From owner-freebsd-bugs@FreeBSD.ORG Sun Feb 22 15:16:32 2015 Return-Path: Delivered-To: freebsd-bugs@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 3AC509E8 for ; Sun, 22 Feb 2015 15:16:32 +0000 (UTC) Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2001:1900:2254:206a::16:76]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 20B69D9A for ; Sun, 22 Feb 2015 15:16:32 +0000 (UTC) Received: from bugs.freebsd.org ([127.0.1.118]) by kenobi.freebsd.org (8.14.9/8.14.9) with ESMTP id t1MFGV7B099733 for ; Sun, 22 Feb 2015 15:16:31 GMT (envelope-from bugzilla-noreply@freebsd.org) From: bugzilla-noreply@freebsd.org To: freebsd-bugs@FreeBSD.org Subject: [Bug 197922] [patch] [sched] Remove random() from sched_ule, add short circuit for non-SMP, non-balancing Date: Sun, 22 Feb 2015 15:16:32 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: kern X-Bugzilla-Version: 11.0-CURRENT X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Only Me X-Bugzilla-Who: harrison.grundy@astrodoggroup.com X-Bugzilla-Status: New X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: freebsd-bugs@FreeBSD.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version rep_platform op_sys bug_status bug_severity priority component assigned_to reporter attachments.created Message-ID: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: freebsd-bugs@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 22 Feb 2015 15:16:32 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=197922 Bug ID: 197922 Summary: [patch] [sched] Remove random() from sched_ule, add short circuit for non-SMP, non-balancing Product: Base System Version: 11.0-CURRENT Hardware: Any OS: Any Status: New Severity: Affects Only Me Priority: --- Component: kern Assignee: freebsd-bugs@FreeBSD.org Reporter: harrison.grundy@astrodoggroup.com Created attachment 153317 --> https://bugs.freebsd.org/bugzilla/attachment.cgi?id=153317&action=edit Replace random with get_cyclecount as a suitable source of entropy for the balancer. Short circuit for non-SMP/Balance As discovered by John-Mark Gurney, ULE uses random() which is not SMP/preemption safe. Move the check for SMP and Balancer being enabled above the generation of the balancing interval. -- You are receiving this mail because: You are the assignee for the bug.