2017-03-22 17:15:02

by Lionel Debieve

Subject: [PATCH 1/1] tty: serial: st-asc: Make the locking RT aware

The lock is a sleeping lock and local_irq_save() is not the
standard implementation now. Working for both -RT and non
RT.

Signed-off-by: Lionel Debieve <[email protected]>
---
drivers/tty/serial/st-asc.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/tty/serial/st-asc.c b/drivers/tty/serial/st-asc.c
index c334bcc..4889396 100644
--- a/drivers/tty/serial/st-asc.c
+++ b/drivers/tty/serial/st-asc.c
@@ -887,13 +887,12 @@ static void asc_console_write(struct console *co, const char *s, unsigned count)
int locked = 1;
u32 intenable;

- local_irq_save(flags);
if (port->sysrq)
locked = 0; /* asc_interrupt has already claimed the lock */
else if (oops_in_progress)
- locked = spin_trylock(&port->lock);
+ locked = spin_trylock_irqsave(&port->lock, flags);
else
- spin_lock(&port->lock);
+ spin_lock_irqsave(&port->lock, flags);

/*
* Disable interrupts so we don't get the IRQ line bouncing
@@ -911,8 +910,7 @@ static void asc_console_write(struct console *co, const char *s, unsigned count)
asc_out(port, ASC_INTEN, intenable);

if (locked)
- spin_unlock(&port->lock);
- local_irq_restore(flags);
+ spin_unlock_irqrestore(&port->lock, flags);
}

static int asc_console_setup(struct console *co, char *options)
--
2.7.4

2017-03-23 07:57:13

by Patrice CHOTARD

Subject: Re: [PATCH 1/1] tty: serial: st-asc: Make the locking RT aware

Hi Lionel

On 03/22/2017 06:12 PM, Lionel Debieve wrote:
> The lock is a sleeping lock and local_irq_save() is not the
> standard implementation now. Working for both -RT and non
> RT.
>
> Signed-off-by: Lionel Debieve <[email protected]>

Acked-by: Patrice Chotard <[email protected]>


> ---
> drivers/tty/serial/st-asc.c | 8 +++-----
> 1 file changed, 3 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/tty/serial/st-asc.c b/drivers/tty/serial/st-asc.c
> index c334bcc..4889396 100644
> --- a/drivers/tty/serial/st-asc.c
> +++ b/drivers/tty/serial/st-asc.c
> @@ -887,13 +887,12 @@ static void asc_console_write(struct console *co, const char *s, unsigned count)
> int locked = 1;
> u32 intenable;
>
> - local_irq_save(flags);
> if (port->sysrq)
> locked = 0; /* asc_interrupt has already claimed the lock */
> else if (oops_in_progress)
> - locked = spin_trylock(&port->lock);
> + locked = spin_trylock_irqsave(&port->lock, flags);
> else
> - spin_lock(&port->lock);
> + spin_lock_irqsave(&port->lock, flags);
>
> /*
> * Disable interrupts so we don't get the IRQ line bouncing
> @@ -911,8 +910,7 @@ static void asc_console_write(struct console *co, const char *s, unsigned count)
> asc_out(port, ASC_INTEN, intenable);
>
> if (locked)
> - spin_unlock(&port->lock);
> - local_irq_restore(flags);
> + spin_unlock_irqrestore(&port->lock, flags);
> }
>
> static int asc_console_setup(struct console *co, char *options)
>

2017-03-29 16:10:51

by Sebastian Andrzej Siewior

Subject: Re: [PATCH 1/1] tty: serial: st-asc: Make the locking RT aware

On 2017-03-22 18:12:31 [+0100], Lionel Debieve wrote:
> The lock is a sleeping lock and local_irq_save() is not the
> standard implementation now. Working for both -RT and non
> RT.
>
> Signed-off-by: Lionel Debieve <[email protected]>

Acked-by: Sebastian Andrzej Siewior <[email protected]>

This is how serial8250_console_write() looks upstream, too.

Sebastian