From owner-svn-src-head@freebsd.org Tue Aug 4 23:00:01 2020 Return-Path: Delivered-To: svn-src-head@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 1A0093A29DD; Tue, 4 Aug 2020 23:00:01 +0000 (UTC) (envelope-from mjg@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 "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4BLqw06q9zz411c; Tue, 4 Aug 2020 23:00:00 +0000 (UTC) (envelope-from mjg@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id CE82BCAFC; Tue, 4 Aug 2020 23:00:00 +0000 (UTC) (envelope-from mjg@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id 074N00nd021198; Tue, 4 Aug 2020 23:00:00 GMT (envelope-from mjg@FreeBSD.org) Received: (from mjg@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id 074N00Do021197; Tue, 4 Aug 2020 23:00:00 GMT (envelope-from mjg@FreeBSD.org) Message-Id: <202008042300.074N00Do021197@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: mjg set sender to mjg@FreeBSD.org using -f From: Mateusz Guzik Date: Tue, 4 Aug 2020 23:00:00 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r363871 - in head/sys: kern sys X-SVN-Group: head X-SVN-Commit-Author: mjg X-SVN-Commit-Paths: in head/sys: kern sys X-SVN-Commit-Revision: 363871 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.33 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 04 Aug 2020 23:00:01 -0000 Author: mjg Date: Tue Aug 4 23:00:00 2020 New Revision: 363871 URL: https://svnweb.freebsd.org/changeset/base/363871 Log: mtx: add mtx_wait_unlocked Modified: head/sys/kern/kern_mutex.c head/sys/sys/mutex.h Modified: head/sys/kern/kern_mutex.c ============================================================================== --- head/sys/kern/kern_mutex.c Tue Aug 4 21:58:43 2020 (r363870) +++ head/sys/kern/kern_mutex.c Tue Aug 4 23:00:00 2020 (r363871) @@ -1275,6 +1275,35 @@ mtx_spin_wait_unlocked(struct mtx *m) } } +void +mtx_wait_unlocked(struct mtx *m) +{ + struct thread *owner; + uintptr_t v; + + KASSERT(m->mtx_lock != MTX_DESTROYED, + ("%s() of destroyed mutex %p", __func__, m)); + KASSERT(LOCK_CLASS(&m->lock_object) == &lock_class_mtx_sleep, + ("%s() not a sleep mutex %p (%s)", __func__, m, + m->lock_object.lo_name)); + KASSERT(!mtx_owned(m), ("%s() waiting on myself on lock %p (%s)", __func__, m, + m->lock_object.lo_name)); + + for (;;) { + v = atomic_load_acq_ptr(&m->mtx_lock); + if (v == MTX_UNOWNED) { + break; + } + owner = lv_mtx_owner(v); + if (!TD_IS_RUNNING(owner)) { + mtx_lock(m); + mtx_unlock(m); + break; + } + cpu_spinwait(); + } +} + #ifdef DDB void db_show_mtx(const struct lock_object *lock) Modified: head/sys/sys/mutex.h ============================================================================== --- head/sys/sys/mutex.h Tue Aug 4 21:58:43 2020 (r363870) +++ head/sys/sys/mutex.h Tue Aug 4 23:00:00 2020 (r363871) @@ -106,6 +106,7 @@ void __mtx_unlock_sleep(volatile uintptr_t *c, uintptr void __mtx_lock_sleep(volatile uintptr_t *c, uintptr_t v); void __mtx_unlock_sleep(volatile uintptr_t *c, uintptr_t v); #endif +void mtx_wait_unlocked(struct mtx *m); #ifdef SMP #if LOCK_DEBUG > 0