 [ffffacab45f17588] shrink_slab at ffffffffade3dab5 #17 [ffffacab45f17608] shrink_node at ffffffffade42a8c #18 [ffffacab45f17678] do_try_to_free_pages at ffffffffade42e43 #19 [ffffacab45f176c8] try_to_free_pages at ffffffffade431c8 #20 [ffffacab45f17768] __alloc_pages_slowpath at ffffffffade81981 #21 [ffffacab45f17868] __alloc_pages_nodemask at ffffffffade82555 #22 [ffffacab45f178c8] skb_page_frag_refill at ffffffffae31bea7 #23 [ffffacab45f178e0] sk_page_frag_refill at ffffffffae31c71d #24 [ffffacab45f178f8] tcp_sendmsg_locked at ffffffffae3cbe65 #25 [ffffacab45f179a0] tcp_sendmsg at ffffffffae3cc8f7 #26 [ffffacab45f179c0] sock_sendmsg at ffffffffae317cce #27 [ffffacab45f179d8] xs_sendpages at ffffffffc0679741 [sunrpc] #28 [ffffacab45f17ac8] xs_tcp_send_request at ffffffffc067adb4 [sunrpc] #29 [ffffacab45f17b20] xprt_transmit at ffffffffc067674c [sunrpc] #30 [ffffacab45f17b90] call_transmit at ffffffffc0672064 [sunrpc] #31 [ffffacab45f17ba0] __rpc_execute at ffffffffc067f365 [sunrpc] #32 [ffffacab45f17bf8] rpc_run_task at ffffffffc06732c4 [sunrpc] #33 [ffffacab45f17c38] nfs4_call_sync_custom at ffffffffc08e50bb [nfsv4] #34 [ffffacab45f17c48] nfs4_call_sync_sequence at ffffffffc08e5143 [nfsv4] #35 [ffffacab45f17cb8] _nfs4_proc_getattr at ffffffffc08e7f08 [nfsv4] #36 [ffffacab45f17d78] nfs4_proc_getattr at ffffffffc08f200a [nfsv4] #37 [ffffacab45f17de8] __nfs_revalidate_inode at ffffffffc08741d7 [nfs] #38 [ffffacab45f17e18] nfs_getattr at ffffffffc0874458 [nfs] #39 [ffffacab45f17e60] vfs_statx_fd at ffffffffadedf8a4 #40 [ffffacab45f17e98] __do_sys_newfstat at ffffffffadedfedd #41 [ffffacab45f17f38] do_syscall_64 at ffffffffadc0419b #42 [ffffacab45f17f50] entry_SYSCALL_64_after_hwframe at ffffffffae6000ad RIP: 00007f721ddcdd37 RSP: 00007ffc0d54cab8 RFLAGS: 00000246 RAX: ffffffffffffffda RBX: 00007f721e09b3c0 RCX: 00007f721ddcdd37 RDX: 00007ffc0d54cac0 RSI: 00007ffc0d54cac0 RDI: 0000000000000001 RBP: 00007f721e09f6c0 R8: 00007f721f87cf00 R9: 0000000000000000 R10: 00007ffc0d54a32a R11: 0000000000000246 R12: 00007f721e09b3c0 R13: 000055606b81376e R14: 0000000000000013 R15: 00007f721e09b3c0 ORIG_RAX: 0000000000000005 CS: 0033 SS: 002b Ben