Module Name: src
Committed By: ad
Date: Sun Apr 19 20:35:29 UTC 2020
Modified Files:
src/sys/kern: kern_condvar.c kern_sleepq.c kern_synch.c kern_timeout.c
kern_turnstile.c sys_lwp.c sys_select.c
src/sys/sys: sleepq.h
Log Message:
Set LW_SINTR earlier so it doesn't pose a problem for doing interruptable
waits with turnstiles (not currently done).
To generate a diff of this commit:
cvs rdiff -u -r1.46 -r1.47 src/sys/kern/kern_condvar.c
cvs rdiff -u -r1.65 -r1.66 src/sys/kern/kern_sleepq.c
cvs rdiff -u -r1.346 -r1.347 src/sys/kern/kern_synch.c
cvs rdiff -u -r1.60 -r1.61 src/sys/kern/kern_timeout.c
cvs rdiff -u -r1.38 -r1.39 src/sys/kern/kern_turnstile.c
cvs rdiff -u -r1.76 -r1.77 src/sys/kern/sys_lwp.c
cvs rdiff -u -r1.53 -r1.54 src/sys/kern/sys_select.c
cvs rdiff -u -r1.28 -r1.29 src/sys/sys/sleepq.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/kern/kern_condvar.c
diff -u src/sys/kern/kern_condvar.c:1.46 src/sys/kern/kern_condvar.c:1.47
--- src/sys/kern/kern_condvar.c:1.46 Mon Apr 13 15:54:45 2020
+++ src/sys/kern/kern_condvar.c Sun Apr 19 20:35:29 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: kern_condvar.c,v 1.46 2020/04/13 15:54:45 maxv Exp $ */
+/* $NetBSD: kern_condvar.c,v 1.47 2020/04/19 20:35:29 ad Exp $ */
/*-
* Copyright (c) 2006, 2007, 2008, 2019, 2020 The NetBSD Foundation, Inc.
@@ -34,7 +34,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_condvar.c,v 1.46 2020/04/13 15:54:45 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_condvar.c,v 1.47 2020/04/19 20:35:29 ad Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -116,7 +116,7 @@ cv_destroy(kcondvar_t *cv)
* condition variable, and increment the number of waiters.
*/
static inline void
-cv_enter(kcondvar_t *cv, kmutex_t *mtx, lwp_t *l)
+cv_enter(kcondvar_t *cv, kmutex_t *mtx, lwp_t *l, bool catch_p)
{
sleepq_t *sq;
kmutex_t *mp;
@@ -129,7 +129,7 @@ cv_enter(kcondvar_t *cv, kmutex_t *mtx,
mp = sleepq_hashlock(cv);
sq = CV_SLEEPQ(cv);
sleepq_enter(sq, l, mp);
- sleepq_enqueue(sq, cv, CV_WMESG(cv), &cv_syncobj);
+ sleepq_enqueue(sq, cv, CV_WMESG(cv), &cv_syncobj, catch_p);
mutex_exit(mtx);
KASSERT(cv_has_waiters(cv));
}
@@ -169,7 +169,7 @@ cv_wait(kcondvar_t *cv, kmutex_t *mtx)
KASSERT(mutex_owned(mtx));
- cv_enter(cv, mtx, l);
+ cv_enter(cv, mtx, l, false);
(void)sleepq_block(0, false);
mutex_enter(mtx);
}
@@ -190,7 +190,7 @@ cv_wait_sig(kcondvar_t *cv, kmutex_t *mt
KASSERT(mutex_owned(mtx));
- cv_enter(cv, mtx, l);
+ cv_enter(cv, mtx, l, true);
error = sleepq_block(0, true);
mutex_enter(mtx);
return error;
@@ -213,7 +213,7 @@ cv_timedwait(kcondvar_t *cv, kmutex_t *m
KASSERT(mutex_owned(mtx));
- cv_enter(cv, mtx, l);
+ cv_enter(cv, mtx, l, false);
error = sleepq_block(timo, false);
mutex_enter(mtx);
return error;
@@ -238,7 +238,7 @@ cv_timedwait_sig(kcondvar_t *cv, kmutex_
KASSERT(mutex_owned(mtx));
- cv_enter(cv, mtx, l);
+ cv_enter(cv, mtx, l, true);
error = sleepq_block(timo, true);
mutex_enter(mtx);
return error;
Index: src/sys/kern/kern_sleepq.c
diff -u src/sys/kern/kern_sleepq.c:1.65 src/sys/kern/kern_sleepq.c:1.66
--- src/sys/kern/kern_sleepq.c:1.65 Mon Apr 13 15:54:45 2020
+++ src/sys/kern/kern_sleepq.c Sun Apr 19 20:35:29 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: kern_sleepq.c,v 1.65 2020/04/13 15:54:45 maxv Exp $ */
+/* $NetBSD: kern_sleepq.c,v 1.66 2020/04/19 20:35:29 ad Exp $ */
/*-
* Copyright (c) 2006, 2007, 2008, 2009, 2019, 2020 The NetBSD Foundation, Inc.
@@ -35,7 +35,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_sleepq.c,v 1.65 2020/04/13 15:54:45 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_sleepq.c,v 1.66 2020/04/19 20:35:29 ad Exp $");
#include <sys/param.h>
#include <sys/kernel.h>
@@ -210,13 +210,15 @@ sleepq_insert(sleepq_t *sq, lwp_t *l, sy
* lock) must have be released (see sleeptab_lookup(), sleepq_enter()).
*/
void
-sleepq_enqueue(sleepq_t *sq, wchan_t wchan, const char *wmesg, syncobj_t *sobj)
+sleepq_enqueue(sleepq_t *sq, wchan_t wchan, const char *wmesg, syncobj_t *sobj,
+ bool catch_p)
{
lwp_t *l = curlwp;
KASSERT(lwp_locked(l, NULL));
KASSERT(l->l_stat == LSONPROC);
KASSERT(l->l_wchan == NULL && l->l_sleepq == NULL);
+ KASSERT((l->l_flag & LW_SINTR) == 0);
l->l_syncobj = sobj;
l->l_wchan = wchan;
@@ -224,6 +226,8 @@ sleepq_enqueue(sleepq_t *sq, wchan_t wch
l->l_wmesg = wmesg;
l->l_slptime = 0;
l->l_stat = LSSLEEP;
+ if (catch_p)
+ l->l_flag |= LW_SINTR;
sleepq_insert(sq, l, sobj);
@@ -254,13 +258,9 @@ sleepq_block(int timo, bool catch_p)
/*
* If sleeping interruptably, check for pending signals, exits or
- * core dump events. XXX The set of LW_SINTR here assumes no unlock
- * between sleepq_enqueue() and sleepq_block(). Unlock between
- * those only happens with turnstiles, which never set catch_p.
- * Ugly but safe.
+ * core dump events.
*/
if (catch_p) {
- l->l_flag |= LW_SINTR;
if ((l->l_flag & (LW_CANCELLED|LW_WEXIT|LW_WCORE)) != 0) {
l->l_flag &= ~LW_CANCELLED;
error = EINTR;
@@ -273,6 +273,13 @@ sleepq_block(int timo, bool catch_p)
/* lwp_unsleep() will release the lock */
lwp_unsleep(l, true);
} else {
+ /*
+ * The LWP may have already been awoken if the caller
+ * dropped the sleep queue lock between sleepq_enqueue() and
+ * sleepq_block(). If that happends l_stat will be LSONPROC
+ * and mi_switch() will treat this as a preemption. No need
+ * to do anything special here.
+ */
if (timo) {
l->l_flag &= ~LW_STIMO;
callout_schedule(&l->l_timeout_ch, timo);
Index: src/sys/kern/kern_synch.c
diff -u src/sys/kern/kern_synch.c:1.346 src/sys/kern/kern_synch.c:1.347
--- src/sys/kern/kern_synch.c:1.346 Sat Apr 4 20:21:53 2020
+++ src/sys/kern/kern_synch.c Sun Apr 19 20:35:29 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: kern_synch.c,v 1.346 2020/04/04 20:21:53 ad Exp $ */
+/* $NetBSD: kern_synch.c,v 1.347 2020/04/19 20:35:29 ad Exp $ */
/*-
* Copyright (c) 1999, 2000, 2004, 2006, 2007, 2008, 2009, 2019, 2020
@@ -69,7 +69,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_synch.c,v 1.346 2020/04/04 20:21:53 ad Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_synch.c,v 1.347 2020/04/19 20:35:29 ad Exp $");
#include "opt_kstack.h"
#include "opt_dtrace.h"
@@ -173,6 +173,7 @@ tsleep(wchan_t ident, pri_t priority, co
struct lwp *l = curlwp;
sleepq_t *sq;
kmutex_t *mp;
+ bool catch_p;
KASSERT((l->l_pflag & LP_INTR) == 0);
KASSERT(ident != &lbolt);
@@ -183,10 +184,11 @@ tsleep(wchan_t ident, pri_t priority, co
}
l->l_kpriority = true;
+ catch_p = priority & PCATCH;
sq = sleeptab_lookup(&sleeptab, ident, &mp);
sleepq_enter(sq, l, mp);
- sleepq_enqueue(sq, ident, wmesg, &sleep_syncobj);
- return sleepq_block(timo, priority & PCATCH);
+ sleepq_enqueue(sq, ident, wmesg, &sleep_syncobj, catch_p);
+ return sleepq_block(timo, catch_p);
}
int
@@ -196,6 +198,7 @@ mtsleep(wchan_t ident, pri_t priority, c
struct lwp *l = curlwp;
sleepq_t *sq;
kmutex_t *mp;
+ bool catch_p;
int error;
KASSERT((l->l_pflag & LP_INTR) == 0);
@@ -207,11 +210,12 @@ mtsleep(wchan_t ident, pri_t priority, c
}
l->l_kpriority = true;
+ catch_p = priority & PCATCH;
sq = sleeptab_lookup(&sleeptab, ident, &mp);
sleepq_enter(sq, l, mp);
- sleepq_enqueue(sq, ident, wmesg, &sleep_syncobj);
+ sleepq_enqueue(sq, ident, wmesg, &sleep_syncobj, catch_p);
mutex_exit(mtx);
- error = sleepq_block(timo, priority & PCATCH);
+ error = sleepq_block(timo, catch_p);
if ((priority & PNORELOCK) == 0)
mutex_enter(mtx);
@@ -238,7 +242,7 @@ kpause(const char *wmesg, bool intr, int
l->l_kpriority = true;
lwp_lock(l);
KERNEL_UNLOCK_ALL(NULL, &l->l_biglocks);
- sleepq_enqueue(NULL, l, wmesg, &kpause_syncobj);
+ sleepq_enqueue(NULL, l, wmesg, &kpause_syncobj, intr);
error = sleepq_block(timo, intr);
if (mtx != NULL)
mutex_enter(mtx);
Index: src/sys/kern/kern_timeout.c
diff -u src/sys/kern/kern_timeout.c:1.60 src/sys/kern/kern_timeout.c:1.61
--- src/sys/kern/kern_timeout.c:1.60 Mon Apr 13 15:54:45 2020
+++ src/sys/kern/kern_timeout.c Sun Apr 19 20:35:29 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: kern_timeout.c,v 1.60 2020/04/13 15:54:45 maxv Exp $ */
+/* $NetBSD: kern_timeout.c,v 1.61 2020/04/19 20:35:29 ad Exp $ */
/*-
* Copyright (c) 2003, 2006, 2007, 2008, 2009, 2019 The NetBSD Foundation, Inc.
@@ -59,7 +59,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_timeout.c,v 1.60 2020/04/13 15:54:45 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_timeout.c,v 1.61 2020/04/19 20:35:29 ad Exp $");
/*
* Timeouts are kept in a hierarchical timing wheel. The c_time is the
@@ -539,7 +539,7 @@ callout_wait(callout_impl_t *c, void *in
l->l_kpriority = true;
sleepq_enter(&cc->cc_sleepq, l, cc->cc_lock);
sleepq_enqueue(&cc->cc_sleepq, cc, "callout",
- &sleep_syncobj);
+ &sleep_syncobj, false);
sleepq_block(0, false);
}
Index: src/sys/kern/kern_turnstile.c
diff -u src/sys/kern/kern_turnstile.c:1.38 src/sys/kern/kern_turnstile.c:1.39
--- src/sys/kern/kern_turnstile.c:1.38 Thu Mar 26 22:43:19 2020
+++ src/sys/kern/kern_turnstile.c Sun Apr 19 20:35:29 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: kern_turnstile.c,v 1.38 2020/03/26 22:43:19 ad Exp $ */
+/* $NetBSD: kern_turnstile.c,v 1.39 2020/04/19 20:35:29 ad Exp $ */
/*-
* Copyright (c) 2002, 2006, 2007, 2009, 2019, 2020
@@ -61,7 +61,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_turnstile.c,v 1.38 2020/03/26 22:43:19 ad Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_turnstile.c,v 1.39 2020/04/19 20:35:29 ad Exp $");
#include <sys/param.h>
#include <sys/lockdebug.h>
@@ -429,7 +429,7 @@ turnstile_block(turnstile_t *ts, int q,
obase = l->l_kpribase;
if (obase < PRI_KTHREAD)
l->l_kpribase = PRI_KTHREAD;
- sleepq_enqueue(sq, obj, "tstile", sobj);
+ sleepq_enqueue(sq, obj, "tstile", sobj, false);
/*
* Disable preemption across this entire block, as we may drop
Index: src/sys/kern/sys_lwp.c
diff -u src/sys/kern/sys_lwp.c:1.76 src/sys/kern/sys_lwp.c:1.77
--- src/sys/kern/sys_lwp.c:1.76 Sat Apr 4 20:20:12 2020
+++ src/sys/kern/sys_lwp.c Sun Apr 19 20:35:29 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: sys_lwp.c,v 1.76 2020/04/04 20:20:12 thorpej Exp $ */
+/* $NetBSD: sys_lwp.c,v 1.77 2020/04/19 20:35:29 ad Exp $ */
/*-
* Copyright (c) 2001, 2006, 2007, 2008, 2019, 2020 The NetBSD Foundation, Inc.
@@ -35,7 +35,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: sys_lwp.c,v 1.76 2020/04/04 20:20:12 thorpej Exp $");
+__KERNEL_RCSID(0, "$NetBSD: sys_lwp.c,v 1.77 2020/04/19 20:35:29 ad Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -542,7 +542,7 @@ lwp_park(clockid_t clock_id, int flags,
return EALREADY;
}
l->l_biglocks = 0;
- sleepq_enqueue(NULL, l, "parked", &lwp_park_syncobj);
+ sleepq_enqueue(NULL, l, "parked", &lwp_park_syncobj, true);
error = sleepq_block(timo, true);
switch (error) {
case EWOULDBLOCK:
Index: src/sys/kern/sys_select.c
diff -u src/sys/kern/sys_select.c:1.53 src/sys/kern/sys_select.c:1.54
--- src/sys/kern/sys_select.c:1.53 Thu Mar 26 19:46:42 2020
+++ src/sys/kern/sys_select.c Sun Apr 19 20:35:29 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: sys_select.c,v 1.53 2020/03/26 19:46:42 ad Exp $ */
+/* $NetBSD: sys_select.c,v 1.54 2020/04/19 20:35:29 ad Exp $ */
/*-
* Copyright (c) 2007, 2008, 2009, 2010, 2019, 2020 The NetBSD Foundation, Inc.
@@ -84,7 +84,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: sys_select.c,v 1.53 2020/03/26 19:46:42 ad Exp $");
+__KERNEL_RCSID(0, "$NetBSD: sys_select.c,v 1.54 2020/04/19 20:35:29 ad Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -321,7 +321,7 @@ state_check:
l->l_selflag = SEL_BLOCKING;
l->l_kpriority = true;
sleepq_enter(&sc->sc_sleepq, l, lock);
- sleepq_enqueue(&sc->sc_sleepq, sc, opname, &select_sobj);
+ sleepq_enqueue(&sc->sc_sleepq, sc, opname, &select_sobj, true);
error = sleepq_block(timo, true);
if (error != 0) {
break;
Index: src/sys/sys/sleepq.h
diff -u src/sys/sys/sleepq.h:1.28 src/sys/sys/sleepq.h:1.29
--- src/sys/sys/sleepq.h:1.28 Thu Mar 26 19:46:42 2020
+++ src/sys/sys/sleepq.h Sun Apr 19 20:35:29 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: sleepq.h,v 1.28 2020/03/26 19:46:42 ad Exp $ */
+/* $NetBSD: sleepq.h,v 1.29 2020/04/19 20:35:29 ad Exp $ */
/*-
* Copyright (c) 2002, 2006, 2007, 2008, 2009, 2019, 2020
@@ -60,7 +60,8 @@ typedef struct sleeptab {
void sleepq_init(sleepq_t *);
void sleepq_remove(sleepq_t *, lwp_t *);
-void sleepq_enqueue(sleepq_t *, wchan_t, const char *, struct syncobj *);
+void sleepq_enqueue(sleepq_t *, wchan_t, const char *, struct syncobj *,
+ bool);
void sleepq_unsleep(lwp_t *, bool);
void sleepq_timeout(void *);
void sleepq_wake(sleepq_t *, wchan_t, u_int, kmutex_t *);
