global.c File Reference

Globally Required Stuff. More...

#include <l4/lock/lock.h>
#include <l4/dde_linux/dde.h>
#include <asm/system.h>
#include <stdlib.h>
#include "__config.h"
#include "internal.h"
#include <linux/spinlock.h>
#include <asm/delay.h>

Go to the source code of this file.

Synchronization
Linux kernel synchronization is sometimes based on cli()/sti() pairs. As discussed in "Taming Linux" simply disabling Interrupts via cli and sti assembly statements is unacceptable in DROPS. The DDE uses the same lock based scheme as a tamed L4Linux server.
void	__global_cli ()
	Global CLear Interrupt flag.
void	__global_sti ()
	Global SeT Interrupt flag.
unsigned long	__global_save_flags ()
	Global save flags.
void	__global_restore_flags (unsigned long flags)
	Global restore flags.
l4lock_t	irq_lock = L4LOCK_UNLOCKED_INITIALIZER
	Interrupt lock.
Miscellaneous
int	get_option (char **str, int *pint)
	Parse integer from an option string.
char *	get_options (char *str, int nints, int *ints)
	Parse a string into a list of integers.
void	udelay (unsigned long usecs)
	Delay some usecs.
int	l4dde_driver_classes_init (void)
	Dummy for DDE2.6.
spinlock_cacheline_t	kernel_flag_cacheline = {SPIN_LOCK_UNLOCKED}
	BIG kernel lock.

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Detailed Description

Globally Required Stuff.

Date:

08/28/2003

Author:

Christian Helmuth <ch12@os.inf.tu-dresden.de>

Definition in file global.c.

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Function Documentation

void __global_cli (   )

Global CLear Interrupt flag. Acquire irq_lock. Do not grab it twice! Definition at line 46 of file global.c. References irq_lock. Referenced by __global_restore_flags().

void __global_restore_flags (  unsigned long  flags  )

Global restore flags. Parameters: flags  indicates action It restores irq_lock state. See also: __global_save_flags Definition at line 87 of file global.c. References __global_cli(), __global_sti(), and DEBUG_MSG.

unsigned long __global_save_flags (   )

Global save flags. Returns: flags indicating action on __global_restore_flags(flag) 0 - global cli 1 - global sti 2 - local cli 3 - local sti It is used to save the current irq_lock state. See also: __global_restore_flags Definition at line 73 of file global.c. References irq_lock.

void __global_sti (   )

Global SeT Interrupt flag. Release irq_lock. Definition at line 56 of file global.c. References irq_lock. Referenced by __global_restore_flags().

int get_option (  char **  str, int *  pint )

Parse integer from an option string. (from lib/cmdline.c) Definition at line 110 of file global.c. Referenced by get_options().

char* get_options (  char *  str, int  nints, int *  ints )

Parse a string into a list of integers. (from lib/cmdline.c) Definition at line 131 of file global.c. References get_option().

void udelay (  unsigned long  usecs  )

Delay some usecs. Todo: consider l4_busy_wait_us() for short delays Definition at line 159 of file global.c.

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