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Index: sys/arm64/arm64/pmap.c
===================================================================
--- sys/arm64/arm64/pmap.c
+++ sys/arm64/arm64/pmap.c
@@ -359,6 +359,8 @@
((u_long)(epoch) << 32)))
#define COOKIE_TO_ASID(cookie) ((int)(cookie))
#define COOKIE_TO_EPOCH(cookie) ((int)((u_long)(cookie) >> 32))
+#define COOKIE_TO_EPOCH_ATOMIC(cookie) ((int)(atomic_load_long( \
+ &(cookie)) >> 32))
static int superpages_enabled = 1;
SYSCTL_INT(_vm_pmap, OID_AUTO, superpages_enabled,
@@ -1175,6 +1177,32 @@
SYSCTL_ULONG(_vm_pmap_l2, OID_AUTO, promotions, CTLFLAG_RD,
&pmap_l2_promotions, 0, "2MB page promotions");
+static bool
+pmap_is_current_epoch(pmap_t pmap)
+{
+ struct asid_set *set;
+ int asid_epoch, epoch;
+
+ /* The kernel pmap is always current, and may not be locked */
+ if (pmap == kernel_pmap)
+ return (true);
+
+ PMAP_LOCK_ASSERT(pmap, MA_OWNED);
+ set = pmap->pm_asid_set;
+
+ /* Check if the epoch is marked as invalid */
+ epoch = COOKIE_TO_EPOCH_ATOMIC(pmap->pm_cookie);
+ if (epoch == INT_MAX)
+ return (false);
+
+ /* Assume current while pmap_reset_asid_set is being called */
+ asid_epoch = atomic_load_int(&set->asid_epoch);
+ if (asid_epoch == -1)
+ return (true);
+
+ return (epoch == asid_epoch);
+}
+
/*
* Invalidate a single TLB entry.
*/
@@ -1228,6 +1256,15 @@
PMAP_ASSERT_STAGE1(pmap);
+ /*
+ * Invalidating all entries can be expensive. Only do so if the pmap
+ * is on the current epoch. If not the pmap will have not been
+ * activated since the last time the entire tlb was invalidated so
+ * won't have been used.
+ */
+ if (!pmap_is_current_epoch(pmap))
+ return;
+
dsb(ishst);
if (pmap == kernel_pmap) {
__asm __volatile("tlbi vmalle1is");
@@ -6451,7 +6488,7 @@
epoch = set->asid_epoch + 1;
if (epoch == INT_MAX)
epoch = 0;
- set->asid_epoch = epoch;
+ atomic_store_int(&set->asid_epoch, -1);
dsb(ishst);
if (stage == PM_STAGE1) {
__asm __volatile("tlbi vmalle1is");
@@ -6481,8 +6518,10 @@
if (asid == -1)
continue;
bit_set(set->asid_set, asid);
- curpmap->pm_cookie = COOKIE_FROM(asid, epoch);
+ atomic_store_long(&curpmap->pm_cookie,
+ COOKIE_FROM(asid, epoch));
}
+ atomic_store_rel_int(&set->asid_epoch, epoch);
}
/*

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