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Diffstat (limited to 'arch/tile/include/asm/homecache.h')
| -rw-r--r-- | arch/tile/include/asm/homecache.h | 125 |
1 files changed, 125 insertions, 0 deletions
diff --git a/arch/tile/include/asm/homecache.h b/arch/tile/include/asm/homecache.h new file mode 100644 index 000000000000..a8243865d49e --- /dev/null +++ b/arch/tile/include/asm/homecache.h @@ -0,0 +1,125 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + * + * Handle issues around the Tile "home cache" model of coherence. + */ + +#ifndef _ASM_TILE_HOMECACHE_H +#define _ASM_TILE_HOMECACHE_H + +#include <asm/page.h> +#include <linux/cpumask.h> + +struct page; +struct task_struct; +struct vm_area_struct; +struct zone; + +/* + * Coherence point for the page is its memory controller. + * It is not present in any cache (L1 or L2). + */ +#define PAGE_HOME_UNCACHED -1 + +/* + * Is this page immutable (unwritable) and thus able to be cached more + * widely than would otherwise be possible? On tile64 this means we + * mark the PTE to cache locally; on tilepro it means we have "nc" set. + */ +#define PAGE_HOME_IMMUTABLE -2 + +/* + * Each cpu considers its own cache to be the home for the page, + * which makes it incoherent. + */ +#define PAGE_HOME_INCOHERENT -3 + +#if CHIP_HAS_CBOX_HOME_MAP() +/* Home for the page is distributed via hash-for-home. */ +#define PAGE_HOME_HASH -4 +#endif + +/* Homing is unknown or unspecified. Not valid for page_home(). */ +#define PAGE_HOME_UNKNOWN -5 + +/* Home on the current cpu. Not valid for page_home(). */ +#define PAGE_HOME_HERE -6 + +/* Support wrapper to use instead of explicit hv_flush_remote(). */ +extern void flush_remote(unsigned long cache_pfn, unsigned long cache_length, + const struct cpumask *cache_cpumask, + HV_VirtAddr tlb_va, unsigned long tlb_length, + unsigned long tlb_pgsize, + const struct cpumask *tlb_cpumask, + HV_Remote_ASID *asids, int asidcount); + +/* Set homing-related bits in a PTE (can also pass a pgprot_t). */ +extern pte_t pte_set_home(pte_t pte, int home); + +/* Do a cache eviction on the specified cpus. */ +extern void homecache_evict(const struct cpumask *mask); + +/* + * Change a kernel page's homecache. It must not be mapped in user space. + * If !CONFIG_HOMECACHE, only usable on LOWMEM, and can only be called when + * no other cpu can reference the page, and causes a full-chip cache/TLB flush. + */ +extern void homecache_change_page_home(struct page *, int order, int home); + +/* + * Flush a page out of whatever cache(s) it is in. + * This is more than just finv, since it properly handles waiting + * for the data to reach memory on tilepro, but it can be quite + * heavyweight, particularly on hash-for-home memory. + */ +extern void homecache_flush_cache(struct page *, int order); + +/* + * Allocate a page with the given GFP flags, home, and optionally + * node. These routines are actually just wrappers around the normal + * alloc_pages() / alloc_pages_node() functions, which set and clear + * a per-cpu variable to communicate with homecache_new_kernel_page(). + * If !CONFIG_HOMECACHE, uses homecache_change_page_home(). + */ +extern struct page *homecache_alloc_pages(gfp_t gfp_mask, + unsigned int order, int home); +extern struct page *homecache_alloc_pages_node(int nid, gfp_t gfp_mask, + unsigned int order, int home); +#define homecache_alloc_page(gfp_mask, home) \ + homecache_alloc_pages(gfp_mask, 0, home) + +/* + * These routines are just pass-throughs to free_pages() when + * we support full homecaching. If !CONFIG_HOMECACHE, then these + * routines use homecache_change_page_home() to reset the home + * back to the default before returning the page to the allocator. + */ +void homecache_free_pages(unsigned long addr, unsigned int order); +#define homecache_free_page(page) \ + homecache_free_pages((page), 0) + + + +/* + * Report the page home for LOWMEM pages by examining their kernel PTE, + * or for highmem pages as the default home. + */ +extern int page_home(struct page *); + +#define homecache_migrate_kthread() do {} while (0) + +#define homecache_kpte_lock() 0 +#define homecache_kpte_unlock(flags) do {} while (0) + + +#endif /* _ASM_TILE_HOMECACHE_H */ |