ARM: 6381/1: Use lazy cache flushing on ARMv7 SMP systems
ARMv7 processors like Cortex-A9 broadcast the cache maintenance
operations in hardware. This patch allows the
flush_dcache_page/update_mmu_cache pair to work in lazy flushing mode
similar to the UP case.
Note that cache flushing on SMP systems now takes place via the
set_pte_at() call (__sync_icache_dcache) and there is no race with other
CPUs executing code from the new PTE before the cache flushing took
place.
Tested-by: Rabin Vincent <rabin.vincent@stericsson.com>
Cc: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mm/flush.c b/arch/arm/mm/flush.c
index dd5b012..2332b77 100644
--- a/arch/arm/mm/flush.c
+++ b/arch/arm/mm/flush.c
@@ -17,6 +17,7 @@
#include <asm/smp_plat.h>
#include <asm/system.h>
#include <asm/tlbflush.h>
+#include <asm/smp_plat.h>
#include "mm.h"
@@ -93,12 +94,10 @@
#define flush_pfn_alias(pfn,vaddr) do { } while (0)
#endif
-#ifdef CONFIG_SMP
static void flush_ptrace_access_other(void *args)
{
__flush_icache_all();
}
-#endif
static
void flush_ptrace_access(struct vm_area_struct *vma, struct page *page,
@@ -122,11 +121,9 @@
if (vma->vm_flags & VM_EXEC) {
unsigned long addr = (unsigned long)kaddr;
__cpuc_coherent_kern_range(addr, addr + len);
-#ifdef CONFIG_SMP
if (cache_ops_need_broadcast())
smp_call_function(flush_ptrace_access_other,
NULL, 1);
-#endif
}
}
@@ -276,12 +273,10 @@
mapping = page_mapping(page);
-#ifndef CONFIG_SMP
- if (mapping && !mapping_mapped(mapping))
+ if (!cache_ops_need_broadcast() &&
+ mapping && !mapping_mapped(mapping))
clear_bit(PG_dcache_clean, &page->flags);
- else
-#endif
- {
+ else {
__flush_dcache_page(mapping, page);
if (mapping && cache_is_vivt())
__flush_dcache_aliases(mapping, page);
