Module Name: src
Committed By: thorpej
Date: Sat Apr 3 15:29:02 UTC 2021
Modified Files:
src/sys/arch/alpha/alpha: pmap.c
Log Message:
Slight tweak to last: Our IPL gets raised to IPL_SCHED by simply *trying*
to acquire the pmap activation lock, regardless of whether or not that was
successful. So, in addition to remember if we acquired it, also remember
if we tried, and drop back to IPL_VM if so.
To generate a diff of this commit:
cvs rdiff -u -r1.275 -r1.276 src/sys/arch/alpha/alpha/pmap.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/arch/alpha/alpha/pmap.c
diff -u src/sys/arch/alpha/alpha/pmap.c:1.275 src/sys/arch/alpha/alpha/pmap.c:1.276
--- src/sys/arch/alpha/alpha/pmap.c:1.275 Sat Apr 3 14:56:13 2021
+++ src/sys/arch/alpha/alpha/pmap.c Sat Apr 3 15:29:02 2021
@@ -1,4 +1,4 @@
-/* $NetBSD: pmap.c,v 1.275 2021/04/03 14:56:13 thorpej Exp $ */
+/* $NetBSD: pmap.c,v 1.276 2021/04/03 15:29:02 thorpej Exp $ */
/*-
* Copyright (c) 1998, 1999, 2000, 2001, 2007, 2008, 2020
@@ -135,7 +135,7 @@
#include <sys/cdefs.h> /* RCS ID & Copyright macro defns */
-__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.275 2021/04/03 14:56:13 thorpej Exp $");
+__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.276 2021/04/03 15:29:02 thorpej Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -915,7 +915,7 @@ pmap_tlb_shootnow(const struct pmap_tlb_
const struct cpu_info *ci = curcpu();
const u_long this_cpu = 1UL << ci->ci_cpuid;
u_long active_cpus;
- bool activation_locked;
+ bool activation_locked, activation_lock_tried;
/*
* Figure out who to notify. If it's for the kernel or
@@ -929,6 +929,7 @@ pmap_tlb_shootnow(const struct pmap_tlb_
if (TLB_CTX_FLAGS(tlbctx) & (TLB_CTX_F_ASM | TLB_CTX_F_MULTI)) {
active_cpus = pmap_all_cpus();
activation_locked = false;
+ activation_lock_tried = false;
} else {
KASSERT(tlbctx->t_pmap != NULL);
activation_locked = PMAP_ACT_TRYLOCK(tlbctx->t_pmap);
@@ -938,6 +939,7 @@ pmap_tlb_shootnow(const struct pmap_tlb_
TLB_COUNT(shootnow_over_notify);
active_cpus = pmap_all_cpus();
}
+ activation_lock_tried = true;
}
#if defined(MULTIPROCESSOR)
@@ -959,14 +961,17 @@ pmap_tlb_shootnow(const struct pmap_tlb_
* Now that the remotes have been notified, release the
* activation lock.
*/
- if (activation_locked) {
- KASSERT(tlbctx->t_pmap != NULL);
- PMAP_ACT_UNLOCK(tlbctx->t_pmap);
+ if (activation_lock_tried) {
+ if (activation_locked) {
+ KASSERT(tlbctx->t_pmap != NULL);
+ PMAP_ACT_UNLOCK(tlbctx->t_pmap);
+ }
/*
- * When we acquired the activation lock, we
- * raised IPL to IPL_SCHED, which blocks out
- * IPIs. Force our IPL back down to IPL_VM
- * so that we can receive IPIs.
+ * When we tried to acquire the activation lock, we
+ * raised IPL to IPL_SCHED (even if we ultimately
+ * failed to acquire the lock), which blocks out IPIs.
+ * Force our IPL back down to IPL_VM so that we can
+ * receive IPIs.
*/
alpha_pal_swpipl(IPL_VM);
}
