Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753523AbcKHIpM (ORCPT ); Tue, 8 Nov 2016 03:45:12 -0500 Received: from mx2.suse.de ([195.135.220.15]:47809 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752250AbcKHIpK (ORCPT ); Tue, 8 Nov 2016 03:45:10 -0500 From: Johannes Thumshirn To: "Martin K . Petersen" , James Bottomley Cc: Hannes Reinecke , Christoph Hellwig , Linux SCSI Mailinglist , Linux Kernel Mailinglist , Arnd Bergmann , Bart Van Assche , Johannes Thumshirn Subject: [PATCH] libfc: fix seconds_since_last_reset miscalculation Date: Tue, 8 Nov 2016 09:44:54 +0100 Message-Id: <1478594694-98847-1-git-send-email-jthumshirn@suse.de> X-Mailer: git-send-email 1.8.5.6 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1528 Lines: 41 Commit 540eb1eef 'scsi: libfc: fix seconds_since_last_reset calculation' removed the use of 'struct timespec' from fc_get_host_stats(). This broke the output of 'fcoeadm -s' after kernel 4.8-rc1 as lport->boot_time - jiffies could become negative as in this example: $ cat /sys/class/fc_host/host8/statistics/seconds_since_last_reset 0x10624dd2f1977b4 Take this into account so /sys/class/fc_host/hostX/statistics/seconds_since_last_reset is sane again. Fixes: 540eb1eef ('scsi: libfc: fix seconds_since_last_reset calculation') Signed-off-by: Johannes Thumshirn Tested-by: Holger Schranz --- drivers/scsi/libfc/fc_lport.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/scsi/libfc/fc_lport.c b/drivers/scsi/libfc/fc_lport.c index 04ce7cf..475c0a9 100644 --- a/drivers/scsi/libfc/fc_lport.c +++ b/drivers/scsi/libfc/fc_lport.c @@ -304,11 +304,15 @@ struct fc_host_statistics *fc_get_host_stats(struct Scsi_Host *shost) unsigned int cpu; u64 fcp_in_bytes = 0; u64 fcp_out_bytes = 0; + unsigned long boot_time = lport->boot_time; fc_stats = &lport->host_stats; memset(fc_stats, 0, sizeof(struct fc_host_statistics)); - fc_stats->seconds_since_last_reset = (lport->boot_time - jiffies) / HZ; + if (boot_time > jiffies) + fc_stats->seconds_since_last_reset = (boot_time - jiffies) / HZ; + else + fc_stats->seconds_since_last_reset = (jiffies - boot_time) / HZ; for_each_possible_cpu(cpu) { struct fc_stats *stats; -- 1.8.5.6