From patchwork Thu Jul 3 09:17:52 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luis Henriques X-Patchwork-Id: 366662 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id D81EF1400E8; Thu, 3 Jul 2014 19:23:43 +1000 (EST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1X2dEz-0003fg-9C; Thu, 03 Jul 2014 09:23:41 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1X2dCp-0002Nb-8z for kernel-team@lists.ubuntu.com; Thu, 03 Jul 2014 09:21:27 +0000 Received: from bl20-140-206.dsl.telepac.pt ([2.81.140.206] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1X2dCo-0005Ki-V4; Thu, 03 Jul 2014 09:21:27 +0000 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Subject: [PATCH 3.11 029/198] Target/iser: Fix hangs in connection teardown Date: Thu, 3 Jul 2014 10:17:52 +0100 Message-Id: <1404379241-8590-30-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1404379241-8590-1-git-send-email-luis.henriques@canonical.com> References: <1404379241-8590-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.11 Cc: Sagi Grimberg , Nicholas Bellinger X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.14 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: kernel-team-bounces@lists.ubuntu.com 3.11.10.13 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Sagi Grimberg commit 9d49f5e284e700576f3b65f1e28dea8539da6661 upstream. In ungraceful teardowns isert close flows seem racy such that isert_wait_conn hangs as RDMA_CM_EVENT_DISCONNECTED never gets invoked (no one called rdma_disconnect). Both graceful and ungraceful teardowns will have rx flush errors (isert posts a batch once connection is established). Once all flush errors are consumed we invoke isert_wait_conn and it will be responsible for calling rdma_disconnect. This way it can be sure that rdma_disconnect was called and it won't wait forever. This patch also removes the logout_posted indicator. either the logout completion was consumed and no problem decrementing the post_send_buf_count, or it was consumed as a flush error. no point of keeping it for isert_wait_conn as there is no danger that isert_conn will be accidentally removed while it is running. (Drop unnecessary sleep_on_conn_wait_comp check in isert_cq_rx_comp_err - nab) Signed-off-by: Sagi Grimberg Signed-off-by: Nicholas Bellinger Signed-off-by: Luis Henriques --- drivers/infiniband/ulp/isert/ib_isert.c | 31 ++++++++++--------------------- drivers/infiniband/ulp/isert/ib_isert.h | 1 - 2 files changed, 10 insertions(+), 22 deletions(-) diff --git a/drivers/infiniband/ulp/isert/ib_isert.c b/drivers/infiniband/ulp/isert/ib_isert.c index b65e0c1c931c..434113247c62 100644 --- a/drivers/infiniband/ulp/isert/ib_isert.c +++ b/drivers/infiniband/ulp/isert/ib_isert.c @@ -572,14 +572,10 @@ isert_disconnect_work(struct work_struct *work) isert_put_conn(isert_conn); return; } - if (!isert_conn->logout_posted) { - pr_debug("Calling rdma_disconnect for !logout_posted from" - " isert_disconnect_work\n"); - rdma_disconnect(isert_conn->conn_cm_id); - mutex_unlock(&isert_conn->conn_mutex); - iscsit_cause_connection_reinstatement(isert_conn->conn, 0); - goto wake_up; - } + + /* Send DREQ/DREP towards our initiator */ + rdma_disconnect(isert_conn->conn_cm_id); + mutex_unlock(&isert_conn->conn_mutex); wake_up: @@ -1437,11 +1433,8 @@ isert_do_control_comp(struct work_struct *work) break; case ISTATE_SEND_LOGOUTRSP: pr_debug("Calling iscsit_logout_post_handler >>>>>>>>>>>>>>\n"); - /* - * Call atomic_dec(&isert_conn->post_send_buf_count) - * from isert_wait_conn() - */ - isert_conn->logout_posted = true; + + atomic_dec(&isert_conn->post_send_buf_count); iscsit_logout_post_handler(cmd, cmd->conn); break; case ISTATE_SEND_TEXTRSP: @@ -1555,6 +1548,8 @@ isert_cq_rx_comp_err(struct isert_conn *isert_conn) isert_conn->state = ISER_CONN_DOWN; mutex_unlock(&isert_conn->conn_mutex); + iscsit_cause_connection_reinstatement(isert_conn->conn, 0); + complete(&isert_conn->conn_wait_comp_err); } @@ -2367,15 +2362,9 @@ static void isert_wait_conn(struct iscsi_conn *conn) struct isert_conn *isert_conn = conn->context; pr_debug("isert_wait_conn: Starting \n"); - /* - * Decrement post_send_buf_count for special case when called - * from isert_do_control_comp() -> iscsit_logout_post_handler() - */ - mutex_lock(&isert_conn->conn_mutex); - if (isert_conn->logout_posted) - atomic_dec(&isert_conn->post_send_buf_count); - if (isert_conn->conn_cm_id && isert_conn->state != ISER_CONN_DOWN) { + mutex_lock(&isert_conn->conn_mutex); + if (isert_conn->conn_cm_id) { pr_debug("Calling rdma_disconnect from isert_wait_conn\n"); rdma_disconnect(isert_conn->conn_cm_id); } diff --git a/drivers/infiniband/ulp/isert/ib_isert.h b/drivers/infiniband/ulp/isert/ib_isert.h index 3fe0299efc11..62a7a1de4365 100644 --- a/drivers/infiniband/ulp/isert/ib_isert.h +++ b/drivers/infiniband/ulp/isert/ib_isert.h @@ -78,7 +78,6 @@ struct isert_device; struct isert_conn { enum iser_conn_state state; - bool logout_posted; int post_recv_buf_count; atomic_t post_send_buf_count; u32 responder_resources;