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kernel
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linux
[PATCH] Optimize D-cache alias handling on fork
Virtually index, physically tagged cache architectures can get away
without cache flushing when forking. This patch adds a new cache
flushing function flush_cache_dup_mm(struct mm_struct *) which for the
moment I've implemented to do the same thing on all architectures
except on MIPS where it's a no-op.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
authored by Ralf Baechle and committed by Linus Torvalds ec8c0446 bcd02280
+17
-6
Documentation/cachetlb.txt
+17
-6
Documentation/cachetlb.txt
···
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lines associated with 'mm'.
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This interface is used to handle whole address space
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page table operations such as what happens during
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fork, exit, and exec.
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page table operations such as what happens during exit and exec.
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2) void flush_cache_range(struct vm_area_struct *vma,
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2) void flush_cache_dup_mm(struct mm_struct *mm)
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This interface flushes an entire user address space from
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the caches. That is, after running, there will be no cache
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lines associated with 'mm'.
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This interface is used to handle whole address space
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page table operations such as what happens during fork.
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This option is separate from flush_cache_mm to allow some
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optimizations for VIPT caches.
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3) void flush_cache_range(struct vm_area_struct *vma,
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unsigned long start, unsigned long end)
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Here we are flushing a specific range of (user) virtual
···
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call flush_cache_page (see below) for each entry which may be
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modified.
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3) void flush_cache_page(struct vm_area_struct *vma, unsigned long addr, unsigned long pfn)
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4) void flush_cache_page(struct vm_area_struct *vma, unsigned long addr, unsigned long pfn)
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This time we need to remove a PAGE_SIZE sized range
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from the cache. The 'vma' is the backing structure used by
···
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This is used primarily during fault processing.
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4) void flush_cache_kmaps(void)
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5) void flush_cache_kmaps(void)
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This routine need only be implemented if the platform utilizes
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highmem. It will be called right before all of the kmaps
···
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This routing should be implemented in asm/highmem.h
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5) void flush_cache_vmap(unsigned long start, unsigned long end)
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6) void flush_cache_vmap(unsigned long start, unsigned long end)
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void flush_cache_vunmap(unsigned long start, unsigned long end)
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Here in these two interfaces we are flushing a specific range
+1
include/asm-alpha/cacheflush.h
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include/asm-alpha/cacheflush.h
···
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/* Caches aren't brain-dead on the Alpha. */
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#define flush_cache_all() do { } while (0)
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#define flush_cache_mm(mm) do { } while (0)
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#define flush_cache_dup_mm(mm) do { } while (0)
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#define flush_cache_range(vma, start, end) do { } while (0)
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#define flush_cache_page(vma, vmaddr, pfn) do { } while (0)
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#define flush_dcache_page(page) do { } while (0)
+2
include/asm-arm/cacheflush.h
+2
include/asm-arm/cacheflush.h
+1
include/asm-arm26/cacheflush.h
+1
include/asm-arm26/cacheflush.h
···
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#define flush_cache_all() do { } while (0)
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#define flush_cache_mm(mm) do { } while (0)
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#define flush_cache_dup_mm(mm) do { } while (0)
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#define flush_cache_range(vma,start,end) do { } while (0)
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#define flush_cache_page(vma,vmaddr,pfn) do { } while (0)
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#define flush_cache_vmap(start, end) do { } while (0)
+1
include/asm-avr32/cacheflush.h
+1
include/asm-avr32/cacheflush.h
···
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*/
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#define flush_cache_all() do { } while (0)
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#define flush_cache_mm(mm) do { } while (0)
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#define flush_cache_dup_mm(mm) do { } while (0)
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#define flush_cache_range(vma, start, end) do { } while (0)
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#define flush_cache_page(vma, vmaddr, pfn) do { } while (0)
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#define flush_cache_vmap(start, end) do { } while (0)
+1
include/asm-cris/cacheflush.h
+1
include/asm-cris/cacheflush.h
···
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*/
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#define flush_cache_all() do { } while (0)
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#define flush_cache_mm(mm) do { } while (0)
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#define flush_cache_dup_mm(mm) do { } while (0)
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#define flush_cache_range(vma, start, end) do { } while (0)
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#define flush_cache_page(vma, vmaddr, pfn) do { } while (0)
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#define flush_dcache_page(page) do { } while (0)
+1
include/asm-frv/cacheflush.h
+1
include/asm-frv/cacheflush.h
···
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*/
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#define flush_cache_all() do {} while(0)
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#define flush_cache_mm(mm) do {} while(0)
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#define flush_cache_dup_mm(mm) do {} while(0)
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#define flush_cache_range(mm, start, end) do {} while(0)
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#define flush_cache_page(vma, vmaddr, pfn) do {} while(0)
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#define flush_cache_vmap(start, end) do {} while(0)
+1
include/asm-h8300/cacheflush.h
+1
include/asm-h8300/cacheflush.h
+1
include/asm-i386/cacheflush.h
+1
include/asm-i386/cacheflush.h
···
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/* Caches aren't brain-dead on the intel. */
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#define flush_cache_all() do { } while (0)
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#define flush_cache_mm(mm) do { } while (0)
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#define flush_cache_dup_mm(mm) do { } while (0)
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#define flush_cache_range(vma, start, end) do { } while (0)
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#define flush_cache_page(vma, vmaddr, pfn) do { } while (0)
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#define flush_dcache_page(page) do { } while (0)
+1
include/asm-ia64/cacheflush.h
+1
include/asm-ia64/cacheflush.h
···
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#define flush_cache_all() do { } while (0)
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#define flush_cache_mm(mm) do { } while (0)
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#define flush_cache_dup_mm(mm) do { } while (0)
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#define flush_cache_range(vma, start, end) do { } while (0)
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#define flush_cache_page(vma, vmaddr, pfn) do { } while (0)
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#define flush_icache_page(vma,page) do { } while (0)
+3
include/asm-m32r/cacheflush.h
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include/asm-m32r/cacheflush.h
···
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#if defined(CONFIG_CHIP_M32700) || defined(CONFIG_CHIP_OPSP) || defined(CONFIG_CHIP_M32104)
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#define flush_cache_all() do { } while (0)
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#define flush_cache_mm(mm) do { } while (0)
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#define flush_cache_dup_mm(mm) do { } while (0)
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#define flush_cache_range(vma, start, end) do { } while (0)
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#define flush_cache_page(vma, vmaddr, pfn) do { } while (0)
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#define flush_dcache_page(page) do { } while (0)
···
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#elif defined(CONFIG_CHIP_M32102)
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#define flush_cache_all() do { } while (0)
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#define flush_cache_mm(mm) do { } while (0)
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#define flush_cache_dup_mm(mm) do { } while (0)
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#define flush_cache_range(vma, start, end) do { } while (0)
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#define flush_cache_page(vma, vmaddr, pfn) do { } while (0)
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#define flush_dcache_page(page) do { } while (0)
···
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#else
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#define flush_cache_all() do { } while (0)
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#define flush_cache_mm(mm) do { } while (0)
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#define flush_cache_dup_mm(mm) do { } while (0)
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#define flush_cache_range(vma, start, end) do { } while (0)
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#define flush_cache_page(vma, vmaddr, pfn) do { } while (0)
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#define flush_dcache_page(page) do { } while (0)
+2
include/asm-m68k/cacheflush.h
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include/asm-m68k/cacheflush.h
···
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__flush_cache_030();
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}
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#define flush_cache_dup_mm(mm) flush_cache_mm(mm)
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/* flush_cache_range/flush_cache_page must be macros to avoid
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a dependency on linux/mm.h, which includes this file... */
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static inline void flush_cache_range(struct vm_area_struct *vma,
+1
include/asm-m68knommu/cacheflush.h
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include/asm-m68knommu/cacheflush.h
···
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#define flush_cache_all() __flush_cache_all()
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#define flush_cache_mm(mm) do { } while (0)
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#define flush_cache_dup_mm(mm) do { } while (0)
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#define flush_cache_range(vma, start, end) __flush_cache_all()
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#define flush_cache_page(vma, vmaddr) do { } while (0)
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#define flush_dcache_range(start,len) __flush_cache_all()
+2
include/asm-mips/cacheflush.h
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include/asm-mips/cacheflush.h
···
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*
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* - flush_cache_all() flushes entire cache
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* - flush_cache_mm(mm) flushes the specified mm context's cache lines
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* - flush_cache_dup mm(mm) handles cache flushing when forking
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* - flush_cache_page(mm, vmaddr, pfn) flushes a single page
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* - flush_cache_range(vma, start, end) flushes a range of pages
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* - flush_icache_range(start, end) flush a range of instructions
···
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extern void (*flush_cache_all)(void);
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extern void (*__flush_cache_all)(void);
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extern void (*flush_cache_mm)(struct mm_struct *mm);
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#define flush_cache_dup_mm(mm) do { (void) (mm); } while (0)
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extern void (*flush_cache_range)(struct vm_area_struct *vma,
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unsigned long start, unsigned long end);
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extern void (*flush_cache_page)(struct vm_area_struct *vma, unsigned long page, unsigned long pfn);
+2
include/asm-parisc/cacheflush.h
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include/asm-parisc/cacheflush.h
+1
include/asm-powerpc/cacheflush.h
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include/asm-powerpc/cacheflush.h
···
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*/
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#define flush_cache_all() do { } while (0)
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#define flush_cache_mm(mm) do { } while (0)
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#define flush_cache_dup_mm(mm) do { } while (0)
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#define flush_cache_range(vma, start, end) do { } while (0)
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#define flush_cache_page(vma, vmaddr, pfn) do { } while (0)
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#define flush_icache_page(vma, page) do { } while (0)
+1
include/asm-s390/cacheflush.h
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include/asm-s390/cacheflush.h
···
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/* Caches aren't brain-dead on the s390. */
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#define flush_cache_all() do { } while (0)
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#define flush_cache_mm(mm) do { } while (0)
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#define flush_cache_dup_mm(mm) do { } while (0)
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#define flush_cache_range(vma, start, end) do { } while (0)
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#define flush_cache_page(vma, vmaddr, pfn) do { } while (0)
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#define flush_dcache_page(page) do { } while (0)
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include/asm-sh/cpu-sh2/cacheflush.h
+2
include/asm-sh/cpu-sh2/cacheflush.h
···
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*
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* - flush_cache_all() flushes entire cache
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* - flush_cache_mm(mm) flushes the specified mm context's cache lines
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* - flush_cache_dup mm(mm) handles cache flushing when forking
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* - flush_cache_page(mm, vmaddr, pfn) flushes a single page
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* - flush_cache_range(vma, start, end) flushes a range of pages
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*
···
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*/
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#define flush_cache_all() do { } while (0)
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#define flush_cache_mm(mm) do { } while (0)
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#define flush_cache_dup_mm(mm) do { } while (0)
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#define flush_cache_range(vma, start, end) do { } while (0)
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#define flush_cache_page(vma, vmaddr, pfn) do { } while (0)
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#define flush_dcache_page(page) do { } while (0)
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include/asm-sh/cpu-sh3/cacheflush.h
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include/asm-sh/cpu-sh3/cacheflush.h
···
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*
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* - flush_cache_all() flushes entire cache
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* - flush_cache_mm(mm) flushes the specified mm context's cache lines
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* - flush_cache_dup mm(mm) handles cache flushing when forking
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* - flush_cache_page(mm, vmaddr, pfn) flushes a single page
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* - flush_cache_range(vma, start, end) flushes a range of pages
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*
···
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void flush_cache_all(void);
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void flush_cache_mm(struct mm_struct *mm);
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#define flush_cache_dup_mm(mm) flush_cache_mm(mm)
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void flush_cache_range(struct vm_area_struct *vma, unsigned long start,
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unsigned long end);
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void flush_cache_page(struct vm_area_struct *vma, unsigned long addr, unsigned long pfn);
···
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#else
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#define flush_cache_all() do { } while (0)
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#define flush_cache_mm(mm) do { } while (0)
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#define flush_cache_dup_mm(mm) do { } while (0)
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#define flush_cache_range(vma, start, end) do { } while (0)
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#define flush_cache_page(vma, vmaddr, pfn) do { } while (0)
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#define flush_dcache_page(page) do { } while (0)
+1
include/asm-sh/cpu-sh4/cacheflush.h
+1
include/asm-sh/cpu-sh4/cacheflush.h
···
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*/
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void flush_cache_all(void);
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void flush_cache_mm(struct mm_struct *mm);
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#define flush_cache_dup_mm(mm) flush_cache_mm(mm)
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void flush_cache_range(struct vm_area_struct *vma, unsigned long start,
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unsigned long end);
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void flush_cache_page(struct vm_area_struct *vma, unsigned long addr,
+2
include/asm-sh64/cacheflush.h
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include/asm-sh64/cacheflush.h
+1
include/asm-sparc/cacheflush.h
+1
include/asm-sparc/cacheflush.h
···
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#define flush_cache_all() BTFIXUP_CALL(flush_cache_all)()
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#define flush_cache_mm(mm) BTFIXUP_CALL(flush_cache_mm)(mm)
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#define flush_cache_dup_mm(mm) BTFIXUP_CALL(flush_cache_mm)(mm)
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#define flush_cache_range(vma,start,end) BTFIXUP_CALL(flush_cache_range)(vma,start,end)
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#define flush_cache_page(vma,addr,pfn) BTFIXUP_CALL(flush_cache_page)(vma,addr)
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#define flush_icache_range(start, end) do { } while (0)
+1
include/asm-sparc64/cacheflush.h
+1
include/asm-sparc64/cacheflush.h
···
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/* These are the same regardless of whether this is an SMP kernel or not. */
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#define flush_cache_mm(__mm) \
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do { if ((__mm) == current->mm) flushw_user(); } while(0)
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#define flush_cache_dup_mm(mm) flush_cache_mm(mm)
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#define flush_cache_range(vma, start, end) \
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flush_cache_mm((vma)->vm_mm)
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#define flush_cache_page(vma, page, pfn) \
+1
include/asm-v850/cacheflush.h
+1
include/asm-v850/cacheflush.h
···
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systems with MMUs, so we don't need them. */
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#define flush_cache_all() ((void)0)
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#define flush_cache_mm(mm) ((void)0)
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#define flush_cache_dup_mm(mm) ((void)0)
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#define flush_cache_range(vma, start, end) ((void)0)
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#define flush_cache_page(vma, vmaddr, pfn) ((void)0)
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#define flush_dcache_page(page) ((void)0)
+1
include/asm-x86_64/cacheflush.h
+1
include/asm-x86_64/cacheflush.h
···
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/* Caches aren't brain-dead on the intel. */
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#define flush_cache_all() do { } while (0)
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#define flush_cache_mm(mm) do { } while (0)
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#define flush_cache_dup_mm(mm) do { } while (0)
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#define flush_cache_range(vma, start, end) do { } while (0)
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#define flush_cache_page(vma, vmaddr, pfn) do { } while (0)
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#define flush_dcache_page(page) do { } while (0)
+2
include/asm-xtensa/cacheflush.h
+2
include/asm-xtensa/cacheflush.h
···
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#define flush_cache_all() __flush_invalidate_cache_all();
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#define flush_cache_mm(mm) __flush_invalidate_cache_all();
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#define flush_cache_dup_mm(mm) __flush_invalidate_cache_all();
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#define flush_cache_vmap(start,end) __flush_invalidate_cache_all();
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#define flush_cache_vunmap(start,end) __flush_invalidate_cache_all();
···
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#define flush_cache_all() do { } while (0)
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#define flush_cache_mm(mm) do { } while (0)
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#define flush_cache_dup_mm(mm) do { } while (0)
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#define flush_cache_vmap(start,end) do { } while (0)
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#define flush_cache_vunmap(start,end) do { } while (0)