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intel_fb: remove schedule_timeout wrap

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Issue #4540
This commit is contained in:
Alexander Boettcher
2022-06-16 14:57:15 +02:00
committed by Christian Helmuth
parent 9ecbe51e34
commit 7b4556e546
4 changed files with 0 additions and 146 deletions
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2
repos/dde_linux/src/include/lx_emul/time.h
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@ -28,8 +28,6 @@ unsigned long long lx_emul_time_counter(void);
void lx_emul_time_handle(void);
void lx_emul_force_jiffies_update(void);
#ifdef __cplusplus
}
#endif

104
repos/dde_linux/src/lib/lx_emul/clocksource.c
View File

@ -131,107 +131,3 @@ void lx_emul_register_of_clk_initcall(char const *compat, void *fn)
count++;
}
/*
* private kernel/time header needed for internal functions
* used in lx_emul_force_jiffies_update
*/
#include <../kernel/time/tick-internal.h>
/*
* The functions lx_emul_force_jiffies_update, lx_clockevents_program_event
* and lx_clockevents_program_event implemented here are stripped down
* versions of the Linux internal time handling code, when clock is used in
* periodic mode.
*
* Normally time proceeds due to
* -> lx_emul/shadow/kernel/sched/core.c calls lx_emul_time_handle()
* -> repos/dde_linux/src/lib/lx_emul/clocksource.c:lx_emul_time_handle() calls
* -> dde_clock_event_device->event_handle() == tick_handle_periodic()
* -> kernel/time/tick-common.c -> tick_handle_periodic()
* -> kernel/time/clockevents.c -> clockevents_program_event()
* -> which fast forwards jiffies in a loop until it matches wall clock
*
* lx_emul_force_jiffies_update can be used to update jiffies to current,
* before invoking schedule_timeout(), which expects current jiffies values.
* Without current jiffies, the programmed timeouts are too short, which leads
* to timeouts firing too early.
*/
/**
* based on kernel/time/clockevents.c clockevents_program_event()
*/
static int lx_clockevents_program_event(struct clock_event_device *dev,
ktime_t expires)
{
int64_t delta;
if (WARN_ON_ONCE(expires < 0))
return 0;
dev->next_event = expires;
if (clockevent_state_shutdown(dev))
return 0;
if (dev->features & CLOCK_EVT_FEAT_KTIME)
return 0;
delta = ktime_to_ns(ktime_sub(expires, ktime_get()));
if (delta <= 0) {
int res = -ETIME;
return res;
}
return 0;
}
/**
* based on kernel/time/tick-common.c tick_handle_periodic()
*/
void lx_emul_force_jiffies_update(void)
{
struct clock_event_device *dev = dde_clock_event_device;
ktime_t next = dev->next_event;
#if defined(CONFIG_HIGH_RES_TIMERS) || defined(CONFIG_NO_HZ_COMMON)
/*
* The cpu might have transitioned to HIGHRES or NOHZ mode via
* update_process_times() -> run_local_timers() ->
* hrtimer_run_queues().
*/
if (dev->event_handler != tick_handle_periodic)
return;
#endif
if (!clockevent_state_oneshot(dev))
return;
for (;;) {
/*
* Setup the next period for devices, which do not have
* periodic mode:
*/
next = ktime_add_ns(next, TICK_NSEC);
if (!lx_clockevents_program_event(dev, next))
return;
/*
* Have to be careful here. If we're in oneshot mode,
* before we call tick_periodic() in a loop, we need
* to be sure we're using a real hardware clocksource.
* Otherwise we could get trapped in an infinite
* loop, as the tick_periodic() increments jiffies,
* which then will increment time, possibly causing
* the loop to trigger again and again.
*/
if (timekeeping_valid_for_hres()) {
do_timer(1); /* tick_periodic(cpu); */
}
}
}