remarkable-linux/include/asm-arm26/tlb.h
Hugh Dickins fc2acab31b [PATCH] mm: tlb_finish_mmu forget rss
zap_pte_range has been counting the pages it frees in tlb->freed, then
tlb_finish_mmu has used that to update the mm's rss.  That got stranger when I
added anon_rss, yet updated it by a different route; and stranger when rss and
anon_rss became mm_counters with special access macros.  And it would no
longer be viable if we're relying on page_table_lock to stabilize the
mm_counter, but calling tlb_finish_mmu outside that lock.

Remove the mmu_gather's freed field, let tlb_finish_mmu stick to its own
business, just decrement the rss mm_counter in zap_pte_range (yes, there was
some point to batching the update, and a subsequent patch restores that).  And
forget the anal paranoia of first reading the counter to avoid going negative
- if rss does go negative, just fix that bug.

Remove the mmu_gather's flushes and avoided_flushes from arm and arm26: no use
was being made of them.  But arm26 alone was actually using the freed, in the
way some others use need_flush: give it a need_flush.  arm26 seems to prefer
spaces to tabs here: respect that.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-29 21:40:37 -07:00

64 lines
1.9 KiB
C

#ifndef __ASMARM_TLB_H
#define __ASMARM_TLB_H
#include <asm/pgalloc.h>
#include <asm/tlbflush.h>
/*
* TLB handling. This allows us to remove pages from the page
* tables, and efficiently handle the TLB issues.
*/
struct mmu_gather {
struct mm_struct *mm;
unsigned int need_flush;
unsigned int fullmm;
};
DECLARE_PER_CPU(struct mmu_gather, mmu_gathers);
static inline struct mmu_gather *
tlb_gather_mmu(struct mm_struct *mm, unsigned int full_mm_flush)
{
struct mmu_gather *tlb = &get_cpu_var(mmu_gathers);
tlb->mm = mm;
tlb->need_flush = 0;
tlb->fullmm = full_mm_flush;
return tlb;
}
static inline void
tlb_finish_mmu(struct mmu_gather *tlb, unsigned long start, unsigned long end)
{
if (tlb->need_flush)
flush_tlb_mm(tlb->mm);
/* keep the page table cache within bounds */
check_pgt_cache();
put_cpu_var(mmu_gathers);
}
#define tlb_remove_tlb_entry(tlb,ptep,address) do { } while (0)
//#define tlb_start_vma(tlb,vma) do { } while (0)
//FIXME - ARM32 uses this now that things changed in the kernel. seems like it may be pointless on arm26, however to get things compiling...
#define tlb_start_vma(tlb,vma) \
do { \
if (!tlb->fullmm) \
flush_cache_range(vma, vma->vm_start, vma->vm_end); \
} while (0)
#define tlb_end_vma(tlb,vma) do { } while (0)
static inline void
tlb_remove_page(struct mmu_gather *tlb, struct page *page)
{
tlb->need_flush = 1;
free_page_and_swap_cache(page);
}
#define pte_free_tlb(tlb,ptep) pte_free(ptep)
#define pmd_free_tlb(tlb,pmdp) pmd_free(pmdp)
#endif