From d6c53c0e9bd0a83f9f9ddbc9fd80141a54d83896 Mon Sep 17 00:00:00 2001 From: Jiri Slaby Date: Thu, 3 Jan 2013 15:53:05 +0100 Subject: TTY: move low_latency to tty_port One point is to have less places where we actually need tty pointer. The other is that low_latency is bound to buffer processing and buffers are now in tty_port. So it makes sense to move low_latency to tty_port too. Signed-off-by: Jiri Slaby Signed-off-by: Greg Kroah-Hartman --- include/linux/tty.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'include/linux/tty.h') diff --git a/include/linux/tty.h b/include/linux/tty.h index 8db1b569c37a..f16a47a13a09 100644 --- a/include/linux/tty.h +++ b/include/linux/tty.h @@ -202,7 +202,8 @@ struct tty_port { unsigned long iflags; /* TTYP_ internal flags */ #define TTYP_FLUSHING 1 /* Flushing to ldisc in progress */ #define TTYP_FLUSHPENDING 2 /* Queued buffer flush pending */ - unsigned char console:1; /* port is a console */ + unsigned char console:1, /* port is a console */ + low_latency:1; /* direct buffer flush */ struct mutex mutex; /* Locking */ struct mutex buf_mutex; /* Buffer alloc lock */ unsigned char *xmit_buf; /* Optional buffer */ @@ -254,7 +255,7 @@ struct tty_struct { int count; struct winsize winsize; /* termios mutex */ unsigned char stopped:1, hw_stopped:1, flow_stopped:1, packet:1; - unsigned char low_latency:1, warned:1; + unsigned char warned:1; unsigned char ctrl_status; /* ctrl_lock */ unsigned int receive_room; /* Bytes free for queue */ -- cgit v1.2.2 From 2e124b4a390ca85325fae75764bef92f0547fa25 Mon Sep 17 00:00:00 2001 From: Jiri Slaby Date: Thu, 3 Jan 2013 15:53:06 +0100 Subject: TTY: switch tty_flip_buffer_push Now, we start converting tty buffer functions to actually use tty_port. This will allow us to get rid of the need of tty in many call sites. Only tty_port will needed and hence no more tty_port_tty_get in those paths. Now, the one where most of tty_port_tty_get gets removed: tty_flip_buffer_push. IOW we also closed all the races in drivers not using tty_port_tty_get at all yet. Also we move tty_flip_buffer_push declaration from include/linux/tty.h to include/linux/tty_flip.h to all others while we are changing it anyway. Signed-off-by: Jiri Slaby Signed-off-by: Greg Kroah-Hartman --- include/linux/tty.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include/linux/tty.h') diff --git a/include/linux/tty.h b/include/linux/tty.h index f16a47a13a09..f89acd1ed6d3 100644 --- a/include/linux/tty.h +++ b/include/linux/tty.h @@ -387,7 +387,6 @@ extern void do_SAK(struct tty_struct *tty); extern void __do_SAK(struct tty_struct *tty); extern void disassociate_ctty(int priv); extern void no_tty(void); -extern void tty_flip_buffer_push(struct tty_struct *tty); extern void tty_flush_to_ldisc(struct tty_struct *tty); extern void tty_buffer_free_all(struct tty_port *port); extern void tty_buffer_flush(struct tty_struct *tty); -- cgit v1.2.2 From 4f73bc4dd3e8563ef4109f293a092820dff66d92 Mon Sep 17 00:00:00 2001 From: Joe Millenbach Date: Thu, 17 Jan 2013 22:44:22 -0800 Subject: tty: Added a CONFIG_TTY option to allow removal of TTY The option allows you to remove TTY and compile without errors. This saves space on systems that won't support TTY interfaces anyway. bloat-o-meter output is below. The bulk of this patch consists of Kconfig changes adding "depends on TTY" to various serial devices and similar drivers that require the TTY layer. Ideally, these dependencies would occur on a common intermediate symbol such as SERIO, but most drivers "select SERIO" rather than "depends on SERIO", and "select" does not respect dependencies. bloat-o-meter output comparing our previous minimal to new minimal by removing TTY. The list is filtered to not show removed entries with awk '$3 != "-"' as the list was very long. add/remove: 0/226 grow/shrink: 2/14 up/down: 6/-35356 (-35350) function old new delta chr_dev_init 166 170 +4 allow_signal 80 82 +2 static.__warned 143 142 -1 disallow_signal 63 62 -1 __set_special_pids 95 94 -1 unregister_console 126 121 -5 start_kernel 546 541 -5 register_console 593 588 -5 copy_from_user 45 40 -5 sys_setsid 128 120 -8 sys_vhangup 32 19 -13 do_exit 1543 1526 -17 bitmap_zero 60 40 -20 arch_local_irq_save 137 117 -20 release_task 674 652 -22 static.spin_unlock_irqrestore 308 260 -48 Signed-off-by: Joe Millenbach Reviewed-by: Jamey Sharp Reviewed-by: Josh Triplett Signed-off-by: Greg Kroah-Hartman --- include/linux/tty.h | 44 +++++++++++++++++++++++++++++++++----------- 1 file changed, 33 insertions(+), 11 deletions(-) (limited to 'include/linux/tty.h') diff --git a/include/linux/tty.h b/include/linux/tty.h index f89acd1ed6d3..c75d886b0307 100644 --- a/include/linux/tty.h +++ b/include/linux/tty.h @@ -318,11 +318,43 @@ struct tty_file_private { #define TTY_WRITE_FLUSH(tty) tty_write_flush((tty)) +#ifdef CONFIG_TTY +extern void console_init(void); +extern void tty_kref_put(struct tty_struct *tty); +extern struct pid *tty_get_pgrp(struct tty_struct *tty); +extern void tty_vhangup_self(void); +extern void disassociate_ctty(int priv); +extern dev_t tty_devnum(struct tty_struct *tty); +extern void proc_clear_tty(struct task_struct *p); +extern struct tty_struct *get_current_tty(void); +/* tty_io.c */ +extern int __init tty_init(void); +#else +static inline void console_init(void) +{ } +static inline void tty_kref_put(struct tty_struct *tty) +{ } +static inline struct pid *tty_get_pgrp(struct tty_struct *tty) +{ return NULL; } +static inline void tty_vhangup_self(void) +{ } +static inline void disassociate_ctty(int priv) +{ } +static inline dev_t tty_devnum(struct tty_struct *tty) +{ return 0; } +static inline void proc_clear_tty(struct task_struct *p) +{ } +static inline struct tty_struct *get_current_tty(void) +{ return NULL; } +/* tty_io.c */ +static inline int __init tty_init(void) +{ return 0; } +#endif + extern void tty_write_flush(struct tty_struct *); extern struct ktermios tty_std_termios; -extern void console_init(void); extern int vcs_init(void); extern struct class *tty_class; @@ -342,7 +374,6 @@ static inline struct tty_struct *tty_kref_get(struct tty_struct *tty) kref_get(&tty->kref); return tty; } -extern void tty_kref_put(struct tty_struct *tty); extern int tty_paranoia_check(struct tty_struct *tty, struct inode *inode, const char *routine); @@ -374,18 +405,15 @@ extern void tty_driver_remove_tty(struct tty_driver *driver, struct tty_struct *tty); extern void tty_free_termios(struct tty_struct *tty); extern int is_current_pgrp_orphaned(void); -extern struct pid *tty_get_pgrp(struct tty_struct *tty); extern int is_ignored(int sig); extern int tty_signal(int sig, struct tty_struct *tty); extern void tty_hangup(struct tty_struct *tty); extern void tty_vhangup(struct tty_struct *tty); extern void tty_vhangup_locked(struct tty_struct *tty); -extern void tty_vhangup_self(void); extern void tty_unhangup(struct file *filp); extern int tty_hung_up_p(struct file *filp); extern void do_SAK(struct tty_struct *tty); extern void __do_SAK(struct tty_struct *tty); -extern void disassociate_ctty(int priv); extern void no_tty(void); extern void tty_flush_to_ldisc(struct tty_struct *tty); extern void tty_buffer_free_all(struct tty_port *port); @@ -415,9 +443,6 @@ extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg); extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file, unsigned int cmd, unsigned long arg); extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg); -extern dev_t tty_devnum(struct tty_struct *tty); -extern void proc_clear_tty(struct task_struct *p); -extern struct tty_struct *get_current_tty(void); extern void tty_default_fops(struct file_operations *fops); extern struct tty_struct *alloc_tty_struct(void); extern int tty_alloc_file(struct file *file); @@ -543,9 +568,6 @@ static inline int tty_audit_push_task(struct task_struct *tsk, } #endif -/* tty_io.c */ -extern int __init tty_init(void); - /* tty_ioctl.c */ extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file, unsigned int cmd, unsigned long arg); -- cgit v1.2.2