The patch titled
lockdep: annotate SLAB code
has been removed from the -mm tree. Its filename is
lockdep-annotate-slab-code.patch
This patch was dropped because it was merged into mainline or a subsystem tree
------------------------------------------------------
Subject: lockdep: annotate SLAB code
From: Ingo Molnar <mingo@xxxxxxx>
Teach special (recursive) locking code to the lock validator. Has no effect
on non-lockdep kernels.
Fix initialize-locks-via-memcpy assumptions.
Effects on non-lockdep kernels: the subclass nesting parameter is passed into
cache_free_alien() and __cache_free(), and turns one internal
kmem_cache_free() call into an open-coded __cache_free() call.
Signed-off-by: Ingo Molnar <mingo@xxxxxxx>
Signed-off-by: Arjan van de Ven <arjan@xxxxxxxxxxxxxxx>
Cc: Pekka Enberg <penberg@xxxxxxxxxxxxxx>
Cc: Christoph Lameter <clameter@xxxxxxxxxxxx>
Cc: Manfred Spraul <manfred@xxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxx>
---
mm/slab.c | 59 ++++++++++++++++++++++++++++++++++++++++++----------
1 file changed, 48 insertions(+), 11 deletions(-)
diff -puN mm/slab.c~lockdep-annotate-slab-code mm/slab.c
--- a/mm/slab.c~lockdep-annotate-slab-code
+++ a/mm/slab.c
@@ -1021,7 +1021,8 @@ static void drain_alien_cache(struct kme
}
}
-static inline int cache_free_alien(struct kmem_cache *cachep, void *objp)
+static inline int cache_free_alien(struct kmem_cache *cachep, void *objp,
+ int nesting)
{
struct slab *slabp = virt_to_slab(objp);
int nodeid = slabp->nodeid;
@@ -1039,7 +1040,7 @@ static inline int cache_free_alien(struc
STATS_INC_NODEFREES(cachep);
if (l3->alien && l3->alien[nodeid]) {
alien = l3->alien[nodeid];
- spin_lock(&alien->lock);
+ spin_lock_nested(&alien->lock, nesting);
if (unlikely(alien->avail == alien->limit)) {
STATS_INC_ACOVERFLOW(cachep);
__drain_alien_cache(cachep, alien, nodeid);
@@ -1068,7 +1069,8 @@ static inline void free_alien_cache(stru
{
}
-static inline int cache_free_alien(struct kmem_cache *cachep, void *objp)
+static inline int cache_free_alien(struct kmem_cache *cachep, void *objp,
+ int nesting)
{
return 0;
}
@@ -1272,6 +1274,11 @@ static void init_list(struct kmem_cache
local_irq_disable();
memcpy(ptr, list, sizeof(struct kmem_list3));
+ /*
+ * Do not assume that spinlocks can be initialized via memcpy:
+ */
+ spin_lock_init(&ptr->list_lock);
+
MAKE_ALL_LISTS(cachep, ptr, nodeid);
cachep->nodelists[nodeid] = ptr;
local_irq_enable();
@@ -1398,7 +1405,7 @@ void __init kmem_cache_init(void)
}
/* 4) Replace the bootstrap head arrays */
{
- void *ptr;
+ struct array_cache *ptr;
ptr = kmalloc(sizeof(struct arraycache_init), GFP_KERNEL);
@@ -1406,6 +1413,11 @@ void __init kmem_cache_init(void)
BUG_ON(cpu_cache_get(&cache_cache) != &initarray_cache.cache);
memcpy(ptr, cpu_cache_get(&cache_cache),
sizeof(struct arraycache_init));
+ /*
+ * Do not assume that spinlocks can be initialized via memcpy:
+ */
+ spin_lock_init(&ptr->lock);
+
cache_cache.array[smp_processor_id()] = ptr;
local_irq_enable();
@@ -1416,6 +1428,11 @@ void __init kmem_cache_init(void)
!= &initarray_generic.cache);
memcpy(ptr, cpu_cache_get(malloc_sizes[INDEX_AC].cs_cachep),
sizeof(struct arraycache_init));
+ /*
+ * Do not assume that spinlocks can be initialized via memcpy:
+ */
+ spin_lock_init(&ptr->lock);
+
malloc_sizes[INDEX_AC].cs_cachep->array[smp_processor_id()] =
ptr;
local_irq_enable();
@@ -1743,6 +1760,8 @@ static void slab_destroy_objs(struct kme
}
#endif
+static void __cache_free(struct kmem_cache *cachep, void *objp, int nesting);
+
/**
* slab_destroy - destroy and release all objects in a slab
* @cachep: cache pointer being destroyed
@@ -1766,8 +1785,17 @@ static void slab_destroy(struct kmem_cac
call_rcu(&slab_rcu->head, kmem_rcu_free);
} else {
kmem_freepages(cachep, addr);
- if (OFF_SLAB(cachep))
- kmem_cache_free(cachep->slabp_cache, slabp);
+ if (OFF_SLAB(cachep)) {
+ unsigned long flags;
+
+ /*
+ * lockdep: we may nest inside an already held
+ * ac->lock, so pass in a nesting flag:
+ */
+ local_irq_save(flags);
+ __cache_free(cachep->slabp_cache, slabp, 1);
+ local_irq_restore(flags);
+ }
}
}
@@ -3072,7 +3100,16 @@ static void free_block(struct kmem_cache
if (slabp->inuse == 0) {
if (l3->free_objects > l3->free_limit) {
l3->free_objects -= cachep->num;
+ /*
+ * It is safe to drop the lock. The slab is
+ * no longer linked to the cache. cachep
+ * cannot disappear - we are using it and
+ * all destruction of caches must be
+ * serialized properly by the user.
+ */
+ spin_unlock(&l3->list_lock);
slab_destroy(cachep, slabp);
+ spin_lock(&l3->list_lock);
} else {
list_add(&slabp->list, &l3->slabs_free);
}
@@ -3098,7 +3135,7 @@ static void cache_flusharray(struct kmem
#endif
check_irq_off();
l3 = cachep->nodelists[node];
- spin_lock(&l3->list_lock);
+ spin_lock_nested(&l3->list_lock, SINGLE_DEPTH_NESTING);
if (l3->shared) {
struct array_cache *shared_array = l3->shared;
int max = shared_array->limit - shared_array->avail;
@@ -3141,14 +3178,14 @@ free_done:
* Release an obj back to its cache. If the obj has a constructed state, it must
* be in this state _before_ it is released. Called with disabled ints.
*/
-static inline void __cache_free(struct kmem_cache *cachep, void *objp)
+static void __cache_free(struct kmem_cache *cachep, void *objp, int nesting)
{
struct array_cache *ac = cpu_cache_get(cachep);
check_irq_off();
objp = cache_free_debugcheck(cachep, objp, __builtin_return_address(0));
- if (cache_free_alien(cachep, objp))
+ if (cache_free_alien(cachep, objp, nesting))
return;
if (likely(ac->avail < ac->limit)) {
@@ -3387,7 +3424,7 @@ void kmem_cache_free(struct kmem_cache *
BUG_ON(virt_to_cache(objp) != cachep);
local_irq_save(flags);
- __cache_free(cachep, objp);
+ __cache_free(cachep, objp, 0);
local_irq_restore(flags);
}
EXPORT_SYMBOL(kmem_cache_free);
@@ -3412,7 +3449,7 @@ void kfree(const void *objp)
kfree_debugcheck(objp);
c = virt_to_cache(objp);
debug_check_no_locks_freed(objp, obj_size(c));
- __cache_free(c, (void *)objp);
+ __cache_free(c, (void *)objp, 0);
local_irq_restore(flags);
}
EXPORT_SYMBOL(kfree);
_
Patches currently in -mm which might be from mingo@xxxxxxx are
origin.patch
disable-debugging-version-of-write_lock.patch
lock-validator-fix-ns83820c-irq-flags-bug.patch
revert-gregkh-pci-pci-test-that-drivers-properly-call-pci_set_master.patch
my-name-is-ingo-molnar-you-killed-my-make-allyesconfig-prepare-to-die.patch
sched-fix-bug-in-__migrate_task.patch
small-kernel-schedc-cleanup.patch
x86-re-enable-generic-numa.patch
sched-add-above-background-load-function.patch
mm-implement-swap-prefetching.patch
sched-cleanup-remove-task_t-convert-to-struct-task_struct-prefetch.patch
genirq-convert-the-x86_64-architecture-to-irq-chips.patch
genirq-convert-the-i386-architecture-to-irq-chips.patch
genirq-irq-convert-the-move_irq-flag-from-a-32bit-word-to-a-single-bit.patch
genirq-irq-add-moved_masked_irq.patch
genirq-x86_64-irq-reenable-migrating-irqs-to-other-cpus.patch
genirq-msi-simplify-msi-enable-and-disable.patch
genirq-msi-make-the-msi-boolean-tests-return-either-0-or-1.patch
genirq-msi-implement-helper-functions-read_msi_msg-and-write_msi_msg.patch
genirq-msi-refactor-the-msi_ops.patch
genirq-msi-simplify-the-msi-irq-limit-policy.patch
genirq-irq-add-a-dynamic-irq-creation-api.patch
genirq-ia64-irq-dynamic-irq-support.patch
genirq-i386-irq-dynamic-irq-support.patch
genirq-x86_64-irq-dynamic-irq-support.patch
genirq-msi-make-the-msi-code-irq-based-and-not-vector-based.patch
genirq-x86_64-irq-move-msi-message-composition-into-io_apicc.patch
genirq-i386-irq-move-msi-message-composition-into-io_apicc.patch
genirq-msi-only-build-msi-apicc-on-ia64.patch
genirq-x86_64-irq-remove-the-msi-assumption-that-irq-==-vector.patch
genirq-i386-irq-remove-the-msi-assumption-that-irq-==-vector.patch
genirq-irq-remove-msi-hacks.patch
genirq-irq-generalize-the-check-for-hardirq_bits.patch
genirq-x86_64-irq-make-the-external-irq-handlers-report-their-vector-not-the-irq-number.patch
genirq-x86_64-irq-make-vector_irq-per-cpu.patch
genirq-x86_64-irq-kill-gsi_irq_sharing.patch
genirq-x86_64-irq-kill-irq-compression.patch
detect-atomic-counter-underflows.patch
debug-shared-irqs.patch
make-frame_pointer-default=y.patch
mutex-subsystem-synchro-test-module.patch
vdso-print-fatal-signals.patch
vdso-improve-print_fatal_signals-support-by-adding-memory-maps.patch
-
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
