Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip (0e11d256) · Commits · 戴 / test

include/asm-generic/futex.h

+6 −2

Original line number	Diff line number	Diff line
		@@ -108,11 +108,15 @@ futex_atomic_cmpxchg_inatomic(u32 uval, u32 __user uaddr,
		u32 val;

		preempt_disable();
		if (unlikely(get_user(val, uaddr) != 0))
		if (unlikely(get_user(val, uaddr) != 0)) {
		preempt_enable();
		return -EFAULT;
		}

		if (val == oldval && unlikely(put_user(newval, uaddr) != 0))
		if (val == oldval && unlikely(put_user(newval, uaddr) != 0)) {
		preempt_enable();
		return -EFAULT;
		}

		*uval = val;
		preempt_enable();

+23 −4

Original line number	Diff line number	Diff line
		@@ -1295,10 +1295,20 @@ static int wake_futex_pi(u32 __user uaddr, u32 uval, struct futex_q this,
		if (unlikely(should_fail_futex(true)))
		ret = -EFAULT;

		if (cmpxchg_futex_value_locked(&curval, uaddr, uval, newval))
		if (cmpxchg_futex_value_locked(&curval, uaddr, uval, newval)) {
		ret = -EFAULT;
		else if (curval != uval)
		} else if (curval != uval) {
		/*
		* If a unconditional UNLOCK_PI operation (user space did not
		* try the TID->0 transition) raced with a waiter setting the
		* FUTEX_WAITERS flag between get_user() and locking the hash
		* bucket lock, retry the operation.
		*/
		if ((FUTEX_TID_MASK & curval) == uval)
		ret = -EAGAIN;
		else
		ret = -EINVAL;
		}
		if (ret) {
		raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock);
		return ret;
		@@ -1525,8 +1535,8 @@ void requeue_futex(struct futex_q q, struct futex_hash_bucket hb1,
		if (likely(&hb1->chain != &hb2->chain)) {
		plist_del(&q->list, &hb1->chain);
		hb_waiters_dec(hb1);
		plist_add(&q->list, &hb2->chain);
		hb_waiters_inc(hb2);
		plist_add(&q->list, &hb2->chain);
		q->lock_ptr = &hb2->lock;
		}
		get_futex_key_refs(key2);
		@@ -2622,6 +2632,15 @@ retry:
		*/
		if (ret == -EFAULT)
		goto pi_faulted;
		/*
		* A unconditional UNLOCK_PI op raced against a waiter
		* setting the FUTEX_WAITERS bit. Try again.
		*/
		if (ret == -EAGAIN) {
		spin_unlock(&hb->lock);
		put_futex_key(&key);
		goto retry;
		}
		/*
		* wake_futex_pi has detected invalid state. Tell user
		* space.

+5 −3

Original line number	Diff line number	Diff line
		@@ -136,10 +136,12 @@ static ssize_t qstat_read(struct file file, char __user user_buf,
		}

		if (counter == qstat_pv_hash_hops) {
		u64 frac;
		u64 frac = 0;

		if (kicks) {
		frac = 100ULL * do_div(stat, kicks);
		frac = DIV_ROUND_CLOSEST_ULL(frac, kicks);
		}

		/*
		* Return a X.XX decimal number