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| author | David S. Miller <davem@davemloft.net> | 2005-04-18 05:03:11 +0400 |
|---|---|---|
| committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-18 05:03:11 +0400 |
| commit | dadeafdfc8da8c27e5a68e0706b9856eaac89391 (patch) | |
| tree | 17993d26e93e598a2f449063fe213afad2a45814 /include/asm-sparc64 | |
| parent | fb65b9619b756793d824df7501c895a2c2871f40 (diff) | |
| download | linux-dadeafdfc8da8c27e5a68e0706b9856eaac89391.tar.xz | |
[PATCH] sparc64: Reduce ptrace cache flushing
We were flushing the D-cache excessively for ptrace() processing
and this makes debugging threads so slow as to be totally unusable.
All process page accesses via ptrace() go via access_process_vm().
This routine, for each process page, uses get_user_pages(). That
in turn does a flush_dcache_page() on the child pages before we
copy in/out the ptrace request data.
Therefore, all we need to do after the data movement is:
1) Flush the D-cache pages if the kernel maps the page to a different
color than userspace does.
2) If we wrote to the page, we need to flush the I-cache on older cpus.
Previously we just flushed the entire cache at the end of a ptrace()
request, and that was beyond stupid.
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'include/asm-sparc64')
| -rw-r--r-- | include/asm-sparc64/cacheflush.h | 22 |
1 files changed, 14 insertions, 8 deletions
diff --git a/include/asm-sparc64/cacheflush.h b/include/asm-sparc64/cacheflush.h index 86f02937ff1b..51b26e81d828 100644 --- a/include/asm-sparc64/cacheflush.h +++ b/include/asm-sparc64/cacheflush.h @@ -49,16 +49,22 @@ extern void flush_dcache_page(struct page *page); #define flush_icache_page(vma, pg) do { } while(0) #define flush_icache_user_range(vma,pg,adr,len) do { } while (0) -#define copy_to_user_page(vma, page, vaddr, dst, src, len) \ - do { \ - flush_cache_page(vma, vaddr, page_to_pfn(page));\ - memcpy(dst, src, len); \ +extern void flush_ptrace_access(struct vm_area_struct *, struct page *, + unsigned long uaddr, void *kaddr, + unsigned long len, int write); + +#define copy_to_user_page(vma, page, vaddr, dst, src, len) \ + do { \ + flush_cache_page(vma, vaddr, page_to_pfn(page)); \ + memcpy(dst, src, len); \ + flush_ptrace_access(vma, page, vaddr, src, len, 0); \ } while (0) -#define copy_from_user_page(vma, page, vaddr, dst, src, len) \ - do { \ - flush_cache_page(vma, vaddr, page_to_pfn(page));\ - memcpy(dst, src, len); \ +#define copy_from_user_page(vma, page, vaddr, dst, src, len) \ + do { \ + flush_cache_page(vma, vaddr, page_to_pfn(page)); \ + memcpy(dst, src, len); \ + flush_ptrace_access(vma, page, vaddr, dst, len, 1); \ } while (0) #define flush_dcache_mmap_lock(mapping) do { } while (0) |