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authorMichael Bestas <mkbestas@lineageos.org>2021-09-16 18:09:37 +0300
committerMichael Bestas <mkbestas@lineageos.org>2021-09-16 18:09:37 +0300
commit1ed76589b97cb8ebafe7d2c78eceea3a22247347 (patch)
tree0b66917f0c332158e45bc444331302dc48b8e820 /kernel/locking
parent42239a8d619a7b7264d77dc9262888f91349d205 (diff)
parent3f066f394dfbaa992235d8c987ded95f7bcd981f (diff)
Merge remote-tracking branch 'common/android-4.4-p' into lineage-18.1-caf-msm8998
# By Thomas Gleixner (11) and others # Via Greg Kroah-Hartman * google/common/android-4.4-p: Linux 4.4.283 Revert "floppy: reintroduce O_NDELAY fix" fbmem: add margin check to fb_check_caps() vt_kdsetmode: extend console locking vringh: Use wiov->used to check for read/write desc order virtio: Improve vq->broken access to avoid any compiler optimization net: marvell: fix MVNETA_TX_IN_PRGRS bit number e1000e: Fix the max snoop/no-snoop latency for 10M USB: serial: option: add new VID/PID to support Fibocom FG150 Revert "USB: serial: ch341: fix character loss at high transfer rates" can: usb: esd_usb2: esd_usb2_rx_event(): fix the interchange of the CAN RX and TX error counters Linux 4.4.282 mmc: dw_mmc: Fix occasional hang after tuning on eMMC ASoC: intel: atom: Fix breakage for PCM buffer address setup ipack: tpci200: fix many double free issues in tpci200_pci_probe ALSA: hda - fix the 'Capture Switch' value change notifications mmc: dw_mmc: Fix hang on data CRC error mmc: dw_mmc: call the dw_mci_prep_stop_abort() by default mmc: dw_mmc: Wait for data transfer after response errors. net: qlcnic: add missed unlock in qlcnic_83xx_flash_read32 net: 6pack: fix slab-out-of-bounds in decode_data dccp: add do-while-0 stubs for dccp_pr_debug macros Bluetooth: hidp: use correct wait queue when removing ctrl_wait scsi: core: Avoid printing an error if target_alloc() returns -ENXIO scsi: megaraid_mm: Fix end of loop tests for list_for_each_entry() dmaengine: of-dma: router_xlate to return -EPROBE_DEFER if controller is not yet available ARM: dts: am43x-epos-evm: Reduce i2c0 bus speed for tps65218 dmaengine: usb-dmac: Fix PM reference leak in usb_dmac_probe() KVM: nSVM: avoid picking up unsupported bits from L2 in int_ctl (CVE-2021-3653) vmlinux.lds.h: Handle clang's module.{c,d}tor sections PCI/MSI: Enforce MSI[X] entry updates to be visible PCI/MSI: Enforce that MSI-X table entry is masked for update PCI/MSI: Mask all unused MSI-X entries PCI/MSI: Protect msi_desc::masked for multi-MSI PCI/MSI: Use msi_mask_irq() in pci_msi_shutdown() PCI/MSI: Correct misleading comments PCI/MSI: Do not set invalid bits in MSI mask PCI/MSI: Enable and mask MSI-X early x86/tools: Fix objdump version check again xen/events: Fix race in set_evtchn_to_irq net: Fix memory leak in ieee802154_raw_deliver i2c: dev: zero out array used for i2c reads from userspace ASoC: intel: atom: Fix reference to PCM buffer address ANDROID: xt_quota2: set usersize in xt_match registration object ANDROID: xt_quota2: clear quota2_log message before sending ANDROID: xt_quota2: remove trailing junk which might have a digit in it UPSTREAM: netfilter: x_tables: fix pointer leaks to userspace Linux 4.4.281 ovl: prevent private clone if bind mount is not allowed net: xilinx_emaclite: Do not print real IOMEM pointer USB:ehci:fix Kunpeng920 ehci hardware problem pipe: increase minimum default pipe size to 2 pages net/qla3xxx: fix schedule while atomic in ql_wait_for_drvr_lock and ql_adapter_reset alpha: Send stop IPI to send to online CPUs reiserfs: check directory items on read from disk reiserfs: add check for root_inode in reiserfs_fill_super pcmcia: i82092: fix a null pointer dereference bug MIPS: Malta: Do not byte-swap accesses to the CBUS UART serial: 8250: Mask out floating 16/32-bit bus bits media: rtl28xxu: fix zero-length control request scripts/tracing: fix the bug that can't parse raw_trace_func USB: serial: ftdi_sio: add device ID for Auto-M3 OP-COM v2 USB: serial: ch341: fix character loss at high transfer rates USB: serial: option: add Telit FD980 composition 0x1056 Bluetooth: defer cleanup of resources in hci_unregister_dev() net: vxge: fix use-after-free in vxge_device_unregister net: pegasus: fix uninit-value in get_interrupt_interval bnx2x: fix an error code in bnx2x_nic_load() mips: Fix non-POSIX regexp net: natsemi: Fix missing pci_disable_device() in probe and remove media: videobuf2-core: dequeue if start_streaming fails scsi: sr: Return correct event when media event code is 3 ALSA: seq: Fix racy deletion of subscriber Linux 4.4.280 rcu: Update documentation of rcu_read_unlock() futex,rt_mutex: Fix rt_mutex_cleanup_proxy_lock() futex: Avoid freeing an active timer futex: Handle transient "ownerless" rtmutex state correctly rtmutex: Make wait_lock irq safe futex: Futex_unlock_pi() determinism futex: Rework futex_lock_pi() to use rt_mutex_*_proxy_lock() futex: Pull rt_mutex_futex_unlock() out from under hb->lock futex,rt_mutex: Introduce rt_mutex_init_waiter() futex: Cleanup refcounting futex: Rename free_pi_state() to put_pi_state() Linux 4.4.279 can: raw: raw_setsockopt(): fix raw_rcv panic for sock UAF Revert "Bluetooth: Shutdown controller after workqueues are flushed or cancelled" net: Fix zero-copy head len calculation. r8152: Fix potential PM refcount imbalance regulator: rt5033: Fix n_voltages settings for BUCK and LDO btrfs: mark compressed range uptodate only if all bio succeed Conflicts: net/bluetooth/hci_core.c net/netfilter/xt_quota2.c Change-Id: I66e2384c8cc40448a7bff34bb935c74e6103e924
Diffstat (limited to 'kernel/locking')
-rw-r--r--kernel/locking/rtmutex.c185
-rw-r--r--kernel/locking/rtmutex_common.h2
2 files changed, 101 insertions, 86 deletions
diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c
index 1c0cb5c3c6ad..532986d82179 100644
--- a/kernel/locking/rtmutex.c
+++ b/kernel/locking/rtmutex.c
@@ -163,13 +163,14 @@ static inline void mark_rt_mutex_waiters(struct rt_mutex *lock)
* 2) Drop lock->wait_lock
* 3) Try to unlock the lock with cmpxchg
*/
-static inline bool unlock_rt_mutex_safe(struct rt_mutex *lock)
+static inline bool unlock_rt_mutex_safe(struct rt_mutex *lock,
+ unsigned long flags)
__releases(lock->wait_lock)
{
struct task_struct *owner = rt_mutex_owner(lock);
clear_rt_mutex_waiters(lock);
- raw_spin_unlock(&lock->wait_lock);
+ raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
/*
* If a new waiter comes in between the unlock and the cmpxchg
* we have two situations:
@@ -211,11 +212,12 @@ static inline void mark_rt_mutex_waiters(struct rt_mutex *lock)
/*
* Simple slow path only version: lock->owner is protected by lock->wait_lock.
*/
-static inline bool unlock_rt_mutex_safe(struct rt_mutex *lock)
+static inline bool unlock_rt_mutex_safe(struct rt_mutex *lock,
+ unsigned long flags)
__releases(lock->wait_lock)
{
lock->owner = NULL;
- raw_spin_unlock(&lock->wait_lock);
+ raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
return true;
}
#endif
@@ -497,7 +499,6 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
int ret = 0, depth = 0;
struct rt_mutex *lock;
bool detect_deadlock;
- unsigned long flags;
bool requeue = true;
detect_deadlock = rt_mutex_cond_detect_deadlock(orig_waiter, chwalk);
@@ -540,7 +541,7 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
/*
* [1] Task cannot go away as we did a get_task() before !
*/
- raw_spin_lock_irqsave(&task->pi_lock, flags);
+ raw_spin_lock_irq(&task->pi_lock);
/*
* [2] Get the waiter on which @task is blocked on.
@@ -624,7 +625,7 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
* operations.
*/
if (!raw_spin_trylock(&lock->wait_lock)) {
- raw_spin_unlock_irqrestore(&task->pi_lock, flags);
+ raw_spin_unlock_irq(&task->pi_lock);
cpu_relax();
goto retry;
}
@@ -655,7 +656,7 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
/*
* No requeue[7] here. Just release @task [8]
*/
- raw_spin_unlock_irqrestore(&task->pi_lock, flags);
+ raw_spin_unlock(&task->pi_lock);
put_task_struct(task);
/*
@@ -663,14 +664,14 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
* If there is no owner of the lock, end of chain.
*/
if (!rt_mutex_owner(lock)) {
- raw_spin_unlock(&lock->wait_lock);
+ raw_spin_unlock_irq(&lock->wait_lock);
return 0;
}
/* [10] Grab the next task, i.e. owner of @lock */
task = rt_mutex_owner(lock);
get_task_struct(task);
- raw_spin_lock_irqsave(&task->pi_lock, flags);
+ raw_spin_lock(&task->pi_lock);
/*
* No requeue [11] here. We just do deadlock detection.
@@ -685,8 +686,8 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
top_waiter = rt_mutex_top_waiter(lock);
/* [13] Drop locks */
- raw_spin_unlock_irqrestore(&task->pi_lock, flags);
- raw_spin_unlock(&lock->wait_lock);
+ raw_spin_unlock(&task->pi_lock);
+ raw_spin_unlock_irq(&lock->wait_lock);
/* If owner is not blocked, end of chain. */
if (!next_lock)
@@ -707,7 +708,7 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
rt_mutex_enqueue(lock, waiter);
/* [8] Release the task */
- raw_spin_unlock_irqrestore(&task->pi_lock, flags);
+ raw_spin_unlock(&task->pi_lock);
put_task_struct(task);
/*
@@ -725,14 +726,14 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
*/
if (prerequeue_top_waiter != rt_mutex_top_waiter(lock))
wake_up_process(rt_mutex_top_waiter(lock)->task);
- raw_spin_unlock(&lock->wait_lock);
+ raw_spin_unlock_irq(&lock->wait_lock);
return 0;
}
/* [10] Grab the next task, i.e. the owner of @lock */
task = rt_mutex_owner(lock);
get_task_struct(task);
- raw_spin_lock_irqsave(&task->pi_lock, flags);
+ raw_spin_lock(&task->pi_lock);
/* [11] requeue the pi waiters if necessary */
if (waiter == rt_mutex_top_waiter(lock)) {
@@ -786,8 +787,8 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
top_waiter = rt_mutex_top_waiter(lock);
/* [13] Drop the locks */
- raw_spin_unlock_irqrestore(&task->pi_lock, flags);
- raw_spin_unlock(&lock->wait_lock);
+ raw_spin_unlock(&task->pi_lock);
+ raw_spin_unlock_irq(&lock->wait_lock);
/*
* Make the actual exit decisions [12], based on the stored
@@ -810,7 +811,7 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
goto again;
out_unlock_pi:
- raw_spin_unlock_irqrestore(&task->pi_lock, flags);
+ raw_spin_unlock_irq(&task->pi_lock);
out_put_task:
put_task_struct(task);
@@ -820,7 +821,7 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
/*
* Try to take an rt-mutex
*
- * Must be called with lock->wait_lock held.
+ * Must be called with lock->wait_lock held and interrupts disabled
*
* @lock: The lock to be acquired.
* @task: The task which wants to acquire the lock
@@ -830,8 +831,6 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
static int try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task,
struct rt_mutex_waiter *waiter)
{
- unsigned long flags;
-
/*
* Before testing whether we can acquire @lock, we set the
* RT_MUTEX_HAS_WAITERS bit in @lock->owner. This forces all
@@ -916,7 +915,7 @@ static int try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task,
* case, but conditionals are more expensive than a redundant
* store.
*/
- raw_spin_lock_irqsave(&task->pi_lock, flags);
+ raw_spin_lock(&task->pi_lock);
task->pi_blocked_on = NULL;
/*
* Finish the lock acquisition. @task is the new owner. If
@@ -925,7 +924,7 @@ static int try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task,
*/
if (rt_mutex_has_waiters(lock))
rt_mutex_enqueue_pi(task, rt_mutex_top_waiter(lock));
- raw_spin_unlock_irqrestore(&task->pi_lock, flags);
+ raw_spin_unlock(&task->pi_lock);
takeit:
/* We got the lock. */
@@ -945,7 +944,7 @@ takeit:
*
* Prepare waiter and propagate pi chain
*
- * This must be called with lock->wait_lock held.
+ * This must be called with lock->wait_lock held and interrupts disabled
*/
static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
struct rt_mutex_waiter *waiter,
@@ -956,7 +955,6 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
struct rt_mutex_waiter *top_waiter = waiter;
struct rt_mutex *next_lock;
int chain_walk = 0, res;
- unsigned long flags;
/*
* Early deadlock detection. We really don't want the task to
@@ -970,7 +968,7 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
if (owner == task)
return -EDEADLK;
- raw_spin_lock_irqsave(&task->pi_lock, flags);
+ raw_spin_lock(&task->pi_lock);
__rt_mutex_adjust_prio(task);
waiter->task = task;
waiter->lock = lock;
@@ -983,12 +981,12 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
task->pi_blocked_on = waiter;
- raw_spin_unlock_irqrestore(&task->pi_lock, flags);
+ raw_spin_unlock(&task->pi_lock);
if (!owner)
return 0;
- raw_spin_lock_irqsave(&owner->pi_lock, flags);
+ raw_spin_lock(&owner->pi_lock);
if (waiter == rt_mutex_top_waiter(lock)) {
rt_mutex_dequeue_pi(owner, top_waiter);
rt_mutex_enqueue_pi(owner, waiter);
@@ -1003,7 +1001,7 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
/* Store the lock on which owner is blocked or NULL */
next_lock = task_blocked_on_lock(owner);
- raw_spin_unlock_irqrestore(&owner->pi_lock, flags);
+ raw_spin_unlock(&owner->pi_lock);
/*
* Even if full deadlock detection is on, if the owner is not
* blocked itself, we can avoid finding this out in the chain
@@ -1019,12 +1017,12 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
*/
get_task_struct(owner);
- raw_spin_unlock(&lock->wait_lock);
+ raw_spin_unlock_irq(&lock->wait_lock);
res = rt_mutex_adjust_prio_chain(owner, chwalk, lock,
next_lock, waiter, task);
- raw_spin_lock(&lock->wait_lock);
+ raw_spin_lock_irq(&lock->wait_lock);
return res;
}
@@ -1033,15 +1031,14 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
* Remove the top waiter from the current tasks pi waiter tree and
* queue it up.
*
- * Called with lock->wait_lock held.
+ * Called with lock->wait_lock held and interrupts disabled.
*/
static void mark_wakeup_next_waiter(struct wake_q_head *wake_q,
struct rt_mutex *lock)
{
struct rt_mutex_waiter *waiter;
- unsigned long flags;
- raw_spin_lock_irqsave(&current->pi_lock, flags);
+ raw_spin_lock(&current->pi_lock);
waiter = rt_mutex_top_waiter(lock);
@@ -1063,7 +1060,7 @@ static void mark_wakeup_next_waiter(struct wake_q_head *wake_q,
*/
lock->owner = (void *) RT_MUTEX_HAS_WAITERS;
- raw_spin_unlock_irqrestore(&current->pi_lock, flags);
+ raw_spin_unlock(&current->pi_lock);
wake_q_add(wake_q, waiter->task);
}
@@ -1071,7 +1068,7 @@ static void mark_wakeup_next_waiter(struct wake_q_head *wake_q,
/*
* Remove a waiter from a lock and give up
*
- * Must be called with lock->wait_lock held and
+ * Must be called with lock->wait_lock held and interrupts disabled. I must
* have just failed to try_to_take_rt_mutex().
*/
static void remove_waiter(struct rt_mutex *lock,
@@ -1080,12 +1077,11 @@ static void remove_waiter(struct rt_mutex *lock,
bool is_top_waiter = (waiter == rt_mutex_top_waiter(lock));
struct task_struct *owner = rt_mutex_owner(lock);
struct rt_mutex *next_lock;
- unsigned long flags;
- raw_spin_lock_irqsave(&current->pi_lock, flags);
+ raw_spin_lock(&current->pi_lock);
rt_mutex_dequeue(lock, waiter);
current->pi_blocked_on = NULL;
- raw_spin_unlock_irqrestore(&current->pi_lock, flags);
+ raw_spin_unlock(&current->pi_lock);
/*
* Only update priority if the waiter was the highest priority
@@ -1094,7 +1090,7 @@ static void remove_waiter(struct rt_mutex *lock,
if (!owner || !is_top_waiter)
return;
- raw_spin_lock_irqsave(&owner->pi_lock, flags);
+ raw_spin_lock(&owner->pi_lock);
rt_mutex_dequeue_pi(owner, waiter);
@@ -1106,7 +1102,7 @@ static void remove_waiter(struct rt_mutex *lock,
/* Store the lock on which owner is blocked or NULL */
next_lock = task_blocked_on_lock(owner);
- raw_spin_unlock_irqrestore(&owner->pi_lock, flags);
+ raw_spin_unlock(&owner->pi_lock);
/*
* Don't walk the chain, if the owner task is not blocked
@@ -1118,12 +1114,12 @@ static void remove_waiter(struct rt_mutex *lock,
/* gets dropped in rt_mutex_adjust_prio_chain()! */
get_task_struct(owner);
- raw_spin_unlock(&lock->wait_lock);
+ raw_spin_unlock_irq(&lock->wait_lock);
rt_mutex_adjust_prio_chain(owner, RT_MUTEX_MIN_CHAINWALK, lock,
next_lock, NULL, current);
- raw_spin_lock(&lock->wait_lock);
+ raw_spin_lock_irq(&lock->wait_lock);
}
/*
@@ -1155,15 +1151,23 @@ void rt_mutex_adjust_pi(struct task_struct *task)
next_lock, NULL, task);
}
+void rt_mutex_init_waiter(struct rt_mutex_waiter *waiter)
+{
+ debug_rt_mutex_init_waiter(waiter);
+ RB_CLEAR_NODE(&waiter->pi_tree_entry);
+ RB_CLEAR_NODE(&waiter->tree_entry);
+ waiter->task = NULL;
+}
+
/**
* __rt_mutex_slowlock() - Perform the wait-wake-try-to-take loop
* @lock: the rt_mutex to take
* @state: the state the task should block in (TASK_INTERRUPTIBLE
- * or TASK_UNINTERRUPTIBLE)
+ * or TASK_UNINTERRUPTIBLE)
* @timeout: the pre-initialized and started timer, or NULL for none
* @waiter: the pre-initialized rt_mutex_waiter
*
- * lock->wait_lock must be held by the caller.
+ * Must be called with lock->wait_lock held and interrupts disabled
*/
static int __sched
__rt_mutex_slowlock(struct rt_mutex *lock, int state,
@@ -1191,13 +1195,13 @@ __rt_mutex_slowlock(struct rt_mutex *lock, int state,
break;
}
- raw_spin_unlock(&lock->wait_lock);
+ raw_spin_unlock_irq(&lock->wait_lock);
debug_rt_mutex_print_deadlock(waiter);
schedule();
- raw_spin_lock(&lock->wait_lock);
+ raw_spin_lock_irq(&lock->wait_lock);
set_current_state(state);
}
@@ -1234,17 +1238,24 @@ rt_mutex_slowlock(struct rt_mutex *lock, int state,
enum rtmutex_chainwalk chwalk)
{
struct rt_mutex_waiter waiter;
+ unsigned long flags;
int ret = 0;
- debug_rt_mutex_init_waiter(&waiter);
- RB_CLEAR_NODE(&waiter.pi_tree_entry);
- RB_CLEAR_NODE(&waiter.tree_entry);
+ rt_mutex_init_waiter(&waiter);
- raw_spin_lock(&lock->wait_lock);
+ /*
+ * Technically we could use raw_spin_[un]lock_irq() here, but this can
+ * be called in early boot if the cmpxchg() fast path is disabled
+ * (debug, no architecture support). In this case we will acquire the
+ * rtmutex with lock->wait_lock held. But we cannot unconditionally
+ * enable interrupts in that early boot case. So we need to use the
+ * irqsave/restore variants.
+ */
+ raw_spin_lock_irqsave(&lock->wait_lock, flags);
/* Try to acquire the lock again: */
if (try_to_take_rt_mutex(lock, current, NULL)) {
- raw_spin_unlock(&lock->wait_lock);
+ raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
return 0;
}
@@ -1273,7 +1284,7 @@ rt_mutex_slowlock(struct rt_mutex *lock, int state,
*/
fixup_rt_mutex_waiters(lock);
- raw_spin_unlock(&lock->wait_lock);
+ raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
/* Remove pending timer: */
if (unlikely(timeout))
@@ -1302,6 +1313,7 @@ static inline int __rt_mutex_slowtrylock(struct rt_mutex *lock)
*/
static inline int rt_mutex_slowtrylock(struct rt_mutex *lock)
{
+ unsigned long flags;
int ret;
/*
@@ -1313,14 +1325,14 @@ static inline int rt_mutex_slowtrylock(struct rt_mutex *lock)
return 0;
/*
- * The mutex has currently no owner. Lock the wait lock and
- * try to acquire the lock.
+ * The mutex has currently no owner. Lock the wait lock and try to
+ * acquire the lock. We use irqsave here to support early boot calls.
*/
- raw_spin_lock(&lock->wait_lock);
+ raw_spin_lock_irqsave(&lock->wait_lock, flags);
ret = __rt_mutex_slowtrylock(lock);
- raw_spin_unlock(&lock->wait_lock);
+ raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
return ret;
}
@@ -1332,7 +1344,10 @@ static inline int rt_mutex_slowtrylock(struct rt_mutex *lock)
static bool __sched rt_mutex_slowunlock(struct rt_mutex *lock,
struct wake_q_head *wake_q)
{
- raw_spin_lock(&lock->wait_lock);
+ unsigned long flags;
+
+ /* irqsave required to support early boot calls */
+ raw_spin_lock_irqsave(&lock->wait_lock, flags);
debug_rt_mutex_unlock(lock);
@@ -1369,10 +1384,10 @@ static bool __sched rt_mutex_slowunlock(struct rt_mutex *lock,
*/
while (!rt_mutex_has_waiters(lock)) {
/* Drops lock->wait_lock ! */
- if (unlock_rt_mutex_safe(lock) == true)
+ if (unlock_rt_mutex_safe(lock, flags) == true)
return false;
/* Relock the rtmutex and try again */
- raw_spin_lock(&lock->wait_lock);
+ raw_spin_lock_irqsave(&lock->wait_lock, flags);
}
/*
@@ -1383,7 +1398,7 @@ static bool __sched rt_mutex_slowunlock(struct rt_mutex *lock,
*/
mark_wakeup_next_waiter(wake_q, lock);
- raw_spin_unlock(&lock->wait_lock);
+ raw_spin_unlock_irqrestore(&lock->wait_lock, flags);
/* check PI boosting */
return true;
@@ -1483,19 +1498,6 @@ int __sched rt_mutex_lock_interruptible(struct rt_mutex *lock)
EXPORT_SYMBOL_GPL(rt_mutex_lock_interruptible);
/*
- * Futex variant with full deadlock detection.
- * Futex variants must not use the fast-path, see __rt_mutex_futex_unlock().
- */
-int __sched rt_mutex_timed_futex_lock(struct rt_mutex *lock,
- struct hrtimer_sleeper *timeout)
-{
- might_sleep();
-
- return rt_mutex_slowlock(lock, TASK_INTERRUPTIBLE,
- timeout, RT_MUTEX_FULL_CHAINWALK);
-}
-
-/*
* Futex variant, must not use fastpath.
*/
int __sched rt_mutex_futex_trylock(struct rt_mutex *lock)
@@ -1687,10 +1689,10 @@ int rt_mutex_start_proxy_lock(struct rt_mutex *lock,
{
int ret;
- raw_spin_lock(&lock->wait_lock);
+ raw_spin_lock_irq(&lock->wait_lock);
if (try_to_take_rt_mutex(lock, task, NULL)) {
- raw_spin_unlock(&lock->wait_lock);
+ raw_spin_unlock_irq(&lock->wait_lock);
return 1;
}
@@ -1711,7 +1713,7 @@ int rt_mutex_start_proxy_lock(struct rt_mutex *lock,
if (unlikely(ret))
remove_waiter(lock, waiter);
- raw_spin_unlock(&lock->wait_lock);
+ raw_spin_unlock_irq(&lock->wait_lock);
debug_rt_mutex_print_deadlock(waiter);
@@ -1761,20 +1763,16 @@ int rt_mutex_wait_proxy_lock(struct rt_mutex *lock,
{
int ret;
- raw_spin_lock(&lock->wait_lock);
-
- set_current_state(TASK_INTERRUPTIBLE);
-
+ raw_spin_lock_irq(&lock->wait_lock);
/* sleep on the mutex */
+ set_current_state(TASK_INTERRUPTIBLE);
ret = __rt_mutex_slowlock(lock, TASK_INTERRUPTIBLE, to, waiter);
-
/*
* try_to_take_rt_mutex() sets the waiter bit unconditionally. We might
* have to fix that up.
*/
fixup_rt_mutex_waiters(lock);
-
- raw_spin_unlock(&lock->wait_lock);
+ raw_spin_unlock_irq(&lock->wait_lock);
return ret;
}
@@ -1805,14 +1803,31 @@ bool rt_mutex_cleanup_proxy_lock(struct rt_mutex *lock,
raw_spin_lock_irq(&lock->wait_lock);
/*
+ * Do an unconditional try-lock, this deals with the lock stealing
+ * state where __rt_mutex_futex_unlock() -> mark_wakeup_next_waiter()
+ * sets a NULL owner.
+ *
+ * We're not interested in the return value, because the subsequent
+ * test on rt_mutex_owner() will infer that. If the trylock succeeded,
+ * we will own the lock and it will have removed the waiter. If we
+ * failed the trylock, we're still not owner and we need to remove
+ * ourselves.
+ */
+ try_to_take_rt_mutex(lock, current, waiter);
+ /*
* Unless we're the owner; we're still enqueued on the wait_list.
* So check if we became owner, if not, take us off the wait_list.
*/
if (rt_mutex_owner(lock) != current) {
remove_waiter(lock, waiter);
- fixup_rt_mutex_waiters(lock);
cleanup = true;
}
+ /*
+ * try_to_take_rt_mutex() sets the waiter bit unconditionally. We might
+ * have to fix that up.
+ */
+ fixup_rt_mutex_waiters(lock);
+
raw_spin_unlock_irq(&lock->wait_lock);
return cleanup;
diff --git a/kernel/locking/rtmutex_common.h b/kernel/locking/rtmutex_common.h
index 4584db96265d..97c048c494f0 100644
--- a/kernel/locking/rtmutex_common.h
+++ b/kernel/locking/rtmutex_common.h
@@ -102,6 +102,7 @@ extern struct task_struct *rt_mutex_next_owner(struct rt_mutex *lock);
extern void rt_mutex_init_proxy_locked(struct rt_mutex *lock,
struct task_struct *proxy_owner);
extern void rt_mutex_proxy_unlock(struct rt_mutex *lock);
+extern void rt_mutex_init_waiter(struct rt_mutex_waiter *waiter);
extern int rt_mutex_start_proxy_lock(struct rt_mutex *lock,
struct rt_mutex_waiter *waiter,
struct task_struct *task);
@@ -110,7 +111,6 @@ extern int rt_mutex_wait_proxy_lock(struct rt_mutex *lock,
struct rt_mutex_waiter *waiter);
extern bool rt_mutex_cleanup_proxy_lock(struct rt_mutex *lock,
struct rt_mutex_waiter *waiter);
-extern int rt_mutex_timed_futex_lock(struct rt_mutex *l, struct hrtimer_sleeper *to);
extern int rt_mutex_futex_trylock(struct rt_mutex *l);
extern int __rt_mutex_futex_trylock(struct rt_mutex *l);