reduce tlb/cache flush times of agpgart memory allocation

To reduce tlb/cache flush, makes agp memory allocation do one flush
after all pages in a region are changed to uc.

All agp drivers except agp-sgi uses agp_generic_alloc_page()
for .agp_alloc_page, so the patch should work for them. agp-sgi is only
for ia64, so not a problem too.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Cc: airlied@linux.ie
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Shaohua Li 2008-08-04 14:51:30 +08:00 committed by Ingo Molnar
parent 1ac2f7d55b
commit 466ae83742
3 changed files with 10 additions and 1 deletions

View File

@ -30,6 +30,10 @@
#define _AGP_BACKEND_PRIV_H 1
#include <asm/agp.h> /* for flush_agp_cache() */
#ifndef map_page_into_agp_noflush
#define map_page_into_agp_noflush(page) map_page_into_agp(page)
#define map_page_into_agp_global_flush()
#endif
#define PFX "agpgart: "

View File

@ -274,6 +274,7 @@ struct agp_memory *agp_allocate_memory(struct agp_bridge_data *bridge,
new->memory[i] = virt_to_gart(addr);
new->page_count++;
}
map_page_into_agp_global_flush();
new->bridge = bridge;
return new;
@ -1186,7 +1187,8 @@ void *agp_generic_alloc_page(struct agp_bridge_data *bridge)
if (page == NULL)
return NULL;
map_page_into_agp(page);
/* agp_allocate_memory will do flush */
map_page_into_agp_noflush(page);
get_page(page);
atomic_inc(&agp_bridge->current_memory_agp);

View File

@ -15,6 +15,9 @@
#define map_page_into_agp(page) set_pages_uc(page, 1)
#define unmap_page_from_agp(page) set_pages_wb(page, 1)
#define map_page_into_agp_noflush(page) set_pages_uc_noflush(page, 1)
#define map_page_into_agp_global_flush() set_memory_flush_all()
/*
* Could use CLFLUSH here if the cpu supports it. But then it would
* need to be called for each cacheline of the whole page so it may