diff options
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/serial/8250.c | 29 | ||||
| -rw-r--r-- | drivers/tty/serial/cpm_uart/cpm_uart_core.c | 2 | ||||
| -rw-r--r-- | drivers/tty/serial/omap-serial.c | 8 | ||||
| -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, 52 insertions, 18 deletions
diff --git a/drivers/tty/serial/8250.c b/drivers/tty/serial/8250.c index eeadf1b8e093..0596a359d30c 100644 --- a/drivers/tty/serial/8250.c +++ b/drivers/tty/serial/8250.c @@ -38,6 +38,7 @@ #include <linux/nmi.h> #include <linux/mutex.h> #include <linux/slab.h> +#include <linux/kdb.h> #include <asm/io.h> #include <asm/irq.h> @@ -81,7 +82,16 @@ 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) @@ -2846,14 +2856,14 @@ serial8250_console_write(struct console *co, const char *s, unsigned int count) touch_nmi_watchdog(); - local_irq_save(flags); - if (up->port.sysrq) { - /* serial8250_handle_port() already took the lock */ + if (unlikely(in_kdb_printk())) { locked = 0; - } else if (oops_in_progress) { - locked = spin_trylock(&up->port.lock); - } else - spin_lock(&up->port.lock); + } else { + if (up->port.sysrq || oops_in_progress) + locked = spin_trylock_irqsave(&up->port.lock, flags); + else + spin_lock_irqsave(&up->port.lock, flags); + } /* * First save the IER then disable the interrupts @@ -2885,8 +2895,7 @@ serial8250_console_write(struct console *co, const char *s, unsigned int count) check_modem_status(up); if (locked) - spin_unlock(&up->port.lock); - local_irq_restore(flags); + spin_unlock_irqrestore(&up->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 5e713d3ef1f4..93cdb92d1632 100644 --- a/drivers/tty/serial/omap-serial.c +++ b/drivers/tty/serial/omap-serial.c @@ -946,13 +946,12 @@ serial_omap_console_write(struct console *co, const char *s, unsigned int ier; int locked = 1; - local_irq_save(flags); if (up->port.sysrq) locked = 0; else if (oops_in_progress) - locked = spin_trylock(&up->port.lock); + 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 @@ -979,8 +978,7 @@ serial_omap_console_write(struct console *co, const char *s, check_modem_status(up); 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 43db715f1502..5219738ffd11 100644 --- a/drivers/tty/sysrq.c +++ b/drivers/tty/sysrq.c @@ -492,6 +492,23 @@ 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; @@ -500,6 +517,9 @@ 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 @@ -541,6 +561,9 @@ 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 8e0924f55446..820f7dc90061 100644 --- a/drivers/tty/tty_ldisc.c +++ b/drivers/tty/tty_ldisc.c @@ -71,7 +71,7 @@ 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; @@ -82,7 +82,7 @@ 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); } |