Module Name: src
Committed By: riastradh
Date: Mon May 4 18:23:37 UTC 2020
Modified Files:
src/sys/kern: kern_condvar.c subr_time.c
src/sys/sys: timevar.h
Log Message:
New timedwaitclock_setup.
C99 initializers would have been nice, but part of the struct is
explicit parameters and part of the struct is implicit state, and
-Wmissing-field-initializers can't discriminate between them
(although for some reason it doesn't always fire!).
Instead, just do:
struct timedwaitclock T;
timedwaitclock_setup(&T, timeout, clockid, flags, epsilon);
while (...) {
error = timedwaitclock_begin(&T, &timo);
if (error)
...
error = waitwhatever(timo);
timedwaitclock_end(&T);
...
}
To generate a diff of this commit:
cvs rdiff -u -r1.50 -r1.51 src/sys/kern/kern_condvar.c
cvs rdiff -u -r1.22 -r1.23 src/sys/kern/subr_time.c
cvs rdiff -u -r1.42 -r1.43 src/sys/sys/timevar.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:1.50 src/sys/kern/kern_condvar.c:1.51
--- src/sys/kern/kern_condvar.c:1.50 Sun May 3 17:36:33 2020
+++ src/sys/kern/kern_condvar.c Mon May 4 18:23:37 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: kern_condvar.c,v 1.50 2020/05/03 17:36:33 thorpej Exp $ */
+/* $NetBSD: kern_condvar.c,v 1.51 2020/05/04 18:23:37 riastradh 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 1.50 2020/05/03 17:36:33 thorpej Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_condvar.c,v 1.51 2020/05/04 18:23:37 riastradh Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -261,12 +261,7 @@ int
cv_timedwaitclock(kcondvar_t *cv, kmutex_t *mtx, struct timespec *timeout,
clockid_t clockid, int flags, const struct bintime *epsilon)
{
- struct timedwaitclock T = {
- .timeout = timeout,
- .clockid = clockid,
- .flags = flags,
- .epsilon = epsilon,
- };
+ struct timedwaitclock T;
int timo;
int error;
@@ -275,6 +270,7 @@ cv_timedwaitclock(kcondvar_t *cv, kmutex
return 0;
}
+ timedwaitclock_setup(&T, timeout, clockid, flags, epsilon);
error = timedwaitclock_begin(&T, &timo);
if (error)
return error;
@@ -301,18 +297,14 @@ int
cv_timedwaitclock_sig(kcondvar_t *cv, kmutex_t *mtx, struct timespec *timeout,
clockid_t clockid, int flags, const struct bintime *epsilon)
{
- struct timedwaitclock T = {
- .timeout = timeout,
- .clockid = clockid,
- .flags = flags,
- .epsilon = epsilon,
- };
+ struct timedwaitclock T;
int timo;
int error;
if (timeout == NULL)
return cv_wait_sig(cv, mtx);
+ timedwaitclock_setup(&T, timeout, clockid, flags, epsilon);
error = timedwaitclock_begin(&T, &timo);
if (error)
return error;
Index: src/sys/kern/subr_time.c
diff -u src/sys/kern/subr_time.c:1.22 src/sys/kern/subr_time.c:1.23
--- src/sys/kern/subr_time.c:1.22 Sun May 3 17:36:33 2020
+++ src/sys/kern/subr_time.c Mon May 4 18:23:37 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: subr_time.c,v 1.22 2020/05/03 17:36:33 thorpej Exp $ */
+/* $NetBSD: subr_time.c,v 1.23 2020/05/04 18:23:37 riastradh Exp $ */
/*
* Copyright (c) 1982, 1986, 1989, 1993
@@ -33,7 +33,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: subr_time.c,v 1.22 2020/05/03 17:36:33 thorpej Exp $");
+__KERNEL_RCSID(0, "$NetBSD: subr_time.c,v 1.23 2020/05/04 18:23:37 riastradh Exp $");
#include <sys/param.h>
#include <sys/kernel.h>
@@ -355,6 +355,38 @@ ts2timo(clockid_t clock_id, int flags, s
return 0;
}
+/*
+ * timedwaitclock_setup(T, timeout, clockid, flags, epsilon)
+ *
+ * Initialize state for a timedwaitclock, to be used subsequently
+ * with timedwaitclock_begin/end, possibly many times in a row.
+ *
+ * No cleanup action required at the end; the caller-allocated
+ * (typically stack-allocated) timedwaitclock just holds
+ * parameters and a little state for timedwaitclock_begin/end.
+ */
+void
+timedwaitclock_setup(struct timedwaitclock *T, struct timespec *timeout,
+ clockid_t clockid, int flags, const struct bintime *epsilon)
+{
+
+ memset(T, 0, sizeof(*T));
+ T->timeout = timeout;
+ T->clockid = clockid;
+ T->flags = flags;
+ T->epsilon = epsilon;
+ T->starttime = (struct timespec){0,0};
+}
+
+/*
+ * timedwaitclock_begin(T, timo)
+ *
+ * Decide how many ticks to wait for the timedwaitclock T and
+ * store it in *timo. Keep state for timedwaitclock_end. May
+ * fail with EINVAL if the specified timeout is invalid, or if the
+ * specified clock fails. Fails with ETIMEDOUT if there is no
+ * time left to wait.
+ */
int
timedwaitclock_begin(struct timedwaitclock *T, int *timo)
{
@@ -406,6 +438,14 @@ timedwaitclock_begin(struct timedwaitclo
return 0;
}
+/*
+ * timedwaitclock_end(T)
+ *
+ * If the timedwaitclock T was relative, update the caller's
+ * original timeout to reflect how much time is left, or zero if
+ * there is no time left or if the clock has gone bad, so that the
+ * next timedwaitclock_begin will immediately time out.
+ */
void
timedwaitclock_end(struct timedwaitclock *T)
{
Index: src/sys/sys/timevar.h
diff -u src/sys/sys/timevar.h:1.42 src/sys/sys/timevar.h:1.43
--- src/sys/sys/timevar.h:1.42 Sun May 3 17:36:33 2020
+++ src/sys/sys/timevar.h Mon May 4 18:23:37 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: timevar.h,v 1.42 2020/05/03 17:36:33 thorpej Exp $ */
+/* $NetBSD: timevar.h,v 1.43 2020/05/04 18:23:37 riastradh Exp $ */
/*
* Copyright (c) 2005, 2008, The NetBSD Foundation.
@@ -200,6 +200,8 @@ void time_init(void);
void time_init2(void);
bool time_wraps(struct timespec *, struct timespec *);
+void timedwaitclock_setup(struct timedwaitclock *, struct timespec *,
+ clockid_t, int, const struct bintime *);
int timedwaitclock_begin(struct timedwaitclock *, int *);
void timedwaitclock_end(struct timedwaitclock *);
