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-rw-r--r--lib/Kconfig.debug21
-rw-r--r--lib/Makefile2
-rw-r--r--lib/atomic64.c4
-rw-r--r--lib/atomic64_test.c164
-rw-r--r--lib/btree.c3
-rw-r--r--lib/debugobjects.c63
-rw-r--r--lib/rwsem.c5
7 files changed, 251 insertions, 11 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 935248bdbc47..d85be90d5888 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -512,6 +512,18 @@ config PROVE_RCU
Say N if you are unsure.
+config PROVE_RCU_REPEATEDLY
+ bool "RCU debugging: don't disable PROVE_RCU on first splat"
+ depends on PROVE_RCU
+ default n
+ help
+ By itself, PROVE_RCU will disable checking upon issuing the
+ first warning (or "splat"). This feature prevents such
+ disabling, allowing multiple RCU-lockdep warnings to be printed
+ on a single reboot.
+
+ Say N if you are unsure.
+
config LOCKDEP
bool
depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT
@@ -793,7 +805,7 @@ config RCU_CPU_STALL_DETECTOR
config RCU_CPU_STALL_VERBOSE
bool "Print additional per-task information for RCU_CPU_STALL_DETECTOR"
depends on RCU_CPU_STALL_DETECTOR && TREE_PREEMPT_RCU
- default n
+ default y
help
This option causes RCU to printk detailed per-task information
for any tasks that are stalling the current RCU grace period.
@@ -1086,6 +1098,13 @@ config DMA_API_DEBUG
This option causes a performance degredation. Use only if you want
to debug device drivers. If unsure, say N.
+config ATOMIC64_SELFTEST
+ bool "Perform an atomic64_t self-test at boot"
+ help
+ Enable this option to test the atomic64_t functions at boot.
+
+ If unsure, say N.
+
source "samples/Kconfig"
source "lib/Kconfig.kgdb"
diff --git a/lib/Makefile b/lib/Makefile
index 0d4015205c64..af759f39d4ae 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -101,6 +101,8 @@ obj-$(CONFIG_GENERIC_CSUM) += checksum.o
obj-$(CONFIG_GENERIC_ATOMIC64) += atomic64.o
+obj-$(CONFIG_ATOMIC64_SELFTEST) += atomic64_test.o
+
hostprogs-y := gen_crc32table
clean-files := crc32table.h
diff --git a/lib/atomic64.c b/lib/atomic64.c
index 8bee16ec7524..a21c12bc727c 100644
--- a/lib/atomic64.c
+++ b/lib/atomic64.c
@@ -162,12 +162,12 @@ int atomic64_add_unless(atomic64_t *v, long long a, long long u)
{
unsigned long flags;
spinlock_t *lock = lock_addr(v);
- int ret = 1;
+ int ret = 0;
spin_lock_irqsave(lock, flags);
if (v->counter != u) {
v->counter += a;
- ret = 0;
+ ret = 1;
}
spin_unlock_irqrestore(lock, flags);
return ret;
diff --git a/lib/atomic64_test.c b/lib/atomic64_test.c
new file mode 100644
index 000000000000..65e482caf5e9
--- /dev/null
+++ b/lib/atomic64_test.c
@@ -0,0 +1,164 @@
+/*
+ * Testsuite for atomic64_t functions
+ *
+ * Copyright © 2010 Luca Barbieri
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+#include <linux/init.h>
+#include <asm/atomic.h>
+
+#define INIT(c) do { atomic64_set(&v, c); r = c; } while (0)
+static __init int test_atomic64(void)
+{
+ long long v0 = 0xaaa31337c001d00dLL;
+ long long v1 = 0xdeadbeefdeafcafeLL;
+ long long v2 = 0xfaceabadf00df001LL;
+ long long onestwos = 0x1111111122222222LL;
+ long long one = 1LL;
+
+ atomic64_t v = ATOMIC64_INIT(v0);
+ long long r = v0;
+ BUG_ON(v.counter != r);
+
+ atomic64_set(&v, v1);
+ r = v1;
+ BUG_ON(v.counter != r);
+ BUG_ON(atomic64_read(&v) != r);
+
+ INIT(v0);
+ atomic64_add(onestwos, &v);
+ r += onestwos;
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ atomic64_add(-one, &v);
+ r += -one;
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ r += onestwos;
+ BUG_ON(atomic64_add_return(onestwos, &v) != r);
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ r += -one;
+ BUG_ON(atomic64_add_return(-one, &v) != r);
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ atomic64_sub(onestwos, &v);
+ r -= onestwos;
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ atomic64_sub(-one, &v);
+ r -= -one;
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ r -= onestwos;
+ BUG_ON(atomic64_sub_return(onestwos, &v) != r);
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ r -= -one;
+ BUG_ON(atomic64_sub_return(-one, &v) != r);
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ atomic64_inc(&v);
+ r += one;
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ r += one;
+ BUG_ON(atomic64_inc_return(&v) != r);
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ atomic64_dec(&v);
+ r -= one;
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ r -= one;
+ BUG_ON(atomic64_dec_return(&v) != r);
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ BUG_ON(atomic64_xchg(&v, v1) != v0);
+ r = v1;
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ BUG_ON(atomic64_cmpxchg(&v, v0, v1) != v0);
+ r = v1;
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ BUG_ON(atomic64_cmpxchg(&v, v2, v1) != v0);
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ BUG_ON(atomic64_add_unless(&v, one, v0));
+ BUG_ON(v.counter != r);
+
+ INIT(v0);
+ BUG_ON(!atomic64_add_unless(&v, one, v1));
+ r += one;
+ BUG_ON(v.counter != r);
+
+#if defined(CONFIG_X86) || defined(CONFIG_MIPS) || defined(CONFIG_PPC) || defined(_ASM_GENERIC_ATOMIC64_H)
+ INIT(onestwos);
+ BUG_ON(atomic64_dec_if_positive(&v) != (onestwos - 1));
+ r -= one;
+ BUG_ON(v.counter != r);
+
+ INIT(0);
+ BUG_ON(atomic64_dec_if_positive(&v) != -one);
+ BUG_ON(v.counter != r);
+
+ INIT(-one);
+ BUG_ON(atomic64_dec_if_positive(&v) != (-one - one));
+ BUG_ON(v.counter != r);
+#else
+#warning Please implement atomic64_dec_if_positive for your architecture, and add it to the IF above
+#endif
+
+ INIT(onestwos);
+ BUG_ON(!atomic64_inc_not_zero(&v));
+ r += one;
+ BUG_ON(v.counter != r);
+
+ INIT(0);
+ BUG_ON(atomic64_inc_not_zero(&v));
+ BUG_ON(v.counter != r);
+
+ INIT(-one);
+ BUG_ON(!atomic64_inc_not_zero(&v));
+ r += one;
+ BUG_ON(v.counter != r);
+
+#ifdef CONFIG_X86
+ printk(KERN_INFO "atomic64 test passed for %s platform %s CX8 and %s SSE\n",
+#ifdef CONFIG_X86_64
+ "x86-64",
+#elif defined(CONFIG_X86_CMPXCHG64)
+ "i586+",
+#else
+ "i386+",
+#endif
+ boot_cpu_has(X86_FEATURE_CX8) ? "with" : "without",
+ boot_cpu_has(X86_FEATURE_XMM) ? "with" : "without");
+#else
+ printk(KERN_INFO "atomic64 test passed\n");
+#endif
+
+ return 0;
+}
+
+core_initcall(test_atomic64);
diff --git a/lib/btree.c b/lib/btree.c
index 41859a820218..c9c6f0351526 100644
--- a/lib/btree.c
+++ b/lib/btree.c
@@ -95,7 +95,8 @@ static unsigned long *btree_node_alloc(struct btree_head *head, gfp_t gfp)
unsigned long *node;
node = mempool_alloc(head->mempool, gfp);
- memset(node, 0, NODESIZE);
+ if (likely(node))
+ memset(node, 0, NODESIZE);
return node;
}
diff --git a/lib/debugobjects.c b/lib/debugobjects.c
index b862b30369ff..deebcc57d4e6 100644
--- a/lib/debugobjects.c
+++ b/lib/debugobjects.c
@@ -141,6 +141,7 @@ alloc_object(void *addr, struct debug_bucket *b, struct debug_obj_descr *descr)
obj->object = addr;
obj->descr = descr;
obj->state = ODEBUG_STATE_NONE;
+ obj->astate = 0;
hlist_del(&obj->node);
hlist_add_head(&obj->node, &b->list);
@@ -252,8 +253,10 @@ static void debug_print_object(struct debug_obj *obj, char *msg)
if (limit < 5 && obj->descr != descr_test) {
limit++;
- WARN(1, KERN_ERR "ODEBUG: %s %s object type: %s\n", msg,
- obj_states[obj->state], obj->descr->name);
+ WARN(1, KERN_ERR "ODEBUG: %s %s (active state %u) "
+ "object type: %s\n",
+ msg, obj_states[obj->state], obj->astate,
+ obj->descr->name);
}
debug_objects_warnings++;
}
@@ -447,7 +450,10 @@ void debug_object_deactivate(void *addr, struct debug_obj_descr *descr)
case ODEBUG_STATE_INIT:
case ODEBUG_STATE_INACTIVE:
case ODEBUG_STATE_ACTIVE:
- obj->state = ODEBUG_STATE_INACTIVE;
+ if (!obj->astate)
+ obj->state = ODEBUG_STATE_INACTIVE;
+ else
+ debug_print_object(obj, "deactivate");
break;
case ODEBUG_STATE_DESTROYED:
@@ -553,6 +559,53 @@ out_unlock:
raw_spin_unlock_irqrestore(&db->lock, flags);
}
+/**
+ * debug_object_active_state - debug checks object usage state machine
+ * @addr: address of the object
+ * @descr: pointer to an object specific debug description structure
+ * @expect: expected state
+ * @next: state to move to if expected state is found
+ */
+void
+debug_object_active_state(void *addr, struct debug_obj_descr *descr,
+ unsigned int expect, unsigned int next)
+{
+ struct debug_bucket *db;
+ struct debug_obj *obj;
+ unsigned long flags;
+
+ if (!debug_objects_enabled)
+ return;
+
+ db = get_bucket((unsigned long) addr);
+
+ raw_spin_lock_irqsave(&db->lock, flags);
+
+ obj = lookup_object(addr, db);
+ if (obj) {
+ switch (obj->state) {
+ case ODEBUG_STATE_ACTIVE:
+ if (obj->astate == expect)
+ obj->astate = next;
+ else
+ debug_print_object(obj, "active_state");
+ break;
+
+ default:
+ debug_print_object(obj, "active_state");
+ break;
+ }
+ } else {
+ struct debug_obj o = { .object = addr,
+ .state = ODEBUG_STATE_NOTAVAILABLE,
+ .descr = descr };
+
+ debug_print_object(&o, "active_state");
+ }
+
+ raw_spin_unlock_irqrestore(&db->lock, flags);
+}
+
#ifdef CONFIG_DEBUG_OBJECTS_FREE
static void __debug_check_no_obj_freed(const void *address, unsigned long size)
{
@@ -774,7 +827,7 @@ static int __init fixup_free(void *addr, enum debug_obj_state state)
}
}
-static int
+static int __init
check_results(void *addr, enum debug_obj_state state, int fixups, int warnings)
{
struct debug_bucket *db;
@@ -917,7 +970,7 @@ void __init debug_objects_early_init(void)
/*
* Convert the statically allocated objects to dynamic ones:
*/
-static int debug_objects_replace_static_objects(void)
+static int __init debug_objects_replace_static_objects(void)
{
struct debug_bucket *db = obj_hash;
struct hlist_node *node, *tmp;
diff --git a/lib/rwsem.c b/lib/rwsem.c
index 3e3365e5665e..ceba8e28807a 100644
--- a/lib/rwsem.c
+++ b/lib/rwsem.c
@@ -136,9 +136,10 @@ __rwsem_do_wake(struct rw_semaphore *sem, int downgrading)
out:
return sem;
- /* undo the change to count, but check for a transition 1->0 */
+ /* undo the change to the active count, but check for a transition
+ * 1->0 */
undo:
- if (rwsem_atomic_update(-RWSEM_ACTIVE_BIAS, sem) != 0)
+ if (rwsem_atomic_update(-RWSEM_ACTIVE_BIAS, sem) & RWSEM_ACTIVE_MASK)
goto out;
goto try_again;
}