It looks like bnep_session has same pattern as the issue reported in
old rfcomm:
while (1) {
set_current_state(TASK_INTERRUPTIBLE);
if (condition)
break;
// may call might_sleep here
schedule();
}
__set_current_state(TASK_RUNNING);
Which fixed at:
dfb2fae Bluetooth: Fix nested sleeps
So let's fix it at the same way, also follow the suggestion of:
https://lwn.net/Articles/628628/
Signed-off-by: Jeffy Chen <[email protected]>
Reviewed-by: Brian Norris <[email protected]>
---
Changes in v3:
Add brian's Reviewed-by.
Changes in v2:
Remove unnecessary memory barrier before wake_up_* functions.
net/bluetooth/bnep/core.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)
diff --git a/net/bluetooth/bnep/core.c b/net/bluetooth/bnep/core.c
index fbf251f..4d6b94d 100644
--- a/net/bluetooth/bnep/core.c
+++ b/net/bluetooth/bnep/core.c
@@ -484,16 +484,16 @@ static int bnep_session(void *arg)
struct net_device *dev = s->dev;
struct sock *sk = s->sock->sk;
struct sk_buff *skb;
- wait_queue_t wait;
+ DEFINE_WAIT_FUNC(wait, woken_wake_function);
BT_DBG("");
set_user_nice(current, -15);
- init_waitqueue_entry(&wait, current);
add_wait_queue(sk_sleep(sk), &wait);
while (1) {
- set_current_state(TASK_INTERRUPTIBLE);
+ /* Ensure session->terminate is updated */
+ smp_mb__before_atomic();
if (atomic_read(&s->terminate))
break;
@@ -515,9 +515,8 @@ static int bnep_session(void *arg)
break;
netif_wake_queue(dev);
- schedule();
+ wait_woken(&wait, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
}
- __set_current_state(TASK_RUNNING);
remove_wait_queue(sk_sleep(sk), &wait);
/* Cleanup session */
@@ -666,7 +665,7 @@ int bnep_del_connection(struct bnep_conndel_req *req)
s = __bnep_get_session(req->dst);
if (s) {
atomic_inc(&s->terminate);
- wake_up_process(s->task);
+ wake_up_interruptible(sk_sleep(s->sock->sk));
} else
err = -ENOENT;
--
2.1.4
It looks like hidp_session_thread has same pattern as the issue reported in
old rfcomm:
while (1) {
set_current_state(TASK_INTERRUPTIBLE);
if (condition)
break;
// may call might_sleep here
schedule();
}
__set_current_state(TASK_RUNNING);
Which fixed at:
dfb2fae Bluetooth: Fix nested sleeps
So let's fix it at the same way, also follow the suggestion of:
https://lwn.net/Articles/628628/
Signed-off-by: Jeffy Chen <[email protected]>
1/ Fix could not wake up by wake attempts on original wait queues.
2/ Remove unnecessary memory barrier before wake_up_* functions.
1/ Make hidp_session_wake_function static.
2/ Remove unnecessary default_wake_function.
---
Changes in v3: None
Changes in v2: None
net/bluetooth/hidp/core.c | 33 ++++++++++++++++++++++-----------
1 file changed, 22 insertions(+), 11 deletions(-)
diff --git a/net/bluetooth/hidp/core.c b/net/bluetooth/hidp/core.c
index 0bec458..1fc0764 100644
--- a/net/bluetooth/hidp/core.c
+++ b/net/bluetooth/hidp/core.c
@@ -36,6 +36,7 @@
#define VERSION "1.2"
static DECLARE_RWSEM(hidp_session_sem);
+static DECLARE_WAIT_QUEUE_HEAD(hidp_session_wq);
static LIST_HEAD(hidp_session_list);
static unsigned char hidp_keycode[256] = {
@@ -1068,12 +1069,12 @@ static int hidp_session_start_sync(struct hidp_session *session)
* Wake up session thread and notify it to stop. This is asynchronous and
* returns immediately. Call this whenever a runtime error occurs and you want
* the session to stop.
- * Note: wake_up_process() performs any necessary memory-barriers for us.
+ * Note: wake_up_interruptible() performs any necessary memory-barriers for us.
*/
static void hidp_session_terminate(struct hidp_session *session)
{
atomic_inc(&session->terminate);
- wake_up_process(session->task);
+ wake_up_interruptible(&hidp_session_wq);
}
/*
@@ -1180,7 +1181,9 @@ static void hidp_session_run(struct hidp_session *session)
struct sock *ctrl_sk = session->ctrl_sock->sk;
struct sock *intr_sk = session->intr_sock->sk;
struct sk_buff *skb;
+ DEFINE_WAIT_FUNC(wait, woken_wake_function);
+ add_wait_queue(&hidp_session_wq, &wait);
for (;;) {
/*
* This thread can be woken up two ways:
@@ -1188,12 +1191,10 @@ static void hidp_session_run(struct hidp_session *session)
* session->terminate flag and wakes this thread up.
* - Via modifying the socket state of ctrl/intr_sock. This
* thread is woken up by ->sk_state_changed().
- *
- * Note: set_current_state() performs any necessary
- * memory-barriers for us.
*/
- set_current_state(TASK_INTERRUPTIBLE);
+ /* Ensure session->terminate is updated */
+ smp_mb__before_atomic();
if (atomic_read(&session->terminate))
break;
@@ -1227,11 +1228,22 @@ static void hidp_session_run(struct hidp_session *session)
hidp_process_transmit(session, &session->ctrl_transmit,
session->ctrl_sock);
- schedule();
+ wait_woken(&wait, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
}
+ remove_wait_queue(&hidp_session_wq, &wait);
atomic_inc(&session->terminate);
- set_current_state(TASK_RUNNING);
+
+ /* Ensure session->terminate is updated */
+ smp_mb__after_atomic();
+}
+
+static int hidp_session_wake_function(wait_queue_t *wait,
+ unsigned int mode,
+ int sync, void *key)
+{
+ wake_up_interruptible(&hidp_session_wq);
+ return false;
}
/*
@@ -1244,7 +1256,8 @@ static void hidp_session_run(struct hidp_session *session)
static int hidp_session_thread(void *arg)
{
struct hidp_session *session = arg;
- wait_queue_t ctrl_wait, intr_wait;
+ DEFINE_WAIT_FUNC(ctrl_wait, hidp_session_wake_function);
+ DEFINE_WAIT_FUNC(intr_wait, hidp_session_wake_function);
BT_DBG("session %p", session);
@@ -1254,8 +1267,6 @@ static int hidp_session_thread(void *arg)
set_user_nice(current, -15);
hidp_set_timer(session);
- init_waitqueue_entry(&ctrl_wait, current);
- init_waitqueue_entry(&intr_wait, current);
add_wait_queue(sk_sleep(session->ctrl_sock->sk), &ctrl_wait);
add_wait_queue(sk_sleep(session->intr_sock->sk), &intr_wait);
/* This memory barrier is paired with wq_has_sleeper(). See
--
2.1.4
It looks like cmtp_session has same pattern as the issue reported in
old rfcomm:
while (1) {
set_current_state(TASK_INTERRUPTIBLE);
if (condition)
break;
// may call might_sleep here
schedule();
}
__set_current_state(TASK_RUNNING);
Which fixed at:
dfb2fae Bluetooth: Fix nested sleeps
So let's fix it at the same way, also follow the suggestion of:
https://lwn.net/Articles/628628/
Signed-off-by: Jeffy Chen <[email protected]>
Reviewed-by: Brian Norris <[email protected]>
Remove unnecessary memory barrier before wake_up_* functions.
---
Changes in v3:
Add brian's Reviewed-by.
Changes in v2: None
net/bluetooth/cmtp/core.c | 17 ++++++++++-------
1 file changed, 10 insertions(+), 7 deletions(-)
diff --git a/net/bluetooth/cmtp/core.c b/net/bluetooth/cmtp/core.c
index 9e59b66..1152ce3 100644
--- a/net/bluetooth/cmtp/core.c
+++ b/net/bluetooth/cmtp/core.c
@@ -280,16 +280,16 @@ static int cmtp_session(void *arg)
struct cmtp_session *session = arg;
struct sock *sk = session->sock->sk;
struct sk_buff *skb;
- wait_queue_t wait;
+ DEFINE_WAIT_FUNC(wait, woken_wake_function);
BT_DBG("session %p", session);
set_user_nice(current, -15);
- init_waitqueue_entry(&wait, current);
add_wait_queue(sk_sleep(sk), &wait);
while (1) {
- set_current_state(TASK_INTERRUPTIBLE);
+ /* Ensure session->terminate is updated */
+ smp_mb__before_atomic();
if (atomic_read(&session->terminate))
break;
@@ -306,9 +306,8 @@ static int cmtp_session(void *arg)
cmtp_process_transmit(session);
- schedule();
+ wait_woken(&wait, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
}
- __set_current_state(TASK_RUNNING);
remove_wait_queue(sk_sleep(sk), &wait);
down_write(&cmtp_session_sem);
@@ -393,7 +392,7 @@ int cmtp_add_connection(struct cmtp_connadd_req *req, struct socket *sock)
err = cmtp_attach_device(session);
if (err < 0) {
atomic_inc(&session->terminate);
- wake_up_process(session->task);
+ wake_up_interruptible(sk_sleep(session->sock->sk));
up_write(&cmtp_session_sem);
return err;
}
@@ -431,7 +430,11 @@ int cmtp_del_connection(struct cmtp_conndel_req *req)
/* Stop session thread */
atomic_inc(&session->terminate);
- wake_up_process(session->task);
+
+ /* Ensure session->terminate is updated */
+ smp_mb__after_atomic();
+
+ wake_up_interruptible(sk_sleep(session->sock->sk));
} else
err = -ENOENT;
--
2.1.4
On Tue, 2017-02-14 at 08:55 +0800, Jeffy Chen wrote:
> It looks like hidp_session_thread has same pattern as the issue
> reported in
> old rfcomm:
>
> while (1) {
> set_current_state(TASK_INTERRUPTIBLE);
> if (condition)
> break;
> // may call might_sleep here
> schedule();
> }
> __set_current_state(TASK_RUNNING);
>
> Which fixed at:
> dfb2fae Bluetooth: Fix nested sleeps
>
> So let's fix it at the same way, also follow the suggestion of:
> https://lwn.net/Articles/628628/
>
> Signed-off-by: Jeffy Chen <[email protected]>
> 1/ Fix could not wake up by wake attempts on original wait queues.
> 2/ Remove unnecessary memory barrier before wake_up_* functions.
>
> 1/ Make hidp_session_wake_function static.
> 2/ Remove unnecessary default_wake_function.
>
Tested-by: AL Yu-Chen Cho <[email protected]>
> ---
>
> Changes in v3: None
> Changes in v2: None
>
> net/bluetooth/hidp/core.c | 33 ++++++++++++++++++++++-----------
> 1 file changed, 22 insertions(+), 11 deletions(-)
>
> diff --git a/net/bluetooth/hidp/core.c b/net/bluetooth/hidp/core.c
> index 0bec458..1fc0764 100644
> --- a/net/bluetooth/hidp/core.c
> +++ b/net/bluetooth/hidp/core.c
> @@ -36,6 +36,7 @@
> #define VERSION "1.2"
>
> static DECLARE_RWSEM(hidp_session_sem);
> +static DECLARE_WAIT_QUEUE_HEAD(hidp_session_wq);
> static LIST_HEAD(hidp_session_list);
>
> static unsigned char hidp_keycode[256] = {
> @@ -1068,12 +1069,12 @@ static int hidp_session_start_sync(struct
> hidp_session *session)
> * Wake up session thread and notify it to stop. This is
> asynchronous and
> * returns immediately. Call this whenever a runtime error occurs
> and you want
> * the session to stop.
> - * Note: wake_up_process() performs any necessary memory-barriers
> for us.
> + * Note: wake_up_interruptible() performs any necessary memory-
> barriers for us.
> */
> static void hidp_session_terminate(struct hidp_session *session)
> {
> atomic_inc(&session->terminate);
> - wake_up_process(session->task);
> + wake_up_interruptible(&hidp_session_wq);
> }
>
> /*
> @@ -1180,7 +1181,9 @@ static void hidp_session_run(struct
> hidp_session *session)
> struct sock *ctrl_sk = session->ctrl_sock->sk;
> struct sock *intr_sk = session->intr_sock->sk;
> struct sk_buff *skb;
> + DEFINE_WAIT_FUNC(wait, woken_wake_function);
>
> + add_wait_queue(&hidp_session_wq, &wait);
> for (;;) {
> /*
> * This thread can be woken up two ways:
> @@ -1188,12 +1191,10 @@ static void hidp_session_run(struct
> hidp_session *session)
> * session->terminate flag and wakes this thread
> up.
> * - Via modifying the socket state of
> ctrl/intr_sock. This
> * thread is woken up by ->sk_state_changed().
> - *
> - * Note: set_current_state() performs any necessary
> - * memory-barriers for us.
> */
> - set_current_state(TASK_INTERRUPTIBLE);
>
> + /* Ensure session->terminate is updated */
> + smp_mb__before_atomic();
> if (atomic_read(&session->terminate))
> break;
>
> @@ -1227,11 +1228,22 @@ static void hidp_session_run(struct
> hidp_session *session)
> hidp_process_transmit(session, &session-
> >ctrl_transmit,
> session->ctrl_sock);
>
> - schedule();
> + wait_woken(&wait, TASK_INTERRUPTIBLE,
> MAX_SCHEDULE_TIMEOUT);
> }
> + remove_wait_queue(&hidp_session_wq, &wait);
>
> atomic_inc(&session->terminate);
> - set_current_state(TASK_RUNNING);
> +
> + /* Ensure session->terminate is updated */
> + smp_mb__after_atomic();
> +}
> +
> +static int hidp_session_wake_function(wait_queue_t *wait,
> + unsigned int mode,
> + int sync, void *key)
> +{
> + wake_up_interruptible(&hidp_session_wq);
> + return false;
> }
>
> /*
> @@ -1244,7 +1256,8 @@ static void hidp_session_run(struct
> hidp_session *session)
> static int hidp_session_thread(void *arg)
> {
> struct hidp_session *session = arg;
> - wait_queue_t ctrl_wait, intr_wait;
> + DEFINE_WAIT_FUNC(ctrl_wait, hidp_session_wake_function);
> + DEFINE_WAIT_FUNC(intr_wait, hidp_session_wake_function);
>
> BT_DBG("session %p", session);
>
> @@ -1254,8 +1267,6 @@ static int hidp_session_thread(void *arg)
> set_user_nice(current, -15);
> hidp_set_timer(session);
>
> - init_waitqueue_entry(&ctrl_wait, current);
> - init_waitqueue_entry(&intr_wait, current);
> add_wait_queue(sk_sleep(session->ctrl_sock->sk),
> &ctrl_wait);
> add_wait_queue(sk_sleep(session->intr_sock->sk),
> &intr_wait);
> /* This memory barrier is paired with wq_has_sleeper(). See
On Tue, 2017-02-14 at 08:55 +0800, Jeffy Chen wrote:
> It looks like cmtp_session has same pattern as the issue reported in
> old rfcomm:
>
> while (1) {
> set_current_state(TASK_INTERRUPTIBLE);
> if (condition)
> break;
> // may call might_sleep here
> schedule();
> }
> __set_current_state(TASK_RUNNING);
>
> Which fixed at:
> dfb2fae Bluetooth: Fix nested sleeps
>
> So let's fix it at the same way, also follow the suggestion of:
> https://lwn.net/Articles/628628/
>
> Signed-off-by: Jeffy Chen <[email protected]>
> Reviewed-by: Brian Norris <[email protected]>
> Remove unnecessary memory barrier before wake_up_* functions.
Reviewed-by: AL Yu-Chen Cho <[email protected]>
>
> ---
>
> Changes in v3:
> Add brian's Reviewed-by.
>
> Changes in v2: None
>
> net/bluetooth/cmtp/core.c | 17 ++++++++++-------
> 1 file changed, 10 insertions(+), 7 deletions(-)
>
> diff --git a/net/bluetooth/cmtp/core.c b/net/bluetooth/cmtp/core.c
> index 9e59b66..1152ce3 100644
> --- a/net/bluetooth/cmtp/core.c
> +++ b/net/bluetooth/cmtp/core.c
> @@ -280,16 +280,16 @@ static int cmtp_session(void *arg)
> struct cmtp_session *session = arg;
> struct sock *sk = session->sock->sk;
> struct sk_buff *skb;
> - wait_queue_t wait;
> + DEFINE_WAIT_FUNC(wait, woken_wake_function);
>
> BT_DBG("session %p", session);
>
> set_user_nice(current, -15);
>
> - init_waitqueue_entry(&wait, current);
> add_wait_queue(sk_sleep(sk), &wait);
> while (1) {
> - set_current_state(TASK_INTERRUPTIBLE);
> + /* Ensure session->terminate is updated */
> + smp_mb__before_atomic();
>
> if (atomic_read(&session->terminate))
> break;
> @@ -306,9 +306,8 @@ static int cmtp_session(void *arg)
>
> cmtp_process_transmit(session);
>
> - schedule();
> + wait_woken(&wait, TASK_INTERRUPTIBLE,
> MAX_SCHEDULE_TIMEOUT);
> }
> - __set_current_state(TASK_RUNNING);
> remove_wait_queue(sk_sleep(sk), &wait);
>
> down_write(&cmtp_session_sem);
> @@ -393,7 +392,7 @@ int cmtp_add_connection(struct cmtp_connadd_req
> *req, struct socket *sock)
> err = cmtp_attach_device(session);
> if (err < 0) {
> atomic_inc(&session->terminate);
> - wake_up_process(session->task);
> + wake_up_interruptible(sk_sleep(session-
> >sock->sk));
> up_write(&cmtp_session_sem);
> return err;
> }
> @@ -431,7 +430,11 @@ int cmtp_del_connection(struct cmtp_conndel_req
> *req)
>
> /* Stop session thread */
> atomic_inc(&session->terminate);
> - wake_up_process(session->task);
> +
> + /* Ensure session->terminate is updated */
> + smp_mb__after_atomic();
> +
> + wake_up_interruptible(sk_sleep(session->sock->sk));
> } else
> err = -ENOENT;
>
On Tue, 2017-02-14 at 08:55 +0800, Jeffy Chen wrote:
> It looks like bnep_session has same pattern as the issue reported in
> old rfcomm:
>
> while (1) {
> set_current_state(TASK_INTERRUPTIBLE);
> if (condition)
> break;
> // may call might_sleep here
> schedule();
> }
> __set_current_state(TASK_RUNNING);
>
> Which fixed at:
> dfb2fae Bluetooth: Fix nested sleeps
>
> So let's fix it at the same way, also follow the suggestion of:
> https://lwn.net/Articles/628628/
>
> Signed-off-by: Jeffy Chen <[email protected]>
> Reviewed-by: Brian Norris <[email protected]>
Reviewed-by: AL Yu-Chen Cho <[email protected]>
> ---
>
> Changes in v3:
> Add brian's Reviewed-by.
>
> Changes in v2:
> Remove unnecessary memory barrier before wake_up_* functions.
>
> net/bluetooth/bnep/core.c | 11 +++++------
> 1 file changed, 5 insertions(+), 6 deletions(-)
>
> diff --git a/net/bluetooth/bnep/core.c b/net/bluetooth/bnep/core.c
> index fbf251f..4d6b94d 100644
> --- a/net/bluetooth/bnep/core.c
> +++ b/net/bluetooth/bnep/core.c
> @@ -484,16 +484,16 @@ static int bnep_session(void *arg)
> struct net_device *dev = s->dev;
> struct sock *sk = s->sock->sk;
> struct sk_buff *skb;
> - wait_queue_t wait;
> + DEFINE_WAIT_FUNC(wait, woken_wake_function);
>
> BT_DBG("");
>
> set_user_nice(current, -15);
>
> - init_waitqueue_entry(&wait, current);
> add_wait_queue(sk_sleep(sk), &wait);
> while (1) {
> - set_current_state(TASK_INTERRUPTIBLE);
> + /* Ensure session->terminate is updated */
> + smp_mb__before_atomic();
>
> if (atomic_read(&s->terminate))
> break;
> @@ -515,9 +515,8 @@ static int bnep_session(void *arg)
> break;
> netif_wake_queue(dev);
>
> - schedule();
> + wait_woken(&wait, TASK_INTERRUPTIBLE,
> MAX_SCHEDULE_TIMEOUT);
> }
> - __set_current_state(TASK_RUNNING);
> remove_wait_queue(sk_sleep(sk), &wait);
>
> /* Cleanup session */
> @@ -666,7 +665,7 @@ int bnep_del_connection(struct bnep_conndel_req
> *req)
> s = __bnep_get_session(req->dst);
> if (s) {
> atomic_inc(&s->terminate);
> - wake_up_process(s->task);
> + wake_up_interruptible(sk_sleep(s->sock->sk));
> } else
> err = -ENOENT;
>