Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755013AbdGJWr7 (ORCPT ); Mon, 10 Jul 2017 18:47:59 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:46441 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754996AbdGJWr5 (ORCPT ); Mon, 10 Jul 2017 18:47:57 -0400 From: Mauricio Faria de Oliveira To: jejb@linux.vnet.ibm.com, martin.petersen@oracle.com Cc: hare@suse.de, bart.vanassche@sandisk.com, linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 3/4] scsi: scsi_dh_alua: do not print RTPG state if it remains unavailable/standby Date: Mon, 10 Jul 2017 19:47:36 -0300 X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1499726857-7875-1-git-send-email-mauricfo@linux.vnet.ibm.com> References: <1499726857-7875-1-git-send-email-mauricfo@linux.vnet.ibm.com> X-TM-AS-MML: disable x-cbid: 17071022-0024-0000-0000-00000189DEE6 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17071022-0025-0000-0000-0000165208D7 Message-Id: <1499726857-7875-4-git-send-email-mauricfo@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-07-10_08:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1703280000 definitions=main-1707100389 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3032 Lines: 89 Path checkers will check paths of a port group in unavailable/standby state more frequently (as they are 'failed') - possibly for a long or indefinite period of time, and/or for a large number of paths. That might flood the kernel log with scsi_dh_alua RTPG state messages, due to the recheck scheduled in alua_check_sense() to update PG state. So, do not to print such message if unavailable/standby state remains (i.e., the PG did not transition to/from such states). All other cases continue to be printed. Signed-off-by: Mauricio Faria de Oliveira --- v2: - changed v1's alua_state_remains() into alua_rtpg_print_check(), which includes in the states (not) to print for (deduplicates code). - added support for Standby state too (requested in patch 1 of this set) (Bart Van Assche ) - remove superfluous parentheses in return statement. (Bart Van Assche ) - remove likely() hint (Bart Van Assche ) drivers/scsi/device_handler/scsi_dh_alua.c | 35 ++++++++++++++++++++++++++---- 1 file changed, 31 insertions(+), 4 deletions(-) diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c index 937341ddb767..e0bf0827a980 100644 --- a/drivers/scsi/device_handler/scsi_dh_alua.c +++ b/drivers/scsi/device_handler/scsi_dh_alua.c @@ -572,6 +572,30 @@ static void alua_rtpg_print_supported(struct scsi_device *sdev, } /* + * alua_rtpg_print_check - Whether to print RTPG state information + * on particular state transitions. + * @old_state: the old state value. + * @new_state: the new state value. + */ +static bool alua_rtpg_print_check(int old_state, int new_state) +{ + /* + * Do not print RTPG state information in case + * state remains either unavailable or standby. + * + * Print it for everything else. + */ + + switch (old_state) { + case SCSI_ACCESS_STATE_UNAVAILABLE: + case SCSI_ACCESS_STATE_STANDBY: + return old_state != new_state; + default: + return 1; + } +} + +/* * alua_rtpg - Evaluate REPORT TARGET GROUP STATES * @sdev: the device to be evaluated. * @@ -706,6 +730,7 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg) if ((tmp_pg == pg) || !(tmp_pg->flags & ALUA_PG_RUNNING)) { struct alua_dh_data *h; + int tmp_pg_state_orig = tmp_pg->state; tmp_pg->state = desc[0] & 0x0f; tmp_pg->pref = desc[0] >> 7; @@ -718,10 +743,12 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg) } rcu_read_unlock(); - if (tmp_pg == pg) - alua_rtpg_print_supported(sdev, tmp_pg, desc[1]); - else - alua_rtpg_print(sdev, tmp_pg); + if (alua_rtpg_print_check(tmp_pg_state_orig, tmp_pg->state)) { + if (tmp_pg == pg) + alua_rtpg_print_supported(sdev, tmp_pg, desc[1]); + else + alua_rtpg_print(sdev, tmp_pg); + } } spin_unlock_irqrestore(&tmp_pg->lock, flags); } -- 1.8.3.1