runtime: cpu profiling support
R=r
CC=golang-dev
https://golang.org/cl/4306043
diff --git a/src/pkg/runtime/linux/arm/signal.c b/src/pkg/runtime/linux/arm/signal.c
index 843c40b..5a2b47d 100644
--- a/src/pkg/runtime/linux/arm/signal.c
+++ b/src/pkg/runtime/linux/arm/signal.c
@@ -58,6 +58,11 @@
uc = context;
r = &uc->uc_mcontext;
+ if(sig == SIGPROF) {
+ runtime·sigprof((uint8*)r->arm_pc, (uint8*)r->arm_sp, (uint8*)r->arm_lr, gp);
+ return;
+ }
+
if(gp != nil && (runtime·sigtab[sig].flags & SigPanic)) {
// Make it look like a call to the signal func.
// Have to pass arguments out of band since
@@ -119,31 +124,58 @@
runtime·sigaltstack(&st, nil);
}
+static void
+sigaction(int32 i, void (*fn)(int32, Siginfo*, void*, G*), bool restart)
+{
+ Sigaction sa;
+
+ runtime·memclr((byte*)&sa, sizeof sa);
+ sa.sa_flags = SA_ONSTACK | SA_SIGINFO | SA_RESTORER;
+ if(restart)
+ sa.sa_flags |= SA_RESTART;
+ sa.sa_mask = ~0ULL;
+ sa.sa_restorer = (void*)runtime·sigreturn;
+ sa.k_sa_handler = fn;
+ runtime·rt_sigaction(i, &sa, nil, 8);
+}
+
void
runtime·initsig(int32 queue)
{
- static Sigaction sa;
+ int32 i;
+ void *fn;
runtime·siginit();
- int32 i;
- sa.sa_flags = SA_ONSTACK | SA_SIGINFO | SA_RESTORER;
- sa.sa_mask.sig[0] = 0xFFFFFFFF;
- sa.sa_mask.sig[1] = 0xFFFFFFFF;
- sa.sa_restorer = (void*)runtime·sigreturn;
for(i = 0; i<NSIG; i++) {
if(runtime·sigtab[i].flags) {
if((runtime·sigtab[i].flags & SigQueue) != queue)
continue;
if(runtime·sigtab[i].flags & (SigCatch | SigQueue))
- sa.sa_handler = (void*)runtime·sigtramp;
+ fn = runtime·sighandler;
else
- sa.sa_handler = (void*)runtime·sigignore;
- if(runtime·sigtab[i].flags & SigRestart)
- sa.sa_flags |= SA_RESTART;
- else
- sa.sa_flags &= ~SA_RESTART;
- runtime·rt_sigaction(i, &sa, nil, 8);
+ fn = runtime·sigignore;
+ sigaction(i, fn, (runtime·sigtab[i].flags & SigRestart) != 0);
}
}
}
+
+void
+runtime·resetcpuprofiler(int32 hz)
+{
+ Sigaction sa;
+ Itimerval it;
+
+ runtime·memclr((byte*)&it, sizeof it);
+ if(hz == 0) {
+ runtime·setitimer(ITIMER_PROF, &it, nil);
+ sigaction(SIGPROF, SIG_IGN, true);
+ } else {
+ sigaction(SIGPROF, runtime·sighandler, true);
+ it.it_interval.tv_sec = 0;
+ it.it_interval.tv_usec = 1000000 / hz;
+ it.it_value = it.it_interval;
+ runtime·setitimer(ITIMER_PROF, &it, nil);
+ }
+ m->profilehz = hz;
+}
