watchdogimpl.h

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/* SPDX-License-Identifier: BSD-2-Clause */
 
/*
 *  COPYRIGHT (c) 1989-2004.
 *  On-Line Applications Research Corporation (OAR).
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */
 
#ifndef _RTEMS_SCORE_WATCHDOGIMPL_H
#define _RTEMS_SCORE_WATCHDOGIMPL_H
 
#include <rtems/score/watchdog.h>
#include <rtems/score/watchdogticks.h>
#include <rtems/score/assert.h>
#include <rtems/score/isrlock.h>
#include <rtems/score/percpu.h>
#include <rtems/score/rbtreeimpl.h>
 
#include <sys/types.h>
#include <sys/timespec.h>
 
#ifdef __cplusplus
extern "C" {
#endif
 
typedef enum {
  WATCHDOG_SCHEDULED_BLACK,
 
  WATCHDOG_SCHEDULED_RED,
 
  WATCHDOG_INACTIVE,
 
  WATCHDOG_PENDING
} Watchdog_State;
 
#if defined(RTEMS_SMP)
  #define WATCHDOG_INITIALIZER( routine ) \
    { \
      { { { NULL, NULL, NULL, WATCHDOG_INACTIVE } } }, \
      &_Per_CPU_Information[ 0 ].per_cpu, \
      ( routine ), \
      0 \
    }
#else
  #define WATCHDOG_INITIALIZER( routine ) \
    { \
      { { { NULL, NULL, NULL, WATCHDOG_INACTIVE } } }, \
      ( routine ), \
      0 \
    }
#endif
 
static inline void _Watchdog_Header_initialize(
  Watchdog_Header *header
)
{
  _RBTree_Initialize_empty( &header->Watchdogs );
  header->first = NULL;
}
 
static inline Watchdog_Control *_Watchdog_Header_first(
  const Watchdog_Header *header
)
{
  return (Watchdog_Control *) header->first;
}
 
static inline void _Watchdog_Header_destroy(
  Watchdog_Header *header
)
{
  /* Do nothing */
  (void) header;
}
 
void _Watchdog_Tick( struct Per_CPU_Control *cpu );
 
static inline Watchdog_State _Watchdog_Get_state(
  const Watchdog_Control *the_watchdog
)
{
  return (Watchdog_State) RB_COLOR( &the_watchdog->Node.RBTree, Node );
}
 
static inline void _Watchdog_Set_state(
  Watchdog_Control *the_watchdog,
  Watchdog_State    state
)
{
  RB_COLOR( &the_watchdog->Node.RBTree, Node ) = state;
}
 
static inline Per_CPU_Control *_Watchdog_Get_CPU(
  const Watchdog_Control *the_watchdog
)
{
#if defined(RTEMS_SMP)
  return the_watchdog->cpu;
#else
  return _Per_CPU_Get_by_index( 0 );
#endif
}
 
static inline void _Watchdog_Set_CPU(
  Watchdog_Control *the_watchdog,
  Per_CPU_Control  *cpu
)
{
#if defined(RTEMS_SMP)
  the_watchdog->cpu = cpu;
#else
  (void) cpu;
#endif
}
 
static inline void _Watchdog_Preinitialize(
  Watchdog_Control *the_watchdog,
  Per_CPU_Control  *cpu
)
{
  _Watchdog_Set_CPU( the_watchdog, cpu );
  _Watchdog_Set_state( the_watchdog, WATCHDOG_INACTIVE );
 
#if defined(RTEMS_DEBUG)
  the_watchdog->routine = NULL;
  the_watchdog->expire = 0;
#endif
}
 
static inline void _Watchdog_Initialize(
  Watchdog_Control               *the_watchdog,
  Watchdog_Service_routine_entry  routine
)
{
  _Assert( _Watchdog_Get_state( the_watchdog ) == WATCHDOG_INACTIVE );
  the_watchdog->routine = routine;
}
 
void _Watchdog_Do_tickle(
  Watchdog_Header  *header,
  Watchdog_Control *first,
  uint64_t          now,
#if defined(RTEMS_SMP)
  ISR_lock_Control *lock,
#endif
  ISR_lock_Context *lock_context
);
 
#if defined(RTEMS_SMP)
  #define _Watchdog_Tickle( header, first, now, lock, lock_context ) \
    _Watchdog_Do_tickle( header, first, now, lock, lock_context )
#else
  #define _Watchdog_Tickle( header, first, now, lock, lock_context ) \
    _Watchdog_Do_tickle( header, first, now, lock_context )
#endif
 
void _Watchdog_Insert(
  Watchdog_Header  *header,
  Watchdog_Control *the_watchdog,
  uint64_t          expire
);
 
void _Watchdog_Remove(
  Watchdog_Header  *header,
  Watchdog_Control *the_watchdog
);
 
static inline uint64_t _Watchdog_Cancel(
  Watchdog_Header  *header,
  Watchdog_Control *the_watchdog,
  uint64_t          now
)
{
  uint64_t expire;
  uint64_t remaining;
 
  expire = the_watchdog->expire;
 
  if ( now < expire ) {
    remaining = expire - now;
  } else {
    remaining = 0;
  }
 
  _Watchdog_Remove( header, the_watchdog );
 
  return remaining;
}
 
static inline bool _Watchdog_Is_scheduled(
  const Watchdog_Control *the_watchdog
)
{
  return _Watchdog_Get_state( the_watchdog ) < WATCHDOG_INACTIVE;
}
 
static inline void _Watchdog_Next_first(
  Watchdog_Header        *header,
  const Watchdog_Control *first
)
{
  RBTree_Node *right;
 
  /*
   * This function uses the following properties of red-black trees:
   *
   * 1. Every leaf (NULL) is black.
   *
   * 2. If a node is red, then both its children are black.
   *
   * 3. Every simple path from a node to a descendant leaf contains the same
   *    number of black nodes.
   *
   * The first node has no left child.  So every path from the first node has
   * exactly one black node (including leafs).  The first node cannot have a
   * non-leaf black right child.  It may have a red right child.  In this case
   * both children must be leafs.
   */
  _Assert( header->first == &first->Node.RBTree );
  _Assert( _RBTree_Left( &first->Node.RBTree ) == NULL );
  right = _RBTree_Right( &first->Node.RBTree );
 
  if ( right != NULL ) {
    _Assert( RB_COLOR( right, Node ) == RB_RED );
    _Assert( _RBTree_Left( right ) == NULL );
    _Assert( _RBTree_Right( right ) == NULL );
    header->first = right;
  } else {
    header->first = _RBTree_Parent( &first->Node.RBTree );
  }
}
 
#define WATCHDOG_MAXIMUM_TICKS UINT64_MAX
 
#define WATCHDOG_NANOSECONDS_PER_SECOND 1000000000
 
#define WATCHDOG_BITS_FOR_1E9_NANOSECONDS 30
 
#define WATCHDOG_MAX_SECONDS 0x3ffffffff
 
static inline bool _Watchdog_Is_valid_timespec(
  const struct timespec *ts
)
{
  return ts != NULL
    && (unsigned long) ts->tv_nsec < WATCHDOG_NANOSECONDS_PER_SECOND;
}
 
static inline bool _Watchdog_Is_valid_interval_timespec(
  const struct timespec *ts
)
{
  return _Watchdog_Is_valid_timespec( ts ) && ts->tv_sec >= 0;
}
 
static inline const struct timespec * _Watchdog_Future_timespec(
  struct timespec       *now,
  const struct timespec *delta
)
{
  uint64_t sec;
 
  if ( !_Watchdog_Is_valid_interval_timespec( delta ) ) {
    return NULL;
  }
 
  sec = (uint64_t) now->tv_sec;
  sec += (uint64_t) delta->tv_sec;
  now->tv_nsec += delta->tv_nsec;
 
  /* We have 2 * (2**63 - 1) + 1 == UINT64_MAX */
  if ( now->tv_nsec >= WATCHDOG_NANOSECONDS_PER_SECOND ) {
    now->tv_nsec -= WATCHDOG_NANOSECONDS_PER_SECOND;
    ++sec;
  }
 
  if ( sec <= INT64_MAX ) {
    now->tv_sec = sec;
  } else {
    now->tv_sec = INT64_MAX;
  }
 
  return now;
}
 
static inline bool _Watchdog_Is_far_future_timespec(
  const struct timespec *ts
)
{
  return ts->tv_sec > WATCHDOG_MAX_SECONDS;
}
 
static inline uint64_t _Watchdog_Ticks_from_seconds(
  uint32_t seconds
)
{
  uint64_t ticks = seconds;
 
  ticks <<= WATCHDOG_BITS_FOR_1E9_NANOSECONDS;
 
  return ticks;
}
 
static inline uint64_t _Watchdog_Ticks_from_timespec(
  const struct timespec *ts
)
{
  uint64_t ticks;
 
  _Assert( _Watchdog_Is_valid_timespec( ts ) );
  _Assert( ts->tv_sec >= 0 );
  _Assert( !_Watchdog_Is_far_future_timespec( ts ) );
 
  ticks = (uint64_t) ts->tv_sec;
  ticks <<= WATCHDOG_BITS_FOR_1E9_NANOSECONDS;
  ticks |= (uint32_t) ts->tv_nsec;
 
  return ticks;
}
 
static inline void _Watchdog_Ticks_to_timespec(
  uint64_t         ticks,
  struct timespec *ts
)
{
  ts->tv_sec = ticks >> WATCHDOG_BITS_FOR_1E9_NANOSECONDS;
  ts->tv_nsec = ticks & ( ( 1U << WATCHDOG_BITS_FOR_1E9_NANOSECONDS ) - 1 );
}
 
static inline uint64_t _Watchdog_Ticks_from_sbintime( int64_t sbt )
{
  uint64_t ticks = ( sbt >> 32 ) << WATCHDOG_BITS_FOR_1E9_NANOSECONDS;
 
  ticks |= ( (uint64_t) 1000000000 * (uint32_t) sbt ) >> 32;
 
  return ticks;
}
 
static inline void _Watchdog_Per_CPU_acquire_critical(
  Per_CPU_Control  *cpu,
  ISR_lock_Context *lock_context
)
{
  _ISR_lock_Acquire( &cpu->Watchdog.Lock, lock_context );
}
 
static inline void _Watchdog_Per_CPU_release_critical(
  Per_CPU_Control  *cpu,
  ISR_lock_Context *lock_context
)
{
  _ISR_lock_Release( &cpu->Watchdog.Lock, lock_context );
}
 
static inline uint64_t _Watchdog_Per_CPU_insert_ticks(
  Watchdog_Control  *the_watchdog,
  Per_CPU_Control   *cpu,
  Watchdog_Interval  ticks
)
{
  ISR_lock_Context  lock_context;
  Watchdog_Header  *header;
  uint64_t          expire;
 
  header = &cpu->Watchdog.Header[ PER_CPU_WATCHDOG_TICKS ];
 
  _Watchdog_Set_CPU( the_watchdog, cpu );
 
  _Watchdog_Per_CPU_acquire_critical( cpu, &lock_context );
  expire = ticks + cpu->Watchdog.ticks;
  _Watchdog_Insert(header, the_watchdog, expire);
  _Watchdog_Per_CPU_release_critical( cpu, &lock_context );
  return expire;
}
 
static inline uint64_t _Watchdog_Per_CPU_insert(
  Watchdog_Control *the_watchdog,
  Per_CPU_Control  *cpu,
  Watchdog_Header  *header,
  uint64_t          expire
)
{
  ISR_lock_Context lock_context;
 
  _Watchdog_Set_CPU( the_watchdog, cpu );
 
  _Watchdog_Per_CPU_acquire_critical( cpu, &lock_context );
  _Watchdog_Insert( header, the_watchdog, expire );
  _Watchdog_Per_CPU_release_critical( cpu, &lock_context );
  return expire;
}
 
static inline void _Watchdog_Per_CPU_remove(
  Watchdog_Control *the_watchdog,
  Per_CPU_Control  *cpu,
  Watchdog_Header  *header
)
{
  ISR_lock_Context lock_context;
 
  _Watchdog_Per_CPU_acquire_critical( cpu, &lock_context );
  _Watchdog_Remove(
    header,
    the_watchdog
  );
  _Watchdog_Per_CPU_release_critical( cpu, &lock_context );
}
 
static inline void _Watchdog_Per_CPU_remove_ticks(
  Watchdog_Control *the_watchdog
)
{
  Per_CPU_Control *cpu;
 
  cpu = _Watchdog_Get_CPU( the_watchdog );
  _Watchdog_Per_CPU_remove(
    the_watchdog,
    cpu,
    &cpu->Watchdog.Header[ PER_CPU_WATCHDOG_TICKS ]
  );
}
 
#ifdef __cplusplus
}
#endif
 
#endif
/* end of include file */