From patchwork Mon Sep 17 21:35:42 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bart Van Assche X-Patchwork-Id: 10603493 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 1E9351508 for ; Mon, 17 Sep 2018 22:19:45 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 119832A76B for ; Mon, 17 Sep 2018 22:19:45 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 05E9C2A771; Mon, 17 Sep 2018 22:19:45 +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=-7.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI,T_DKIM_INVALID 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 794142A76B for ; Mon, 17 Sep 2018 22:19:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728475AbeIRDtA (ORCPT ); Mon, 17 Sep 2018 23:49:00 -0400 Received: from com-out001.mailprotect.be ([83.217.72.83]:36861 "EHLO com-out001.mailprotect.be" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728023AbeIRDtA (ORCPT ); Mon, 17 Sep 2018 23:49:00 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=mailprotect.be; s=mail; h=Content-Transfer-Encoding:MIME-Version:References :In-Reply-To:Message-Id:Date:Subject:Cc:To:From:reply-to:sender:bcc: content-type; bh=E8veB/kZVZudCFUug/8eTrq84I9Xx4qKGU1eEKsPGUc=; b=A4Y/xc24vUef VNCslpwMobaB/UD4cwYsr2XFE+sGSDmDzOvCJv04xI6db7KonWapLeJ9U8xw6dZCBIYRkKbmFddMP jBJvQ/l51yufGV2vwJ0pU7THsFkOnLLpnlkVd+ioUKgdmxGjUGdz5IVPqyYvRpVGdHuChCxZ91DRK WTA9cy8cSwrfa1Def9O/snx2B7UR6ePwGwLUu8DIRj+Vl6tOGE+hb/3S5P0fHSv5u9xz+QFIYzpIL qV2bO38PtvhOs8azAaP4M0EPlkcV07OPijS/zNAwPf82hmOywulea5UrcqRUVIcOqMQy0z6Q9XBxz erFH4WqN8OC4FR3xmsEDdw==; Received: from smtp-auth.mailprotect.be ([178.208.39.155]) by com-mpt-out001.mailprotect.be with esmtp (Exim 4.89) (envelope-from ) id 1g21Br-000ArF-Fw; Mon, 17 Sep 2018 23:36:20 +0200 Received: from asus.hsd1.ca.comcast.net (c-174-62-111-89.hsd1.ca.comcast.net [174.62.111.89]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp-auth.mailprotect.be (Postfix) with ESMTPSA id 6A670C0771; Mon, 17 Sep 2018 23:36:17 +0200 (CEST) From: Bart Van Assche To: "Martin K . Petersen" Cc: Christoph Hellwig , target-devel@vger.kernel.org, Bart Van Assche , Nicholas Bellinger , Mike Christie , Hannes Reinecke Subject: [PATCH 05/17] target/core: Make sure that target_wait_for_sess_cmds() waits long enough Date: Mon, 17 Sep 2018 14:35:42 -0700 Message-Id: <20180917213554.987-6-bvanassche@acm.org> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180917213554.987-1-bvanassche@acm.org> References: <20180917213554.987-1-bvanassche@acm.org> MIME-Version: 1.0 X-Originating-IP: 178.208.39.155 X-SpamExperts-Domain: mailprotect.be X-SpamExperts-Username: 178.208.39.128/27 Authentication-Results: mailprotect.be; auth=pass smtp.auth=178.208.39.128/27@mailprotect.be X-SpamExperts-Outgoing-Class: ham X-SpamExperts-Outgoing-Evidence: Combined (0.05) X-Recommended-Action: accept X-Filter-ID: EX5BVjFpneJeBchSMxfU5guRRbidmbWvwWnFk6LV9uF602E9L7XzfQH6nu9C/Fh9KJzpNe6xgvOx q3u0UDjvO1tLifGj39bI0bcPyaJsYTagCTS5H5Pie2sCQ3gGSzr06cM7U7xDGmYwNG93LVnxwxjk yGQYCd08t3lHobjxX/OigDGQOIiVUN5rGO3B5zfVpnsdsF0/474T9aStD4uEKVG9P9yTThxC66Ku Xb0HO3WlZa4xKvcBORT2AGmYYKfacHGRHPT1S45qX7/AQuG3+Xws3TRjaC42FtNJuTWwh7zLjlV5 cBkg2E15FOz6ftN7WN260MwZf1g7kEhu0P/R6s902MBxp+G42GIBqokZAnJ5xBHkCMCjMposz65/ e+f6NiSg6RpPztwkEB6XvRg4fu70pheH5TNN6RiG9N0Jt+0ML5i3g2GFaGQnZ3KowlU8anvoc7s0 eHtsyrH7f4vWsxE/6wnSTdYMIbg1/h42t37X7D3r+yzaf09FesHDYiVh+mW6KLAhhg63cf8hhJ+u kSXGkMRHqahP8I2z5Z6Oaau3r5afqv7IHvnvd2pvgvBc+yIcNf9mmCdHYvplLFSG4KBSfNBRSHvO tj6BxxAeW8VFuiO6yCEAclVLBw8e/TPckDkXGJvniGivX1Fq/UQDdfRWNiJbKFZUCBFMj3aVfRTy mM4V+dYvw3zgaX5MC+SYhClGQqBaLo/4e5RWTejdpMF40MajfsURz8L4dmQLKmXZ4ciB+h1c4Cwq mt5tbitpDjKIx3H3dmYdnoX9+S6u9FHoNcKBKpwOsM0bgp36P+fUL1JgezUdWQ05VsGirfnatW1x D7NPHFVkxC5YVnU16UjwG05S+hO4GQ05Y/WP30Hdn+cousT5+gFGAcOaNJ6l53AchVbc0JpeNrhF rx64zcw4Oh2LkwsmIC+tUiJAU2GWfmVpiJkOE4Udd79N8qTYcd4qMwgBY2sSVlk3aKxhghxwEiTV JqDh0qKoKsXx5lnwVAtFIjOqBVBmDBo6d1b4QpW0dpxIo9d2WgcHzHNTu4W3OyTlA5uhTP73RN8y cSzpfj5sSQhb3cc4IkKXIhy+I6DM7/owTL8J95f1/+MXnOL6CZv+n8/wRksD+x9JjG1O+eyolGM4 l8rlxuGfhU+34hrNm42X2UZAYRVVEuFqpn0Wcxxec4eIhtK5Pi2eqhlDMrilbtDDvtO4rayUOwaR X-Report-Abuse-To: spam@com-mpt-mgt001.mailprotect.be Sender: target-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: target-devel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP A session must only be released after all code that accesses the session structure has finished. Make sure that this is the case by introducing a new command counter per session that is only decremented after the .release_cmd() callback has finished. Signed-off-by: Bart Van Assche Cc: Nicholas Bellinger Cc: Mike Christie Cc: Christoph Hellwig Cc: Hannes Reinecke --- drivers/target/target_core_transport.c | 27 +++++++++++++++++--------- include/target/target_core_base.h | 1 + 2 files changed, 19 insertions(+), 9 deletions(-) diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 94e9d03af99d..54ccd8f56a57 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -224,6 +224,13 @@ void transport_subsystem_check_init(void) sub_api_initialized = 1; } +static void target_release_sess_cmd_refcnt(struct percpu_ref *ref) +{ + struct se_session *sess = container_of(ref, typeof(*sess), cmd_count); + + wake_up(&sess->cmd_list_wq); +} + /** * transport_init_session - initialize a session object * @se_sess: Session object pointer. @@ -237,7 +244,8 @@ int transport_init_session(struct se_session *se_sess) INIT_LIST_HEAD(&se_sess->sess_cmd_list); spin_lock_init(&se_sess->sess_cmd_lock); init_waitqueue_head(&se_sess->cmd_list_wq); - return 0; + return percpu_ref_init(&se_sess->cmd_count, + target_release_sess_cmd_refcnt, 0, GFP_KERNEL); } EXPORT_SYMBOL(transport_init_session); @@ -587,6 +595,7 @@ void transport_free_session(struct se_session *se_sess) sbitmap_queue_free(&se_sess->sess_tag_pool); kvfree(se_sess->sess_cmd_map); } + percpu_ref_exit(&se_sess->cmd_count); kmem_cache_free(se_sess_cache, se_sess); } EXPORT_SYMBOL(transport_free_session); @@ -2730,6 +2739,7 @@ int target_get_sess_cmd(struct se_cmd *se_cmd, bool ack_kref) } se_cmd->transport_state |= CMD_T_PRE_EXECUTE; list_add_tail(&se_cmd->se_cmd_list, &se_sess->sess_cmd_list); + percpu_ref_get(&se_sess->cmd_count); out: spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags); @@ -2760,8 +2770,6 @@ static void target_release_cmd_kref(struct kref *kref) if (se_sess) { spin_lock_irqsave(&se_sess->sess_cmd_lock, flags); list_del_init(&se_cmd->se_cmd_list); - if (list_empty(&se_sess->sess_cmd_list)) - wake_up(&se_sess->cmd_list_wq); spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags); } @@ -2769,6 +2777,8 @@ static void target_release_cmd_kref(struct kref *kref) se_cmd->se_tfo->release_cmd(se_cmd); if (compl) complete(compl); + + percpu_ref_put(&se_sess->cmd_count); } /** @@ -2897,6 +2907,8 @@ void target_sess_cmd_list_set_waiting(struct se_session *se_sess) spin_lock_irqsave(&se_sess->sess_cmd_lock, flags); se_sess->sess_tearing_down = 1; spin_unlock_irqrestore(&se_sess->sess_cmd_lock, flags); + + percpu_ref_kill_and_confirm(&se_sess->cmd_count, NULL); } EXPORT_SYMBOL(target_sess_cmd_list_set_waiting); @@ -2911,17 +2923,14 @@ void target_wait_for_sess_cmds(struct se_session *se_sess) WARN_ON_ONCE(!se_sess->sess_tearing_down); - spin_lock_irq(&se_sess->sess_cmd_lock); do { - ret = wait_event_interruptible_lock_irq_timeout( - se_sess->cmd_list_wq, - list_empty(&se_sess->sess_cmd_list), - se_sess->sess_cmd_lock, 180 * HZ); + ret = wait_event_timeout(se_sess->cmd_list_wq, + percpu_ref_is_zero(&se_sess->cmd_count), + 180 * HZ); list_for_each_entry(cmd, &se_sess->sess_cmd_list, se_cmd_list) target_show_cmd("session shutdown: still waiting for ", cmd); } while (ret <= 0); - spin_unlock_irq(&se_sess->sess_cmd_lock); } EXPORT_SYMBOL(target_wait_for_sess_cmds); diff --git a/include/target/target_core_base.h b/include/target/target_core_base.h index 7a4ee7852ca4..2cfd3b4573b0 100644 --- a/include/target/target_core_base.h +++ b/include/target/target_core_base.h @@ -602,6 +602,7 @@ struct se_session { struct se_node_acl *se_node_acl; struct se_portal_group *se_tpg; void *fabric_sess_ptr; + struct percpu_ref cmd_count; struct list_head sess_list; struct list_head sess_acl_list; struct list_head sess_cmd_list;