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Subject: Re: [PATCH 1/2] mm: slab/slub: use raw_spinlock_t to define list_lock
To:     Yejune Deng <yejune.deng@gmail.com>, cl@linux.com,
        penberg@kernel.org, rientjes@google.com, iamjoonsoo.kim@lge.com,
        akpm@linux-foundation.org, Thomas Gleixner <tglx@linutronix.de>,
        Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        Yejune Deng <yejunedeng@gmail.com>
References: <1621938235-11947-1-git-send-email-yejunedeng@gmail.com>
From:   Vlastimil Babka <vbabka@suse.cz>
Message-ID: <af94a886-ceda-f701-742a-68c98b04c672@suse.cz>
Date:   Tue, 25 May 2021 12:43:01 +0200
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Precedence: bulk

On 5/25/21 12:23 PM, Yejune Deng wrote:
> Use raw_spinlock_t instead of spinlock_t to define list_lock
> that won't be preempted on mainline and PREEMPT_RT kernels.
> 
> Signed-off-by: Yejune Deng <yejunedeng@gmail.com>

Yeah, RT tree already has such patch, but with more thorough changelog:

https://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git/tree/patches/0001-mm-sl-au-b-Change-list_lock-to-raw_spinlock_t.patch?h=linux-5.12.y-rt-patches

But I think the SLAB part is unnecessary, as there's also a patch
restricting RT to SLUB only.
And for SLUB I just posted a series towards making the conversion to
raw_spinlock_t unnecessary:

https://lore.kernel.org/linux-mm/20210524233946.20352-1-vbabka@suse.cz/

> ---
>  mm/slab.c | 90 +++++++++++++++++++++++++++++++--------------------------------
>  mm/slab.h |  2 +-
>  mm/slub.c | 50 +++++++++++++++++------------------
>  3 files changed, 71 insertions(+), 71 deletions(-)
> 
> diff --git a/mm/slab.c b/mm/slab.c
> index d0f7256..ae54677 100644
> --- a/mm/slab.c
> +++ b/mm/slab.c
> @@ -234,7 +234,7 @@ static void kmem_cache_node_init(struct kmem_cache_node *parent)
>  	parent->shared = NULL;
>  	parent->alien = NULL;
>  	parent->colour_next = 0;
> -	spin_lock_init(&parent->list_lock);
> +	raw_spin_lock_init(&parent->list_lock);
>  	parent->free_objects = 0;
>  	parent->free_touched = 0;
>  }
> @@ -559,9 +559,9 @@ static noinline void cache_free_pfmemalloc(struct kmem_cache *cachep,
>  	page_node = page_to_nid(page);
>  	n = get_node(cachep, page_node);
>  
> -	spin_lock(&n->list_lock);
> +	raw_spin_lock(&n->list_lock);
>  	free_block(cachep, &objp, 1, page_node, &list);
> -	spin_unlock(&n->list_lock);
> +	raw_spin_unlock(&n->list_lock);
>  
>  	slabs_destroy(cachep, &list);
>  }
> @@ -699,7 +699,7 @@ static void __drain_alien_cache(struct kmem_cache *cachep,
>  	struct kmem_cache_node *n = get_node(cachep, node);
>  
>  	if (ac->avail) {
> -		spin_lock(&n->list_lock);
> +		raw_spin_lock(&n->list_lock);
>  		/*
>  		 * Stuff objects into the remote nodes shared array first.
>  		 * That way we could avoid the overhead of putting the objects
> @@ -710,7 +710,7 @@ static void __drain_alien_cache(struct kmem_cache *cachep,
>  
>  		free_block(cachep, ac->entry, ac->avail, node, list);
>  		ac->avail = 0;
> -		spin_unlock(&n->list_lock);
> +		raw_spin_unlock(&n->list_lock);
>  	}
>  }
>  
> @@ -783,9 +783,9 @@ static int __cache_free_alien(struct kmem_cache *cachep, void *objp,
>  		slabs_destroy(cachep, &list);
>  	} else {
>  		n = get_node(cachep, page_node);
> -		spin_lock(&n->list_lock);
> +		raw_spin_lock(&n->list_lock);
>  		free_block(cachep, &objp, 1, page_node, &list);
> -		spin_unlock(&n->list_lock);
> +		raw_spin_unlock(&n->list_lock);
>  		slabs_destroy(cachep, &list);
>  	}
>  	return 1;
> @@ -826,10 +826,10 @@ static int init_cache_node(struct kmem_cache *cachep, int node, gfp_t gfp)
>  	 */
>  	n = get_node(cachep, node);
>  	if (n) {
> -		spin_lock_irq(&n->list_lock);
> +		raw_spin_lock_irq(&n->list_lock);
>  		n->free_limit = (1 + nr_cpus_node(node)) * cachep->batchcount +
>  				cachep->num;
> -		spin_unlock_irq(&n->list_lock);
> +		raw_spin_unlock_irq(&n->list_lock);
>  
>  		return 0;
>  	}
> @@ -908,7 +908,7 @@ static int setup_kmem_cache_node(struct kmem_cache *cachep,
>  		goto fail;
>  
>  	n = get_node(cachep, node);
> -	spin_lock_irq(&n->list_lock);
> +	raw_spin_lock_irq(&n->list_lock);
>  	if (n->shared && force_change) {
>  		free_block(cachep, n->shared->entry,
>  				n->shared->avail, node, &list);
> @@ -926,7 +926,7 @@ static int setup_kmem_cache_node(struct kmem_cache *cachep,
>  		new_alien = NULL;
>  	}
>  
> -	spin_unlock_irq(&n->list_lock);
> +	raw_spin_unlock_irq(&n->list_lock);
>  	slabs_destroy(cachep, &list);
>  
>  	/*
> @@ -965,7 +965,7 @@ static void cpuup_canceled(long cpu)
>  		if (!n)
>  			continue;
>  
> -		spin_lock_irq(&n->list_lock);
> +		raw_spin_lock_irq(&n->list_lock);
>  
>  		/* Free limit for this kmem_cache_node */
>  		n->free_limit -= cachep->batchcount;
> @@ -976,7 +976,7 @@ static void cpuup_canceled(long cpu)
>  		nc->avail = 0;
>  
>  		if (!cpumask_empty(mask)) {
> -			spin_unlock_irq(&n->list_lock);
> +			raw_spin_unlock_irq(&n->list_lock);
>  			goto free_slab;
>  		}
>  
> @@ -990,7 +990,7 @@ static void cpuup_canceled(long cpu)
>  		alien = n->alien;
>  		n->alien = NULL;
>  
> -		spin_unlock_irq(&n->list_lock);
> +		raw_spin_unlock_irq(&n->list_lock);
>  
>  		kfree(shared);
>  		if (alien) {
> @@ -1174,7 +1174,7 @@ static void __init init_list(struct kmem_cache *cachep, struct kmem_cache_node *
>  	/*
>  	 * Do not assume that spinlocks can be initialized via memcpy:
>  	 */
> -	spin_lock_init(&ptr->list_lock);
> +	raw_spin_lock_init(&ptr->list_lock);
>  
>  	MAKE_ALL_LISTS(cachep, ptr, nodeid);
>  	cachep->node[nodeid] = ptr;
> @@ -1345,11 +1345,11 @@ slab_out_of_memory(struct kmem_cache *cachep, gfp_t gfpflags, int nodeid)
>  	for_each_kmem_cache_node(cachep, node, n) {
>  		unsigned long total_slabs, free_slabs, free_objs;
>  
> -		spin_lock_irqsave(&n->list_lock, flags);
> +		raw_spin_lock_irqsave(&n->list_lock, flags);
>  		total_slabs = n->total_slabs;
>  		free_slabs = n->free_slabs;
>  		free_objs = n->free_objects;
> -		spin_unlock_irqrestore(&n->list_lock, flags);
> +		raw_spin_unlock_irqrestore(&n->list_lock, flags);
>  
>  		pr_warn("  node %d: slabs: %ld/%ld, objs: %ld/%ld\n",
>  			node, total_slabs - free_slabs, total_slabs,
> @@ -2107,7 +2107,7 @@ static void check_spinlock_acquired(struct kmem_cache *cachep)
>  {
>  #ifdef CONFIG_SMP
>  	check_irq_off();
> -	assert_spin_locked(&get_node(cachep, numa_mem_id())->list_lock);
> +	assert_raw_spin_locked(&get_node(cachep, numa_mem_id())->list_lock);
>  #endif
>  }
>  
> @@ -2115,7 +2115,7 @@ static void check_spinlock_acquired_node(struct kmem_cache *cachep, int node)
>  {
>  #ifdef CONFIG_SMP
>  	check_irq_off();
> -	assert_spin_locked(&get_node(cachep, node)->list_lock);
> +	assert_raw_spin_locked(&get_node(cachep, node)->list_lock);
>  #endif
>  }
>  
> @@ -2155,9 +2155,9 @@ static void do_drain(void *arg)
>  	check_irq_off();
>  	ac = cpu_cache_get(cachep);
>  	n = get_node(cachep, node);
> -	spin_lock(&n->list_lock);
> +	raw_spin_lock(&n->list_lock);
>  	free_block(cachep, ac->entry, ac->avail, node, &list);
> -	spin_unlock(&n->list_lock);
> +	raw_spin_unlock(&n->list_lock);
>  	ac->avail = 0;
>  	slabs_destroy(cachep, &list);
>  }
> @@ -2175,9 +2175,9 @@ static void drain_cpu_caches(struct kmem_cache *cachep)
>  			drain_alien_cache(cachep, n->alien);
>  
>  	for_each_kmem_cache_node(cachep, node, n) {
> -		spin_lock_irq(&n->list_lock);
> +		raw_spin_lock_irq(&n->list_lock);
>  		drain_array_locked(cachep, n->shared, node, true, &list);
> -		spin_unlock_irq(&n->list_lock);
> +		raw_spin_unlock_irq(&n->list_lock);
>  
>  		slabs_destroy(cachep, &list);
>  	}
> @@ -2199,10 +2199,10 @@ static int drain_freelist(struct kmem_cache *cache,
>  	nr_freed = 0;
>  	while (nr_freed < tofree && !list_empty(&n->slabs_free)) {
>  
> -		spin_lock_irq(&n->list_lock);
> +		raw_spin_lock_irq(&n->list_lock);
>  		p = n->slabs_free.prev;
>  		if (p == &n->slabs_free) {
> -			spin_unlock_irq(&n->list_lock);
> +			raw_spin_unlock_irq(&n->list_lock);
>  			goto out;
>  		}
>  
> @@ -2215,7 +2215,7 @@ static int drain_freelist(struct kmem_cache *cache,
>  		 * to the cache.
>  		 */
>  		n->free_objects -= cache->num;
> -		spin_unlock_irq(&n->list_lock);
> +		raw_spin_unlock_irq(&n->list_lock);
>  		slab_destroy(cache, page);
>  		nr_freed++;
>  	}
> @@ -2651,7 +2651,7 @@ static void cache_grow_end(struct kmem_cache *cachep, struct page *page)
>  	INIT_LIST_HEAD(&page->slab_list);
>  	n = get_node(cachep, page_to_nid(page));
>  
> -	spin_lock(&n->list_lock);
> +	raw_spin_lock(&n->list_lock);
>  	n->total_slabs++;
>  	if (!page->active) {
>  		list_add_tail(&page->slab_list, &n->slabs_free);
> @@ -2661,7 +2661,7 @@ static void cache_grow_end(struct kmem_cache *cachep, struct page *page)
>  
>  	STATS_INC_GROWN(cachep);
>  	n->free_objects += cachep->num - page->active;
> -	spin_unlock(&n->list_lock);
> +	raw_spin_unlock(&n->list_lock);
>  
>  	fixup_objfreelist_debug(cachep, &list);
>  }
> @@ -2827,7 +2827,7 @@ static struct page *get_first_slab(struct kmem_cache_node *n, bool pfmemalloc)
>  {
>  	struct page *page;
>  
> -	assert_spin_locked(&n->list_lock);
> +	assert_raw_spin_locked(&n->list_lock);
>  	page = list_first_entry_or_null(&n->slabs_partial, struct page,
>  					slab_list);
>  	if (!page) {
> @@ -2854,10 +2854,10 @@ static noinline void *cache_alloc_pfmemalloc(struct kmem_cache *cachep,
>  	if (!gfp_pfmemalloc_allowed(flags))
>  		return NULL;
>  
> -	spin_lock(&n->list_lock);
> +	raw_spin_lock(&n->list_lock);
>  	page = get_first_slab(n, true);
>  	if (!page) {
> -		spin_unlock(&n->list_lock);
> +		raw_spin_unlock(&n->list_lock);
>  		return NULL;
>  	}
>  
> @@ -2866,7 +2866,7 @@ static noinline void *cache_alloc_pfmemalloc(struct kmem_cache *cachep,
>  
>  	fixup_slab_list(cachep, n, page, &list);
>  
> -	spin_unlock(&n->list_lock);
> +	raw_spin_unlock(&n->list_lock);
>  	fixup_objfreelist_debug(cachep, &list);
>  
>  	return obj;
> @@ -2925,7 +2925,7 @@ static void *cache_alloc_refill(struct kmem_cache *cachep, gfp_t flags)
>  	if (!n->free_objects && (!shared || !shared->avail))
>  		goto direct_grow;
>  
> -	spin_lock(&n->list_lock);
> +	raw_spin_lock(&n->list_lock);
>  	shared = READ_ONCE(n->shared);
>  
>  	/* See if we can refill from the shared array */
> @@ -2949,7 +2949,7 @@ static void *cache_alloc_refill(struct kmem_cache *cachep, gfp_t flags)
>  must_grow:
>  	n->free_objects -= ac->avail;
>  alloc_done:
> -	spin_unlock(&n->list_lock);
> +	raw_spin_unlock(&n->list_lock);
>  	fixup_objfreelist_debug(cachep, &list);
>  
>  direct_grow:
> @@ -3174,7 +3174,7 @@ static void *____cache_alloc_node(struct kmem_cache *cachep, gfp_t flags,
>  	BUG_ON(!n);
>  
>  	check_irq_off();
> -	spin_lock(&n->list_lock);
> +	raw_spin_lock(&n->list_lock);
>  	page = get_first_slab(n, false);
>  	if (!page)
>  		goto must_grow;
> @@ -3192,12 +3192,12 @@ static void *____cache_alloc_node(struct kmem_cache *cachep, gfp_t flags,
>  
>  	fixup_slab_list(cachep, n, page, &list);
>  
> -	spin_unlock(&n->list_lock);
> +	raw_spin_unlock(&n->list_lock);
>  	fixup_objfreelist_debug(cachep, &list);
>  	return obj;
>  
>  must_grow:
> -	spin_unlock(&n->list_lock);
> +	raw_spin_unlock(&n->list_lock);
>  	page = cache_grow_begin(cachep, gfp_exact_node(flags), nodeid);
>  	if (page) {
>  		/* This slab isn't counted yet so don't update free_objects */
> @@ -3383,7 +3383,7 @@ static void cache_flusharray(struct kmem_cache *cachep, struct array_cache *ac)
>  
>  	check_irq_off();
>  	n = get_node(cachep, node);
> -	spin_lock(&n->list_lock);
> +	raw_spin_lock(&n->list_lock);
>  	if (n->shared) {
>  		struct array_cache *shared_array = n->shared;
>  		int max = shared_array->limit - shared_array->avail;
> @@ -3412,7 +3412,7 @@ static void cache_flusharray(struct kmem_cache *cachep, struct array_cache *ac)
>  		STATS_SET_FREEABLE(cachep, i);
>  	}
>  #endif
> -	spin_unlock(&n->list_lock);
> +	raw_spin_unlock(&n->list_lock);
>  	ac->avail -= batchcount;
>  	memmove(ac->entry, &(ac->entry[batchcount]), sizeof(void *)*ac->avail);
>  	slabs_destroy(cachep, &list);
> @@ -3877,9 +3877,9 @@ static int do_tune_cpucache(struct kmem_cache *cachep, int limit,
>  
>  		node = cpu_to_mem(cpu);
>  		n = get_node(cachep, node);
> -		spin_lock_irq(&n->list_lock);
> +		raw_spin_lock_irq(&n->list_lock);
>  		free_block(cachep, ac->entry, ac->avail, node, &list);
> -		spin_unlock_irq(&n->list_lock);
> +		raw_spin_unlock_irq(&n->list_lock);
>  		slabs_destroy(cachep, &list);
>  	}
>  	free_percpu(prev);
> @@ -3974,9 +3974,9 @@ static void drain_array(struct kmem_cache *cachep, struct kmem_cache_node *n,
>  		return;
>  	}
>  
> -	spin_lock_irq(&n->list_lock);
> +	raw_spin_lock_irq(&n->list_lock);
>  	drain_array_locked(cachep, ac, node, false, &list);
> -	spin_unlock_irq(&n->list_lock);
> +	raw_spin_unlock_irq(&n->list_lock);
>  
>  	slabs_destroy(cachep, &list);
>  }
> @@ -4060,7 +4060,7 @@ void get_slabinfo(struct kmem_cache *cachep, struct slabinfo *sinfo)
>  
>  	for_each_kmem_cache_node(cachep, node, n) {
>  		check_irq_on();
> -		spin_lock_irq(&n->list_lock);
> +		raw_spin_lock_irq(&n->list_lock);
>  
>  		total_slabs += n->total_slabs;
>  		free_slabs += n->free_slabs;
> @@ -4069,7 +4069,7 @@ void get_slabinfo(struct kmem_cache *cachep, struct slabinfo *sinfo)
>  		if (n->shared)
>  			shared_avail += n->shared->avail;
>  
> -		spin_unlock_irq(&n->list_lock);
> +		raw_spin_unlock_irq(&n->list_lock);
>  	}
>  	num_objs = total_slabs * cachep->num;
>  	active_slabs = total_slabs - free_slabs;
> diff --git a/mm/slab.h b/mm/slab.h
> index b4cdf86..ecb6e89 100644
> --- a/mm/slab.h
> +++ b/mm/slab.h
> @@ -524,7 +524,7 @@ static inline void slab_post_alloc_hook(struct kmem_cache *s,
>   * The slab lists for all objects.
>   */
>  struct kmem_cache_node {
> -	spinlock_t list_lock;
> +	raw_spinlock_t list_lock;
>  
>  #ifdef CONFIG_SLAB
>  	struct list_head slabs_partial;	/* partial list first, better asm code */
> diff --git a/mm/slub.c b/mm/slub.c
> index ee51857..c2f63c3 100644
> --- a/mm/slub.c
> +++ b/mm/slub.c
> @@ -1269,7 +1269,7 @@ static noinline int free_debug_processing(
>  	unsigned long flags;
>  	int ret = 0;
>  
> -	spin_lock_irqsave(&n->list_lock, flags);
> +	raw_spin_lock_irqsave(&n->list_lock, flags);
>  	slab_lock(page);
>  
>  	if (s->flags & SLAB_CONSISTENCY_CHECKS) {
> @@ -1304,7 +1304,7 @@ static noinline int free_debug_processing(
>  			 bulk_cnt, cnt);
>  
>  	slab_unlock(page);
> -	spin_unlock_irqrestore(&n->list_lock, flags);
> +	raw_spin_unlock_irqrestore(&n->list_lock, flags);
>  	if (!ret)
>  		slab_fix(s, "Object at 0x%px not freed", object);
>  	return ret;
> @@ -2033,7 +2033,7 @@ static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n,
>  	if (!n || !n->nr_partial)
>  		return NULL;
>  
> -	spin_lock(&n->list_lock);
> +	raw_spin_lock(&n->list_lock);
>  	list_for_each_entry_safe(page, page2, &n->partial, slab_list) {
>  		void *t;
>  
> @@ -2058,7 +2058,7 @@ static void *get_partial_node(struct kmem_cache *s, struct kmem_cache_node *n,
>  			break;
>  
>  	}
> -	spin_unlock(&n->list_lock);
> +	raw_spin_unlock(&n->list_lock);
>  	return object;
>  }
>  
> @@ -2301,7 +2301,7 @@ static void deactivate_slab(struct kmem_cache *s, struct page *page,
>  			 * that acquire_slab() will see a slab page that
>  			 * is frozen
>  			 */
> -			spin_lock(&n->list_lock);
> +			raw_spin_lock(&n->list_lock);
>  		}
>  	} else {
>  		m = M_FULL;
> @@ -2312,7 +2312,7 @@ static void deactivate_slab(struct kmem_cache *s, struct page *page,
>  			 * slabs from diagnostic functions will not see
>  			 * any frozen slabs.
>  			 */
> -			spin_lock(&n->list_lock);
> +			raw_spin_lock(&n->list_lock);
>  		}
>  	}
>  
> @@ -2336,7 +2336,7 @@ static void deactivate_slab(struct kmem_cache *s, struct page *page,
>  		goto redo;
>  
>  	if (lock)
> -		spin_unlock(&n->list_lock);
> +		raw_spin_unlock(&n->list_lock);
>  
>  	if (m == M_PARTIAL)
>  		stat(s, tail);
> @@ -2375,10 +2375,10 @@ static void unfreeze_partials(struct kmem_cache *s,
>  		n2 = get_node(s, page_to_nid(page));
>  		if (n != n2) {
>  			if (n)
> -				spin_unlock(&n->list_lock);
> +				raw_spin_unlock(&n->list_lock);
>  
>  			n = n2;
> -			spin_lock(&n->list_lock);
> +			raw_spin_lock(&n->list_lock);
>  		}
>  
>  		do {
> @@ -2407,7 +2407,7 @@ static void unfreeze_partials(struct kmem_cache *s,
>  	}
>  
>  	if (n)
> -		spin_unlock(&n->list_lock);
> +		raw_spin_unlock(&n->list_lock);
>  
>  	while (discard_page) {
>  		page = discard_page;
> @@ -2574,10 +2574,10 @@ static unsigned long count_partial(struct kmem_cache_node *n,
>  	unsigned long x = 0;
>  	struct page *page;
>  
> -	spin_lock_irqsave(&n->list_lock, flags);
> +	raw_spin_lock_irqsave(&n->list_lock, flags);
>  	list_for_each_entry(page, &n->partial, slab_list)
>  		x += get_count(page);
> -	spin_unlock_irqrestore(&n->list_lock, flags);
> +	raw_spin_unlock_irqrestore(&n->list_lock, flags);
>  	return x;
>  }
>  #endif /* CONFIG_SLUB_DEBUG || CONFIG_SYSFS */
> @@ -3045,7 +3045,7 @@ static void __slab_free(struct kmem_cache *s, struct page *page,
>  
>  	do {
>  		if (unlikely(n)) {
> -			spin_unlock_irqrestore(&n->list_lock, flags);
> +			raw_spin_unlock_irqrestore(&n->list_lock, flags);
>  			n = NULL;
>  		}
>  		prior = page->freelist;
> @@ -3077,7 +3077,7 @@ static void __slab_free(struct kmem_cache *s, struct page *page,
>  				 * Otherwise the list_lock will synchronize with
>  				 * other processors updating the list of slabs.
>  				 */
> -				spin_lock_irqsave(&n->list_lock, flags);
> +				raw_spin_lock_irqsave(&n->list_lock, flags);
>  
>  			}
>  		}
> @@ -3119,7 +3119,7 @@ static void __slab_free(struct kmem_cache *s, struct page *page,
>  		add_partial(n, page, DEACTIVATE_TO_TAIL);
>  		stat(s, FREE_ADD_PARTIAL);
>  	}
> -	spin_unlock_irqrestore(&n->list_lock, flags);
> +	raw_spin_unlock_irqrestore(&n->list_lock, flags);
>  	return;
>  
>  slab_empty:
> @@ -3134,7 +3134,7 @@ static void __slab_free(struct kmem_cache *s, struct page *page,
>  		remove_full(s, n, page);
>  	}
>  
> -	spin_unlock_irqrestore(&n->list_lock, flags);
> +	raw_spin_unlock_irqrestore(&n->list_lock, flags);
>  	stat(s, FREE_SLAB);
>  	discard_slab(s, page);
>  }
> @@ -3562,7 +3562,7 @@ static void
>  init_kmem_cache_node(struct kmem_cache_node *n)
>  {
>  	n->nr_partial = 0;
> -	spin_lock_init(&n->list_lock);
> +	raw_spin_lock_init(&n->list_lock);
>  	INIT_LIST_HEAD(&n->partial);
>  #ifdef CONFIG_SLUB_DEBUG
>  	atomic_long_set(&n->nr_slabs, 0);
> @@ -3962,7 +3962,7 @@ static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n)
>  	struct page *page, *h;
>  
>  	BUG_ON(irqs_disabled());
> -	spin_lock_irq(&n->list_lock);
> +	raw_spin_lock_irq(&n->list_lock);
>  	list_for_each_entry_safe(page, h, &n->partial, slab_list) {
>  		if (!page->inuse) {
>  			remove_partial(n, page);
> @@ -3972,7 +3972,7 @@ static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n)
>  			  "Objects remaining in %s on __kmem_cache_shutdown()");
>  		}
>  	}
> -	spin_unlock_irq(&n->list_lock);
> +	raw_spin_unlock_irq(&n->list_lock);
>  
>  	list_for_each_entry_safe(page, h, &discard, slab_list)
>  		discard_slab(s, page);
> @@ -4305,7 +4305,7 @@ int __kmem_cache_shrink(struct kmem_cache *s)
>  		for (i = 0; i < SHRINK_PROMOTE_MAX; i++)
>  			INIT_LIST_HEAD(promote + i);
>  
> -		spin_lock_irqsave(&n->list_lock, flags);
> +		raw_spin_lock_irqsave(&n->list_lock, flags);
>  
>  		/*
>  		 * Build lists of slabs to discard or promote.
> @@ -4336,7 +4336,7 @@ int __kmem_cache_shrink(struct kmem_cache *s)
>  		for (i = SHRINK_PROMOTE_MAX - 1; i >= 0; i--)
>  			list_splice(promote + i, &n->partial);
>  
> -		spin_unlock_irqrestore(&n->list_lock, flags);
> +		raw_spin_unlock_irqrestore(&n->list_lock, flags);
>  
>  		/* Release empty slabs */
>  		list_for_each_entry_safe(page, t, &discard, slab_list)
> @@ -4706,7 +4706,7 @@ static int validate_slab_node(struct kmem_cache *s,
>  	struct page *page;
>  	unsigned long flags;
>  
> -	spin_lock_irqsave(&n->list_lock, flags);
> +	raw_spin_lock_irqsave(&n->list_lock, flags);
>  
>  	list_for_each_entry(page, &n->partial, slab_list) {
>  		validate_slab(s, page);
> @@ -4732,7 +4732,7 @@ static int validate_slab_node(struct kmem_cache *s,
>  	}
>  
>  out:
> -	spin_unlock_irqrestore(&n->list_lock, flags);
> +	raw_spin_unlock_irqrestore(&n->list_lock, flags);
>  	return count;
>  }
>  
> @@ -4913,12 +4913,12 @@ static int list_locations(struct kmem_cache *s, char *buf,
>  		if (!atomic_long_read(&n->nr_slabs))
>  			continue;
>  
> -		spin_lock_irqsave(&n->list_lock, flags);
> +		raw_spin_lock_irqsave(&n->list_lock, flags);
>  		list_for_each_entry(page, &n->partial, slab_list)
>  			process_slab(&t, s, page, alloc);
>  		list_for_each_entry(page, &n->full, slab_list)
>  			process_slab(&t, s, page, alloc);
> -		spin_unlock_irqrestore(&n->list_lock, flags);
> +		raw_spin_unlock_irqrestore(&n->list_lock, flags);
>  	}
>  
>  	for (i = 0; i < t.count; i++) {
>