The patch titled Subject: mm/slub.c: add comments to endif pre-processor macros has been added to the -mm tree. Its filename is slub-add-comments-to-endif-pre-processor-macros.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/slub-add-comments-to-endif-pre-processor-macros.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/slub-add-comments-to-endif-pre-processor-macros.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: "Tobin C. Harding" <tobin@xxxxxxxxxx> Subject: mm/slub.c: add comments to endif pre-processor macros SLUB allocator makes heavy use of ifdef/endif pre-processor macros. The pairing of these statements is at times hard to follow e.g. if the pair are further than a screen apart or if there are nested pairs. We can reduce cognitive load by adding a comment to the endif statement of form #ifdef CONFIG_FOO ... #endif /* CONFIG_FOO */ Add comments to endif pre-processor macros if ifdef/endif pair is not immediately apparent. Link: http://lkml.kernel.org/r/20190318000234.22049-5-tobin@xxxxxxxxxx Signed-off-by: Tobin C. Harding <tobin@xxxxxxxxxx> Acked-by: Christoph Lameter <cl@xxxxxxxxx> Cc: David Rientjes <rientjes@xxxxxxxxxx> Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Cc: Pekka Enberg <penberg@xxxxxxxxxx> Cc: Roman Gushchin <guro@xxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/slub.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) --- a/mm/slub.c~slub-add-comments-to-endif-pre-processor-macros +++ a/mm/slub.c @@ -1951,7 +1951,7 @@ static void *get_any_partial(struct kmem } } } while (read_mems_allowed_retry(cpuset_mems_cookie)); -#endif +#endif /* CONFIG_NUMA */ return NULL; } @@ -2249,7 +2249,7 @@ static void unfreeze_partials(struct kme discard_slab(s, page); stat(s, FREE_SLAB); } -#endif +#endif /* CONFIG_SLUB_CPU_PARTIAL */ } /* @@ -2308,7 +2308,7 @@ static void put_cpu_partial(struct kmem_ local_irq_restore(flags); } preempt_enable(); -#endif +#endif /* CONFIG_SLUB_CPU_PARTIAL */ } static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c) @@ -2813,7 +2813,7 @@ void *kmem_cache_alloc_node_trace(struct } EXPORT_SYMBOL(kmem_cache_alloc_node_trace); #endif -#endif +#endif /* CONFIG_NUMA */ /* * Slow path handling. This may still be called frequently since objects @@ -3848,7 +3848,7 @@ void *__kmalloc_node(size_t size, gfp_t return ret; } EXPORT_SYMBOL(__kmalloc_node); -#endif +#endif /* CONFIG_NUMA */ #ifdef CONFIG_HARDENED_USERCOPY /* @@ -4066,7 +4066,7 @@ void __kmemcg_cache_deactivate(struct km */ slab_deactivate_memcg_cache_rcu_sched(s, kmemcg_cache_deact_after_rcu); } -#endif +#endif /* CONFIG_MEMCG */ static int slab_mem_going_offline_callback(void *arg) { @@ -4699,7 +4699,7 @@ static int list_locations(struct kmem_ca len += sprintf(buf, "No data\n"); return len; } -#endif +#endif /* CONFIG_SLUB_DEBUG */ #ifdef SLUB_RESILIENCY_TEST static void __init resiliency_test(void) @@ -4759,7 +4759,7 @@ static void __init resiliency_test(void) #ifdef CONFIG_SYSFS static void resiliency_test(void) {}; #endif -#endif +#endif /* SLUB_RESILIENCY_TEST */ #ifdef CONFIG_SYSFS enum slab_stat_type { @@ -5424,7 +5424,7 @@ STAT_ATTR(CPU_PARTIAL_ALLOC, cpu_partial STAT_ATTR(CPU_PARTIAL_FREE, cpu_partial_free); STAT_ATTR(CPU_PARTIAL_NODE, cpu_partial_node); STAT_ATTR(CPU_PARTIAL_DRAIN, cpu_partial_drain); -#endif +#endif /* CONFIG_SLUB_STATS */ static struct attribute *slab_attrs[] = { &slab_size_attr.attr, @@ -5628,7 +5628,7 @@ static void memcg_propagate_slab_attrs(s if (buffer) free_page((unsigned long)buffer); -#endif +#endif /* CONFIG_MEMCG */ } static void kmem_cache_release(struct kobject *k) _ Patches currently in -mm which might be from tobin@xxxxxxxxxx are list-add-function-list_rotate_to_front.patch slob-respect-list_head-abstraction-layer.patch slob-use-slab_list-instead-of-lru.patch slub-add-comments-to-endif-pre-processor-macros.patch slub-use-slab_list-instead-of-lru.patch slab-use-slab_list-instead-of-lru.patch mm-remove-stale-comment-from-page-struct.patch