From patchwork Thu Nov 15 19:51:33 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jens Axboe X-Patchwork-Id: 10684979 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E1FAA17EE for ; Thu, 15 Nov 2018 19:51:59 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D174D2D0EC for ; Thu, 15 Nov 2018 19:51:59 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id CFC112D16A; Thu, 15 Nov 2018 19:51:59 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 71F812D14E for ; Thu, 15 Nov 2018 19:51:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729263AbeKPGBK (ORCPT ); Fri, 16 Nov 2018 01:01:10 -0500 Received: from mail-pl1-f193.google.com ([209.85.214.193]:42847 "EHLO mail-pl1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725781AbeKPGBK (ORCPT ); Fri, 16 Nov 2018 01:01:10 -0500 Received: by mail-pl1-f193.google.com with SMTP id x21-v6so7241864pln.9 for ; Thu, 15 Nov 2018 11:51:58 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=UjKFPPY66VB4W6EBmXfarxZuGQQ5lRuC6yiN12FUde8=; b=Z0vv1NFk8YfS0Xj6QE28UswnkjV973Br90CAQ8O6HCiICvXWAb2OMXpKOdgRDrBShq fgMc2QH/gu3UkcxH+WvZrgDYGOLdtNmC5l0EAQ5fXWhZuWomVrx7CsErgwbt9qAmV5C4 M/6nu6f3UUyH2l7xf7V379Fi7Xqdhb8AKlj9AvgG4+Znb3jgydg6C4aygysDhK2bfrPt u5PZSHe3R/v2lC7i4Qsv2SnHMnvG8JD+EM8DQ1epe6p3e0BZIRkPQ8OhNy/7XjPOPZZn wHT/zU7XLGd29fw0nT6BwF8k4DyOpw16oY0qXaIcY84JgOouOVXlHK+phoGypW3eOBKA Z5iQ== 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; bh=UjKFPPY66VB4W6EBmXfarxZuGQQ5lRuC6yiN12FUde8=; b=Irj5Rmnrp19Uh1XjlD5BexmZRWsIyuEymoCH3KeyeqdARjc+8vF+AzpzCZY1UU283E /U7KNgZzf6QTAZVMHGYe2xQlfDn3lQoOcdpBCk6805NPr1sBWdpaWuQkSgpeoE12RWKB 7PB9oMH0clt7Sr3YotfGKQOea7SwjgZKrOak+dpwIgWQB+N0qGVPWLyGtBWSEFpI6tCa Fab8n7N2E2u01ljI0SRdMs1pANerkXYgNpopQGRM+lnC8haAiyCSopjgJIhPkMxd+j4g j5D1lkI4/w3aertiV+4YMrCL6AqBGxLXU8FHvJAoiRtBWhzV9sXZTxATSezyjGk5lhF1 OqgQ== X-Gm-Message-State: AGRZ1gKdwbhYm61roqqMw3a0hboFjMMevWSGNEAIQqoAFWABH0OJebLv CPOF8ia1JfdZoYSs7/uq4JYprSvdUf4= X-Google-Smtp-Source: AJdET5dKp4SIOsgjibHOjeqebQ2SYxZIXGybbY6STVljeN5N95MW/QlKZJ4X5Fo3mV6Q2iCkh+gJwQ== X-Received: by 2002:a17:902:2bc5:: with SMTP id l63-v6mr7681411plb.241.1542311517808; Thu, 15 Nov 2018 11:51:57 -0800 (PST) Received: from x1.localdomain ([2620:10d:c090:180::1:7813]) by smtp.gmail.com with ESMTPSA id d68-v6sm30670766pfa.80.2018.11.15.11.51.56 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 15 Nov 2018 11:51:56 -0800 (PST) From: Jens Axboe To: linux-block@vger.kernel.org Cc: Jens Axboe Subject: [PATCH 09/11] blk-mq: ensure mq_ops ->poll() is entered at least once Date: Thu, 15 Nov 2018 12:51:33 -0700 Message-Id: <20181115195135.22812-10-axboe@kernel.dk> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181115195135.22812-1-axboe@kernel.dk> References: <20181115195135.22812-1-axboe@kernel.dk> Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Right now we immediately bail if need_resched() is true, but we need to do at least one loop in case we have entries waiting. So just invert the need_resched() check, putting it at the bottom of the loop. Signed-off-by: Jens Axboe --- block/blk-mq.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 695aa9363a6e..0ff70dfc8c0e 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -3336,7 +3336,7 @@ static int __blk_mq_poll(struct blk_mq_hw_ctx *hctx, bool spin) hctx->poll_considered++; state = current->state; - while (!need_resched()) { + do { int ret; hctx->poll_invoked++; @@ -3356,7 +3356,7 @@ static int __blk_mq_poll(struct blk_mq_hw_ctx *hctx, bool spin) if (ret < 0 || !spin) break; cpu_relax(); - } + } while (!need_resched()); __set_current_state(TASK_RUNNING); return 0;