A previous patch in this series adds support for SLAB_CACHE_DMA32 kmem caches. This adds the corresponding /sys/kernel/slab/cache/cache_dma32 entries, and fixes slabinfo tool.
Cc: stable@vger.kernel.org Signed-off-by: Nicolas Boichat drinkcat@chromium.org ---
There were different opinions on whether this sysfs entry should be added, so I'll leave it up to the mm/slub maintainers to decide whether they want to pick this up, or drop it.
No change since v5.
Documentation/ABI/testing/sysfs-kernel-slab | 9 +++++++++ mm/slub.c | 11 +++++++++++ tools/vm/slabinfo.c | 7 ++++++- 3 files changed, 26 insertions(+), 1 deletion(-)
diff --git a/Documentation/ABI/testing/sysfs-kernel-slab b/Documentation/ABI/testing/sysfs-kernel-slab index 29601d93a1c2ea..d742c6cfdffbe9 100644 --- a/Documentation/ABI/testing/sysfs-kernel-slab +++ b/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@chromium.org +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 diff --git a/mm/slub.c b/mm/slub.c index 4caadb926838ef..840f3719d9d543 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -5104,6 +5104,14 @@ static ssize_t cache_dma_show(struct kmem_cache *s, char *buf) 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); @@ -5444,6 +5452,9 @@ 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 diff --git a/tools/vm/slabinfo.c b/tools/vm/slabinfo.c index 334b16db0ebbe9..4ee1bf6e498dfa 100644 --- a/tools/vm/slabinfo.c +++ b/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; @@ -531,6 +531,8 @@ 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) @@ -599,6 +601,8 @@ 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) @@ -1205,6 +1209,7 @@ 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");