void
_sched(void)
{
Proc *p;
Thread *t;
Resched:
p = _threadgetproc();
if((t = p->thread) != nil){
needstack(128);
_threaddebug(DBGSCHED, "pausing, state=%s", psstate(t->state));
if(setjmp(t->sched)==0)
longjmp(p->sched, 1);
return;
}else{
t = runthread(p);
if(t == nil){
_threaddebug(DBGSCHED, "all threads gone; exiting");
_schedexit(p);
}
_threaddebug(DBGSCHED, "running %d.%d", t->proc->pid, t->id);
p->thread = t;
if(t->moribund){
_threaddebug(DBGSCHED, "%d.%d marked to die");
goto Resched;
}
t->state = Running;
t->nextstate = Ready;
longjmp(t->sched, 1);
}
}
int
chanalt(Alt *a)
{
int i, j, ncan, n, canblock;
Channel *c;
Task *t;
needstack(512);
for(i=0; a[i].op != CHANEND && a[i].op != CHANNOBLK; i++)
;
n = i;
canblock = a[i].op == CHANEND;
t = taskrunning;
//所有alt指向正在运行的task
for(i=0; i<n; i++){
a[i].task = t;
a[i].xalt = a;
}
ncan = 0;
for(i=0; i<n; i++){
if(altcanexec(&a[i])){
ncan++;
}
}
if(ncan){
j = rand()%ncan;
for(i=0; i<n; i++){
if(altcanexec(&a[i])){
if(j-- == 0){
altexec(&a[i]);
return i;
}
}
}
}
if(!canblock)
return -1;
for(i=0; i<n; i++){
if(a[i].op != CHANNOP)
altqueue(&a[i]);
}
taskswitch();
/*
* the guy who ran the op took care of dequeueing us
* and then set a[0].alt to the one that was executed.
*/
return a[0].xalt - a;
}
static void
dotextbin(Hio *io, Graph *g)
{
int i, nbin;
Statbin *b, bin[2000]; /* 32 kB, but whack is worse */
needstack(8192); /* double check that bin didn't kill us */
nbin = 100;
binstats(g->fn, g->arg, g->t0, g->t1, bin, nbin);
hprint(io, "stats\n\n");
for(i=0; i<nbin; i++){
b = &bin[i];
hprint(io, "%d: nsamp=%d min=%d max=%d avg=%d\n",
i, b->nsamp, b->min, b->max, b->avg);
}
}
int
chanalt(Alt *a)
{
int i, j, ncan, n, canblock;
Channel *c;
Task *t;
needstack(512);
for(i=0; a[i].op != CHANEND && a[i].op != CHANNOBLK; i++)
;
n = i;
canblock = a[i].op == CHANEND;
t = taskrunning;
for(i=0; i<n; i++){
a[i].task = t;
a[i].xalt = a;
}
if(dbgalt) print("alt ");
ncan = 0;
for(i=0; i<n; i++){
c = a[i].c;
if(dbgalt) print(" %c:", "esrnb"[a[i].op]);
if(dbgalt) { if(c->name) print("%s", c->name); else print("%p", c); }
if(altcanexec(&a[i])){
if(dbgalt) print("*");
ncan++;
}
}
if(ncan){
j = rand()%ncan;
for(i=0; i<n; i++){
if(altcanexec(&a[i])){
if(j-- == 0){
if(dbgalt){
c = a[i].c;
print(" => %c:", "esrnb"[a[i].op]);
if(c->name) print("%s", c->name); else print("%p", c);
print("\n");
}
altexec(&a[i]);
return i;
}
}
}
}
if(dbgalt)print("\n");
if(!canblock)
return -1;
for(i=0; i<n; i++){
if(a[i].op != CHANNOP)
altqueue(&a[i]);
}
taskswitch();
/*
* the guy who ran the op took care of dequeueing us
* and then set a[0].alt to the one that was executed.
*/
return a[0].xalt - a;
}
static KeySym
__xtoplan9kbd(XEvent *e)
{
KeySym k;
if(e->xany.type != KeyPress)
return -1;
needstack(64*1024); /* X has some *huge* buffers in openobject */
/* and they're even bigger on SuSE */
XLookupString((XKeyEvent*)e,NULL,0,&k,NULL);
if(k == NoSymbol)
return -1;
if(k&0xFF00){
switch(k){
case XK_BackSpace:
case XK_Tab:
case XK_Escape:
case XK_Delete:
case XK_KP_0:
case XK_KP_1:
case XK_KP_2:
case XK_KP_3:
case XK_KP_4:
case XK_KP_5:
case XK_KP_6:
case XK_KP_7:
case XK_KP_8:
case XK_KP_9:
case XK_KP_Divide:
case XK_KP_Multiply:
case XK_KP_Subtract:
case XK_KP_Add:
case XK_KP_Decimal:
k &= 0x7F;
break;
case XK_Linefeed:
k = '\r';
break;
case XK_KP_Space:
k = ' ';
break;
case XK_Home:
case XK_KP_Home:
k = Khome;
break;
case XK_Left:
case XK_KP_Left:
k = Kleft;
break;
case XK_Up:
case XK_KP_Up:
k = Kup;
break;
case XK_Down:
case XK_KP_Down:
k = Kdown;
break;
case XK_Right:
case XK_KP_Right:
k = Kright;
break;
case XK_Page_Down:
case XK_KP_Page_Down:
k = Kpgdown;
break;
case XK_End:
case XK_KP_End:
k = Kend;
break;
case XK_Page_Up:
case XK_KP_Page_Up:
k = Kpgup;
break;
case XK_Insert:
case XK_KP_Insert:
k = Kins;
break;
case XK_KP_Enter:
case XK_Return:
k = '\n';
break;
case XK_Alt_L:
case XK_Meta_L: /* Shift Alt on PCs */
case XK_Alt_R:
case XK_Meta_R: /* Shift Alt on PCs */
case XK_Multi_key:
return -1;
default: /* not ISO-1 or tty control */
if(k>0xff) {
k = _p9keysym2ucs(k);
if(k==-1) return -1;
}
}
}
/* Compensate for servers that call a minus a hyphen */
if(k == XK_hyphen)
k = XK_minus;
/* Do control mapping ourselves if translator doesn't */
if(e->xkey.state&ControlMask)
k &= 0x9f;
if(k == NoSymbol) {
return -1;
}
return k+0;
}
// 协程切换
void
taskswitch(void)
{
needstack(0);
contextswitch(&taskrunning->context, &taskschedcontext);
}
Memimage*
statgraph(Graph *g)
{
int i, nbin, x, lo, hi, min, max, first;
Memimage *m;
Rectangle r;
Statbin *b, bin[2000]; /* 32 kB, but whack is worse */
needstack(8192); /* double check that bin didn't kill us */
if(g->wid <= MinWidth)
g->wid = DefaultWidth;
if(g->ht <= MinHeight)
g->ht = DefaultHeight;
if(g->wid > nelem(bin))
g->wid = nelem(bin);
if(g->fill < 0)
g->fill = ((uint)(uintptr)g->arg>>8)%nelem(lofill);
if(g->fill > nelem(lofill))
g->fill %= nelem(lofill);
nbin = g->wid - (Left+Right);
binstats(g->fn, g->arg, g->t0, g->t1, bin, nbin);
/*
* compute bounds
*/
min = g->min;
max = g->max;
if(min < 0 || max <= min){
min = max = 0;
first = 1;
for(i=0; i<nbin; i++){
b = &bin[i];
if(b->nsamp == 0)
continue;
if(first || b->min < min)
min = b->min;
if(first || b->max > max)
max = b->max;
first = 0;
}
}
qlock(&memdrawlock);
ginit();
if(smallfont==nil || black==nil || blue==nil || red==nil || hifill[0]==nil || lofill[0]==nil){
werrstr("graphics initialization failed: %r");
qunlock(&memdrawlock);
return nil;
}
/* fresh image */
m = allocmemimage(Rect(0,0,g->wid,g->ht), ABGR32);
if(m == nil){
qunlock(&memdrawlock);
return nil;
}
r = Rect(Left, Top, g->wid-Right, g->ht-Bottom);
memfillcolor(m, DTransparent);
/* x axis */
memimagedraw(m, Rect(r.min.x, r.max.y, r.max.x, r.max.y+1), black, ZP, memopaque, ZP, S);
/* y labels */
drawlabel(m, r.min, max);
if(min != 0)
drawlabel(m, Pt(r.min.x, r.max.y-smallfont->height), min);
/* actual data */
for(i=0; i<nbin; i++){
b = &bin[i];
if(b->nsamp == 0)
continue;
lo = scalept(b->min, min, max, r.max.y, r.min.y);
hi = scalept(b->max, min, max, r.max.y, r.min.y);
x = r.min.x+i;
hi-=2;
memimagedraw(m, Rect(x, hi, x+1,lo), hifill[g->fill%nelem(hifill)], ZP, memopaque, ZP, S);
memimagedraw(m, Rect(x, lo, x+1, r.max.y), lofill[g->fill%nelem(lofill)], ZP, memopaque, ZP, S);
}
if(bin[nbin-1].nsamp)
drawlabel(m, Pt(r.max.x, r.min.y+(Dy(r)-smallfont->height)/2), bin[nbin-1].avg);
qunlock(&memdrawlock);
return m;
}
void
taskswitch(void)
{//主动进行协程切换，其实就是切换到main协程，到那里去进行实际的切换
needstack(0);//检测堆栈溢出
contextswitch(&taskrunning->context, &taskschedcontext);
}