These changes are the raw update to linux-4.4.6-rt14. Kernel sources

are taken from kernel.org, and rt patch from the rt wiki download page.

During the rebasing, the following patch collided:

Force tick interrupt and get rid of softirq magic(I70131fb85).

Collisions have been removed because its logic was found on the
source already.

Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769
Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>

1 files changed, 185 insertions, 76 deletions

diff --git a/kernel/mm/slab_common.c b/kernel/mm/slab_common.c
index 999bb3424..3c6a86b4e 100644
--- a/kernel/mm/slab_common.c
+++ b/kernel/mm/slab_common.c
@@ -37,8 +37,7 @@ struct kmem_cache *kmem_cache;
 		SLAB_TRACE | SLAB_DESTROY_BY_RCU | SLAB_NOLEAKTRACE | \
 		SLAB_FAILSLAB)
 
-#define SLAB_MERGE_SAME (SLAB_DEBUG_FREE | SLAB_RECLAIM_ACCOUNT | \
-		SLAB_CACHE_DMA | SLAB_NOTRACK)
+#define SLAB_MERGE_SAME (SLAB_RECLAIM_ACCOUNT | SLAB_CACHE_DMA | SLAB_NOTRACK)
 
 /*
  * Merge control. If this is set then no merging of slab caches will occur.
@@ -105,6 +104,29 @@ static inline int kmem_cache_sanity_check(const char *name, size_t size)
 }
 #endif
 
+void __kmem_cache_free_bulk(struct kmem_cache *s, size_t nr, void **p)
+{
+	size_t i;
+
+	for (i = 0; i < nr; i++)
+		kmem_cache_free(s, p[i]);
+}
+
+int __kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t nr,
+								void **p)
+{
+	size_t i;
+
+	for (i = 0; i < nr; i++) {
+		void *x = p[i] = kmem_cache_alloc(s, flags);
+		if (!x) {
+			__kmem_cache_free_bulk(s, i, p);
+			return 0;
+		}
+	}
+	return i;
+}
+
 #ifdef CONFIG_MEMCG_KMEM
 void slab_init_memcg_params(struct kmem_cache *s)
 {
@@ -294,10 +316,10 @@ unsigned long calculate_alignment(unsigned long flags,
 	return ALIGN(align, sizeof(void *));
 }
 
-static struct kmem_cache *
-do_kmem_cache_create(const char *name, size_t object_size, size_t size,
-		     size_t align, unsigned long flags, void (*ctor)(void *),
-		     struct mem_cgroup *memcg, struct kmem_cache *root_cache)
+static struct kmem_cache *create_cache(const char *name,
+		size_t object_size, size_t size, size_t align,
+		unsigned long flags, void (*ctor)(void *),
+		struct mem_cgroup *memcg, struct kmem_cache *root_cache)
 {
 	struct kmem_cache *s;
 	int err;
@@ -362,7 +384,7 @@ struct kmem_cache *
 kmem_cache_create(const char *name, size_t size, size_t align,
 		  unsigned long flags, void (*ctor)(void *))
 {
-	struct kmem_cache *s;
+	struct kmem_cache *s = NULL;
 	const char *cache_name;
 	int err;
 
@@ -374,7 +396,6 @@ kmem_cache_create(const char *name, size_t size, size_t align,
 
 	err = kmem_cache_sanity_check(name, size);
 	if (err) {
-		s = NULL;	/* suppress uninit var warning */
 		goto out_unlock;
 	}
 
@@ -396,9 +417,9 @@ kmem_cache_create(const char *name, size_t size, size_t align,
 		goto out_unlock;
 	}
 
-	s = do_kmem_cache_create(cache_name, size, size,
-				 calculate_alignment(flags, align, size),
-				 flags, ctor, NULL, NULL);
+	s = create_cache(cache_name, size, size,
+			 calculate_alignment(flags, align, size),
+			 flags, ctor, NULL, NULL);
 	if (IS_ERR(s)) {
 		err = PTR_ERR(s);
 		kfree_const(cache_name);
@@ -426,29 +447,20 @@ out_unlock:
 }
 EXPORT_SYMBOL(kmem_cache_create);
 
-static int do_kmem_cache_shutdown(struct kmem_cache *s,
+static int shutdown_cache(struct kmem_cache *s,
 		struct list_head *release, bool *need_rcu_barrier)
 {
-	if (__kmem_cache_shutdown(s) != 0) {
-		printk(KERN_ERR "kmem_cache_destroy %s: "
-		       "Slab cache still has objects\n", s->name);
-		dump_stack();
+	if (__kmem_cache_shutdown(s) != 0)
 		return -EBUSY;
-	}
 
 	if (s->flags & SLAB_DESTROY_BY_RCU)
 		*need_rcu_barrier = true;
 
-#ifdef CONFIG_MEMCG_KMEM
-	if (!is_root_cache(s))
-		list_del(&s->memcg_params.list);
-#endif
 	list_move(&s->list, release);
 	return 0;
 }
 
-static void do_kmem_cache_release(struct list_head *release,
-				  bool need_rcu_barrier)
+static void release_caches(struct list_head *release, bool need_rcu_barrier)
 {
 	struct kmem_cache *s, *s2;
 
@@ -478,7 +490,7 @@ void memcg_create_kmem_cache(struct mem_cgroup *memcg,
 			     struct kmem_cache *root_cache)
 {
 	static char memcg_name_buf[NAME_MAX + 1]; /* protected by slab_mutex */
-	struct cgroup_subsys_state *css = mem_cgroup_css(memcg);
+	struct cgroup_subsys_state *css = &memcg->css;
 	struct memcg_cache_array *arr;
 	struct kmem_cache *s = NULL;
 	char *cache_name;
@@ -514,10 +526,10 @@ void memcg_create_kmem_cache(struct mem_cgroup *memcg,
 	if (!cache_name)
 		goto out_unlock;
 
-	s = do_kmem_cache_create(cache_name, root_cache->object_size,
-				 root_cache->size, root_cache->align,
-				 root_cache->flags, root_cache->ctor,
-				 memcg, root_cache);
+	s = create_cache(cache_name, root_cache->object_size,
+			 root_cache->size, root_cache->align,
+			 root_cache->flags, root_cache->ctor,
+			 memcg, root_cache);
 	/*
 	 * If we could not create a memcg cache, do not complain, because
 	 * that's not critical at all as we can always proceed with the root
@@ -576,6 +588,18 @@ void memcg_deactivate_kmem_caches(struct mem_cgroup *memcg)
 	put_online_cpus();
 }
 
+static int __shutdown_memcg_cache(struct kmem_cache *s,
+		struct list_head *release, bool *need_rcu_barrier)
+{
+	BUG_ON(is_root_cache(s));
+
+	if (shutdown_cache(s, release, need_rcu_barrier))
+		return -EBUSY;
+
+	list_del(&s->memcg_params.list);
+	return 0;
+}
+
 void memcg_destroy_kmem_caches(struct mem_cgroup *memcg)
 {
 	LIST_HEAD(release);
@@ -593,14 +617,76 @@ void memcg_destroy_kmem_caches(struct mem_cgroup *memcg)
 		 * The cgroup is about to be freed and therefore has no charges
 		 * left. Hence, all its caches must be empty by now.
 		 */
-		BUG_ON(do_kmem_cache_shutdown(s, &release, &need_rcu_barrier));
+		BUG_ON(__shutdown_memcg_cache(s, &release, &need_rcu_barrier));
 	}
 	mutex_unlock(&slab_mutex);
 
 	put_online_mems();
 	put_online_cpus();
 
-	do_kmem_cache_release(&release, need_rcu_barrier);
+	release_caches(&release, need_rcu_barrier);
+}
+
+static int shutdown_memcg_caches(struct kmem_cache *s,
+		struct list_head *release, bool *need_rcu_barrier)
+{
+	struct memcg_cache_array *arr;
+	struct kmem_cache *c, *c2;
+	LIST_HEAD(busy);
+	int i;
+
+	BUG_ON(!is_root_cache(s));
+
+	/*
+	 * First, shutdown active caches, i.e. caches that belong to online
+	 * memory cgroups.
+	 */
+	arr = rcu_dereference_protected(s->memcg_params.memcg_caches,
+					lockdep_is_held(&slab_mutex));
+	for_each_memcg_cache_index(i) {
+		c = arr->entries[i];
+		if (!c)
+			continue;
+		if (__shutdown_memcg_cache(c, release, need_rcu_barrier))
+			/*
+			 * The cache still has objects. Move it to a temporary
+			 * list so as not to try to destroy it for a second
+			 * time while iterating over inactive caches below.
+			 */
+			list_move(&c->memcg_params.list, &busy);
+		else
+			/*
+			 * The cache is empty and will be destroyed soon. Clear
+			 * the pointer to it in the memcg_caches array so that
+			 * it will never be accessed even if the root cache
+			 * stays alive.
+			 */
+			arr->entries[i] = NULL;
+	}
+
+	/*
+	 * Second, shutdown all caches left from memory cgroups that are now
+	 * offline.
+	 */
+	list_for_each_entry_safe(c, c2, &s->memcg_params.list,
+				 memcg_params.list)
+		__shutdown_memcg_cache(c, release, need_rcu_barrier);
+
+	list_splice(&busy, &s->memcg_params.list);
+
+	/*
+	 * A cache being destroyed must be empty. In particular, this means
+	 * that all per memcg caches attached to it must be empty too.
+	 */
+	if (!list_empty(&s->memcg_params.list))
+		return -EBUSY;
+	return 0;
+}
+#else
+static inline int shutdown_memcg_caches(struct kmem_cache *s,
+		struct list_head *release, bool *need_rcu_barrier)
+{
+	return 0;
 }
 #endif /* CONFIG_MEMCG_KMEM */
 
@@ -613,12 +699,12 @@ void slab_kmem_cache_release(struct kmem_cache *s)
 
 void kmem_cache_destroy(struct kmem_cache *s)
 {
-	struct kmem_cache *c, *c2;
 	LIST_HEAD(release);
 	bool need_rcu_barrier = false;
-	bool busy = false;
+	int err;
 
-	BUG_ON(!is_root_cache(s));
+	if (unlikely(!s))
+		return;
 
 	get_online_cpus();
 	get_online_mems();
@@ -629,21 +715,22 @@ void kmem_cache_destroy(struct kmem_cache *s)
 	if (s->refcount)
 		goto out_unlock;
 
-	for_each_memcg_cache_safe(c, c2, s) {
-		if (do_kmem_cache_shutdown(c, &release, &need_rcu_barrier))
-			busy = true;
-	}
-
-	if (!busy)
-		do_kmem_cache_shutdown(s, &release, &need_rcu_barrier);
+	err = shutdown_memcg_caches(s, &release, &need_rcu_barrier);
+	if (!err)
+		err = shutdown_cache(s, &release, &need_rcu_barrier);
 
+	if (err) {
+		pr_err("kmem_cache_destroy %s: "
+		       "Slab cache still has objects\n", s->name);
+		dump_stack();
+	}
 out_unlock:
 	mutex_unlock(&slab_mutex);
 
 	put_online_mems();
 	put_online_cpus();
 
-	do_kmem_cache_release(&release, need_rcu_barrier);
+	release_caches(&release, need_rcu_barrier);
 }
 EXPORT_SYMBOL(kmem_cache_destroy);
 
@@ -667,7 +754,7 @@ int kmem_cache_shrink(struct kmem_cache *cachep)
 }
 EXPORT_SYMBOL(kmem_cache_shrink);
 
-int slab_is_available(void)
+bool slab_is_available(void)
 {
 	return slab_state >= UP;
 }
@@ -784,25 +871,45 @@ struct kmem_cache *kmalloc_slab(size_t size, gfp_t flags)
 }
 
 /*
- * Create the kmalloc array. Some of the regular kmalloc arrays
- * may already have been created because they were needed to
- * enable allocations for slab creation.
+ * kmalloc_info[] is to make slub_debug=,kmalloc-xx option work at boot time.
+ * kmalloc_index() supports up to 2^26=64MB, so the final entry of the table is
+ * kmalloc-67108864.
  */
-void __init create_kmalloc_caches(unsigned long flags)
+static struct {
+	const char *name;
+	unsigned long size;
+} const kmalloc_info[] __initconst = {
+	{NULL,                      0},		{"kmalloc-96",             96},
+	{"kmalloc-192",           192},		{"kmalloc-8",               8},
+	{"kmalloc-16",             16},		{"kmalloc-32",             32},
+	{"kmalloc-64",             64},		{"kmalloc-128",           128},
+	{"kmalloc-256",           256},		{"kmalloc-512",           512},
+	{"kmalloc-1024",         1024},		{"kmalloc-2048",         2048},
+	{"kmalloc-4096",         4096},		{"kmalloc-8192",         8192},
+	{"kmalloc-16384",       16384},		{"kmalloc-32768",       32768},
+	{"kmalloc-65536",       65536},		{"kmalloc-131072",     131072},
+	{"kmalloc-262144",     262144},		{"kmalloc-524288",     524288},
+	{"kmalloc-1048576",   1048576},		{"kmalloc-2097152",   2097152},
+	{"kmalloc-4194304",   4194304},		{"kmalloc-8388608",   8388608},
+	{"kmalloc-16777216", 16777216},		{"kmalloc-33554432", 33554432},
+	{"kmalloc-67108864", 67108864}
+};
+
+/*
+ * Patch up the size_index table if we have strange large alignment
+ * requirements for the kmalloc array. This is only the case for
+ * MIPS it seems. The standard arches will not generate any code here.
+ *
+ * Largest permitted alignment is 256 bytes due to the way we
+ * handle the index determination for the smaller caches.
+ *
+ * Make sure that nothing crazy happens if someone starts tinkering
+ * around with ARCH_KMALLOC_MINALIGN
+ */
+void __init setup_kmalloc_cache_index_table(void)
 {
 	int i;
 
-	/*
-	 * Patch up the size_index table if we have strange large alignment
-	 * requirements for the kmalloc array. This is only the case for
-	 * MIPS it seems. The standard arches will not generate any code here.
-	 *
-	 * Largest permitted alignment is 256 bytes due to the way we
-	 * handle the index determination for the smaller caches.
-	 *
-	 * Make sure that nothing crazy happens if someone starts tinkering
-	 * around with ARCH_KMALLOC_MINALIGN
-	 */
 	BUILD_BUG_ON(KMALLOC_MIN_SIZE > 256 ||
 		(KMALLOC_MIN_SIZE & (KMALLOC_MIN_SIZE - 1)));
 
@@ -833,11 +940,26 @@ void __init create_kmalloc_caches(unsigned long flags)
 		for (i = 128 + 8; i <= 192; i += 8)
 			size_index[size_index_elem(i)] = 8;
 	}
+}
+
+static void __init new_kmalloc_cache(int idx, unsigned long flags)
+{
+	kmalloc_caches[idx] = create_kmalloc_cache(kmalloc_info[idx].name,
+					kmalloc_info[idx].size, flags);
+}
+
+/*
+ * Create the kmalloc array. Some of the regular kmalloc arrays
+ * may already have been created because they were needed to
+ * enable allocations for slab creation.
+ */
+void __init create_kmalloc_caches(unsigned long flags)
+{
+	int i;
+
 	for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++) {
-		if (!kmalloc_caches[i]) {
-			kmalloc_caches[i] = create_kmalloc_cache(NULL,
-							1 << i, flags);
-		}
+		if (!kmalloc_caches[i])
+			new_kmalloc_cache(i, flags);
 
 		/*
 		 * Caches that are not of the two-to-the-power-of size.
@@ -845,27 +967,14 @@ void __init create_kmalloc_caches(unsigned long flags)
 		 * earlier power of two caches
 		 */
 		if (KMALLOC_MIN_SIZE <= 32 && !kmalloc_caches[1] && i == 6)
-			kmalloc_caches[1] = create_kmalloc_cache(NULL, 96, flags);
-
+			new_kmalloc_cache(1, flags);
 		if (KMALLOC_MIN_SIZE <= 64 && !kmalloc_caches[2] && i == 7)
-			kmalloc_caches[2] = create_kmalloc_cache(NULL, 192, flags);
+			new_kmalloc_cache(2, flags);
 	}
 
 	/* Kmalloc array is now usable */
 	slab_state = UP;
 
-	for (i = 0; i <= KMALLOC_SHIFT_HIGH; i++) {
-		struct kmem_cache *s = kmalloc_caches[i];
-		char *n;
-
-		if (s) {
-			n = kasprintf(GFP_NOWAIT, "kmalloc-%d", kmalloc_size(i));
-
-			BUG_ON(!n);
-			s->name = n;
-		}
-	}
-
 #ifdef CONFIG_ZONE_DMA
 	for (i = 0; i <= KMALLOC_SHIFT_HIGH; i++) {
 		struct kmem_cache *s = kmalloc_caches[i];