Module Name: src
Committed By: mrg
Date: Sun Mar 21 22:38:08 UTC 2010
Modified Files:
src/sys/arch/sparc64/sparc64: pmap.c
Log Message:
since pmap_activate/pmap_deactivate need to not block, but the rest of
pmap is OK, add a new IPL_VM pmap_ctx_lock that is held while allocating
or freeing a context, and revert pmap_lock back to IPL_NONE.
i considered a per-cpu context lock, but that would require locking
each active CPUs lock in turn in pmap_remove_all() and pmap_destroy().
thanks to ad for explaining how these parts interact.
To generate a diff of this commit:
cvs rdiff -u -r1.260 -r1.261 src/sys/arch/sparc64/sparc64/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/sparc64/sparc64/pmap.c
diff -u src/sys/arch/sparc64/sparc64/pmap.c:1.260 src/sys/arch/sparc64/sparc64/pmap.c:1.261
--- src/sys/arch/sparc64/sparc64/pmap.c:1.260 Sat Mar 20 20:36:23 2010
+++ src/sys/arch/sparc64/sparc64/pmap.c Sun Mar 21 22:38:08 2010
@@ -1,4 +1,4 @@
-/* $NetBSD: pmap.c,v 1.260 2010/03/20 20:36:23 mrg Exp $ */
+/* $NetBSD: pmap.c,v 1.261 2010/03/21 22:38:08 mrg Exp $ */
/*
*
* Copyright (C) 1996-1999 Eduardo Horvath.
@@ -26,7 +26,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.260 2010/03/20 20:36:23 mrg Exp $");
+__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.261 2010/03/21 22:38:08 mrg Exp $");
#undef NO_VCACHE /* Don't forget the locked TLB in dostart */
#define HWREF
@@ -330,6 +330,7 @@
* Global pmap lock.
*/
static kmutex_t pmap_lock;
+static kmutex_t pmap_ctx_lock;
static bool lock_available = false;
/*
@@ -1293,7 +1294,8 @@
vm_first_phys = avail_start;
vm_num_phys = avail_end - avail_start;
- mutex_init(&pmap_lock, MUTEX_SPIN, IPL_VM);
+ mutex_init(&pmap_lock, MUTEX_DEFAULT, IPL_NONE);
+ mutex_init(&pmap_ctx_lock, MUTEX_SPIN, IPL_VM);
#if defined(USE_LOCKSAFE_PSEG_GETSET)
mutex_init(&pseg_lock, MUTEX_SPIN, IPL_VM);
#endif
@@ -1415,7 +1417,7 @@
return;
}
DPRINTF(PDB_DESTROY, ("pmap_destroy: freeing pmap %p\n", pm));
- mutex_enter(&pmap_lock);
+ mutex_enter(&pmap_ctx_lock);
#ifdef MULTIPROCESSOR
for (ci = cpus; ci != NULL; ci = ci->ci_next) {
if (CPUSET_HAS(cpus_active, ci->ci_index))
@@ -1424,7 +1426,7 @@
#else
ctx_free(pm, curcpu());
#endif
- mutex_exit(&pmap_lock);
+ mutex_exit(&pmap_ctx_lock);
/* we could be a little smarter and leave pages zeroed */
for (pg = TAILQ_FIRST(&pm->pm_obj.memq); pg != NULL; pg = nextpg) {
@@ -1922,7 +1924,7 @@
write_user_windows();
pm->pm_refs = 0;
- mutex_enter(&pmap_lock);
+ mutex_enter(&pmap_ctx_lock);
#ifdef MULTIPROCESSOR
CPUSET_CLEAR(pmap_cpus_active);
for (ci = cpus; ci != NULL; ci = ci->ci_next) {
@@ -1935,7 +1937,7 @@
#else
ctx_free(pm, curcpu());
#endif
- mutex_exit(&pmap_lock);
+ mutex_exit(&pmap_ctx_lock);
REMOVE_STAT(flushes);
#ifdef MULTIPROCESSOR
@@ -3071,7 +3073,7 @@
KASSERT(pm != pmap_kernel());
KASSERT(pm == curproc->p_vmspace->vm_map.pmap);
- mutex_enter(&pmap_lock);
+ mutex_enter(&pmap_ctx_lock);
ctx = curcpu()->ci_pmap_next_ctx++;
/*
@@ -3106,7 +3108,7 @@
curcpu()->ci_ctxbusy[ctx] = pm->pm_physaddr;
LIST_INSERT_HEAD(&curcpu()->ci_pmap_ctxlist, pm, pm_list[cpu_number()]);
pmap_ctx(pm) = ctx;
- mutex_exit(&pmap_lock);
+ mutex_exit(&pmap_ctx_lock);
DPRINTF(PDB_CTX_ALLOC, ("ctx_alloc: cpu%d allocated ctx %d\n",
cpu_number(), ctx));
return ctx;
@@ -3121,7 +3123,7 @@
int oldctx;
int cpunum;
- KASSERT(mutex_owned(&pmap_lock));
+ KASSERT(mutex_owned(&pmap_ctx_lock));
#ifdef MULTIPROCESSOR
cpunum = ci->ci_index;
