diff options
Diffstat (limited to 'src/pkg/runtime/thread_netbsd.c')
-rw-r--r-- | src/pkg/runtime/thread_netbsd.c | 113 |
1 files changed, 83 insertions, 30 deletions
diff --git a/src/pkg/runtime/thread_netbsd.c b/src/pkg/runtime/thread_netbsd.c index 1b2df85cd..f333c6dd8 100644 --- a/src/pkg/runtime/thread_netbsd.c +++ b/src/pkg/runtime/thread_netbsd.c @@ -11,7 +11,7 @@ enum ESRCH = 3, ENOTSUP = 91, - // From NetBSD's sys/time.h + // From NetBSD's <sys/time.h> CLOCK_REALTIME = 0, CLOCK_VIRTUAL = 1, CLOCK_PROF = 2, @@ -20,9 +20,15 @@ enum extern SigTab runtime·sigtab[]; -extern int64 runtime·rfork_thread(int32 flags, void *stack, M *m, G *g, void (*fn)(void)); -extern int32 runtime·thrsleep(void *ident, int32 clock_id, void *tsp, void *lock); -extern int32 runtime·thrwakeup(void *ident, int32 n); +static Sigset sigset_none; +static Sigset sigset_all = { ~(uint32)0, ~(uint32)0, ~(uint32)0, ~(uint32)0, }; + +extern void runtime·getcontext(UcontextT *context); +extern int32 runtime·lwp_create(UcontextT *context, uintptr flags, void *lwpid); +extern void runtime·lwp_mcontext_init(void *mc, void *stack, M *mp, G *gp, void (*fn)(void)); +extern int32 runtime·lwp_park(Timespec *abstime, int32 unpark, void *hint, void *unparkhint); +extern int32 runtime·lwp_unpark(int32 lwp, void *hint); +extern int32 runtime·lwp_self(void); // From NetBSD's <sys/sysctl.h> #define CTL_HW 6 @@ -68,13 +74,30 @@ runtime·semasleep(int64 ns) if(m->waitsemacount == 0) { // sleep until semaphore != 0 or timeout. // thrsleep unlocks m->waitsemalock. - if(ns < 0) - runtime·thrsleep(&m->waitsemacount, 0, nil, &m->waitsemalock); - else { + if(ns < 0) { + // TODO(jsing) - potential deadlock! + // + // There is a potential deadlock here since we + // have to release the waitsemalock mutex + // before we call lwp_park() to suspend the + // thread. This allows another thread to + // release the lock and call lwp_unpark() + // before the thread is actually suspended. + // If this occurs the current thread will end + // up sleeping indefinitely. Unfortunately + // the NetBSD kernel does not appear to provide + // a mechanism for unlocking the userspace + // mutex once the thread is actually parked. + runtime·atomicstore(&m->waitsemalock, 0); + runtime·lwp_park(nil, 0, &m->waitsemacount, nil); + } else { ns += runtime·nanotime(); ts.tv_sec = ns/1000000000LL; ts.tv_nsec = ns%1000000000LL; - runtime·thrsleep(&m->waitsemacount, CLOCK_REALTIME, &ts, &m->waitsemalock); + // TODO(jsing) - potential deadlock! + // See above for details. + runtime·atomicstore(&m->waitsemalock, 0); + runtime·lwp_park(&ts, 0, &m->waitsemacount, nil); } // reacquire lock while(runtime·xchg(&m->waitsemalock, 1)) @@ -112,39 +135,41 @@ runtime·semawakeup(M *mp) while(runtime·xchg(&mp->waitsemalock, 1)) runtime·osyield(); mp->waitsemacount++; - ret = runtime·thrwakeup(&mp->waitsemacount, 1); + // TODO(jsing) - potential deadlock, see semasleep() for details. + // Confirm that LWP is parked before unparking... + ret = runtime·lwp_unpark(mp->procid, &mp->waitsemacount); if(ret != 0 && ret != ESRCH) runtime·printf("thrwakeup addr=%p sem=%d ret=%d\n", &mp->waitsemacount, mp->waitsemacount, ret); // spin-mutex unlock runtime·atomicstore(&mp->waitsemalock, 0); } -// From NetBSD's sys/param.h -#define RFPROC (1<<4) /* change child (else changes curproc) */ -#define RFMEM (1<<5) /* share `address space' */ -#define RFNOWAIT (1<<6) /* parent need not wait() on child */ -#define RFTHREAD (1<<13) /* create a thread, not a process */ - void -runtime·newosproc(M *m, G *g, void *stk, void (*fn)(void)) +runtime·newosproc(M *mp, void *stk) { - int32 flags; + UcontextT uc; int32 ret; - flags = RFPROC | RFTHREAD | RFMEM | RFNOWAIT; - - if (0) { + if(0) { runtime·printf( - "newosproc stk=%p m=%p g=%p fn=%p id=%d/%d ostk=%p\n", - stk, m, g, fn, m->id, m->tls[0], &m); + "newosproc stk=%p m=%p g=%p id=%d/%d ostk=%p\n", + stk, mp, mp->g0, mp->id, (int32)mp->tls[0], &mp); } - m->tls[0] = m->id; // so 386 asm can find it + mp->tls[0] = mp->id; // so 386 asm can find it + + runtime·getcontext(&uc); + + uc.uc_flags = _UC_SIGMASK | _UC_CPU; + uc.uc_link = nil; + uc.uc_sigmask = sigset_all; + + runtime·lwp_mcontext_init(&uc.uc_mcontext, stk, mp, mp->g0, runtime·mstart); - if((ret = runtime·rfork_thread(flags, stk, m, g, fn)) < 0) { + ret = runtime·lwp_create(&uc, 0, &mp->procid); + + if(ret < 0) { runtime·printf("runtime: failed to create new OS thread (have %d already; errno=%d)\n", runtime·mcount() - 1, -ret); - if (ret == -ENOTSUP) - runtime·printf("runtime: is kern.rthreads disabled?\n"); runtime·throw("runtime.newosproc"); } } @@ -162,12 +187,30 @@ runtime·goenvs(void) } // Called to initialize a new m (including the bootstrap m). +// Called on the parent thread (main thread in case of bootstrap), can allocate memory. +void +runtime·mpreinit(M *mp) +{ + mp->gsignal = runtime·malg(32*1024); +} + +// Called to initialize a new m (including the bootstrap m). +// Called on the new thread, can not allocate memory. void runtime·minit(void) { + m->procid = runtime·lwp_self(); + // Initialize signal handling - m->gsignal = runtime·malg(32*1024); - runtime·signalstack(m->gsignal->stackguard - StackGuard, 32*1024); + runtime·signalstack((byte*)m->gsignal->stackguard - StackGuard, 32*1024); + runtime·sigprocmask(SIG_SETMASK, &sigset_none, nil); +} + +// Called from dropm to undo the effect of an minit. +void +runtime·unminit(void) +{ + runtime·signalstack(nil, 0); } void @@ -224,12 +267,22 @@ runtime·badcallback(void) runtime·write(2, badcallback, sizeof badcallback - 1); } -static int8 badsignal[] = "runtime: signal received on thread not created by Go.\n"; +static int8 badsignal[] = "runtime: signal received on thread not created by Go: "; // This runs on a foreign stack, without an m or a g. No stack split. #pragma textflag 7 void -runtime·badsignal(void) +runtime·badsignal(int32 sig) { + if (sig == SIGPROF) { + return; // Ignore SIGPROFs intended for a non-Go thread. + } runtime·write(2, badsignal, sizeof badsignal - 1); + if (0 <= sig && sig < NSIG) { + // Call runtime·findnull dynamically to circumvent static stack size check. + static int32 (*findnull)(byte*) = runtime·findnull; + runtime·write(2, runtime·sigtab[sig].name, findnull((byte*)runtime·sigtab[sig].name)); + } + runtime·write(2, "\n", 1); + runtime·exit(1); } |