mirror of
https://github.com/apache/nuttx.git
synced 2026-05-12 01:42:49 +08:00
ouyangxiangzhen
f1b355f118
This commit updated the comments. Signed-off-by: ouyangxiangzhen <ouyangxiangzhen@xiaomi.com>
118 lines
3.7 KiB
C
118 lines
3.7 KiB
C
/****************************************************************************
|
|
* sched/hrtimer/hrtimer_start.c
|
|
*
|
|
* SPDX-License-Identifier: Apache-2.0
|
|
*
|
|
* Licensed to the Apache Software Foundation (ASF) under one or more
|
|
* contributor license agreements. See the NOTICE file distributed with
|
|
* this work for additional information regarding copyright ownership. The
|
|
* ASF licenses this file to you under the Apache License, Version 2.0 (the
|
|
* "License"); you may not use this file except in compliance with the
|
|
* License. You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Included Files
|
|
****************************************************************************/
|
|
|
|
#include <nuttx/config.h>
|
|
#include <nuttx/arch.h>
|
|
#include <nuttx/clock.h>
|
|
#include <errno.h>
|
|
|
|
#include "hrtimer/hrtimer.h"
|
|
|
|
/****************************************************************************
|
|
* Public Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Name: hrtimer_start
|
|
*
|
|
* Description:
|
|
* Start a high-resolution timer to expire after a specified duration
|
|
* in nanoseconds, either as an absolute or relative time.
|
|
*
|
|
* Input Parameters:
|
|
* hrtimer - Pointer to the hrtimer structure.
|
|
* func - Expiration callback function.
|
|
* expired - Expiration time in nanoseconds. Interpretation
|
|
* depends on mode.
|
|
* mode - Timer mode (HRTIMER_MODE_ABS or HRTIMER_MODE_REL).
|
|
*
|
|
* Returned Value:
|
|
* OK (0) on success, or a negated errno value on failure.
|
|
*
|
|
* Assumptions/Notes:
|
|
* - This function disables interrupts briefly via spinlock to safely
|
|
* insert the timer into the container.
|
|
* - Absolute mode sets the timer to expire at the given absolute time.
|
|
* - Relative mode sets the timer to expire after 'ns'
|
|
* nanoseconds from the current time.
|
|
****************************************************************************/
|
|
|
|
int hrtimer_start(FAR hrtimer_t *hrtimer, hrtimer_entry_t func,
|
|
uint64_t expired,
|
|
enum hrtimer_mode_e mode)
|
|
{
|
|
uint64_t next_expired;
|
|
irqstate_t flags;
|
|
int ret = OK;
|
|
|
|
/* Compute absolute expiration time */
|
|
|
|
if (mode == HRTIMER_MODE_ABS)
|
|
{
|
|
next_expired = expired;
|
|
}
|
|
else
|
|
{
|
|
expired = expired <= HRTIMER_MAX_DELAY ? expired : HRTIMER_MAX_DELAY;
|
|
next_expired = clock_systime_nsec() + expired;
|
|
}
|
|
|
|
DEBUGASSERT(hrtimer != NULL);
|
|
|
|
/* Acquire the lock and seize the ownership of the hrtimer queue. */
|
|
|
|
flags = write_seqlock_irqsave(&g_hrtimer_lock);
|
|
|
|
/* Ensure no core can write the hrtimer. */
|
|
|
|
hrtimer_cancel_running(hrtimer);
|
|
|
|
if (hrtimer_is_armed(hrtimer))
|
|
{
|
|
hrtimer_remove(hrtimer);
|
|
}
|
|
|
|
hrtimer->func = func;
|
|
hrtimer->expired = next_expired;
|
|
|
|
/* Insert the timer into the hrtimer queue. */
|
|
|
|
hrtimer_insert(hrtimer);
|
|
|
|
/* If the inserted timer is now the earliest, start hardware timer */
|
|
|
|
if (hrtimer_is_first(hrtimer))
|
|
{
|
|
hrtimer_reprogram(hrtimer->expired);
|
|
}
|
|
|
|
/* Release the lock and give up the ownership of the hrtimer queue. */
|
|
|
|
write_sequnlock_irqrestore(&g_hrtimer_lock, flags);
|
|
|
|
return ret;
|
|
}
|