Module Name: src
Committed By: rmind
Date: Sun Apr 25 15:47:52 UTC 2010
Modified Files:
src/sys/arch/x86/include [rmind-uvmplock]: pmap_pv.h
src/sys/arch/x86/x86 [rmind-uvmplock]: pmap.c
Log Message:
Drop per-"MD page" (i.e. struct pmap_page) locking i.e. pp_lock/pp_unlock
and rely on locking provided by upper layer, UVM. Sprinkle asserts.
To generate a diff of this commit:
cvs rdiff -u -r1.2 -r1.2.36.1 src/sys/arch/x86/include/pmap_pv.h
cvs rdiff -u -r1.105.2.1 -r1.105.2.2 src/sys/arch/x86/x86/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/x86/include/pmap_pv.h
diff -u src/sys/arch/x86/include/pmap_pv.h:1.2 src/sys/arch/x86/include/pmap_pv.h:1.2.36.1
--- src/sys/arch/x86/include/pmap_pv.h:1.2 Mon Jan 28 11:06:42 2008
+++ src/sys/arch/x86/include/pmap_pv.h Sun Apr 25 15:47:52 2010
@@ -1,4 +1,4 @@
-/* $NetBSD: pmap_pv.h,v 1.2 2008/01/28 11:06:42 yamt Exp $ */
+/* $NetBSD: pmap_pv.h,v 1.2.36.1 2010/04/25 15:47:52 rmind Exp $ */
/*-
* Copyright (c)2008 YAMAMOTO Takashi,
@@ -65,7 +65,6 @@
*/
struct pmap_page {
- kmutex_t pp_lock;
union {
/* PP_EMBEDDED */
struct pv_pte u_pte;
@@ -88,7 +87,6 @@
/* pp_flags */
#define PP_EMBEDDED 1
-#define PMAP_PAGE_INIT(pp) \
- mutex_init(&(pp)->pp_lock, MUTEX_NODEBUG, IPL_VM)
+#define PMAP_PAGE_INIT(pp) /* none */
#endif /* !_X86_PMAP_PV_H_ */
Index: src/sys/arch/x86/x86/pmap.c
diff -u src/sys/arch/x86/x86/pmap.c:1.105.2.1 src/sys/arch/x86/x86/pmap.c:1.105.2.2
--- src/sys/arch/x86/x86/pmap.c:1.105.2.1 Tue Mar 16 15:38:04 2010
+++ src/sys/arch/x86/x86/pmap.c Sun Apr 25 15:47:52 2010
@@ -1,4 +1,4 @@
-/* $NetBSD: pmap.c,v 1.105.2.1 2010/03/16 15:38:04 rmind Exp $ */
+/* $NetBSD: pmap.c,v 1.105.2.2 2010/04/25 15:47:52 rmind Exp $ */
/*
* Copyright (c) 2007 Manuel Bouyer.
@@ -149,7 +149,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.105.2.1 2010/03/16 15:38:04 rmind Exp $");
+__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.105.2.2 2010/04/25 15:47:52 rmind Exp $");
#include "opt_user_ldt.h"
#include "opt_lockdebug.h"
@@ -417,10 +417,6 @@
#define VM_PAGE_TO_PP(pg) (&(pg)->mdpage.mp_pp)
-#define pp_lock(pp) mutex_spin_enter(&(pp)->pp_lock)
-#define pp_unlock(pp) mutex_spin_exit(&(pp)->pp_lock)
-#define pp_locked(pp) mutex_owned(&(pp)->pp_lock)
-
#define PV_HASH_SIZE 32768
#define PV_HASH_LOCK_CNT 32
@@ -674,7 +670,6 @@
pv_pte_first(struct pmap_page *pp)
{
- KASSERT(pp_locked(pp));
if ((pp->pp_flags & PP_EMBEDDED) != 0) {
return &pp->pp_pte;
}
@@ -686,7 +681,6 @@
{
KASSERT(pvpte != NULL);
- KASSERT(pp_locked(pp));
if (pvpte == &pp->pp_pte) {
KASSERT((pp->pp_flags & PP_EMBEDDED) != 0);
return NULL;
@@ -1739,8 +1733,6 @@
kmutex_t *lock;
u_int hash;
- KASSERT(pp_locked(pp));
-
hash = pvhash_hash(pve->pve_pte.pte_ptp, pve->pve_pte.pte_va);
lock = pvhash_lock(hash);
hh = pvhash_head(hash);
@@ -1754,7 +1746,6 @@
/*
* pmap_enter_pv: enter a mapping onto a pv_head lst
*
- * => caller should have the pp_lock locked
* => caller should adjust ptp's wire_count before calling
*/
@@ -1769,7 +1760,6 @@
KASSERT(ptp == NULL || ptp->wire_count >= 2);
KASSERT(ptp == NULL || ptp->uobject != NULL);
KASSERT(ptp == NULL || ptp_va2o(va, 1) == ptp->offset);
- KASSERT(pp_locked(pp));
if ((pp->pp_flags & PP_EMBEDDED) == 0) {
if (LIST_EMPTY(&pp->pp_head.pvh_list)) {
@@ -1801,7 +1791,6 @@
/*
* pmap_remove_pv: try to remove a mapping from a pv_list
*
- * => caller should hold pp_lock [so that attrs can be adjusted]
* => caller should adjust ptp's wire_count and free PTP if needed
* => we return the removed pve
*/
@@ -1816,7 +1805,6 @@
KASSERT(ptp == NULL || ptp->uobject != NULL);
KASSERT(ptp == NULL || ptp_va2o(va, 1) == ptp->offset);
- KASSERT(pp_locked(pp));
if ((pp->pp_flags & PP_EMBEDDED) != 0) {
KASSERT(pp->pp_pte.pte_ptp == ptp);
@@ -3242,7 +3230,6 @@
/*
* pmap_remove_ptes: remove PTEs from a PTP
*
- * => must have proper locking on pmap_master_lock
* => caller must hold pmap's lock
* => PTP must be mapped into KVA
* => PTP should be null if pmap == pmap_kernel()
@@ -3309,20 +3296,17 @@
}
pg = PHYS_TO_VM_PAGE(pmap_pte2pa(opte));
-#ifdef DIAGNOSTIC
- if (pg == NULL)
- panic("pmap_remove_ptes: unmanaged page marked "
- "PG_PVLIST, va = %#" PRIxVADDR ", "
- "pa = %#" PRIxPADDR,
- startva, (paddr_t)pmap_pte2pa(opte));
-#endif
+
+ KASSERTMSG(pg != NULL, ("pmap_remove_ptes: unmanaged page "
+ "marked PG_PVLIST, va = %#" PRIxVADDR ", pa = %#" PRIxPADDR,
+ startva, (paddr_t)pmap_pte2pa(opte)));
+
+ KASSERT(uvm_page_locked_p(pg));
/* sync R/M bits */
pp = VM_PAGE_TO_PP(pg);
- pp_lock(pp);
pp->pp_attrs |= opte;
pve = pmap_remove_pv(pp, ptp, startva);
- pp_unlock(pp);
if (pve != NULL) {
pve->pve_next = *pv_tofree;
@@ -3339,7 +3323,6 @@
/*
* pmap_remove_pte: remove a single PTE from a PTP
*
- * => must have proper locking on pmap_master_lock
* => caller must hold pmap's lock
* => PTP must be mapped into KVA
* => PTP should be null if pmap == pmap_kernel()
@@ -3395,19 +3378,17 @@
}
pg = PHYS_TO_VM_PAGE(pmap_pte2pa(opte));
-#ifdef DIAGNOSTIC
- if (pg == NULL)
- panic("pmap_remove_pte: unmanaged page marked "
- "PG_PVLIST, va = %#" PRIxVADDR ", pa = %#" PRIxPADDR,
- va, (paddr_t)pmap_pte2pa(opte));
-#endif
+
+ KASSERTMSG(pg != NULL, ("pmap_remove_pte: unmanaged page marked "
+ "PG_PVLIST, va = %#" PRIxVADDR ", pa = %#" PRIxPADDR,
+ va, (paddr_t)pmap_pte2pa(opte)));
+
+ KASSERT(uvm_page_locked_p(pg));
/* sync R/M bits */
pp = VM_PAGE_TO_PP(pg);
- pp_lock(pp);
pp->pp_attrs |= opte;
pve = pmap_remove_pv(pp, ptp, va);
- pp_unlock(pp);
if (pve) {
pve->pve_next = *pv_tofree;
@@ -3545,7 +3526,7 @@
/*
* pmap_sync_pv: clear pte bits and return the old value of the pte.
*
- * => called with pp_lock held. (thus preemption disabled)
+ * => Caller should disable kernel preemption.
* => issues tlb shootdowns if necessary.
*/
@@ -3656,13 +3637,14 @@
lwp_t *l;
int count;
+ KASSERT(uvm_page_locked_p(pg));
+
l = curlwp;
pp = VM_PAGE_TO_PP(pg);
expect = pmap_pa2pte(VM_PAGE_TO_PHYS(pg)) | PG_V;
count = SPINLOCK_BACKOFF_MIN;
kpreempt_disable();
startover:
- pp_lock(pp);
while ((pvpte = pv_pte_first(pp)) != NULL) {
struct pmap *pmap;
struct pv_entry *pve;
@@ -3684,7 +3666,6 @@
error = pmap_sync_pv(pvpte, expect, ~0, &opte);
if (error == EAGAIN) {
int hold_count;
- pp_unlock(pp);
KERNEL_UNLOCK_ALL(curlwp, &hold_count);
if (ptp != NULL) {
pmap_destroy(pmap);
@@ -3697,7 +3678,6 @@
pp->pp_attrs |= opte;
va = pvpte->pte_va;
pve = pmap_remove_pv(pp, ptp, va);
- pp_unlock(pp);
/* update the PTP reference count. free if last reference. */
if (ptp != NULL) {
@@ -3725,9 +3705,7 @@
pve->pve_next = killlist; /* mark it for death */
killlist = pve;
}
- pp_lock(pp);
}
- pp_unlock(pp);
kpreempt_enable();
/* Now free unused pvs. */
@@ -3753,12 +3731,14 @@
pt_entry_t expect;
u_int result;
+ KASSERT(uvm_page_locked_p(pg));
+
pp = VM_PAGE_TO_PP(pg);
if ((pp->pp_attrs & testbits) != 0) {
return true;
}
expect = pmap_pa2pte(VM_PAGE_TO_PHYS(pg)) | PG_V;
- pp_lock(pp);
+ kpreempt_disable();
for (pvpte = pv_pte_first(pp); pvpte; pvpte = pv_pte_next(pp, pvpte)) {
pt_entry_t opte;
int error;
@@ -3772,7 +3752,7 @@
}
}
result = pp->pp_attrs & testbits;
- pp_unlock(pp);
+ kpreempt_enable();
/*
* note that we will exit the for loop with a non-null pve if
@@ -3797,12 +3777,13 @@
pt_entry_t expect;
int count;
+ KASSERT(uvm_page_locked_p(pg));
+
pp = VM_PAGE_TO_PP(pg);
expect = pmap_pa2pte(VM_PAGE_TO_PHYS(pg)) | PG_V;
count = SPINLOCK_BACKOFF_MIN;
kpreempt_disable();
startover:
- pp_lock(pp);
for (pvpte = pv_pte_first(pp); pvpte; pvpte = pv_pte_next(pp, pvpte)) {
pt_entry_t opte;
int error;
@@ -3810,7 +3791,6 @@
error = pmap_sync_pv(pvpte, expect, clearbits, &opte);
if (error == EAGAIN) {
int hold_count;
- pp_unlock(pp);
KERNEL_UNLOCK_ALL(curlwp, &hold_count);
SPINLOCK_BACKOFF(count);
KERNEL_LOCK(hold_count, curlwp);
@@ -3820,7 +3800,6 @@
}
result = pp->pp_attrs & clearbits;
pp->pp_attrs &= ~clearbits;
- pp_unlock(pp);
kpreempt_enable();
return result != 0;
@@ -4163,19 +4142,16 @@
if ((~opte & (PG_V | PG_PVLIST)) == 0) {
pg = PHYS_TO_VM_PAGE(pmap_pte2pa(opte));
-#ifdef DIAGNOSTIC
- if (pg == NULL)
- panic("pmap_enter: PG_PVLIST mapping with "
- "unmanaged page "
- "pa = 0x%" PRIx64 " (0x%" PRIx64 ")",
- (int64_t)pa, (int64_t)atop(pa));
-#endif
- old_pp = VM_PAGE_TO_PP(pg);
- pp_lock(old_pp);
+ KASSERTMSG(pg != NULL, ("pmap_enter: PG_PVLIST mapping with "
+ "unmanaged page pa = 0x%" PRIx64 " (0x%" PRIx64 ")",
+ (int64_t)pa, (int64_t)atop(pa)));
+
+ KASSERT(uvm_page_locked_p(pg));
+
+ old_pp = VM_PAGE_TO_PP(pg);
old_pve = pmap_remove_pv(old_pp, ptp, va);
old_pp->pp_attrs |= opte;
- pp_unlock(old_pp);
}
/*
@@ -4183,9 +4159,7 @@
*/
if (new_pp) {
- pp_lock(new_pp);
new_pve = pmap_enter_pv(new_pp, new_pve, &new_pve2, ptp, va);
- pp_unlock(new_pp);
}
same_pa:
