Module Name: src
Committed By: pho
Date: Tue Jun 27 01:17:43 UTC 2023
Modified Files:
src/sys/kern: kern_timeout.c
Log Message:
callout(9): Tidy up the condition for "callout is running on another LWP"
No functional changes.
To generate a diff of this commit:
cvs rdiff -u -r1.74 -r1.75 src/sys/kern/kern_timeout.c
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_timeout.c
diff -u src/sys/kern/kern_timeout.c:1.74 src/sys/kern/kern_timeout.c:1.75
--- src/sys/kern/kern_timeout.c:1.74 Tue Jun 27 01:15:22 2023
+++ src/sys/kern/kern_timeout.c Tue Jun 27 01:17:43 2023
@@ -1,4 +1,4 @@
-/* $NetBSD: kern_timeout.c,v 1.74 2023/06/27 01:15:22 pho Exp $ */
+/* $NetBSD: kern_timeout.c,v 1.75 2023/06/27 01:17:43 pho 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 1.74 2023/06/27 01:15:22 pho Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_timeout.c,v 1.75 2023/06/27 01:17:43 pho Exp $");
/*
* Timeouts are kept in a hierarchical timing wheel. The c_time is the
@@ -263,6 +263,17 @@ callout_lock(callout_impl_t *c)
}
/*
+ * Check if the callout is currently running on an LWP that isn't curlwp.
+ */
+static inline bool
+callout_running_somewhere_else(callout_impl_t *c, struct callout_cpu *cc)
+{
+ KASSERT(c->c_cpu == cc);
+
+ return cc->cc_active == c && cc->cc_lwp != curlwp;
+}
+
+/*
* callout_startup:
*
* Initialize the callout facility, called at system startup time.
@@ -378,7 +389,7 @@ callout_destroy(callout_t *cs)
KASSERTMSG((c->c_flags & CALLOUT_PENDING) == 0,
"pending callout %p: c_func (%p) c_flags (%#x) destroyed from %p",
c, c->c_func, c->c_flags, __builtin_return_address(0));
- KASSERTMSG(c->c_cpu->cc_lwp == curlwp || c->c_cpu->cc_active != c,
+ KASSERTMSG(!callout_running_somewhere_else(c, c->c_cpu),
"running callout %p: c_func (%p) c_flags (%#x) destroyed from %p",
c, c->c_func, c->c_flags, __builtin_return_address(0));
c->c_magic = 0;
@@ -542,7 +553,6 @@ callout_halt(callout_t *cs, void *interl
{
callout_impl_t *c = (callout_impl_t *)cs;
kmutex_t *lock;
- struct callout_cpu *cc;
KASSERT(c->c_magic == CALLOUT_MAGIC);
KASSERT(!cpu_intr_p());
@@ -555,8 +565,7 @@ callout_halt(callout_t *cs, void *interl
if ((c->c_flags & CALLOUT_PENDING) != 0)
CIRCQ_REMOVE(&c->c_list);
c->c_flags &= ~(CALLOUT_PENDING|CALLOUT_FIRED);
- cc = c->c_cpu;
- if (__predict_false(cc->cc_active == c && cc->cc_lwp != curlwp)) {
+ if (__predict_false(callout_running_somewhere_else(c, c->c_cpu))) {
callout_wait(c, interlock, lock);
return true;
}
@@ -592,7 +601,7 @@ callout_wait(callout_impl_t *c, void *in
* - the callout itself has called callout_halt() (nice!)
*/
cc = c->c_cpu;
- if (__predict_true(cc->cc_active != c || cc->cc_lwp == l))
+ if (__predict_true(!callout_running_somewhere_else(c, cc)))
break;
/* It's running - need to wait for it to complete. */
