This patch is presently in limbo. Should we just drop it? From: Nicolas Boichat <drinkcat@xxxxxxxxxxxx> Subject: mm: add /sys/kernel/slab/cache/cache_dma32 The patch "mm: add support for kmem caches in DMA32 zone" added support for SLAB_CACHE_DMA32 kmem caches. This patch adds the corresponding /sys/kernel/slab/cache/cache_dma32 entries, and updates the slabinfo tool. Link: http://lkml.kernel.org/r/20181210011504.122604-4-drinkcat@xxxxxxxxxxxx Signed-off-by: Nicolas Boichat <drinkcat@xxxxxxxxxxxx> Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx> Cc: Christoph Lameter <cl@xxxxxxxxx> Cc: David Rientjes <rientjes@xxxxxxxxxx> Cc: Hsin-Yi Wang <hsinyi@xxxxxxxxxxxx> Cc: Huaisheng Ye <yehs1@xxxxxxxxxx> Cc: Joerg Roedel <joro@xxxxxxxxxx> Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx> Cc: Matthias Brugger <matthias.bgg@xxxxxxxxx> Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: Mike Rapoport <rppt@xxxxxxxxxxxxxxxxxx> Cc: Pekka Enberg <penberg@xxxxxxxxxx> Cc: Robin Murphy <robin.murphy@xxxxxxx> Cc: Sasha Levin <Alexander.Levin@xxxxxxxxxxxxx> Cc: Tomasz Figa <tfiga@xxxxxxxxxx> Cc: Vlastimil Babka <vbabka@xxxxxxx> Cc: Will Deacon <will.deacon@xxxxxxx> Cc: Yingjoe Chen <yingjoe.chen@xxxxxxxxxxxx> Cc: Yong Wu <yong.wu@xxxxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- Documentation/ABI/testing/sysfs-kernel-slab | 9 +++++++++ mm/slub.c | 11 +++++++++++ tools/vm/slabinfo.c | 7 ++++++- 3 files changed, 26 insertions(+), 1 deletion(-) --- a/Documentation/ABI/testing/sysfs-kernel-slab~mm-add-sys-kernel-slab-cache-cache_dma32 +++ a/Documentation/ABI/testing/sysfs-kernel-slab @@ -106,6 +106,15 @@ Description: are from ZONE_DMA. Available when CONFIG_ZONE_DMA is enabled. +What: /sys/kernel/slab/cache/cache_dma32 +Date: December 2018 +KernelVersion: 4.21 +Contact: Nicolas Boichat <drinkcat@xxxxxxxxxxxx> +Description: + The cache_dma32 file is read-only and specifies whether objects + are from ZONE_DMA32. + Available when CONFIG_ZONE_DMA32 is enabled. + What: /sys/kernel/slab/cache/cpu_slabs Date: May 2007 KernelVersion: 2.6.22 --- a/mm/slub.c~mm-add-sys-kernel-slab-cache-cache_dma32 +++ a/mm/slub.c @@ -5112,6 +5112,14 @@ static ssize_t cache_dma_show(struct kme SLAB_ATTR_RO(cache_dma); #endif +#ifdef CONFIG_ZONE_DMA32 +static ssize_t cache_dma32_show(struct kmem_cache *s, char *buf) +{ + return sprintf(buf, "%d\n", !!(s->flags & SLAB_CACHE_DMA32)); +} +SLAB_ATTR_RO(cache_dma32); +#endif + static ssize_t usersize_show(struct kmem_cache *s, char *buf) { return sprintf(buf, "%u\n", s->usersize); @@ -5452,6 +5460,9 @@ static struct attribute *slab_attrs[] = #ifdef CONFIG_ZONE_DMA &cache_dma_attr.attr, #endif +#ifdef CONFIG_ZONE_DMA32 + &cache_dma32_attr.attr, +#endif #ifdef CONFIG_NUMA &remote_node_defrag_ratio_attr.attr, #endif --- a/tools/vm/slabinfo.c~mm-add-sys-kernel-slab-cache-cache_dma32 +++ a/tools/vm/slabinfo.c @@ -29,7 +29,7 @@ struct slabinfo { char *name; int alias; int refs; - int aliases, align, cache_dma, cpu_slabs, destroy_by_rcu; + int aliases, align, cache_dma, cache_dma32, cpu_slabs, destroy_by_rcu; unsigned int hwcache_align, object_size, objs_per_slab; unsigned int sanity_checks, slab_size, store_user, trace; int order, poison, reclaim_account, red_zone; @@ -534,6 +534,8 @@ static void report(struct slabinfo *s) printf("** Hardware cacheline aligned\n"); if (s->cache_dma) printf("** Memory is allocated in a special DMA zone\n"); + if (s->cache_dma32) + printf("** Memory is allocated in a special DMA32 zone\n"); if (s->destroy_by_rcu) printf("** Slabs are destroyed via RCU\n"); if (s->reclaim_account) @@ -602,6 +604,8 @@ static void slabcache(struct slabinfo *s *p++ = '*'; if (s->cache_dma) *p++ = 'd'; + if (s->cache_dma32) + *p++ = 'D'; if (s->hwcache_align) *p++ = 'A'; if (s->poison) @@ -1208,6 +1212,7 @@ static void read_slab_dir(void) slab->aliases = get_obj("aliases"); slab->align = get_obj("align"); slab->cache_dma = get_obj("cache_dma"); + slab->cache_dma32 = get_obj("cache_dma32"); slab->cpu_slabs = get_obj("cpu_slabs"); slab->destroy_by_rcu = get_obj("destroy_by_rcu"); slab->hwcache_align = get_obj("hwcache_align"); _