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  1. 24 Aug, 2006 2 commits
    • ASANO Masahiro's avatar
      VFS: add lookup hint for network file systems · a634904a
      ASANO Masahiro authored 
      I'm trying to speeding up mkdir(2) for network file systems.  A typical
mkdir(2) calls two inode_operations: lookup and mkdir.  The lookup
operation would fail with ENOENT in common case.  I think it is unnecessary
because the subsequent mkdir operation can check it.  In case of creat(2),
lookup operation is called with the LOOKUP_CREATE flag, so individual
filesystem can omit real lookup.  e.g.  nfs_lookup().

Here is a sample patch which uses LOOKUP_CREATE and O_EXCL on mkdir,
symlink and mknod.  This uses the gadget for creat(2).

And here is the result of a benchmark on NFSv3.
  mkdir(2) 10,000 times:
    original  50.5 sec
    patched   29.0 sec
Signed-off-by: default avatarASANO Masahiro <masano@tnes.nec.co.jp>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
(cherry picked from fab7bf44449b29f9d5572a5dd8adcf7c91d5bf0f commit)
      a634904a
    • Nikita Danilov's avatar
      NFS: Fix a potential deadlock in nfs_release_page · ddeff520
      Nikita Danilov authored 
      nfs_wb_page() waits on request completion and, as a result, is not safe to be
called from nfs_release_page() invoked by VM scanner as part of GFP_NOFS
allocation. Fix possible deadlock by analyzing gfp mask and refusing to
release page if __GFP_FS is not set.
Signed-off-by: default avatarNikita Danilov <danilov@gmail.com>
Signed-off-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
(cherry picked from 374d969debfb290bafcb41d28918dc6f7e43ce31 commit)
      ddeff520
  3. 18 Aug, 2006 8 commits
  5. 17 Aug, 2006 22 commits
  7. 16 Aug, 2006 7 commits
  9. 15 Aug, 2006 1 commit
    • Hans de Goede's avatar
      [PATCH] PATCH: 1 line 2.6.18 bugfix: modpost-64bit-fix.patch · e0e92632
      Hans de Goede authored 
      There is a small but annoying bug in scripts/mod/file2alias.c which causes
it to generate invalid aliases for input devices on 64 bit archs. This causes
joydev.ko to not be automaticly loaded when inserting a joystick, resulting in
a non working joystick (for the average user).

In scripts/mod/file2alias.c is the following code for generating the input
aliases:
static void do_input(char *alias,
                     kernel_ulong_t *arr, unsigned int min, unsigned int max)
{
        unsigned int i;

        for (i = min; i < max; i++)
                if (arr[i / BITS_PER_LONG] & (1 << (i%BITS_PER_LONG)))
                        sprintf(alias + strlen(alias), "%X,*", i);
}

On 32 bits systems, this correctly generates "0,*" for the first alias, "8,*"
for the second etc.

However on 64 bits it generates: "0,*20,*" resp "8,*28,*" Notice how it adds 20
+ first entry (hex) ! to the list of hex codes, which is 32 more then the first
entry, thus is because the bit test above wraps at 32 bits instead of 64.

scripts/mod/file2alias.c, line 379 reads:
                if (arr[i / BITS_PER_LONG] & (1 << (i%BITS_PER_LONG)))
That should be:
                if (arr[i / BITS_PER_LONG] & (1L << (i%BITS_PER_LONG)))

Notice the added 'L' after the 1, otherwise that is an 32 bit int instead of a
64 bit long, and when that int gets shifted >= 32 times, appearantly the number
by which to shift is wrapped at 5 bits ( % 32) causing it to test a bit 32 bits
too low.

The patch below makes the nescesarry 1 char change :)
Signed-off-by: default avatarHans de Goede <j.w.r.degoede@hhs.nl>
Acked-by: default avatarRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
      e0e92632
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