svn commit: r349768 - head/sys/arm64/arm64
Alan Cox
alc at FreeBSD.org
Fri Jul 5 20:01:07 UTC 2019
Author: alc
Date: Fri Jul 5 20:01:06 2019
New Revision: 349768
URL: https://svnweb.freebsd.org/changeset/base/349768
Log:
Restructure cache_handle_range to avoid repeated barriers. Specifically,
restructure cache_handle_range so that all of the data cache operations are
performed before any instruction cache operations. Then, we only need one
barrier between the data and instruction cache operations and one barrier
after the instruction cache operations.
On an Amazon EC2 a1.2xlarge instance, this simple change reduces the time
for a "make -j8 buildworld" by 9%.
Reviewed by: andrew
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D20848
Modified:
head/sys/arm64/arm64/cpufunc_asm.S
Modified: head/sys/arm64/arm64/cpufunc_asm.S
==============================================================================
--- head/sys/arm64/arm64/cpufunc_asm.S Fri Jul 5 16:49:34 2019 (r349767)
+++ head/sys/arm64/arm64/cpufunc_asm.S Fri Jul 5 20:01:06 2019 (r349768)
@@ -51,7 +51,7 @@ __FBSDID("$FreeBSD$");
/*
* Macro to handle the cache. This takes the start address in x0, length
- * in x1. It will corrupt x0, x1, x2, and x3.
+ * in x1. It will corrupt x0, x1, x2, x3, and x4.
*/
.macro cache_handle_range dcop = 0, ic = 0, icop = 0
.if \ic == 0
@@ -64,17 +64,23 @@ __FBSDID("$FreeBSD$");
and x2, x0, x4 /* Get the low bits of the address */
add x1, x1, x2 /* Add these to the size */
bic x0, x0, x4 /* Clear the low bit of the address */
-1:
- dc \dcop, x0
- dsb ish
.if \ic != 0
- ic \icop, x0
- dsb ish
+ mov x2, x0 /* Save the address */
+ mov x4, x1 /* Save the size */
.endif
+1:
+ dc \dcop, x0
add x0, x0, x3 /* Move to the next line */
subs x1, x1, x3 /* Reduce the size */
b.hi 1b /* Check if we are done */
+ dsb ish
.if \ic != 0
+2:
+ ic \icop, x2
+ add x2, x2, x3 /* Move to the next line */
+ subs x4, x4, x3 /* Reduce the size */
+ b.hi 2b /* Check if we are done */
+ dsb ish
isb
.endif
.endm
More information about the svn-src-all
mailing list