mm, slub: make slab_lock() disable irqs with PREEMPT_RT

[platform/kernel/linux-starfive.git] / mm / slub.c

diff --git a/mm/slub.c b/mm/slub.c
index 76e56ce..a04c36e 100644 (file)
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -359,25 +359,44 @@ static inline unsigned int oo_objects(struct kmem_cache_order_objects x)
 /*
  * Per slab locking using the pagelock
  */
-static __always_inline void slab_lock(struct page *page)
+static __always_inline void __slab_lock(struct page *page)
 {
        VM_BUG_ON_PAGE(PageTail(page), page);
        bit_spin_lock(PG_locked, &page->flags);
 }
 
-static __always_inline void slab_unlock(struct page *page)
+static __always_inline void __slab_unlock(struct page *page)
 {
        VM_BUG_ON_PAGE(PageTail(page), page);
        __bit_spin_unlock(PG_locked, &page->flags);
 }
 
-/* Interrupts must be disabled (for the fallback code to work right) */
+static __always_inline void slab_lock(struct page *page, unsigned long *flags)
+{
+       if (IS_ENABLED(CONFIG_PREEMPT_RT))
+               local_irq_save(*flags);
+       __slab_lock(page);
+}
+
+static __always_inline void slab_unlock(struct page *page, unsigned long *flags)
+{
+       __slab_unlock(page);
+       if (IS_ENABLED(CONFIG_PREEMPT_RT))
+               local_irq_restore(*flags);
+}
+
+/*
+ * Interrupts must be disabled (for the fallback code to work right), typically
+ * by an _irqsave() lock variant. Except on PREEMPT_RT where locks are different
+ * so we disable interrupts as part of slab_[un]lock().
+ */
 static inline bool __cmpxchg_double_slab(struct kmem_cache *s, struct page *page,
                void *freelist_old, unsigned long counters_old,
                void *freelist_new, unsigned long counters_new,
                const char *n)
 {
-       VM_BUG_ON(!irqs_disabled());
+       if (!IS_ENABLED(CONFIG_PREEMPT_RT))
+               lockdep_assert_irqs_disabled();
 #if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && \
     defined(CONFIG_HAVE_ALIGNED_STRUCT_PAGE)
        if (s->flags & __CMPXCHG_DOUBLE) {
@@ -388,15 +407,18 @@ static inline bool __cmpxchg_double_slab(struct kmem_cache *s, struct page *page
        } else
 #endif
        {
-               slab_lock(page);
+               /* init to 0 to prevent spurious warnings */
+               unsigned long flags = 0;
+
+               slab_lock(page, &flags);
                if (page->freelist == freelist_old &&
                                        page->counters == counters_old) {
                        page->freelist = freelist_new;
                        page->counters = counters_new;
-                       slab_unlock(page);
+                       slab_unlock(page, &flags);
                        return true;
                }
-               slab_unlock(page);
+               slab_unlock(page, &flags);
        }
 
        cpu_relax();
@@ -427,16 +449,16 @@ static inline bool cmpxchg_double_slab(struct kmem_cache *s, struct page *page,
                unsigned long flags;
 
                local_irq_save(flags);
-               slab_lock(page);
+               __slab_lock(page);
                if (page->freelist == freelist_old &&
                                        page->counters == counters_old) {
                        page->freelist = freelist_new;
                        page->counters = counters_new;
-                       slab_unlock(page);
+                       __slab_unlock(page);
                        local_irq_restore(flags);
                        return true;
                }
-               slab_unlock(page);
+               __slab_unlock(page);
                local_irq_restore(flags);
        }
 
@@ -1269,11 +1291,11 @@ static noinline int free_debug_processing(
        struct kmem_cache_node *n = get_node(s, page_to_nid(page));
        void *object = head;
        int cnt = 0;
-       unsigned long flags;
+       unsigned long flags, flags2;
        int ret = 0;
 
        spin_lock_irqsave(&n->list_lock, flags);
-       slab_lock(page);
+       slab_lock(page, &flags2);
 
        if (s->flags & SLAB_CONSISTENCY_CHECKS) {
                if (!check_slab(s, page))
@@ -1306,7 +1328,7 @@ out:
                slab_err(s, page, "Bulk freelist count(%d) invalid(%d)\n",
                         bulk_cnt, cnt);
 
-       slab_unlock(page);
+       slab_unlock(page, &flags2);
        spin_unlock_irqrestore(&n->list_lock, flags);
        if (!ret)
                slab_fix(s, "Object at 0x%p not freed", object);
@@ -4087,11 +4109,12 @@ static void list_slab_objects(struct kmem_cache *s, struct page *page,
 {
 #ifdef CONFIG_SLUB_DEBUG
        void *addr = page_address(page);
+       unsigned long flags;
        unsigned long *map;
        void *p;
 
        slab_err(s, page, text, s->name);
-       slab_lock(page);
+       slab_lock(page, &flags);
 
        map = get_map(s, page);
        for_each_object(p, s, addr, page->objects) {
@@ -4102,7 +4125,7 @@ static void list_slab_objects(struct kmem_cache *s, struct page *page,
                }
        }
        put_map(map);
-       slab_unlock(page);
+       slab_unlock(page, &flags);
 #endif
 }
 
@@ -4834,8 +4857,9 @@ static void validate_slab(struct kmem_cache *s, struct page *page,
 {
        void *p;
        void *addr = page_address(page);
+       unsigned long flags;
 
-       slab_lock(page);
+       slab_lock(page, &flags);
 
        if (!check_slab(s, page) || !on_freelist(s, page, NULL))
                goto unlock;
@@ -4850,7 +4874,7 @@ static void validate_slab(struct kmem_cache *s, struct page *page,
                        break;
        }
 unlock:
-       slab_unlock(page);
+       slab_unlock(page, &flags);
 }
 
 static int validate_slab_node(struct kmem_cache *s,