Commit 605f315c authored by John David Anglin's avatar John David Anglin Committed by Greg Kroah-Hartman

parisc: Remove unnecessary TLB purges from flush_dcache_page_asm and flush_icache_page_asm

commit febe4296 upstream.

We have four routines in pacache.S that use temporary alias pages:
copy_user_page_asm(), clear_user_page_asm(), flush_dcache_page_asm() and
flush_icache_page_asm().  copy_user_page_asm() and clear_user_page_asm()
don't purge the TLB entry used for the operation.
flush_dcache_page_asm() and flush_icache_page_asm do purge the entry.

Presumably, this was thought to optimize TLB use.  However, the
operation is quite heavy weight on PA 1.X processors as we need to take
the TLB lock and a TLB broadcast is sent to all processors.

This patch removes the purges from flush_dcache_page_asm() and
flush_icache_page_asm.
Signed-off-by: default avatarJohn David Anglin  <dave.anglin@bell.net>
Signed-off-by: default avatarHelge Deller <deller@gmx.de>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent db959860
......@@ -886,19 +886,10 @@ ENTRY(flush_dcache_page_asm)
fdc,m r31(%r28)
fdc,m r31(%r28)
fdc,m r31(%r28)
cmpb,COND(<<) %r28, %r25,1b
cmpb,COND(<<) %r28, %r25,1b
fdc,m r31(%r28)
sync
#ifdef CONFIG_PA20
pdtlb,l %r0(%r25)
#else
tlb_lock %r20,%r21,%r22
pdtlb %r0(%r25)
tlb_unlock %r20,%r21,%r22
#endif
bv %r0(%r2)
nop
.exit
......@@ -973,17 +964,6 @@ ENTRY(flush_icache_page_asm)
fic,m %r31(%sr4,%r28)
sync
#ifdef CONFIG_PA20
pdtlb,l %r0(%r28)
pitlb,l %r0(%sr4,%r25)
#else
tlb_lock %r20,%r21,%r22
pdtlb %r0(%r28)
pitlb %r0(%sr4,%r25)
tlb_unlock %r20,%r21,%r22
#endif
bv %r0(%r2)
nop
.exit
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment