[src/trunk]: src/sys use lockstatus() instead of L_BIGLOCK to check if we're ...

[yamt <yamt%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/c3a5e2f1240e
branches:  trunk
changeset: 566721:c3a5e2f1240e
user:      yamt <yamt%NetBSD.org@localhost>
date:      Tue May 18 11:59:11 2004 +0000

description:
use lockstatus() instead of L_BIGLOCK to check if we're holding a biglock.
fix PR/25595.

diffstat:

 sys/kern/kern_lock.c  |  27 +++++++++++++++++++++++----
 sys/kern/kern_sa.c    |   6 +++---
 sys/kern/kern_synch.c |  18 +++++-------------
 sys/sys/lwp.h         |   3 +--
 sys/sys/systm.h       |   8 +++++++-
 5 files changed, 39 insertions(+), 23 deletions(-)

diffs (194 lines):

diff -r 25a37e9a65dd -r c3a5e2f1240e sys/kern/kern_lock.c
--- a/sys/kern/kern_lock.c      Tue May 18 11:55:59 2004 +0000
+++ b/sys/kern/kern_lock.c      Tue May 18 11:59:11 2004 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: kern_lock.c,v 1.76 2004/05/18 11:55:59 yamt Exp $      */
+/*     $NetBSD: kern_lock.c,v 1.77 2004/05/18 11:59:11 yamt Exp $      */
 
 /*-
  * Copyright (c) 1999, 2000 The NetBSD Foundation, Inc.
@@ -76,7 +76,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_lock.c,v 1.76 2004/05/18 11:55:59 yamt Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_lock.c,v 1.77 2004/05/18 11:59:11 yamt Exp $");
 
 #include "opt_multiprocessor.h"
 #include "opt_lockdebug.h"
@@ -1371,14 +1371,33 @@
 
        SCHED_ASSERT_UNLOCKED();
        spinlockmgr(&kernel_lock, LK_EXCLUSIVE, 0);
-       l->l_flag |= L_BIGLOCK;
 }
 
 void
 _kernel_proc_unlock(struct lwp *l)
 {
 
-       l->l_flag &= ~L_BIGLOCK;
        spinlockmgr(&kernel_lock, LK_RELEASE, 0);
 }
+
+int
+_kernel_lock_release_all()
+{
+       int hold_count;
+
+       if (lockstatus(&kernel_lock) == LK_EXCLUSIVE)
+               hold_count = spinlock_release_all(&kernel_lock);
+       else
+               hold_count = 0;
+
+       return hold_count;
+}
+
+void
+_kernel_lock_acquire_count(int hold_count)
+{
+
+       if (hold_count != 0)
+               spinlock_acquire_count(&kernel_lock, hold_count);
+}
 #endif /* MULTIPROCESSOR */
diff -r 25a37e9a65dd -r c3a5e2f1240e sys/kern/kern_sa.c
--- a/sys/kern/kern_sa.c        Tue May 18 11:55:59 2004 +0000
+++ b/sys/kern/kern_sa.c        Tue May 18 11:59:11 2004 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: kern_sa.c,v 1.50 2004/03/27 00:49:47 petrov Exp $      */
+/*     $NetBSD: kern_sa.c,v 1.51 2004/05/18 11:59:11 yamt Exp $        */
 
 /*-
  * Copyright (c) 2001 The NetBSD Foundation, Inc.
@@ -37,7 +37,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_sa.c,v 1.50 2004/03/27 00:49:47 petrov Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_sa.c,v 1.51 2004/05/18 11:59:11 yamt Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -622,7 +622,7 @@
        int ret;
 
 #if defined(MULTIPROCESSOR)
-       KDASSERT(l->l_flag & L_BIGLOCK);
+       KDASSERT(lockstatus(&kernel_lock) == LK_EXCLUSIVE);
 #endif
 
        if (vp->savp_lwp != l) {
diff -r 25a37e9a65dd -r c3a5e2f1240e sys/kern/kern_synch.c
--- a/sys/kern/kern_synch.c     Tue May 18 11:55:59 2004 +0000
+++ b/sys/kern/kern_synch.c     Tue May 18 11:59:11 2004 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: kern_synch.c,v 1.143 2004/05/12 20:13:58 yamt Exp $    */
+/*     $NetBSD: kern_synch.c,v 1.144 2004/05/18 11:59:11 yamt Exp $    */
 
 /*-
  * Copyright (c) 1999, 2000 The NetBSD Foundation, Inc.
@@ -74,7 +74,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_synch.c,v 1.143 2004/05/12 20:13:58 yamt Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_synch.c,v 1.144 2004/05/18 11:59:11 yamt Exp $");
 
 #include "opt_ddb.h"
 #include "opt_ktrace.h"
@@ -840,23 +840,18 @@
        struct rlimit *rlim;
        long s, u;
        struct timeval tv;
-#if defined(MULTIPROCESSOR)
-       int hold_count = 0;     /* XXX: gcc */
-#endif
+       int hold_count;
        struct proc *p = l->l_proc;
        int retval;
 
        SCHED_ASSERT_LOCKED();
 
-#if defined(MULTIPROCESSOR)
        /*
         * Release the kernel_lock, as we are about to yield the CPU.
         * The scheduler lock is still held until cpu_switch()
         * selects a new process and removes it from the run queue.
         */
-       if (l->l_flag & L_BIGLOCK)
-               hold_count = spinlock_release_all(&kernel_lock);
-#endif
+       hold_count = KERNEL_LOCK_RELEASE_ALL();
 
        KDASSERT(l->l_cpu != NULL);
        KDASSERT(l->l_cpu == curcpu());
@@ -967,15 +962,12 @@
        KDASSERT(l->l_cpu == curcpu());
        microtime(&l->l_cpu->ci_schedstate.spc_runtime);
 
-#if defined(MULTIPROCESSOR)
        /*
         * Reacquire the kernel_lock now.  We do this after we've
         * released the scheduler lock to avoid deadlock, and before
         * we reacquire the interlock.
         */
-       if (l->l_flag & L_BIGLOCK)
-               spinlock_acquire_count(&kernel_lock, hold_count);
-#endif
+       KERNEL_LOCK_ACQUIRE_COUNT(hold_count);
 
        return retval;
 }
diff -r 25a37e9a65dd -r c3a5e2f1240e sys/sys/lwp.h
--- a/sys/sys/lwp.h     Tue May 18 11:55:59 2004 +0000
+++ b/sys/sys/lwp.h     Tue May 18 11:59:11 2004 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: lwp.h,v 1.21 2004/03/14 01:08:47 cl Exp $      */
+/*     $NetBSD: lwp.h,v 1.22 2004/05/18 11:59:11 yamt Exp $    */
 
 /*-
  * Copyright (c) 2001 The NetBSD Foundation, Inc.
@@ -109,7 +109,6 @@
 #define        L_SINTR         0x00080 /* Sleep is interruptible. */
 #define        L_TIMEOUT       0x00400 /* Timing out during sleep. */
 #define        L_PROCEXIT      0x00800 /* In process exit, l_proc no longer valid */
-#define        L_BIGLOCK       0x80000 /* LWP needs kernel "big lock" to run */
 #define        L_SA            0x100000 /* Scheduler activations LWP */
 #define        L_SA_UPCALL     0x200000 /* SA upcall is pending */
 #define        L_SA_BLOCKING   0x400000 /* Blocking in tsleep() */
diff -r 25a37e9a65dd -r c3a5e2f1240e sys/sys/systm.h
--- a/sys/sys/systm.h   Tue May 18 11:55:59 2004 +0000
+++ b/sys/sys/systm.h   Tue May 18 11:59:11 2004 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: systm.h,v 1.171 2004/04/21 20:31:50 matt Exp $ */
+/*     $NetBSD: systm.h,v 1.172 2004/05/18 11:59:11 yamt Exp $ */
 
 /*-
  * Copyright (c) 1982, 1988, 1991, 1993
@@ -442,12 +442,16 @@
 void   _kernel_unlock(void);
 void   _kernel_proc_lock(struct lwp *);
 void   _kernel_proc_unlock(struct lwp *);
+int    _kernel_lock_release_all(void);
+void   _kernel_lock_acquire_count(int);
 
 #define        KERNEL_LOCK_INIT()              _kernel_lock_init()
 #define        KERNEL_LOCK(flag)               _kernel_lock((flag))
 #define        KERNEL_UNLOCK()                 _kernel_unlock()
 #define        KERNEL_PROC_LOCK(l)             _kernel_proc_lock((l))
 #define        KERNEL_PROC_UNLOCK(l)           _kernel_proc_unlock((l))
+#define        KERNEL_LOCK_RELEASE_ALL()       _kernel_lock_release_all()
+#define        KERNEL_LOCK_ACQUIRE_COUNT(count) _kernel_lock_acquire_count(count)
 
 #else /* ! MULTIPROCESSOR */
 
@@ -456,6 +460,8 @@
 #define        KERNEL_UNLOCK()                 /* nothing */
 #define        KERNEL_PROC_LOCK(l)             /* nothing */
 #define        KERNEL_PROC_UNLOCK(l)           /* nothing */
+#define        KERNEL_LOCK_RELEASE_ALL()       (0)
+#define        KERNEL_LOCK_ACQUIRE_COUNT(count) /* nothing */
 
 #endif /* MULTIPROCESSOR */