On Thu, 28 Sep 2017, Yang Shi wrote:
> diff --git a/mm/slab.h b/mm/slab.h
> index 0733628..b0496d1 100644
> --- a/mm/slab.h
> +++ b/mm/slab.h
> @@ -505,6 +505,14 @@ static inline struct kmem_cache_node *get_node(struct
> kmem_cache *s, int node)
> void memcg_slab_stop(struct seq_file *m, void *p);
> int memcg_slab_show(struct seq_file *m, void *p);
>
> +#ifdef CONFIG_SLABINFO
> +void dump_unreclaimable_slab(void);
> +#else
> +static inline void dump_unreclaimable_slab(void)
> +{
> +}
> +#endif
> +
> void ___cache_free(struct kmem_cache *cache, void *x, unsigned long addr);
>
> #ifdef CONFIG_SLAB_FREELIST_RANDOM
> diff --git a/mm/slab_common.c b/mm/slab_common.c
> index 904a83b..d08213d 100644
> --- a/mm/slab_common.c
> +++ b/mm/slab_common.c
> @@ -1272,6 +1272,35 @@ static int slab_show(struct seq_file *m, void *p)
> return 0;
> }
>
> +void dump_unreclaimable_slab(void)
> +{
> + struct kmem_cache *s, *s2;
> + struct slabinfo sinfo;
> +
> + pr_info("Unreclaimable slab info:\n");
> + pr_info("Name Used Total\n");
> +
> + /*
> + * Here acquiring slab_mutex is unnecessary since we don't prefer to
> + * get sleep in oom path right before kernel panic, and avoid race
> + * condition.
> + * Since it is already oom, so there should be not any big allocation
> + * which could change the statistics significantly.
> + */
> + list_for_each_entry_safe(s, s2, &slab_caches, list) {
> + if (!is_root_cache(s) || (s->flags & SLAB_RECLAIM_ACCOUNT))
> + continue;
> +
> + memset(&sinfo, 0, sizeof(sinfo));
> + get_slabinfo(s, &sinfo);
> +
> + if (sinfo.num_objs > 0)
> + pr_info("%-17s %10luKB %10luKB\n", cache_name(s),
> + (sinfo.active_objs * s->size) / 1024,
> + (sinfo.num_objs * s->size) / 1024);
> + }
> +}
> +
> #if defined(CONFIG_MEMCG) && !defined(CONFIG_SLOB)
> void *memcg_slab_start(struct seq_file *m, loff_t *pos)
> {
>
SLABINFO is a legacy feature abd dump_unreclaimable_slab is definitely
not. It also does not depend on /proc/slabinfo support.
Please move the code out of the #ifdef CONFIG_SLABINFO section.
