From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx.sdf.org ([205.166.94.20]:50199 "EHLO mx.sdf.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727461AbgC1QnV (ORCPT ); Sat, 28 Mar 2020 12:43:21 -0400 Message-Id: <202003281643.02SGhHN7015213@sdf.org> From: George Spelvin Date: Fri, 29 Nov 2019 15:39:41 -0500 Subject: [RFC PATCH v1 27/50] drivers/s390/scsi/zcsp_fc.c: Use prandom_u32_max() for backoff Sender: linux-s390-owner@vger.kernel.org List-ID: To: linux-kernel@vger.kernel.org, lkml@sdf.org Cc: Heiko Carstens , Vasily Gorbik , Christian Borntraeger , linux-s390@vger.kernel.org We don't need crypto-grade random numbers for randomized backoffs. (We could skip the if() if we wanted to rely on the undocumented fact that prandom_u32_max(0) always returns 0. That would be a net time saving it port_scan_backoff == 0 is rare; if it's common, the if() is false often enough to pay for itself. Not sure which applies here.) Signed-off-by: George Spelvin Cc: Heiko Carstens Cc: Vasily Gorbik Cc: Christian Borntraeger Cc: linux-s390@vger.kernel.org --- drivers/s390/scsi/zfcp_fc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/s390/scsi/zfcp_fc.c b/drivers/s390/scsi/zfcp_fc.c index b018b61bd168e..d24cafe02708f 100644 --- a/drivers/s390/scsi/zfcp_fc.c +++ b/drivers/s390/scsi/zfcp_fc.c @@ -48,7 +48,7 @@ unsigned int zfcp_fc_port_scan_backoff(void) { if (!port_scan_backoff) return 0; - return get_random_int() % port_scan_backoff; + return prandom_u32_max(port_scan_backoff); } static void zfcp_fc_port_scan_time(struct zfcp_adapter *adapter) -- 2.26.0