threads.h

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/*
 * threads.h - platform-dependent CPU feature query, threads, and atomic ops
 *
 * (C) Copyright 1994-2022 John E. Stone
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * $Id: threads.h,v 1.67 2022/02/21 16:45:19 johns Exp $
 *
 */ 

/* 
 * XXX will need to rename threads.[ch] src to avoid collision with
 * the new headers included in the C11 standard and later
 */

#ifndef RT_THREADS_INC
#define RT_THREADS_INC 1

#ifdef __cplusplus
extern "C" {
#endif

/* define which thread calls to use */
#if defined(USEPOSIXTHREADS) && defined(USEUITHREADS)
#error You may only define USEPOSIXTHREADS or USEUITHREADS, but not both
#endif

/* POSIX Threads */
#if defined(_AIX) || defined(__APPLE__) || defined(_CRAY) || defined(__hpux) || defined(__irix) || defined(__linux) || defined(__osf__) ||  defined(__PARAGON__)
#if !defined(USEUITHREADS) && !defined(USEPOSIXTHREADS)
#define USEPOSIXTHREADS
#endif
#endif

/* Unix International Threads */
#if defined(SunOS)
#if !defined(USEPOSIXTHREADS) && !defined(USEUITHREADS)
#define USEUITHREADS
#endif
#endif

/*
 * CPU capability flags 
 */
#define CPU_SMTDEPTH_UNKNOWN           0  
#define CPU_UNKNOWN           0x00000001  
/* Intel x86 CPU features we may need at runtime */
#define CPU_HT                0x00000010  
#define CPU_HYPERVISOR        0x00000020  
#define CPU_SSE2              0x00000100  
#define CPU_SSE4_1            0x00000200  
#define CPU_F16C              0x00000400  
#define CPU_FMA               0x00000800  
#define CPU_AVX               0x00001000  
#define CPU_AVX2              0x00002000  
#define CPU_AVX512F           0x00010000  
#define CPU_AVX512CD          0x00020000  
#define CPU_AVX512ER          0x00040000  
#define CPU_AVX512PF          0x00080000  
#define CPU_KNL         (CPU_AVX512F | CPU_AVX512CD | \
                         CPU_AVX512ER | CPU_AVX512PF)   
/* ARM CPU features we may need at runtime */
#define CPU_ARM64_CPUID       0x00000010  
#define CPU_ARM64_CRC32       0x00000020  
#define CPU_ARM64_FP          0x00000080  
#define CPU_ARM64_HPFP        0x00000080  
#define CPU_ARM64_AES         0x00000100  
#define CPU_ARM64_ATOMICS     0x00000200  
#define CPU_ARM64_ASIMD       0x00000400  
#define CPU_ARM64_ASIMDDP     0x00000800  
#define CPU_ARM64_ASIMDHP     0x00001000  
#define CPU_ARM64_ASIMDRDM    0x00002000  
#define CPU_ARM64_ASIMDFHM    0x00004000  
#define CPU_ARM64_SVE         0x00008000  
#define CPU_ARM64_SHA512      0x00010000  
#define CPU_ARM64_SHA1        0x00020000  
#define CPU_ARM64_SHA2        0x00040000  
#define CPU_ARM64_SHA3        0x00080000  
typedef struct rt_cpu_caps_struct {
  unsigned int flags;
  int smtdepth;
} rt_cpu_caps_t;


#ifdef THR
#ifdef USEPOSIXTHREADS
#include <pthread.h>

typedef pthread_t        rt_thread_t;  
typedef pthread_mutex_t   rt_mutex_t;  
typedef pthread_cond_t     rt_cond_t;  
typedef struct rwlock_struct {
  pthread_mutex_t lock;          
  int rwlock;                    
  pthread_cond_t  rdrs_ok;       
  unsigned int waiting_writers;  
  pthread_cond_t  wrtr_ok;       
} rt_rwlock_t;

#endif

#ifdef USEUITHREADS
#include <thread.h>

typedef thread_t  rt_thread_t;
typedef mutex_t   rt_mutex_t;
typedef cond_t    rt_cond_t;
typedef rwlock_t  rt_rwlock_t;
#endif


#ifdef _MSC_VER
#include <windows.h>
typedef HANDLE rt_thread_t;
typedef CRITICAL_SECTION rt_mutex_t;

#if 0 && (NTDDI_VERSION >= NTDDI_WS08 || _WIN32_WINNT > 0x0600)
/* Use native condition variables only with Windows Server 2008 and newer... */
#define RTUSEWIN2008CONDVARS 1
typedef CONDITION_VARIABLE rt_cond_t;
#else
/* Every version of Windows prior to Vista/WS2008 must emulate */
/* variables using manually resettable events or other schemes */

/* For higher performance, use interlocked memory operations   */
/* rather than locking/unlocking mutexes when manipulating     */
/* internal state.                                             */
#if 1
#define RTUSEINTERLOCKEDATOMICOPS 1
#endif
#define RT_COND_SIGNAL    0
#define RT_COND_BROADCAST 1
typedef struct {
  LONG waiters;                  
  CRITICAL_SECTION waiters_lock; 
  HANDLE events[2];              
} rt_cond_t;
#endif

typedef struct rwlock_struct {
  rt_mutex_t lock;               
  int rwlock;                    
  rt_cond_t  rdrs_ok;            
  unsigned int waiting_writers;  
  rt_cond_t  wrtr_ok;            
} rt_rwlock_t;

#endif
#endif /* _MSC_VER */


#ifndef THR
typedef int rt_thread_t;
typedef int rt_mutex_t;
typedef int rt_cond_t;
typedef int rt_rwlock_t;
#endif

#if defined(USENETBSDATOMICS) 
#include <sys/atomic.h>
#elif defined(USESOLARISATOMICS)
#include <atomic.h>
#endif

typedef struct atomic_int_struct {
  int padding1[8];        
  rt_mutex_t lock;        
#if defined(USENETBSDATOMICS)
  unsigned int val;       
#elif defined(USESOLARISATOMICS)
  unsigned int val;       
#elif defined(USEWIN32ATOMICS)
  LONG val;               
#else
  int val;                
#endif
  int padding2[8];        
} rt_atomic_int_t;


typedef struct barrier_struct {
  int padding1[8];        
  rt_mutex_t lock;        
  int n_clients;          
  int n_waiting;          
  int phase;              
  int sum;                
  int result;             
  rt_cond_t wait_cv;      
  int padding2[8];        
} rt_barrier_t;


typedef struct rt_run_barrier_struct {
  int padding1[8];        
  rt_mutex_t lock;        
  int n_clients;          
  int n_waiting;          
  int phase;              
  void * (*fctn)(void *); 
  void * parms;           
  void * (*rslt)(void *); 
  void * rsltparms;       
  rt_cond_t wait_cv;      
  int padding2[8];        
} rt_run_barrier_t;


/*
 * Routines for querying processor counts, and managing CPU affinity
 */
int rt_thread_numphysprocessors(void);

int rt_thread_numprocessors(void);

int rt_cpu_capability_flags(rt_cpu_caps_t *cpucaps);

/* A return value of zero means we don't know */
int rt_cpu_smt_depth(void);

int * rt_cpu_affinitylist(int *cpuaffinitycount);

int rt_thread_set_self_cpuaffinity(int cpu);

int rt_thread_setconcurrency(int);


/*
 * Thread management
 */
int rt_thread_create(rt_thread_t *, void * fctn(void *), void *);

int rt_thread_join(rt_thread_t, void **);


/*
 * Mutex management
 */
int rt_mutex_init(rt_mutex_t *);

int rt_mutex_lock(rt_mutex_t *);

int rt_mutex_trylock(rt_mutex_t *);

int rt_mutex_spin_lock(rt_mutex_t *);

int rt_mutex_unlock(rt_mutex_t *);

int rt_mutex_destroy(rt_mutex_t *);


/*
 * Condition variable management
 */
int rt_cond_init(rt_cond_t *);

int rt_cond_destroy(rt_cond_t *);

int rt_cond_wait(rt_cond_t *, rt_mutex_t *);

int rt_cond_signal(rt_cond_t *);

int rt_cond_broadcast(rt_cond_t *);


/*
 * Atomic operations on integers
 */
int rt_atomic_int_init(rt_atomic_int_t * atomp, int val);

int rt_atomic_int_destroy(rt_atomic_int_t * atomp);

int rt_atomic_int_set(rt_atomic_int_t * atomp, int val);

int rt_atomic_int_get(rt_atomic_int_t * atomp);

int rt_atomic_int_fetch_and_add(rt_atomic_int_t * atomp, int inc);

int rt_atomic_int_add_and_fetch(rt_atomic_int_t * atomp, int inc);


/*
 * Reader/writer lock management
 */
int rt_rwlock_init(rt_rwlock_t *);

int rt_rwlock_readlock(rt_rwlock_t *);

int rt_rwlock_writelock(rt_rwlock_t *);

int rt_rwlock_unlock(rt_rwlock_t *);


/*
 * counting barrier
 */
rt_barrier_t * rt_thread_barrier_init(int n_clients);

int rt_thread_barrier_init_proc_shared(rt_barrier_t *, int n_clients);

void rt_thread_barrier_destroy(rt_barrier_t *barrier);

int rt_thread_barrier(rt_barrier_t *barrier, int increment);


/*
 * This is a symmetric barrier routine designed to be used
 * in implementing a sleepable thread pool.
 */
int rt_thread_run_barrier_init(rt_run_barrier_t *barrier, int n_clients);

void rt_thread_run_barrier_destroy(rt_run_barrier_t *barrier);

void * (*rt_thread_run_barrier(rt_run_barrier_t *barrier,
                                void * fctn(void*),
                                void * parms,
                                void **rsltparms))(void *);

int rt_thread_run_barrier_poll(rt_run_barrier_t *barrier);


typedef struct rt_tasktile_struct {
  int start;         
  int end;           
} rt_tasktile_t;


/*
 * tile stack
 */
#define RT_TILESTACK_EMPTY -1

typedef struct {
  rt_mutex_t mtx;    
  int growthrate;    
  int size;          
  int top;           
  rt_tasktile_t *s;  
} rt_tilestack_t;

int rt_tilestack_init(rt_tilestack_t *s, int size);

void rt_tilestack_destroy(rt_tilestack_t *);

int rt_tilestack_compact(rt_tilestack_t *);

int rt_tilestack_push(rt_tilestack_t *, const rt_tasktile_t *);

int rt_tilestack_pop(rt_tilestack_t *, rt_tasktile_t *);

int rt_tilestack_popall(rt_tilestack_t *);

int rt_tilestack_empty(rt_tilestack_t *);


#define RT_SCHED_DONE     -1   
#define RT_SCHED_CONTINUE  0   
typedef struct rt_shared_iterator_struct {
  rt_mutex_t mtx;      
  int start;           
  int end;             
  int current;         
  int fatalerror;      
} rt_shared_iterator_t;

int rt_shared_iterator_init(rt_shared_iterator_t *it);

int rt_shared_iterator_destroy(rt_shared_iterator_t *it);

int rt_shared_iterator_set(rt_shared_iterator_t *it, rt_tasktile_t *tile);

int rt_shared_iterator_next_tile(rt_shared_iterator_t *it, int reqsize,
                                 rt_tasktile_t *tile);

int rt_shared_iterator_setfatalerror(rt_shared_iterator_t *it);

int rt_shared_iterator_getfatalerror(rt_shared_iterator_t *it);


/*
 * Thread pool.
 */
#define RT_THREADPOOL_DEVLIST_CPUSONLY NULL

#define RT_THREADPOOL_DEVID_CPU -1

typedef struct rt_threadpool_workerdata_struct {
  int padding1[8];                        
  rt_shared_iterator_t *iter;             
  rt_tilestack_t *errorstack;             
  int threadid;                           
  int threadcount;                        
  int devid;                              
  float devspeed;                         
  void *parms;                            
  void *thrpool;                          
  int padding2[8];                        
} rt_threadpool_workerdata_t;


typedef struct rt_threadpool_struct {
  int workercount;                        
  int *devlist;                           
  rt_shared_iterator_t iter;              
  rt_tilestack_t errorstack;              
  rt_thread_t *threads;                   
  rt_threadpool_workerdata_t *workerdata; 
  rt_run_barrier_t runbar;                
} rt_threadpool_t;


rt_threadpool_t * rt_threadpool_create(int workercount, int *devlist);

int rt_threadpool_launch(rt_threadpool_t *thrpool,
                         void *fctn(void *), void *parms, int blocking);

int rt_threadpool_wait(rt_threadpool_t *thrpool);

int rt_threadpool_destroy(rt_threadpool_t *thrpool);

int rt_threadpool_get_workercount(rt_threadpool_t *thrpool);

int rt_threadpool_worker_getid(void *voiddata, int *threadid, int *threadcount);

int rt_threadpool_worker_getdevid(void *voiddata, int *devid);

int rt_threadpool_worker_setdevspeed(void *voiddata, float speed);

int rt_threadpool_worker_getdevspeed(void *voiddata, float *speed);

int rt_threadpool_worker_devscaletile(void *voiddata, int *tilesize);

int rt_threadpool_worker_getdata(void *voiddata, void **clientdata);

int rt_threadpool_sched_dynamic(rt_threadpool_t *thrpool, rt_tasktile_t *tile);

int rt_threadpool_next_tile(void *thrpool, int reqsize, rt_tasktile_t *tile);

int rt_threadpool_tile_failed(void *thrpool, rt_tasktile_t *tile);

int rt_threadpool_setfatalerror(void *thrparms);

int rt_threadpool_getfatalerror(void *thrparms);


typedef struct rt_threadlaunch_struct {
  int padding1[8];              
  rt_shared_iterator_t *iter;   
  int threadid;                 
  int threadcount;              
  void * clientdata;            
  int padding2[8];              
} rt_threadlaunch_t;

int rt_threadlaunch(int numprocs, void *clientdata, void * fctn(void *),
                    rt_tasktile_t *tile);

int rt_threadlaunch_getid(void *thrparms, int *threadid, int *threadcount);

int rt_threadlaunch_getdata(void *thrparms, void **clientdata);

int rt_threadlaunch_next_tile(void *voidparms, int reqsize,
                              rt_tasktile_t *tile);

int rt_threadlaunch_setfatalerror(void *thrparms);


#ifdef __cplusplus
}
#endif

#endif