BUG/MINOR: pools/threads: don't ignore DEBUG_UAF on double-word CAS capable archs
Since commit cf975d4 ("MINOR: pools/threads: Implement lockless memory
pools."), we support lockless pools. However the parts dedicated to
detecting use-after-free are not present in this part, making DEBUG_UAF
useless in this situation.
The present patch sets a new define CONFIG_HAP_LOCKLESS_POOLS when such
a compatible architecture is detected, and when pool debugging is not
requested, then makes use of this everywhere in pools and buffers
functions. This way enabling DEBUG_UAF will automatically disable the
lockless version.
No backport is needed as this is purely 1.9-dev.
diff --git a/include/common/buffer.h b/include/common/buffer.h
index 20070cc..c920298 100644
--- a/include/common/buffer.h
+++ b/include/common/buffer.h
@@ -735,7 +735,7 @@
return *buf;
*buf = &buf_wanted;
-#ifndef HA_HAVE_CAS_DW
+#ifndef CONFIG_HAP_LOCKLESS_POOLS
HA_SPIN_LOCK(POOL_LOCK, &pool_head_buffer->lock);
#endif
@@ -743,7 +743,7 @@
if ((pool_head_buffer->allocated - pool_head_buffer->used) > margin) {
b = __pool_get_first(pool_head_buffer);
if (likely(b)) {
-#ifndef HA_HAVE_CAS_DW
+#ifndef CONFIG_HAP_LOCKLESS_POOLS
HA_SPIN_UNLOCK(POOL_LOCK, &pool_head_buffer->lock);
#endif
b->size = pool_head_buffer->size - sizeof(struct buffer);
@@ -756,7 +756,7 @@
/* slow path, uses malloc() */
b = __pool_refill_alloc(pool_head_buffer, margin);
-#ifndef HA_HAVE_CAS_DW
+#ifndef CONFIG_HAP_LOCKLESS_POOLS
HA_SPIN_UNLOCK(POOL_LOCK, &pool_head_buffer->lock);
#endif
diff --git a/include/common/config.h b/include/common/config.h
index f06ba3b..acd6b20 100644
--- a/include/common/config.h
+++ b/include/common/config.h
@@ -47,6 +47,13 @@
#define THREAD_LOCAL
#endif
+/* On architectures supporting threads and double-word CAS, we can implement
+ * lock-less memory pools. This isn't supported for debugging modes however.
+ */
+#if !defined(DEBUG_NO_LOCKLESS_POOLS) && defined(USE_THREAD) && defined(HA_HAVE_CAS_DW) && !defined(DEBUG_UAF)
+#define CONFIG_HAP_LOCKLESS_POOLS
+#endif
+
/* CONFIG_HAP_INLINE_FD_SET
* This makes use of inline FD_* macros instead of calling equivalent
* functions. Benchmarks on a Pentium-M show that using functions is
diff --git a/include/common/memory.h b/include/common/memory.h
index 52ca88e..bf77f95 100644
--- a/include/common/memory.h
+++ b/include/common/memory.h
@@ -48,7 +48,7 @@
#define POOL_LINK(pool, item) ((void **)(item))
#endif
-#ifdef HA_HAVE_CAS_DW
+#ifdef CONFIG_HAP_LOCKLESS_POOLS
struct pool_free_list {
void **free_list;
uintptr_t seq;
@@ -57,7 +57,7 @@
struct pool_head {
void **free_list;
-#ifdef HA_HAVE_CAS_DW
+#ifdef CONFIG_HAP_LOCKLESS_POOLS
uintptr_t seq;
#else
__decl_hathreads(HA_SPINLOCK_T lock); /* the spin lock */
@@ -123,7 +123,7 @@
*/
void *pool_destroy(struct pool_head *pool);
-#ifdef HA_HAVE_CAS_DW
+#ifdef CONFIG_HAP_LOCKLESS_POOLS
/*
* Returns a pointer to type <type> taken from the pool <pool_type> if
* available, otherwise returns NULL. No malloc() is attempted, and poisonning
@@ -226,7 +226,7 @@
}
}
-#else
+#else /* CONFIG_HAP_LOCKLESS_POOLS */
/*
* Returns a pointer to type <type> taken from the pool <pool_type> if
* available, otherwise returns NULL. No malloc() is attempted, and poisonning
@@ -377,7 +377,7 @@
HA_SPIN_UNLOCK(POOL_LOCK, &pool->lock);
}
}
-#endif /* HA_HAVE_CAS_DW */
+#endif /* CONFIG_HAP_LOCKLESS_POOLS */
#endif /* _COMMON_MEMORY_H */
/*