Eric Lee / smarc-fsl-linux-kernel

16 Sep, 2009

1 commit

  • dca230f00   ARM: 5701/1: ARM: copy_page.S: take into account the size of the cache line ... Browse Code »

    Optimized version of copy_page() was written with assumption that cache
    line size is 32 bytes. On Cortex-A8 cache line size is 64 bytes.

    This patch tries to generalize copy_page() to work with any cache line
    size if cache line size is multiple of 16 and page size is multiple of
    two cache line size.

    After this optimization we've got ~25% speedup on OMAP3(tested in
    userspace).

    There is test for kernelspace which trigger copy-on-write after fork():

    #include
    #include
    #include

    #define BUF_SIZE (10000*4096)
    #define NFORK 200

    int main(int argc, char **argv)
    {
    char *buf = malloc(BUF_SIZE);
    int i;

    memset(buf, 0, BUF_SIZE);

    for(i = 0; i < NFORK; i++) {
    if (fork()) {
    wait(NULL);
    } else {
    int j;

    for(j = 0; j < BUF_SIZE; j+= 4096)
    buf[j] = (j & 0xFF) + 1;
    break;
    }
    }

    free(buf);
    return 0;
    }

    Before optimization this test takes ~66 seconds, after optimization
    takes ~56 seconds.

    Signed-off-by: Siarhei Siamashka
    Signed-off-by: Kirill A. Shutemov
    Signed-off-by: Russell King

    Kirill A. Shutemov
     

01 Sep, 2008

1 commit

25 Jun, 2006

1 commit

10 Sep, 2005

1 commit

17 Apr, 2005

1 commit

  • 1da177e4c   Linux-2.6.12-rc2 ... Browse Code »

    Initial git repository build. I'm not bothering with the full history,
    even though we have it. We can create a separate "historical" git
    archive of that later if we want to, and in the meantime it's about
    3.2GB when imported into git - space that would just make the early
    git days unnecessarily complicated, when we don't have a lot of good
    infrastructure for it.

    Let it rip!

    Linus Torvalds