diff options
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/serial/8250/8250.c | 27 | ||||
| -rw-r--r-- | drivers/tty/serial/cpm_uart/cpm_uart_core.c | 2 | ||||
| -rw-r--r-- | drivers/tty/serial/omap-serial.c | 12 | ||||
| -rw-r--r-- | drivers/tty/sysrq.c | 23 | ||||
| -rw-r--r-- | drivers/tty/tty_buffer.c | 4 | ||||
| -rw-r--r-- | drivers/tty/tty_ldisc.c | 4 |
6 files changed, 50 insertions, 22 deletions
diff --git a/drivers/tty/serial/8250/8250.c b/drivers/tty/serial/8250/8250.c index 5c27f7e6c9f1..ff9c051ca980 100644 --- a/drivers/tty/serial/8250/8250.c +++ b/drivers/tty/serial/8250/8250.c @@ -38,6 +38,7 @@ #include <linux/nmi.h> #include <linux/mutex.h> #include <linux/slab.h> +#include <linux/kdb.h> #ifdef CONFIG_SPARC #include <linux/sunserialcore.h> #endif @@ -80,7 +81,16 @@ static unsigned int skip_txen_test; /* force skip of txen test at init time */ #define DEBUG_INTR(fmt...) do { } while (0) #endif -#define PASS_LIMIT 512 +/* + * On -rt we can have a more delays, and legitimately + * so - so don't drop work spuriously and spam the + * syslog: + */ +#ifdef CONFIG_PREEMPT_RT_FULL +# define PASS_LIMIT 1000000 +#else +# define PASS_LIMIT 512 +#endif #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE) @@ -2807,14 +2817,10 @@ serial8250_console_write(struct console *co, const char *s, unsigned int count) touch_nmi_watchdog(); - local_irq_save(flags); - if (port->sysrq) { - /* serial8250_handle_irq() already took the lock */ - locked = 0; - } else if (oops_in_progress) { - locked = spin_trylock(&port->lock); - } else - spin_lock(&port->lock); + if (port->sysrq || oops_in_progress || in_kdb_printk()) + locked = spin_trylock_irqsave(&port->lock, flags); + else + spin_lock_irqsave(&port->lock, flags); /* * First save the IER then disable the interrupts @@ -2846,8 +2852,7 @@ serial8250_console_write(struct console *co, const char *s, unsigned int count) serial8250_modem_status(up); if (locked) - spin_unlock(&port->lock); - local_irq_restore(flags); + spin_unlock_irqrestore(&port->lock, flags); } static int __init serial8250_console_setup(struct console *co, char *options) diff --git a/drivers/tty/serial/cpm_uart/cpm_uart_core.c b/drivers/tty/serial/cpm_uart/cpm_uart_core.c index b418947b7107..a8b05594e468 100644 --- a/drivers/tty/serial/cpm_uart/cpm_uart_core.c +++ b/drivers/tty/serial/cpm_uart/cpm_uart_core.c @@ -1226,7 +1226,7 @@ static void cpm_uart_console_write(struct console *co, const char *s, { struct uart_cpm_port *pinfo = &cpm_uart_ports[co->index]; unsigned long flags; - int nolock = oops_in_progress; + int nolock = oops_in_progress || sysrq_in_progress; if (unlikely(nolock)) { local_irq_save(flags); diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c index d00b38eb268e..f6974929c5bb 100644 --- a/drivers/tty/serial/omap-serial.c +++ b/drivers/tty/serial/omap-serial.c @@ -1064,13 +1064,10 @@ serial_omap_console_write(struct console *co, const char *s, pm_runtime_get_sync(&up->pdev->dev); - local_irq_save(flags); - if (up->port.sysrq) - locked = 0; - else if (oops_in_progress) - locked = spin_trylock(&up->port.lock); + if (up->port.sysrq || oops_in_progress) + locked = spin_trylock_irqsave(&up->port.lock, flags); else - spin_lock(&up->port.lock); + spin_lock_irqsave(&up->port.lock, flags); /* * First save the IER then disable the interrupts @@ -1099,8 +1096,7 @@ serial_omap_console_write(struct console *co, const char *s, pm_runtime_mark_last_busy(&up->pdev->dev); pm_runtime_put_autosuspend(&up->pdev->dev); if (locked) - spin_unlock(&up->port.lock); - local_irq_restore(flags); + spin_unlock_irqrestore(&up->port.lock, flags); } static int __init diff --git a/drivers/tty/sysrq.c b/drivers/tty/sysrq.c index 05728894a88c..b2141163ca36 100644 --- a/drivers/tty/sysrq.c +++ b/drivers/tty/sysrq.c @@ -495,6 +495,23 @@ static void __sysrq_put_key_op(int key, struct sysrq_key_op *op_p) sysrq_key_table[i] = op_p; } +#ifdef CONFIG_MAGIC_SYSRQ_FORCE_PRINTK + +int sysrq_in_progress; + +static void set_sysrq_in_progress(int value) +{ + sysrq_in_progress = value; +} + +#else + +static void set_sysrq_in_progress(int value) +{ +} + +#endif + void __handle_sysrq(int key, bool check_mask) { struct sysrq_key_op *op_p; @@ -503,6 +520,9 @@ void __handle_sysrq(int key, bool check_mask) unsigned long flags; spin_lock_irqsave(&sysrq_key_table_lock, flags); + + set_sysrq_in_progress(1); + /* * Raise the apparent loglevel to maximum so that the sysrq header * is shown to provide the user with positive feedback. We do not @@ -544,6 +564,9 @@ void __handle_sysrq(int key, bool check_mask) printk("\n"); console_loglevel = orig_log_level; } + + set_sysrq_in_progress(0); + spin_unlock_irqrestore(&sysrq_key_table_lock, flags); } diff --git a/drivers/tty/tty_buffer.c b/drivers/tty/tty_buffer.c index 6c9b7cd6778a..a56c2231fed3 100644 --- a/drivers/tty/tty_buffer.c +++ b/drivers/tty/tty_buffer.c @@ -493,10 +493,14 @@ void tty_flip_buffer_push(struct tty_struct *tty) tty->buf.tail->commit = tty->buf.tail->used; spin_unlock_irqrestore(&tty->buf.lock, flags); +#ifndef CONFIG_PREEMPT_RT_FULL if (tty->low_latency) flush_to_ldisc(&tty->buf.work); else schedule_work(&tty->buf.work); +#else + flush_to_ldisc(&tty->buf.work); +#endif } EXPORT_SYMBOL(tty_flip_buffer_push); diff --git a/drivers/tty/tty_ldisc.c b/drivers/tty/tty_ldisc.c index 24b95db75d84..7894759ce77c 100644 --- a/drivers/tty/tty_ldisc.c +++ b/drivers/tty/tty_ldisc.c @@ -53,7 +53,7 @@ static void put_ldisc(struct tty_ldisc *ld) * We really want an "atomic_dec_and_lock_irqsave()", * but we don't have it, so this does it by hand. */ - local_irq_save(flags); + local_irq_save_nort(flags); if (atomic_dec_and_lock(&ld->users, &tty_ldisc_lock)) { struct tty_ldisc_ops *ldo = ld->ops; @@ -64,7 +64,7 @@ static void put_ldisc(struct tty_ldisc *ld) kfree(ld); return; } - local_irq_restore(flags); + local_irq_restore_nort(flags); wake_up(&tty_ldisc_idle); } |