lkml.org 
[lkml]   [2010]   [Jul]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    SubjectRe: [Intel-gfx] [PATCH] drm/i915: Selectively enable self-reclaim
    From
    On Thu, Jul 1, 2010 at 11:24 AM, Linus Torvalds
    <torvalds@linux-foundation.org> wrote:
    > On Wed, Jun 30, 2010 at 4:07 PM, Linus Torvalds
    > <torvalds@linux-foundation.org> wrote:
    >>
    >> That commit changes the page cache allocation to use
    >>
    >> +                                          mapping_gfp_mask (mapping) |
    >> +                                          __GFP_COLD |
    >> +                                          gfpmask);
    >>
    >> if I read it right. And the default mapping_gfp_mask() is
    >> GFP_HIGHUSER_MOVABLE, so I think you get all of
    >> (__GFP_WAIT | __GFP_IO | __GFP_FS | __GFP_HARDWALL | __GFP_HIGHMEM)
    >> set by default.
    >
    > .. and then I left out the one flag I _meant_ to have there, namely
    > __GFP_MOVABLE.
    >
    >> The old code didn't just play games with ~__GFP_NORETRY and change
    >> that at runtime (which was buggy - no locking, no protection, no
    >> nothing), it also initialized the gfp mask. And that code also got
    >> removed:
    >
    > In fact, I don't really see why we should use that mapping_gfp_mask()
    > at all, since all allocations should be going through that
    > i915_gem_object_get_pages() function anyway. So why not just change
    > that function to ignore the default gfp mask for the mapping, and just
    > use the mask that the o915 driver wants?
    >
    > Btw, why did it want to mark the pages reclaimable?
    >
    > Anyway, what I'm suggesting somebody who sees this test is just
    > something like the patch below (whitespace-damage - I'm cutting and
    > pasting, it's a trivial one-liner).  Does this change any behavior?
    > Vefa?
    >

    I think Linus is on to something, I'll finish my testing tomorrow,

    I'm stuck testing this on a laptop with a 4200rpm driver, hibernating
    takes quite a long time ;-(

    But I have reproduced the initial failure,reverted the patch
    reproduced success, and then did a couple of cycles with Linus patch
    before I left.

    Tomorrow I'll do another 3-4 cycles to confirm.

    the patch also needs a couple of __ before GFP_HIGHMEM, in case
    anyone else was hacking it.

    Dave.


    >                    Linus
    >
    > ---
    > diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
    > index 9ded3da..ec8ed6b 100644
    > --- a/drivers/gpu/drm/i915/i915_gem.c
    > +++ b/drivers/gpu/drm/i915/i915_gem.c
    > @@ -2239,7 +2239,7 @@ i915_gem_object_get_pages(struct drm_gem_object *obj,
    >        mapping = inode->i_mapping;
    >        for (i = 0; i < page_count; i++) {
    >                page = read_cache_page_gfp(mapping, i,
    > -                                          mapping_gfp_mask (mapping) |
    > +                                          GFP_HIGHMEM |
    >                                           __GFP_COLD |
    >                                           gfpmask);
    >                if (IS_ERR(page))
    > --
    > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    > the body of a message to majordomo@vger.kernel.org
    > More majordomo info at  http://vger.kernel.org/majordomo-info.html
    > Please read the FAQ at  http://www.tux.org/lkml/
    >
    --
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2010-07-01 12:17    [W:0.028 / U:148.160 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site