Messages in this thread | | | Subject | Re: [GIT PULL v2] Early SLAB fixes for 2.6.31 | From | Pekka Enberg <> | Date | Mon, 15 Jun 2009 12:08:39 +0300 |
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On Mon, 2009-06-15 at 10:52 +0200, Nick Piggin wrote: > > Furthermore, early boot cache sysfs setup is explicitly > > handled in slab_sysfs_init() so I think we need something like the patch > > below? > > I don't think so because keventd probably comes up before sysfs > still is ready (in this respect the existing pre-early-slab code > is probably still broken but just never done such early DMA > allocations). So it just makes sense to do it all via the slab_state > flag. > > Also, if you keep the deferred flag on there for early created > slabs, then the next sysfs_add_work will try to add it again > (after slab_sysfs_init already added it). > > Here > > --- > mm/slub.c | 17 ++++++++++++++--- > 1 file changed, 14 insertions(+), 3 deletions(-) > > Index: linux-2.6/mm/slub.c > =================================================================== > --- linux-2.6.orig/mm/slub.c > +++ linux-2.6/mm/slub.c > @@ -2596,6 +2596,7 @@ static noinline struct kmem_cache *dma_k > struct kmem_cache *s; > char *text; > size_t realsize; > + unsigned long slabflags; > > s = kmalloc_caches_dma[index]; > if (s) > @@ -2617,9 +2618,18 @@ static noinline struct kmem_cache *dma_k > (unsigned int)realsize); > s = kmalloc(kmem_size, flags & ~SLUB_DMA); > > + /* > + * Must defer sysfs creation to a workqueue because we don't know > + * what context we are called from. Before sysfs comes up, we don't > + * need to do anything because slab_sysfs_init will start by > + * adding all existing slabs to sysfs. > + */ > + slabflags = SLAB_CACHE_DMA; > + if (slab_state >= SYSFS) > + slabflags |= __SYSFS_ADD_DEFERRED; > + > if (!s || !text || !kmem_cache_open(s, flags, text, > - realsize, ARCH_KMALLOC_MINALIGN, > - SLAB_CACHE_DMA|__SYSFS_ADD_DEFERRED, NULL)) { > + realsize, ARCH_KMALLOC_MINALIGN, slabflags, NULL)) { > kfree(s); > kfree(text); > goto unlock_out; > @@ -2628,7 +2638,8 @@ static noinline struct kmem_cache *dma_k > list_add(&s->list, &slab_caches); > kmalloc_caches_dma[index] = s; > > - schedule_work(&sysfs_add_work); > + if (slab_state >= SYSFS) > + schedule_work(&sysfs_add_work); > > unlock_out: > up_write(&slub_lock);
Looks good to me. Heiko, does it fix your case?
Pekka
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