Based on an original patch by Robert Kaiser.
Signed-off-by: Grzegorz Milos <gm281@cam.ac.uk>
- to start it do the following in domain0 (assuming xend is running)
# xm create domain_config
-this starts the kernel and prints out a bunch of stuff and then every
-1000 timer interrupts the system time.
+this starts the kernel and prints out a bunch of stuff and then once
+every second the system time.
#define __SCHED_H__
#include <list.h>
+#include <time.h>
struct thread
{
unsigned long ip; /* Instruction pointer */
struct list_head thread_list;
u32 flags;
+ s_time_t wakeup_time;
};
void wake(struct thread *thread);
void block(struct thread *thread);
+void sleep(u32 millisecs);
#endif /* __SCHED_H__ */
* File: time.h
* Author: Rolf Neugebauer (neugebar@dcs.gla.ac.uk)
* Changes: Grzegorz Milos (gm281@cam.ac.uk)
+ * Robert Kaiser (kaiser@informatik.fh-wiesbaden.de)
*
- * Date: Jul 2003, changesJun 2005
+ * Date: Jul 2003, changes: Jun 2005, Sep 2006
*
* Environment: Xen Minimal OS
* Description: Time and timer functions
void init_time(void);
s_time_t get_s_time(void);
s_time_t get_v_time(void);
+u64 monotonic_clock(void);
void gettimeofday(struct timeval *tv);
-void block_domain(u32 millisecs);
+void block_domain(s_time_t until);
#endif /* _TIME_H_ */
*
* Copyright (c) 2002-2003, K A Fraser & R Neugebauer
* Copyright (c) 2005, Grzegorz Milos, Intel Research Cambridge
+ * Copyright (c) 2006, Robert Kaiser, FH Wiesbaden
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to
/* test_xenbus(); */
}
+void periodic_thread(void *p)
+{
+ struct timeval tv;
+ printk("Periodic thread started.\n");
+ for(;;)
+ {
+ gettimeofday(&tv);
+ printk("T(s=%ld us=%ld)\n", tv.tv_sec, tv.tv_usec);
+ sleep(1000);
+ }
+}
+
/* This should be overridden by the application we are linked against. */
__attribute__((weak)) int app_main(start_info_t *si)
{
printk("Dummy main: start_info=%p\n", si);
create_thread("xenbus_tester", xenbus_tester, si);
+ create_thread("periodic_thread", periodic_thread, si);
return 0;
}
*
* File: sched.c
* Author: Grzegorz Milos
- * Changes:
+ * Changes: Robert Kaiser
*
* Date: Aug 2005
*
printk("\n");
}
+/* Find the time when the next timeout expires. If this is more than
+ 10 seconds from now, return 10 seconds from now. */
+static s_time_t blocking_time(void)
+{
+ struct thread *thread;
+ struct list_head *iterator;
+ s_time_t min_wakeup_time;
+ unsigned long flags;
+ local_irq_save(flags);
+ /* default-block the domain for 10 seconds: */
+ min_wakeup_time = NOW() + SECONDS(10);
+
+ /* Thread list needs to be protected */
+ list_for_each(iterator, &idle_thread->thread_list)
+ {
+ thread = list_entry(iterator, struct thread, thread_list);
+ if(!is_runnable(thread) && thread->wakeup_time != 0LL)
+ {
+ if(thread->wakeup_time < min_wakeup_time)
+ {
+ min_wakeup_time = thread->wakeup_time;
+ }
+ }
+ }
+ local_irq_restore(flags);
+ return(min_wakeup_time);
+}
+
+/* Wake up all threads with expired timeouts. */
+static void wake_expired(void)
+{
+ struct thread *thread;
+ struct list_head *iterator;
+ s_time_t now = NOW();
+ unsigned long flags;
+ local_irq_save(flags);
+ /* Thread list needs to be protected */
+ list_for_each(iterator, &idle_thread->thread_list)
+ {
+ thread = list_entry(iterator, struct thread, thread_list);
+ if(!is_runnable(thread) && thread->wakeup_time != 0LL)
+ {
+ if(thread->wakeup_time <= now)
+ wake(thread);
+ }
+ }
+ local_irq_restore(flags);
+}
void schedule(void)
{
stack_push(thread, (unsigned long) data);
thread->ip = (unsigned long) thread_starter;
- /* Not runable, not exited */
+ /* Not runable, not exited, not sleeping */
thread->flags = 0;
+ thread->wakeup_time = 0LL;
set_runnable(thread);
local_irq_save(flags);
if(idle_thread != NULL) {
void block(struct thread *thread)
{
+ thread->wakeup_time = 0LL;
clear_runnable(thread);
}
+void sleep(u32 millisecs)
+{
+ struct thread *thread = get_current();
+ thread->wakeup_time = NOW() + MILLISECS(millisecs);
+ clear_runnable(thread);
+ schedule();
+}
+
void wake(struct thread *thread)
{
+ thread->wakeup_time = 0LL;
set_runnable(thread);
}
void idle_thread_fn(void *unused)
{
+ s_time_t until;
for(;;)
{
schedule();
- block_domain(10000);
+ /* block until the next timeout expires, or for 10 secs, whichever comes first */
+ until = blocking_time();
+ block_domain(until);
+ wake_expired();
}
}
"push %1\n\t"
"ret"
:"=m" (idle_thread->sp)
- :"m" (idle_thread->ip));
+ :"m" (idle_thread->ip));
#endif
}
* (C) 2003 - Rolf Neugebauer - Intel Research Cambridge
* (C) 2002-2003 - Keir Fraser - University of Cambridge
* (C) 2005 - Grzegorz Milos - Intel Research Cambridge
+ * (C) 2006 - Robert Kaiser - FH Wiesbaden
****************************************************************************
*
* File: time.c
}
-static void print_current_time(void)
-{
- struct timeval tv;
-
- gettimeofday(&tv);
- printk("T(s=%ld us=%ld)\n", tv.tv_sec, tv.tv_usec);
-}
-
-
-void block_domain(u32 millisecs)
+void block_domain(s_time_t until)
{
struct timeval tv;
gettimeofday(&tv);
- HYPERVISOR_set_timer_op(monotonic_clock() + 1000000LL * (s64) millisecs);
- HYPERVISOR_sched_op(SCHEDOP_block, 0);
+ if(monotonic_clock() < until)
+ {
+ HYPERVISOR_set_timer_op(until);
+ HYPERVISOR_sched_op(SCHEDOP_block, 0);
+ }
}
*/
static void timer_handler(evtchn_port_t ev, struct pt_regs *regs, void *ign)
{
- static int i;
-
get_time_values_from_xen();
update_wallclock();
- i++;
- if (i >= 1000) {
- print_current_time();
- i = 0;
- }
}