summaryrefslogtreecommitdiffstats
path: root/kernel/futex
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/futex')
-rw-r--r--kernel/futex/futex.h20
-rw-r--r--kernel/futex/requeue.c3
-rw-r--r--kernel/futex/syscalls.c18
-rw-r--r--kernel/futex/waitwake.c49
4 files changed, 63 insertions, 27 deletions
diff --git a/kernel/futex/futex.h b/kernel/futex/futex.h
index a06030a1a27b..8b195d06f4e8 100644
--- a/kernel/futex/futex.h
+++ b/kernel/futex/futex.h
@@ -52,6 +52,8 @@ static inline unsigned int futex_to_flags(unsigned int op)
return flags;
}
+#define FUTEX2_VALID_MASK (FUTEX2_SIZE_MASK | FUTEX2_PRIVATE)
+
/* FUTEX2_ to FLAGS_ */
static inline unsigned int futex2_to_flags(unsigned int flags2)
{
@@ -137,11 +139,16 @@ struct futex_pi_state {
union futex_key key;
} __randomize_layout;
+struct futex_q;
+typedef void (futex_wake_fn)(struct wake_q_head *wake_q, struct futex_q *q);
+
/**
* struct futex_q - The hashed futex queue entry, one per waiting task
* @list: priority-sorted list of tasks waiting on this futex
* @task: the task waiting on the futex
* @lock_ptr: the hash bucket lock
+ * @wake: the wake handler for this queue
+ * @wake_data: data associated with the wake handler
* @key: the key the futex is hashed on
* @pi_state: optional priority inheritance state
* @rt_waiter: rt_waiter storage for use with requeue_pi
@@ -166,6 +173,8 @@ struct futex_q {
struct task_struct *task;
spinlock_t *lock_ptr;
+ futex_wake_fn *wake;
+ void *wake_data;
union futex_key key;
struct futex_pi_state *pi_state;
struct rt_mutex_waiter *rt_waiter;
@@ -212,6 +221,7 @@ extern int futex_wait_setup(u32 __user *uaddr, u32 val, unsigned int flags,
struct futex_q *q, struct futex_hash_bucket **hb);
extern void futex_wait_queue(struct futex_hash_bucket *hb, struct futex_q *q,
struct hrtimer_sleeper *timeout);
+extern bool __futex_wake_mark(struct futex_q *q);
extern void futex_wake_mark(struct wake_q_head *wake_q, struct futex_q *q);
extern int fault_in_user_writeable(u32 __user *uaddr);
@@ -351,6 +361,16 @@ struct futex_vector {
struct futex_q q;
};
+extern int futex_parse_waitv(struct futex_vector *futexv,
+ struct futex_waitv __user *uwaitv,
+ unsigned int nr_futexes, futex_wake_fn *wake,
+ void *wake_data);
+
+extern int futex_wait_multiple_setup(struct futex_vector *vs, int count,
+ int *woken);
+
+extern int futex_unqueue_multiple(struct futex_vector *v, int count);
+
extern int futex_wait_multiple(struct futex_vector *vs, unsigned int count,
struct hrtimer_sleeper *to);
diff --git a/kernel/futex/requeue.c b/kernel/futex/requeue.c
index 16a3645bd786..eb21f065816b 100644
--- a/kernel/futex/requeue.c
+++ b/kernel/futex/requeue.c
@@ -58,6 +58,7 @@ enum {
const struct futex_q futex_q_init = {
/* list gets initialized in futex_queue()*/
+ .wake = futex_wake_mark,
.key = FUTEX_KEY_INIT,
.bitset = FUTEX_BITSET_MATCH_ANY,
.requeue_state = ATOMIC_INIT(Q_REQUEUE_PI_NONE),
@@ -593,7 +594,7 @@ retry_private:
/* Plain futexes just wake or requeue and are done */
if (!requeue_pi) {
if (++task_count <= nr_wake)
- futex_wake_mark(&wake_q, this);
+ this->wake(&wake_q, this);
else
requeue_futex(this, hb1, hb2, &key2);
continue;
diff --git a/kernel/futex/syscalls.c b/kernel/futex/syscalls.c
index 8200d86d30e1..4b6da9116aa6 100644
--- a/kernel/futex/syscalls.c
+++ b/kernel/futex/syscalls.c
@@ -179,19 +179,20 @@ SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val,
return do_futex(uaddr, op, val, tp, uaddr2, (unsigned long)utime, val3);
}
-#define FUTEX2_VALID_MASK (FUTEX2_SIZE_MASK | FUTEX2_PRIVATE)
-
/**
* futex_parse_waitv - Parse a waitv array from userspace
* @futexv: Kernel side list of waiters to be filled
* @uwaitv: Userspace list to be parsed
* @nr_futexes: Length of futexv
+ * @wake: Wake to call when futex is woken
+ * @wake_data: Data for the wake handler
*
* Return: Error code on failure, 0 on success
*/
-static int futex_parse_waitv(struct futex_vector *futexv,
- struct futex_waitv __user *uwaitv,
- unsigned int nr_futexes)
+int futex_parse_waitv(struct futex_vector *futexv,
+ struct futex_waitv __user *uwaitv,
+ unsigned int nr_futexes, futex_wake_fn *wake,
+ void *wake_data)
{
struct futex_waitv aux;
unsigned int i;
@@ -216,6 +217,8 @@ static int futex_parse_waitv(struct futex_vector *futexv,
futexv[i].w.val = aux.val;
futexv[i].w.uaddr = aux.uaddr;
futexv[i].q = futex_q_init;
+ futexv[i].q.wake = wake;
+ futexv[i].q.wake_data = wake_data;
}
return 0;
@@ -308,7 +311,8 @@ SYSCALL_DEFINE5(futex_waitv, struct futex_waitv __user *, waiters,
goto destroy_timer;
}
- ret = futex_parse_waitv(futexv, waiters, nr_futexes);
+ ret = futex_parse_waitv(futexv, waiters, nr_futexes, futex_wake_mark,
+ NULL);
if (!ret)
ret = futex_wait_multiple(futexv, nr_futexes, timeout ? &to : NULL);
@@ -423,7 +427,7 @@ SYSCALL_DEFINE4(futex_requeue,
if (!waiters)
return -EINVAL;
- ret = futex_parse_waitv(futexes, waiters, 2);
+ ret = futex_parse_waitv(futexes, waiters, 2, futex_wake_mark, NULL);
if (ret)
return ret;
diff --git a/kernel/futex/waitwake.c b/kernel/futex/waitwake.c
index 37860f794bf7..61b112897a84 100644
--- a/kernel/futex/waitwake.c
+++ b/kernel/futex/waitwake.c
@@ -106,20 +106,11 @@
* double_lock_hb() and double_unlock_hb(), respectively.
*/
-/*
- * The hash bucket lock must be held when this is called.
- * Afterwards, the futex_q must not be accessed. Callers
- * must ensure to later call wake_up_q() for the actual
- * wakeups to occur.
- */
-void futex_wake_mark(struct wake_q_head *wake_q, struct futex_q *q)
+bool __futex_wake_mark(struct futex_q *q)
{
- struct task_struct *p = q->task;
-
if (WARN(q->pi_state || q->rt_waiter, "refusing to wake PI futex\n"))
- return;
+ return false;
- get_task_struct(p);
__futex_unqueue(q);
/*
* The waiting task can free the futex_q as soon as q->lock_ptr = NULL
@@ -130,6 +121,26 @@ void futex_wake_mark(struct wake_q_head *wake_q, struct futex_q *q)
*/
smp_store_release(&q->lock_ptr, NULL);
+ return true;
+}
+
+/*
+ * The hash bucket lock must be held when this is called.
+ * Afterwards, the futex_q must not be accessed. Callers
+ * must ensure to later call wake_up_q() for the actual
+ * wakeups to occur.
+ */
+void futex_wake_mark(struct wake_q_head *wake_q, struct futex_q *q)
+{
+ struct task_struct *p = q->task;
+
+ get_task_struct(p);
+
+ if (!__futex_wake_mark(q)) {
+ put_task_struct(p);
+ return;
+ }
+
/*
* Queue the task for later wakeup for after we've released
* the hb->lock.
@@ -177,7 +188,7 @@ int futex_wake(u32 __user *uaddr, unsigned int flags, int nr_wake, u32 bitset)
if (!(this->bitset & bitset))
continue;
- futex_wake_mark(&wake_q, this);
+ this->wake(&wake_q, this);
if (++ret >= nr_wake)
break;
}
@@ -292,7 +303,7 @@ retry_private:
ret = -EINVAL;
goto out_unlock;
}
- futex_wake_mark(&wake_q, this);
+ this->wake(&wake_q, this);
if (++ret >= nr_wake)
break;
}
@@ -306,7 +317,7 @@ retry_private:
ret = -EINVAL;
goto out_unlock;
}
- futex_wake_mark(&wake_q, this);
+ this->wake(&wake_q, this);
if (++op_ret >= nr_wake2)
break;
}
@@ -361,7 +372,7 @@ void futex_wait_queue(struct futex_hash_bucket *hb, struct futex_q *q,
}
/**
- * unqueue_multiple - Remove various futexes from their hash bucket
+ * futex_unqueue_multiple - Remove various futexes from their hash bucket
* @v: The list of futexes to unqueue
* @count: Number of futexes in the list
*
@@ -371,7 +382,7 @@ void futex_wait_queue(struct futex_hash_bucket *hb, struct futex_q *q,
* - >=0 - Index of the last futex that was awoken;
* - -1 - No futex was awoken
*/
-static int unqueue_multiple(struct futex_vector *v, int count)
+int futex_unqueue_multiple(struct futex_vector *v, int count)
{
int ret = -1, i;
@@ -399,7 +410,7 @@ static int unqueue_multiple(struct futex_vector *v, int count)
* - 0 - Success
* - <0 - -EFAULT, -EWOULDBLOCK or -EINVAL
*/
-static int futex_wait_multiple_setup(struct futex_vector *vs, int count, int *woken)
+int futex_wait_multiple_setup(struct futex_vector *vs, int count, int *woken)
{
struct futex_hash_bucket *hb;
bool retry = false;
@@ -461,7 +472,7 @@ retry:
* was woken, we don't return error and return this index to
* userspace
*/
- *woken = unqueue_multiple(vs, i);
+ *woken = futex_unqueue_multiple(vs, i);
if (*woken >= 0)
return 1;
@@ -546,7 +557,7 @@ int futex_wait_multiple(struct futex_vector *vs, unsigned int count,
__set_current_state(TASK_RUNNING);
- ret = unqueue_multiple(vs, count);
+ ret = futex_unqueue_multiple(vs, count);
if (ret >= 0)
return ret;
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-28 17:44:40 +0000