From owner-svn-src-head@FreeBSD.ORG Fri May 29 14:03:34 2009 Return-Path: Delivered-To: svn-src-head@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id D933F1065725; Fri, 29 May 2009 14:03:34 +0000 (UTC) (envelope-from jhb@FreeBSD.org) Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:4f8:fff6::2c]) by mx1.freebsd.org (Postfix) with ESMTP id BD7AD8FC24; Fri, 29 May 2009 14:03:34 +0000 (UTC) (envelope-from jhb@FreeBSD.org) Received: from svn.freebsd.org (localhost [127.0.0.1]) by svn.freebsd.org (8.14.3/8.14.3) with ESMTP id n4TE3Yf7076842; Fri, 29 May 2009 14:03:34 GMT (envelope-from jhb@svn.freebsd.org) Received: (from jhb@localhost) by svn.freebsd.org (8.14.3/8.14.3/Submit) id n4TE3YiR076840; Fri, 29 May 2009 14:03:34 GMT (envelope-from jhb@svn.freebsd.org) Message-Id: <200905291403.n4TE3YiR076840@svn.freebsd.org> From: John Baldwin Date: Fri, 29 May 2009 14:03:34 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org X-SVN-Group: head MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Cc: Subject: svn commit: r193037 - head/sys/kern X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.5 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: Fri, 29 May 2009 14:03:35 -0000 Author: jhb Date: Fri May 29 14:03:34 2009 New Revision: 193037 URL: http://svn.freebsd.org/changeset/base/193037 Log: Remove extra cpu_spinwait() invocations. This should really only be used in tight spin loops, not in these edge cases where we restart a much larger loop only a few times. Reviewed by: attilio Modified: head/sys/kern/kern_mutex.c head/sys/kern/kern_rwlock.c Modified: head/sys/kern/kern_mutex.c ============================================================================== --- head/sys/kern/kern_mutex.c Fri May 29 14:02:45 2009 (r193036) +++ head/sys/kern/kern_mutex.c Fri May 29 14:03:34 2009 (r193037) @@ -393,7 +393,6 @@ _mtx_lock_sleep(struct mtx *m, uintptr_t */ if (v == MTX_UNOWNED) { turnstile_cancel(ts); - cpu_spinwait(); continue; } @@ -408,7 +407,6 @@ _mtx_lock_sleep(struct mtx *m, uintptr_t owner = (struct thread *)(v & ~MTX_FLAGMASK); if (TD_IS_RUNNING(owner)) { turnstile_cancel(ts); - cpu_spinwait(); continue; } #endif @@ -421,7 +419,6 @@ _mtx_lock_sleep(struct mtx *m, uintptr_t if ((v & MTX_CONTESTED) == 0 && !atomic_cmpset_ptr(&m->mtx_lock, v, v | MTX_CONTESTED)) { turnstile_cancel(ts); - cpu_spinwait(); continue; } Modified: head/sys/kern/kern_rwlock.c ============================================================================== --- head/sys/kern/kern_rwlock.c Fri May 29 14:02:45 2009 (r193036) +++ head/sys/kern/kern_rwlock.c Fri May 29 14:03:34 2009 (r193037) @@ -350,7 +350,6 @@ _rw_rlock(struct rwlock *rw, const char (void *)(v + RW_ONE_READER)); break; } - cpu_spinwait(); continue; } lock_profile_obtain_lock_failed(&rw->lock_object, @@ -406,7 +405,6 @@ _rw_rlock(struct rwlock *rw, const char v = rw->rw_lock; if (RW_CAN_READ(v)) { turnstile_cancel(ts); - cpu_spinwait(); continue; } @@ -422,7 +420,6 @@ _rw_rlock(struct rwlock *rw, const char owner = (struct thread *)RW_OWNER(v); if (TD_IS_RUNNING(owner)) { turnstile_cancel(ts); - cpu_spinwait(); continue; } } @@ -443,7 +440,6 @@ _rw_rlock(struct rwlock *rw, const char if (!atomic_cmpset_ptr(&rw->rw_lock, v, v | RW_LOCK_READ_WAITERS)) { turnstile_cancel(ts); - cpu_spinwait(); continue; } if (LOCK_LOG_TEST(&rw->lock_object, 0)) @@ -695,7 +691,6 @@ _rw_wlock_hard(struct rwlock *rw, uintpt if (!(v & RW_LOCK_WRITE_SPINNER)) { if (!atomic_cmpset_ptr(&rw->rw_lock, v, v | RW_LOCK_WRITE_SPINNER)) { - cpu_spinwait(); continue; } } @@ -727,7 +722,6 @@ _rw_wlock_hard(struct rwlock *rw, uintpt owner = (struct thread *)RW_OWNER(v); if (TD_IS_RUNNING(owner)) { turnstile_cancel(ts); - cpu_spinwait(); continue; } } @@ -750,7 +744,6 @@ _rw_wlock_hard(struct rwlock *rw, uintpt break; } turnstile_cancel(ts); - cpu_spinwait(); continue; } /* @@ -762,7 +755,6 @@ _rw_wlock_hard(struct rwlock *rw, uintpt if (!atomic_cmpset_ptr(&rw->rw_lock, v, v | RW_LOCK_WRITE_WAITERS)) { turnstile_cancel(ts); - cpu_spinwait(); continue; } if (LOCK_LOG_TEST(&rw->lock_object, 0))