linux/arch/ia64/sn/kernel/sn2/cache.c
Dean Nelson 929f97276b [PATCH] change gen_pool allocator to not touch managed memory
Modify the gen_pool allocator (lib/genalloc.c) to utilize a bitmap scheme
instead of the buddy scheme.  The purpose of this change is to eliminate
the touching of the actual memory being allocated.

Since the change modifies the interface, a change to the uncached allocator
(arch/ia64/kernel/uncached.c) is also required.

Both Andrey Volkov and Jes Sorenson have expressed a desire that the
gen_pool allocator not write to the memory being managed. See the
following:

  http://marc.theaimsgroup.com/?l=linux-kernel&m=113518602713125&w=2
  http://marc.theaimsgroup.com/?l=linux-kernel&m=113533568827916&w=2

Signed-off-by: Dean Nelson <dcn@sgi.com>
Cc: Andrey Volkov <avolkov@varma-el.com>
Acked-by: Jes Sorensen <jes@trained-monkey.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23 07:42:49 -07:00

42 lines
1.2 KiB
C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2001-2003, 2006 Silicon Graphics, Inc. All rights reserved.
*
*/
#include <linux/module.h>
#include <asm/pgalloc.h>
#include <asm/sn/arch.h>
/**
* sn_flush_all_caches - flush a range of address from all caches (incl. L4)
* @flush_addr: identity mapped region 7 address to start flushing
* @bytes: number of bytes to flush
*
* Flush a range of addresses from all caches including L4.
* All addresses fully or partially contained within
* @flush_addr to @flush_addr + @bytes are flushed
* from all caches.
*/
void
sn_flush_all_caches(long flush_addr, long bytes)
{
unsigned long addr = flush_addr;
/* SHub1 requires a cached address */
if (is_shub1() && (addr & RGN_BITS) == RGN_BASE(RGN_UNCACHED))
addr = (addr - RGN_BASE(RGN_UNCACHED)) + RGN_BASE(RGN_KERNEL);
flush_icache_range(addr, addr + bytes);
/*
* The last call may have returned before the caches
* were actually flushed, so we call it again to make
* sure.
*/
flush_icache_range(addr, addr + bytes);
mb();
}
EXPORT_SYMBOL(sn_flush_all_caches);