From patchwork Fri Mar 27 05:33:01 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Long Li X-Patchwork-Id: 11461661 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 9E9CF14B4 for ; Fri, 27 Mar 2020 05:33:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 781B6206DB for ; Fri, 27 Mar 2020 05:33:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=linuxonhyperv.com header.i=@linuxonhyperv.com header.b="Pw7xdQOg" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726096AbgC0FdR (ORCPT ); Fri, 27 Mar 2020 01:33:17 -0400 Received: from linux.microsoft.com ([13.77.154.182]:38140 "EHLO linux.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725956AbgC0FdQ (ORCPT ); Fri, 27 Mar 2020 01:33:16 -0400 Received: by linux.microsoft.com (Postfix, from userid 1004) id 4D4D220B4737; Thu, 26 Mar 2020 22:33:15 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 4D4D220B4737 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxonhyperv.com; s=default; t=1585287195; bh=p8YGRod+AoZSOG+yxhDi9CuAIYPiAdJpgka/fXNPphE=; h=From:To:Cc:Subject:Date:Reply-To:From; b=Pw7xdQOgpEi/d7fkjjLUDr9c3giKGLWFJXVjlaWVukxdgRRM5roPWEdwwKWq22+FU QwkOue/d53Gs8nZtihhHrTZmzEB0UDl7P1b0EsLiEC1vn+76G0rAKlHgrgR3/jRE27 dqDVJgkbwrpu/fGAG6nZT93ZUIpmrhxwdtEPzQlc= From: longli@linuxonhyperv.com To: Steve French , linux-cifs@vger.kernel.org, samba-technical@lists.samba.org, linux-kernel@vger.kernel.org Cc: Long Li Subject: [PATCH] cifs: smbd: Check and extend sender credits in interrupt context Date: Thu, 26 Mar 2020 22:33:01 -0700 Message-Id: <1585287181-35333-1-git-send-email-longli@linuxonhyperv.com> X-Mailer: git-send-email 1.8.3.1 Reply-To: longli@microsoft.com Sender: linux-cifs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-cifs@vger.kernel.org From: Long Li When a RDMA packet is received and server is extending send credits, we should check and unblock senders immediately in IRQ context. Doing it in a worker queue causes unnecessary delay and doesn't save much CPU on the receive path. Signed-off-by: Long Li --- fs/cifs/smbdirect.c | 38 +++++++++++++++----------------------- fs/cifs/smbdirect.h | 1 - 2 files changed, 15 insertions(+), 24 deletions(-) diff --git a/fs/cifs/smbdirect.c b/fs/cifs/smbdirect.c index a6ae29b3c4e7..8da43a500686 100644 --- a/fs/cifs/smbdirect.c +++ b/fs/cifs/smbdirect.c @@ -459,25 +459,6 @@ static void smbd_post_send_credits(struct work_struct *work) check_and_send_immediate(info); } -static void smbd_recv_done_work(struct work_struct *work) -{ - struct smbd_connection *info = - container_of(work, struct smbd_connection, recv_done_work); - - /* - * We may have new send credits granted from remote peer - * If any sender is blcoked on lack of credets, unblock it - */ - if (atomic_read(&info->send_credits)) - wake_up_interruptible(&info->wait_send_queue); - - /* - * Check if we need to send something to remote peer to - * grant more credits or respond to KEEP_ALIVE packet - */ - check_and_send_immediate(info); -} - /* Called from softirq, when recv is done */ static void recv_done(struct ib_cq *cq, struct ib_wc *wc) { @@ -546,8 +527,15 @@ static void recv_done(struct ib_cq *cq, struct ib_wc *wc) atomic_dec(&info->receive_credits); info->receive_credit_target = le16_to_cpu(data_transfer->credits_requested); - atomic_add(le16_to_cpu(data_transfer->credits_granted), - &info->send_credits); + if (le16_to_cpu(data_transfer->credits_granted)) { + atomic_add(le16_to_cpu(data_transfer->credits_granted), + &info->send_credits); + /* + * We have new send credits granted from remote peer + * If any sender is waiting for credits, unblock it + */ + wake_up_interruptible(&info->wait_send_queue); + } log_incoming(INFO, "data flags %d data_offset %d " "data_length %d remaining_data_length %d\n", @@ -563,7 +551,12 @@ static void recv_done(struct ib_cq *cq, struct ib_wc *wc) info->keep_alive_requested = KEEP_ALIVE_PENDING; } - queue_work(info->workqueue, &info->recv_done_work); + /* + * Check if we need to send something to remote peer to + * grant more credits or respond to KEEP_ALIVE packet + */ + check_and_send_immediate(info); + return; default: @@ -1762,7 +1755,6 @@ static struct smbd_connection *_smbd_get_connection( atomic_set(&info->send_payload_pending, 0); INIT_WORK(&info->disconnect_work, smbd_disconnect_rdma_work); - INIT_WORK(&info->recv_done_work, smbd_recv_done_work); INIT_WORK(&info->post_send_credits_work, smbd_post_send_credits); info->new_credits_offered = 0; spin_lock_init(&info->lock_new_credits_offered); diff --git a/fs/cifs/smbdirect.h b/fs/cifs/smbdirect.h index 6ff880a1e186..8ede915f2b24 100644 --- a/fs/cifs/smbdirect.h +++ b/fs/cifs/smbdirect.h @@ -67,7 +67,6 @@ struct smbd_connection { bool negotiate_done; struct work_struct disconnect_work; - struct work_struct recv_done_work; struct work_struct post_send_credits_work; spinlock_t lock_new_credits_offered;