svn commit: r303585 - head/sys/arm64/arm64

[Andrew Turner]

Author: andrew
Date: Sun Jul 31 12:59:10 2016
New Revision: 303585
URL: https://svnweb.freebsd.org/changeset/base/303585

Log:
  Relax the barriers around a TLB invalidation to only wait on
  inner-shareable memory accesses. There is no need for full system barriers.
  
  Obtained from:	ABT Systems Ltd
  MFC after:	1 month
  Sponsored by:	The FreeBSD Foundation

Modified:
  head/sys/arm64/arm64/pmap.c

Modified: head/sys/arm64/arm64/pmap.c
==============================================================================
--- head/sys/arm64/arm64/pmap.c	Sun Jul 31 12:11:55 2016	(r303584)
+++ head/sys/arm64/arm64/pmap.c	Sun Jul 31 12:59:10 2016	(r303585)
@@ -865,9 +865,9 @@ pmap_invalidate_page(pmap_t pmap, vm_off
 
 	sched_pin();
 	__asm __volatile(
-	    "dsb  sy		\n"
+	    "dsb  ishst		\n"
 	    "tlbi vaae1is, %0	\n"
-	    "dsb  sy		\n"
+	    "dsb  ish		\n"
 	    "isb		\n"
 	    : : "r"(va >> PAGE_SHIFT));
 	sched_unpin();
@@ -879,13 +879,13 @@ pmap_invalidate_range(pmap_t pmap, vm_of
 	vm_offset_t addr;
 
 	sched_pin();
-	__asm __volatile("dsb	sy");
+	dsb(ishst);
 	for (addr = sva; addr < eva; addr += PAGE_SIZE) {
 		__asm __volatile(
 		    "tlbi vaae1is, %0" : : "r"(addr >> PAGE_SHIFT));
 	}
 	__asm __volatile(
-	    "dsb  sy	\n"
+	    "dsb  ish	\n"
 	    "isb	\n");
 	sched_unpin();
 }
@@ -896,9 +896,9 @@ pmap_invalidate_all(pmap_t pmap)
 
 	sched_pin();
 	__asm __volatile(
-	    "dsb  sy		\n"
+	    "dsb  ishst		\n"
 	    "tlbi vmalle1is	\n"
-	    "dsb  sy		\n"
+	    "dsb  ish		\n"
 	    "isb		\n");
 	sched_unpin();
 }