From owner-dev-commits-src-main@freebsd.org Sat Apr 3 12:27:34 2021 Return-Path: Delivered-To: dev-commits-src-main@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 7FC495B3CE4; Sat, 3 Apr 2021 12:27:34 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4FCGQZ36pDz3w8D; Sat, 3 Apr 2021 12:27:34 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 5912D130C1; Sat, 3 Apr 2021 12:27:34 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.16.1/8.16.1) with ESMTP id 133CRYtq052031; Sat, 3 Apr 2021 12:27:34 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 133CRYbN052030; Sat, 3 Apr 2021 12:27:34 GMT (envelope-from git) Date: Sat, 3 Apr 2021 12:27:34 GMT Message-Id: <202104031227.133CRYbN052030@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Edward Tomasz Napierala Subject: git: 7f6157f7fd12 - main - lock_delay(9): improve interaction with restrict_starvation MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: trasz X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: 7f6157f7fd12608ccb96c8a571b9352bf9968d8f Auto-Submitted: auto-generated X-BeenThere: dev-commits-src-main@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Commit messages for the main branch of the src repository List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 03 Apr 2021 12:27:34 -0000 The branch main has been updated by trasz: URL: https://cgit.FreeBSD.org/src/commit/?id=7f6157f7fd12608ccb96c8a571b9352bf9968d8f commit 7f6157f7fd12608ccb96c8a571b9352bf9968d8f Author: Edward Tomasz Napierala AuthorDate: 2021-04-03 12:08:45 +0000 Commit: Edward Tomasz Napierala CommitDate: 2021-04-03 12:08:53 +0000 lock_delay(9): improve interaction with restrict_starvation After e7a5b3bd058, the la->delay value was adjusted after being set by the starvation_limit code block, which is wrong. Reported By: avg Reviewed By: avg Fixes: e7a5b3bd058 Sponsored By: NetApp, Inc. Sponsored By: Klara, Inc. Differential Revision: https://reviews.freebsd.org/D29513 --- sys/kern/subr_lock.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/sys/kern/subr_lock.c b/sys/kern/subr_lock.c index 8b08c61715b3..1afaa19302ed 100644 --- a/sys/kern/subr_lock.c +++ b/sys/kern/subr_lock.c @@ -130,17 +130,17 @@ lock_delay(struct lock_delay_arg *la) for (i = la->delay; i > 0; i--) cpu_spinwait(); - la->spin_cnt += la->delay; + + la->delay <<= 1; + if (__predict_false(la->delay > lc->max)) + la->delay = lc->max; + if (__predict_false(la->spin_cnt > starvation_limit)) { SDT_PROBE1(lock, , , starvation, la->delay); if (restrict_starvation) la->delay = lc->base; } - - la->delay <<= 1; - if (__predict_false(la->delay > lc->max)) - la->delay = lc->max; } static u_int