Subject: Re: port-i386/37193 (x86 pmap concurrency strategy could use improvement)
To: None <gnats-bugs@NetBSD.org>
From: Manuel Bouyer <bouyer@antioche.eu.org>
List: port-xen
Date: 01/11/2008 23:13:19
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On Thu, Jan 10, 2008 at 08:01:52PM +0900, YAMAMOTO Takashi wrote:
> > Synopsis: x86 pmap concurrency strategy could use improvement
> >
> > Responsible-Changed-From-To: port-i386-maintainer->yamt
> > Responsible-Changed-By: yamt@netbsd.org
> > Responsible-Changed-When: Wed, 09 Jan 2008 11:45:50 +0000
> > Responsible-Changed-Why:
> > i'll take a look.
>
> here's a patch. can anyone test it on xen+amd64?
You can't map the ptp read/write on Xen. But with this issue fixed,
it works fine. I used the attached patch on HEAD after the bouyer-xeni386
merge.
--
Manuel Bouyer <bouyer@antioche.eu.org>
NetBSD: 26 ans d'experience feront toujours la difference
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Index: amd64/include/pmap.h
===================================================================
RCS file: /cvsroot/src/sys/arch/amd64/include/pmap.h,v
retrieving revision 1.18
diff -u -r1.18 pmap.h
--- amd64/include/pmap.h 3 Jan 2008 19:30:10 -0000 1.18
+++ amd64/include/pmap.h 11 Jan 2008 22:06:44 -0000
@@ -257,6 +257,7 @@
#define pmap_pa2pte(a) (a)
#define pmap_pte2pa(a) ((a) & PG_FRAME)
#define pmap_pte_set(p, n) do { *(p) = (n); } while (0)
+#define pmap_pte_cas(p, o, n) atomic_cas_64((p), (o), (n))
#define pmap_pte_testset(p, n) \
atomic_swap_ulong((volatile unsigned long *)p, n)
#define pmap_pte_setbits(p, b) \
@@ -285,6 +286,20 @@
}
static __inline pt_entry_t
+pmap_pte_cas(pt_entry_t *ptep, pt_entry_t o, pt_entry_t n)
+{
+ int s = splvm();
+ pt_entry_t opte = *ptep;
+
+ if (opte == o) {
+ xpq_queue_pte_update((pt_entry_t *)xpmap_ptetomach(ptep), n);
+ xpq_flush_queue();
+ }
+ splx(s);
+ return opte;
+}
+
+static __inline pt_entry_t
pmap_pte_testset(volatile pt_entry_t *pte, pt_entry_t npte)
{
int s = splvm();
Index: i386/include/pmap.h
===================================================================
RCS file: /cvsroot/src/sys/arch/i386/include/pmap.h,v
retrieving revision 1.98
diff -u -r1.98 pmap.h
--- i386/include/pmap.h 11 Jan 2008 20:00:15 -0000 1.98
+++ i386/include/pmap.h 11 Jan 2008 22:07:02 -0000
@@ -277,6 +277,7 @@
#define pmap_pa2pte(a) (a)
#define pmap_pte2pa(a) ((a) & PG_FRAME)
#define pmap_pte_set(p, n) do { *(p) = (n); } while (0)
+#define pmap_pte_cas(p, o, n) atomic_cas_32((p), (o), (n))
#define pmap_pte_testset(p, n) \
atomic_swap_ulong((volatile unsigned long *)p, n)
#define pmap_pte_setbits(p, b) \
@@ -305,6 +306,20 @@
}
static __inline pt_entry_t
+pmap_pte_cas(pt_entry_t *ptep, pt_entry_t o, pt_entry_t n)
+{
+ int s = splvm();
+ pt_entry_t opte = *ptep;
+
+ if (opte == o) {
+ xpq_queue_pte_update((pt_entry_t *)xpmap_ptetomach(ptep), n);
+ xpq_flush_queue();
+ }
+ splx(s);
+ return opte;
+}
+
+static __inline pt_entry_t
pmap_pte_testset(volatile pt_entry_t *pte, pt_entry_t npte)
{
int s = splvm();
Index: x86/x86/pmap.c
===================================================================
RCS file: /cvsroot/src/sys/arch/x86/x86/pmap.c,v
retrieving revision 1.24
diff -u -r1.24 pmap.c
--- x86/x86/pmap.c 11 Jan 2008 20:00:17 -0000 1.24
+++ x86/x86/pmap.c 11 Jan 2008 22:07:35 -0000
@@ -346,7 +346,6 @@
pd_entry_t *alternate_pdes[] = APDES_INITIALIZER;
static kmutex_t pmaps_lock;
-static krwlock_t pmap_main_lock;
static vaddr_t pmap_maxkvaddr;
@@ -557,6 +556,32 @@
* p m a p h e l p e r f u n c t i o n s
*/
+static inline void
+pmap_stats_update(struct pmap *pmap, int resid_diff, int wired_diff)
+{
+
+ if (pmap == pmap_kernel()) {
+ atomic_add_long(&pmap->pm_stats.resident_count, resid_diff);
+ atomic_add_long(&pmap->pm_stats.wired_count, wired_diff);
+ } else {
+ KASSERT(mutex_owned(&pmap->pm_lock));
+ pmap->pm_stats.resident_count += resid_diff;
+ pmap->pm_stats.wired_count += wired_diff;
+ }
+}
+
+static inline void
+pmap_stats_update_bypte(struct pmap *pmap, pt_entry_t npte, pt_entry_t opte)
+{
+ int resid_diff = ((npte & PG_V) ? 1 : 0) - ((opte & PG_V) ? 1 : 0);
+ int wired_diff = ((npte & PG_W) ? 1 : 0) - ((opte & PG_W) ? 1 : 0);
+
+ KASSERT((npte & (PG_V | PG_W)) != PG_W);
+ KASSERT((opte & (PG_V | PG_W)) != PG_W);
+
+ pmap_stats_update(pmap, resid_diff, wired_diff);
+}
+
/*
* pmap_is_curpmap: is this pmap the one currently loaded [in %cr3]?
* of course the kernel is always loaded
@@ -1299,7 +1324,6 @@
* again is never taken from interrupt context.
*/
- rw_init(&pmap_main_lock);
mutex_init(&pmaps_lock, MUTEX_DEFAULT, IPL_NONE);
LIST_INIT(&pmaps);
pmap_cpu_init_early(curcpu());
@@ -1505,6 +1529,8 @@
vaddr_t va,
struct vm_page *ptp) /* PTP in pmap that maps this VA */
{
+
+ KASSERT(mutex_owned(&pvh->pvh_lock));
pve->pv_pmap = pmap;
pve->pv_va = va;
pve->pv_ptp = ptp; /* NULL for kernel pmap */
@@ -1526,6 +1552,7 @@
{
struct pv_entry tmp, *pve;
+ KASSERT(mutex_owned(&pvh->pvh_lock));
tmp.pv_pmap = pmap;
tmp.pv_va = va;
pve = SPLAY_FIND(pvtree, &pvh->pvh_root, &tmp);
@@ -1569,7 +1596,7 @@
lidx = level - 1;
obj = &pmap->pm_obj[lidx];
- pmap->pm_stats.resident_count--;
+ pmap_stats_update(pmap, -1, 0);
if (lidx != 0)
mutex_enter(&obj->vmobjlock);
if (pmap->pm_ptphint[lidx] == ptp)
@@ -1699,7 +1726,7 @@
}
#endif /* XEN && __x86_64__ */
pmap_pte_flush();
- pmap->pm_stats.resident_count++;
+ pmap_stats_update(pmap, 1, 0);
/*
* If we're not in the top level, increase the
* wire count of the parent page.
@@ -2502,6 +2529,7 @@
pmap_map_ptes(pmap, &pmap2, &ptes, &pdes);
if (!pmap_pdes_valid(va, pdes, &pde)) {
+ pmap_unmap_ptes(pmap, pmap2);
return false;
}
@@ -2650,6 +2678,57 @@
#endif
}
+static pt_entry_t *
+pmap_map_ptp(struct vm_page *ptp)
+{
+ pt_entry_t *ptppte;
+ void *ptpva;
+ int id;
+
+ id = cpu_number();
+ ptppte = PTESLEW(ptp_pte, id);
+ ptpva = VASLEW(ptpp, id);
+ pmap_pte_set(ptppte, pmap_pa2pte(VM_PAGE_TO_PHYS(ptp)) |
+#ifdef XEN
+ PG_V | PG_M | PG_U | PG_k);
+#else
+ PG_V | PG_RW | PG_M | PG_U | PG_k);
+#endif
+ pmap_pte_flush();
+ pmap_update_pg((vaddr_t)ptpva);
+
+ return (pt_entry_t *)ptpva;
+}
+
+static void
+pmap_unmap_ptp(void)
+{
+#if defined(DIAGNOSTIC) || defined(XEN)
+ pt_entry_t *pte;
+
+ pte = PTESLEW(ptp_pte, cpu_number());
+ pmap_pte_set(pte, 0);
+ pmap_pte_flush();
+#endif
+}
+
+static pt_entry_t *
+pmap_map_pte(struct vm_page *ptp, vaddr_t va)
+{
+
+ if (ptp == NULL) {
+ return kvtopte(va);
+ }
+ return pmap_map_ptp(ptp) + pl1_pi(va);
+}
+
+static void
+pmap_unmap_pte(void)
+{
+
+ pmap_unmap_ptp();
+}
+
/*
* p m a p r e m o v e f u n c t i o n s
*
@@ -2701,9 +2780,7 @@
pmap_exec_account(pmap, startva, opte, 0);
KASSERT(pmap_valid_entry(opte));
- if (opte & PG_W)
- pmap->pm_stats.wired_count--;
- pmap->pm_stats.resident_count--;
+ pmap_stats_update_bypte(pmap, 0, opte);
xpte |= opte;
if (ptp) {
@@ -2784,9 +2861,7 @@
pmap_exec_account(pmap, va, opte, 0);
KASSERT(pmap_valid_entry(opte));
- if (opte & PG_W)
- pmap->pm_stats.wired_count--;
- pmap->pm_stats.resident_count--;
+ pmap_stats_update_bypte(pmap, 0, opte);
if (opte & PG_U)
pmap_tlb_shootdown(pmap, va, 0, opte);
@@ -2864,12 +2939,6 @@
struct vm_page *ptp, *empty_ptps = NULL;
struct pmap *pmap2;
- /*
- * we lock in the pmap => pv_head direction
- */
-
- rw_enter(&pmap_main_lock, RW_READER);
-
pmap_map_ptes(pmap, &pmap2, &ptes, &pdes); /* locks pmap */
/*
@@ -2971,7 +3040,6 @@
}
pmap_tlb_shootwait();
pmap_unmap_ptes(pmap, pmap2); /* unlock pmap */
- rw_exit(&pmap_main_lock);
/* Now we can free unused PVs and ptps */
if (pv_tofree)
@@ -2993,15 +3061,10 @@
pmap_page_remove(struct vm_page *pg)
{
struct pv_head *pvh;
- struct pv_entry *pve, *npve, *killlist = NULL;
- pt_entry_t *ptes, opte;
- pd_entry_t **pdes;
-#ifdef DIAGNOSTIC
- pd_entry_t pde;
-#endif
+ struct pv_entry *pve, *killlist = NULL;
struct vm_page *empty_ptps = NULL;
struct vm_page *ptp;
- struct pmap *pmap2;
+ pt_entry_t expect;
#ifdef DIAGNOSTIC
int bank, off;
@@ -3016,37 +3079,26 @@
return;
}
- /* set pv_head => pmap locking */
- rw_enter(&pmap_main_lock, RW_WRITER);
-
- for (pve = SPLAY_MIN(pvtree, &pvh->pvh_root); pve != NULL; pve = npve) {
- npve = SPLAY_NEXT(pvtree, &pvh->pvh_root, pve);
-
- /* locks pmap */
- pmap_map_ptes(pve->pv_pmap, &pmap2, &ptes, &pdes);
-
-#ifdef DIAGNOSTIC
- if (pve->pv_ptp && pmap_pdes_valid(pve->pv_va, pdes, &pde) &&
- pmap_pte2pa(pde) != VM_PAGE_TO_PHYS(pve->pv_ptp)) {
- printf("pmap_page_remove: pg=%p: va=%lx, pv_ptp=%p\n",
- pg, pve->pv_va, pve->pv_ptp);
- printf("pmap_page_remove: PTP's phys addr: "
- "actual=%lx, recorded=%lx\n",
- (unsigned long)pmap_pte2pa(pde),
- (unsigned long)VM_PAGE_TO_PHYS(pve->pv_ptp));
- panic("pmap_page_remove: mapped managed page has "
- "invalid pv_ptp field");
- }
-#endif
+ expect = pmap_pa2pte(VM_PAGE_TO_PHYS(pg)) | PG_V;
+retry:
+ mutex_spin_enter(&pvh->pvh_lock);
+ while ((pve = SPLAY_MIN(pvtree, &pvh->pvh_root)) != NULL) {
+ struct pmap *pmap = pve->pv_pmap;
+ pt_entry_t *ptep;
+ pt_entry_t opte;
/* atomically save the old PTE and zap! it */
- opte = pmap_pte_testset(&ptes[pl1_i(pve->pv_va)], 0);
- KASSERT(pmap_valid_entry(opte));
- KDASSERT(pmap_pte2pa(opte) == VM_PAGE_TO_PHYS(pg));
-
- if (opte & PG_W)
- pve->pv_pmap->pm_stats.wired_count--;
- pve->pv_pmap->pm_stats.resident_count--;
+ ptep = pmap_map_pte(pve->pv_ptp, pve->pv_va);
+ do {
+ opte = *ptep;
+ if ((opte & (PG_FRAME | PG_V)) != expect) {
+ pmap_unmap_pte();
+ mutex_spin_exit(&pvh->pvh_lock);
+ x86_pause();
+ goto retry;
+ }
+ } while (pmap_pte_cas(ptep, opte, 0) != opte);
+ pmap_unmap_pte();
/* Shootdown only if referenced */
if (opte & PG_U)
@@ -3055,21 +3107,37 @@
/* sync R/M bits */
pg->mdpage.mp_attrs |= (opte & (PG_U|PG_M));
+ if (pve->pv_ptp) {
+ pmap_reference(pmap);
+ }
+ SPLAY_REMOVE(pvtree, &pvh->pvh_root, pve); /* remove it */
+ mutex_spin_exit(&pvh->pvh_lock);
+
/* update the PTP reference count. free if last reference. */
if (pve->pv_ptp) {
+ struct pmap *pmap2;
+ pt_entry_t *ptes;
+ pd_entry_t **pdes;
+
+ KASSERT(pmap != pmap_kernel());
+ pmap_map_ptes(pmap, &pmap2, &ptes, &pdes);
+ pmap_stats_update_bypte(pmap, 0, opte);
pve->pv_ptp->wire_count--;
if (pve->pv_ptp->wire_count <= 1) {
pmap_free_ptp(pve->pv_pmap, pve->pv_ptp,
pve->pv_va, ptes, pdes, &empty_ptps);
}
+ pmap_unmap_ptes(pmap, pmap2);
+ pmap_destroy(pmap);
+ } else {
+ pmap_stats_update_bypte(pmap, 0, opte);
}
-
- pmap_unmap_ptes(pve->pv_pmap, pmap2); /* unlocks pmap */
- SPLAY_REMOVE(pvtree, &pvh->pvh_root, pve); /* remove it */
+
SPLAY_RIGHT(pve, pv_node) = killlist; /* mark it for death */
killlist = pve;
+ mutex_spin_enter(&pvh->pvh_lock);
}
- rw_exit(&pmap_main_lock);
+ mutex_spin_exit(&pvh->pvh_lock);
crit_enter();
pmap_tlb_shootwait();
@@ -3103,8 +3171,8 @@
int *myattrs;
struct pv_head *pvh;
struct pv_entry *pve;
- struct pmap *pmap2;
pt_entry_t pte;
+ pt_entry_t expect;
#if DIAGNOSTIC
int bank, off;
@@ -3131,26 +3199,28 @@
}
/* nope, gonna have to do it the hard way */
- rw_enter(&pmap_main_lock, RW_WRITER);
+ expect = pmap_pa2pte(VM_PAGE_TO_PHYS(pg)) | PG_V;
+ mutex_spin_enter(&pvh->pvh_lock);
for (pve = SPLAY_MIN(pvtree, &pvh->pvh_root);
pve != NULL && (*myattrs & testbits) == 0;
pve = SPLAY_NEXT(pvtree, &pvh->pvh_root, pve)) {
- pt_entry_t *ptes;
- pd_entry_t **pdes;
+ pt_entry_t *ptep;
- pmap_map_ptes(pve->pv_pmap, &pmap2, &ptes, &pdes);
- pte = ptes[pl1_i(pve->pv_va)];
- pmap_unmap_ptes(pve->pv_pmap, pmap2);
- *myattrs |= pte;
+ ptep = pmap_map_pte(pve->pv_ptp, pve->pv_va);
+ pte = *ptep;
+ pmap_unmap_pte();
+ if ((pte & (PG_FRAME | PG_V)) == expect) {
+ *myattrs |= pte;
+ }
}
+ mutex_spin_exit(&pvh->pvh_lock);
/*
* note that we will exit the for loop with a non-null pve if
* we have found the bits we are testing for.
*/
- rw_exit(&pmap_main_lock);
return((*myattrs & testbits) != 0);
}
@@ -3168,10 +3238,8 @@
uint32_t result;
struct pv_head *pvh;
struct pv_entry *pve;
- pt_entry_t *ptes, opte;
int *myattrs;
- struct pmap *pmap2;
-
+ pt_entry_t expect;
#ifdef DIAGNOSTIC
int bank, off;
@@ -3180,33 +3248,26 @@
panic("pmap_change_attrs: unmanaged page?");
#endif
mdpg = &pg->mdpage;
-
- rw_enter(&pmap_main_lock, RW_WRITER);
pvh = &mdpg->mp_pvhead;
-
myattrs = &mdpg->mp_attrs;
+ expect = pmap_pa2pte(VM_PAGE_TO_PHYS(pg)) | PG_V;
+
+ mutex_spin_enter(&pvh->pvh_lock);
result = *myattrs & clearbits;
*myattrs &= ~clearbits;
-
SPLAY_FOREACH(pve, pvtree, &pvh->pvh_root) {
pt_entry_t *ptep;
- pd_entry_t **pdes;
+ pt_entry_t opte;
- /* locks pmap */
- pmap_map_ptes(pve->pv_pmap, &pmap2, &ptes, &pdes);
-#ifdef DIAGNOSTIC
- if (!pmap_pdes_valid(pve->pv_va, pdes, NULL))
- panic("pmap_change_attrs: mapping without PTP "
- "detected");
-#endif
- ptep = &ptes[pl1_i(pve->pv_va)];
+ ptep = pmap_map_pte(pve->pv_ptp, pve->pv_va);
+retry:
opte = *ptep;
- KASSERT(pmap_valid_entry(opte));
- KDASSERT(pmap_pte2pa(opte) == VM_PAGE_TO_PHYS(pg));
+ if ((opte & (PG_FRAME | PG_V)) != expect) {
+ goto no_tlb_shootdown;
+ }
if (opte & clearbits) {
/* We need to do something */
if (clearbits == PG_RW) {
- result |= PG_RW;
/*
* On write protect we might not need to flush
@@ -3214,8 +3275,12 @@
*/
/* First zap the RW bit! */
- pmap_pte_clearbits(ptep, PG_RW);
- opte = *ptep;
+ if (pmap_pte_cas(ptep, opte, opte & ~PG_RW)
+ != opte) {
+ goto retry;
+ }
+ opte &= ~PG_RW;
+ result |= PG_RW;
/*
* Then test if it is not cached as RW the TLB
@@ -3230,7 +3295,10 @@
*/
/* zap! */
- opte = pmap_pte_testset(ptep, (opte & ~(PG_U | PG_M)));
+ if (pmap_pte_cas(ptep, opte, opte & ~(PG_U | PG_M))
+ != opte) {
+ goto retry;
+ }
result |= (opte & clearbits);
*myattrs |= (opte & ~(clearbits));
@@ -3238,10 +3306,9 @@
pmap_tlb_shootdown(pve->pv_pmap, pve->pv_va, 0, opte);
}
no_tlb_shootdown:
- pmap_unmap_ptes(pve->pv_pmap, pmap2); /* unlocks pmap */
+ pmap_unmap_pte();
}
-
- rw_exit(&pmap_main_lock);
+ mutex_spin_exit(&pvh->pvh_lock);
crit_enter();
pmap_tlb_shootwait();
@@ -3366,14 +3433,18 @@
pmap_map_ptes(pmap, &pmap2, &ptes, &pdes); /* locks pmap */
if (pmap_pdes_valid(va, pdes, NULL)) {
+ pt_entry_t *ptep = &ptes[pl1_i(va)];
+ pt_entry_t opte = *ptep;
#ifdef DIAGNOSTIC
- if (!pmap_valid_entry(ptes[pl1_i(va)]))
+ if (!pmap_valid_entry(opte))
panic("pmap_unwire: invalid (unmapped) va 0x%lx", va);
#endif
- if ((ptes[pl1_i(va)] & PG_W) != 0) {
- pmap_pte_clearbits(&ptes[pl1_i(va)], PG_W);
- pmap->pm_stats.wired_count--;
+ if ((opte & PG_W) != 0) {
+ pt_entry_t npte = opte & ~PG_W;
+
+ opte = pmap_pte_testset(ptep, npte);
+ pmap_stats_update_bypte(pmap, npte, opte);
}
#ifdef DIAGNOSTIC
else {
@@ -3488,9 +3559,6 @@
/* get a pve. */
freepve = pool_cache_get(&pmap_pv_cache, PR_NOWAIT);
- /* get lock */
- rw_enter(&pmap_main_lock, RW_READER);
-
pmap_map_ptes(pmap, &pmap2, &ptes, &pdes); /* locks pmap */
if (pmap == pmap_kernel()) {
ptp = NULL;
@@ -3540,8 +3608,7 @@
* change since we are replacing/changing a valid mapping.
* wired count might change...
*/
- pmap->pm_stats.wired_count +=
- ((npte & PG_W) ? 1 : 0 - (opte & PG_W) ? 1 : 0);
+ pmap_stats_update_bypte(pmap, npte, opte);
/*
* if this is on the PVLIST, sync R/M bit
@@ -3608,8 +3675,7 @@
* change since we are replacing/changing a valid mapping.
* wired count might change...
*/
- pmap->pm_stats.wired_count +=
- ((npte & PG_W) ? 1 : 0 - (opte & PG_W) ? 1 : 0);
+ pmap_stats_update_bypte(pmap, npte, opte);
if (opte & PG_PVLIST) {
pg = PHYS_TO_VM_PAGE(pmap_pte2pa(opte));
@@ -3633,9 +3699,8 @@
(pt_entry_t *)vtomach((vaddr_t)ptep),
npte, domid);
if (error) {
- pmap->pm_stats.wired_count -=
- ((npte & PG_W) ? 1 : 0 -
- (opte & PG_W) ? 1 : 0);
+ pmap_stats_update_bypte(pmap, opte,
+ npte);
splx(s);
mutex_spin_exit(&old_pvh->pvh_lock);
goto out;
@@ -3659,9 +3724,7 @@
goto shootdown_test;
}
} else { /* opte not valid */
- pmap->pm_stats.resident_count++;
- if (wired)
- pmap->pm_stats.wired_count++;
+ pmap_stats_update(pmap, 1, (wired) ? 1 : 0);
if (ptp)
ptp->wire_count++;
}
@@ -3676,13 +3739,11 @@
splx(s);
if (error) {
if (pmap_valid_entry(opte)) {
- pmap->pm_stats.wired_count -=
- ((npte & PG_W) ? 1 : 0 -
- (opte & PG_W) ? 1 : 0);
+ pmap_stats_update(pmap, 0,
+ -((npte & PG_W) ? 1 : 0 -
+ (opte & PG_W) ? 1 : 0));
} else { /* opte not valid */
- pmap->pm_stats.resident_count--;
- if (wired)
- pmap->pm_stats.wired_count--;
+ pmap_stats_update(pmap, -1, wired ? -1 : 0);
if (ptp)
ptp->wire_count--;
}
@@ -3710,7 +3771,6 @@
out:
pmap_unmap_ptes(pmap, pmap2);
- rw_exit(&pmap_main_lock);
if (freepve != NULL) {
/* put back the pv, we don't need it. */
@@ -3777,7 +3837,7 @@
ptp->wire_count = 1;
*paddrp = VM_PAGE_TO_PHYS(ptp);
}
- kpm->pm_stats.resident_count++;
+ pmap_stats_update(kpm, 1, 0);
return true;
}
@@ -3958,7 +4018,6 @@
* we lock in the pmap => pv_head direction
*/
- rw_enter(&pmap_main_lock, RW_READER);
pmap_map_ptes(pmap, &pmap2, &ptes, &pdes); /* locks pmap */
/*
@@ -3986,7 +4045,6 @@
}
}
pmap_unmap_ptes(pmap, pmap2);
- rw_exit(&pmap_main_lock);
}
#endif
--k1lZvvs/B4yU6o8G--