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#include <u.h>
#include <libc.h>
#include <thread.h>
#include <bio.h>
#include "apl9.h"
#define STACKSIZE (8*1024*1024) /* 8 MB */
typedef struct SpawnData SpawnData;
struct SpawnData
{
Function func;
Array *left;
Array *right;
Channel *setupdone;
};
static void newprocfn(void *);
static ThreadData *newthreaddata(void);
/* global data */
static Lock threadlock;
static int nthreads;
static ThreadData **threads;
int mainstacksize = STACKSIZE;
void
initthreads(void)
{
ThreadData *td = newthreaddata();
void **tdptr = threaddata();
*tdptr = td;
}
int
spawnthread(Function f, Array *left, Array *right)
{
/* lock the data structures */
/* Spawn a new proc */
/* Allocate a new mailbox */
/* Send a message back to spawnthread that the setup is ready */
/* In spawnthread: unlock datastructures, return thread id */
/* in new proc:
run runfunc
lock datastructures
delete mailbox
unlock datastructures
exit proc
*/
Channel *setupdone = chancreate(sizeof(int), 0);
SpawnData *sp = malloc(sizeof(SpawnData));
sp->func = f;
sp->left = left ? duparray(left) : nil;
sp->right = duparray(right);
sp->setupdone = setupdone;
int id = proccreate(newprocfn, sp, STACKSIZE);
recv(setupdone, nil); /* wait for new proc to signal that the setup is done */
chanfree(setupdone);
return id;
}
ThreadData *
getthreaddata(void)
{
void **tdptr = threaddata();
return (ThreadData *)*tdptr;
}
void
messagesend(Array *a, int id)
{
ThreadData *td = nil;
lock(&threadlock);
for(int i = 0; i < nthreads && td == nil; i++)
if(threads[i]->id == id)
td = threads[i];
unlock(&threadlock);
if(td != nil){
qlock(&td->lock);
Mail *newmail = malloc(sizeof(Mail));
newmail->contents = fnSame(a);
newmail->next = 0;
if(td->lastmail != nil)
td->lastmail->next = newmail;
else
td->mail = newmail;
td->lastmail = newmail;
rwakeup(&td->empty);
qunlock(&td->lock);
}
}
Array *
messagerecv(Function match, int timeout)
{
USED(timeout);
USED(match);
ThreadData *td = getthreaddata();
qlock(&td->lock);
while(td->mail == nil)
rsleep(&td->empty);
Mail *m = td->mail;
td->mail = m->next;
if(td->mail == nil)
td->lastmail = nil;
qunlock(&td->lock);
Array *a = m->contents;
free(m);
return a;
}
static void
newprocfn(void *data)
{
SpawnData *sp = (SpawnData *)data;
ThreadData *td = newthreaddata();
void **tdptr = threaddata();
*tdptr = td;
int done = 1;
send(sp->setupdone, &done);
runfunc(sp->func, sp->left, sp->right);
lock(&threadlock);
/* TODO remove thread */
unlock(&threadlock);
freearray(sp->left);
freearray(sp->right);
free(sp);
free(td);
}
static ThreadData *
newthreaddata(void)
{
ThreadData *td = mallocz(sizeof(ThreadData), 1);
td->id = threadid();
td->currentdfn = nil;
td->mail = 0;
td->lastmail = 0;
td->empty.l = &td->lock;
lock(&threadlock);
nthreads++;
threads = realloc(threads, sizeof(ThreadData *) * nthreads);
threads[nthreads-1] = td;
unlock(&threadlock);
return td;
}
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