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: John David Anglin <dave.anglin@xxxxxxxx>
diff --git a/arch/parisc/kernel/pacache.S b/arch/parisc/kernel/pacache.S index b743a80..41a923d 100644 --- a/arch/parisc/kernel/pacache.S +++ b/arch/parisc/kernel/pacache.S @@ -886,19 +892,10 @@ 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 0(%r25) -#else - tlb_lock %r20,%r21,%r22 - pdtlb 0(%r25) - tlb_unlock %r20,%r21,%r22 -#endif - bv %r0(%r2) nop .exit @@ -968,15 +970,6 @@ ENTRY(flush_icache_page_asm) fic,m %r31(%sr4,%r28) sync - -#ifdef CONFIG_PA20 - pitlb,l %r0(%sr4,%r25) -#else - tlb_lock %r20,%r21,%r22 - pitlb (%sr4,%r25) - tlb_unlock %r20,%r21,%r22 -#endif - bv %r0(%r2) nop .exit
-- John David Anglin dave.anglin@xxxxxxxx
