From: kettenis <kettenis@openbsd.org>
Date: Sat, 15 Apr 2017 11:15:02 +0000 (+0000)
Subject: The tlb flushes in pmap_set_{l1,l2,l3} use ranges that don't fully make sense.
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=84b05fcf8dd3680e0dab6b70d8946bd1cced30f3;p=openbsd

The tlb flushes in pmap_set_{l1,l2,l3} use ranges that don't fully make sense.
But those tlb flushes shouldn't be necessary anyway, so simply remove them.
Simplify the tlb flushing code now that we no longer flush ranges, and
revive the branch that doesn't flush a specific ASID for the kernel pmap
since its mappings are global.

ok patrick@, visa@
---

diff --git a/sys/arch/arm64/arm64/pmap.c b/sys/arch/arm64/arm64/pmap.c
index 73413f0fb64..0e9c8dda9cb 100644
--- a/sys/arch/arm64/arm64/pmap.c
+++ b/sys/arch/arm64/arm64/pmap.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: pmap.c,v 1.32 2017/04/13 20:48:29 kettenis Exp $ */
+/* $OpenBSD: pmap.c,v 1.33 2017/04/15 11:15:02 kettenis Exp $ */
 /*
  * Copyright (c) 2008-2009,2014-2016 Dale Rahn <drahn@dalerahn.com>
  *
@@ -35,7 +35,6 @@
 #include <ddb/db_output.h>
 
 void pmap_setttb(struct proc *p);
-void arm64_tlbi_asid(vaddr_t va, int asid);
 void pmap_free_asid(pmap_t pm);
 
 /*
@@ -67,35 +66,14 @@ pmap_pa_is_mem(uint64_t pa)
 
 static inline void
 ttlb_flush(pmap_t pm, vaddr_t va)
-{
-	arm64_tlbi_asid(va, pm->pm_asid);
-}
-
-static inline void
-ttlb_flush_range(pmap_t pm, vaddr_t va, vsize_t size)
-{
-	vaddr_t eva = va + size;
-
-	/* if size is over 512 pages, just flush the entire cache !?!?! */
-	if (size >= (512 * PAGE_SIZE)) {
-		cpu_tlb_flush();
-		return;
-	}
-
-	for ( ; va < eva; va += PAGE_SIZE)
-		arm64_tlbi_asid(va, pm->pm_asid);
-}
-
-void
-arm64_tlbi_asid(vaddr_t va, int asid)
 {
 	vaddr_t resva;
 
 	resva = ((va >> PAGE_SHIFT) & ((1ULL << 44) - 1));
-	if (asid == -1) {
+	if (pm == pmap_kernel()) {
 		cpu_tlb_flush_all_asid(resva);
 	} else {
-		resva |= (unsigned long long)asid << 48;
+		resva |= (uint64_t)pm->pm_asid << 48;
 		cpu_tlb_flush_asid(resva);
 	}
 }
@@ -1267,8 +1245,6 @@ pmap_set_l1(struct pmap *pm, uint64_t va, struct pmapvp1 *l1_va, paddr_t l1_pa)
 	idx0 = VP_IDX0(va);
 	pm->pm_vp.l0->vp[idx0] = l1_va;
 	pm->pm_vp.l0->l0[idx0] = pg_entry;
-
-	ttlb_flush_range(pm, va & ~PAGE_MASK, 1<<VP_IDX1_POS);
 }
 
 void
@@ -1299,8 +1275,6 @@ pmap_set_l2(struct pmap *pm, uint64_t va, struct pmapvp2 *l2_va, paddr_t l2_pa)
 		vp1 = pm->pm_vp.l1;
 	vp1->vp[idx1] = l2_va;
 	vp1->l1[idx1] = pg_entry;
-
-	ttlb_flush_range(pm, va & ~PAGE_MASK, 1<<VP_IDX2_POS);
 }
 
 void
@@ -1334,8 +1308,6 @@ pmap_set_l3(struct pmap *pm, uint64_t va, struct pmapvp3 *l3_va, paddr_t l3_pa)
 	vp2 = vp1->vp[idx1];
 	vp2->vp[idx2] = l3_va;
 	vp2->l2[idx2] = pg_entry;
-
-	ttlb_flush_range(pm, va & ~PAGE_MASK, 1<<VP_IDX3_POS);
 }
 
 /*
@@ -1578,7 +1550,7 @@ pmap_pte_remove(struct pte_desc *pted, int remove_pted)
 	if (remove_pted)
 		vp3->vp[VP_IDX3(pted->pted_va)] = NULL;
 
-	arm64_tlbi_asid(pted->pted_va, pm->pm_asid);
+	ttlb_flush(pm, pted->pted_va);
 }
 
 /*