From patchwork Tue Sep 29 14:04:19 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chuck Lever X-Patchwork-Id: 11806029 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B2525112C for ; Tue, 29 Sep 2020 14:04:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8EF7C2145D for ; Tue, 29 Sep 2020 14:04:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="VUl+ndd0" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730962AbgI2OEW (ORCPT ); Tue, 29 Sep 2020 10:04:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33136 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730082AbgI2OEW (ORCPT ); Tue, 29 Sep 2020 10:04:22 -0400 Received: from mail-il1-x143.google.com (mail-il1-x143.google.com [IPv6:2607:f8b0:4864:20::143]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D1201C061755 for ; Tue, 29 Sep 2020 07:04:21 -0700 (PDT) Received: by mail-il1-x143.google.com with SMTP id e5so2051808ils.10 for ; Tue, 29 Sep 2020 07:04:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:subject:from:to:cc:date:message-id:in-reply-to:references :user-agent:mime-version:content-transfer-encoding; bh=uOznGB4P4Ui9gKYW2dTlrXuCNu7sERkmQkAAQJFtOyM=; b=VUl+ndd0a/zEYO6z0ZwvJENg5AjO6t80pALjXtSslTRYRds9YISVaDBWlhTOqoS1zt gKEq18teAzZHPA9Zb3wXQdpVBzISyrylPoocWIWc6EnEDHQoY6EpwSX/BEaYgpCb9awJ WlAEoimgRIjdwHq2hizc2/lavSdjUWt9Fsgzm7IXoR/wUo/hf8BYcMXOxpfM384D7rC0 d0k/25BYpHWEXQ+8XaiNwac76XEDtrjNohATay5XYWpxo7ZZPcNtWE8ZafRvrpVzzNc2 Rph1+eVOHl5RgwaUpXDr/pKpfQjlb6hqvqNcn+M7ESvbYvLiC48ZFOLQxU1Gw+XBqZ5V ZMrQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:subject:from:to:cc:date:message-id :in-reply-to:references:user-agent:mime-version :content-transfer-encoding; bh=uOznGB4P4Ui9gKYW2dTlrXuCNu7sERkmQkAAQJFtOyM=; b=mF7uA0uS+NNdXYcvZpVM+az3V0fvWgVxTEQhHdL0NKfqzXvjjGSbYiBwJqn6nAI7M+ JYpRibrl/zbr45fen7gjVW8QnGdLFp98sDAFrEr+VOdSAl7HDAh67THWixRcC6Wq8PRv nwLsxSyL51ttrAGp5CUOgaA1DRh6sDN8lfuJGhU7NlVvKaNX0PqFkhY+1PW2uySMixfz LJZB15mm5/yMKoRclW2YHet+1h8dATQZ4MiCSL03L9J2AjJtCvorh+9f+dtkrVANiYmt 9Ja+6hSGp5QVlwkoFbulbfJ9VNfsnx58fxmmW7o7JBZhowZ9st4GiMSe9hfgeNm2u/+8 YjCA== X-Gm-Message-State: AOAM531a7H+UPxk92px1CJS0JTnFIdVpIl3Ju06KtdZbs/UfkuFPWKhd dvoPKpr5UqjcRb/59cwbxPm/y7HvmJvZ9A== X-Google-Smtp-Source: ABdhPJzxSqSBBI9hKknVyUgWFohCwblY8vztQr8u4tqipMukJBImR0pBoPyxcckPTqZcqhD3++sCgw== X-Received: by 2002:a92:d8d0:: with SMTP id l16mr3269908ilo.47.1601388261179; Tue, 29 Sep 2020 07:04:21 -0700 (PDT) Received: from gateway.1015granger.net (c-68-61-232-219.hsd1.mi.comcast.net. [68.61.232.219]) by smtp.gmail.com with ESMTPSA id l6sm2393959ilo.21.2020.09.29.07.04.20 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Tue, 29 Sep 2020 07:04:20 -0700 (PDT) Sender: Chuck Lever Received: from klimt.1015granger.net (klimt.1015granger.net [192.168.1.55]) by gateway.1015granger.net (8.14.7/8.14.7) with ESMTP id 08TE4JEE026436; Tue, 29 Sep 2020 14:04:19 GMT Subject: [PATCH v2 08/11] NFSD: Refactor nfsd_dispatch() error paths From: Chuck Lever To: bfields@fieldses.org Cc: linux-nfs@vger.kernel.org Date: Tue, 29 Sep 2020 10:04:19 -0400 Message-ID: <160138825933.2558.7100398429811622816.stgit@klimt.1015granger.net> In-Reply-To: <160138785101.2558.11821923574884893011.stgit@klimt.1015granger.net> References: <160138785101.2558.11821923574884893011.stgit@klimt.1015granger.net> User-Agent: StGit/0.23-29-ga622f1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org nfsd_dispatch() is a hot path. Ensure the compiler takes the processing of infrequent errors out of line. Signed-off-by: Chuck Lever --- fs/nfsd/nfssvc.c | 60 ++++++++++++++++++++++++++++++++---------------------- 1 file changed, 35 insertions(+), 25 deletions(-) diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c index 18ec22a8580a..283d29ecae43 100644 --- a/fs/nfsd/nfssvc.c +++ b/fs/nfsd/nfssvc.c @@ -1021,29 +1021,24 @@ int nfsd_dispatch(struct svc_rqst *rqstp, __be32 *statp) dprintk("nfsd_dispatch: vers %d proc %d\n", rqstp->rq_vers, rqstp->rq_proc); - if (nfs_request_too_big(rqstp, proc)) { - dprintk("nfsd: NFSv%d argument too large\n", rqstp->rq_vers); - *statp = rpc_garbage_args; - return 1; - } + if (nfs_request_too_big(rqstp, proc)) + goto out_too_large; + /* * Give the xdr decoder a chance to change this if it wants * (necessary in the NFSv4.0 compound case) */ rqstp->rq_cachetype = proc->pc_cachetype; - if (!proc->pc_decode(rqstp, argv->iov_base)) { - dprintk("nfsd: failed to decode arguments!\n"); - *statp = rpc_garbage_args; - return 1; - } + if (!proc->pc_decode(rqstp, argv->iov_base)) + goto out_decode_err; switch (nfsd_cache_lookup(rqstp)) { case RC_DOIT: break; case RC_REPLY: - return 1; + goto out_cached_reply; case RC_DROPIT: - return 0; + goto out_dropit; } /* @@ -1055,11 +1050,8 @@ int nfsd_dispatch(struct svc_rqst *rqstp, __be32 *statp) nfserr = proc->pc_func(rqstp); nfserr = map_new_errors(rqstp->rq_vers, nfserr); - if (nfserr == nfserr_dropit || test_bit(RQ_DROPME, &rqstp->rq_flags)) { - dprintk("nfsd: Dropping request; may be revisited later\n"); - nfsd_cache_update(rqstp, RC_NOCACHE, NULL); - return 0; - } + if (nfserr == nfserr_dropit || test_bit(RQ_DROPME, &rqstp->rq_flags)) + goto out_update_drop; if (rqstp->rq_proc != 0) *p++ = nfserr; @@ -1067,16 +1059,34 @@ int nfsd_dispatch(struct svc_rqst *rqstp, __be32 *statp) /* * For NFSv2, additional info is never returned in case of an error. */ - if (!(nfserr && rqstp->rq_vers == 2)) { - if (!proc->pc_encode(rqstp, p)) { - dprintk("nfsd: failed to encode result!\n"); - nfsd_cache_update(rqstp, RC_NOCACHE, NULL); - *statp = rpc_system_err; - return 1; - } - } + if (!(nfserr && rqstp->rq_vers == 2)) + if (!proc->pc_encode(rqstp, p)) + goto out_encode_err; nfsd_cache_update(rqstp, rqstp->rq_cachetype, statp + 1); +out_cached_reply: + return 1; + +out_too_large: + dprintk("nfsd: NFSv%d argument too large\n", rqstp->rq_vers); + *statp = rpc_garbage_args; + return 1; + +out_decode_err: + dprintk("nfsd: failed to decode arguments!\n"); + *statp = rpc_garbage_args; + return 1; + +out_update_drop: + dprintk("nfsd: Dropping request; may be revisited later\n"); + nfsd_cache_update(rqstp, RC_NOCACHE, NULL); +out_dropit: + return 0; + +out_encode_err: + dprintk("nfsd: failed to encode result!\n"); + nfsd_cache_update(rqstp, RC_NOCACHE, NULL); + *statp = rpc_system_err; return 1; }