- Move p->p_sigmask to td->td_sigmask. Signal masks will be per thread with

   a follow on commit to kern_sig.c
 - signotify() now operates on a thread since unmasked pending signals are
   stored in the thread.
 - PS_NEEDSIGCHK moves to TDF_NEEDSIGCHK.

36 files changed, 449 insertions, 315 deletions

diff --git a/sys/alpha/alpha/machdep.c b/sys/alpha/alpha/machdep.c
index 273bda5..055d3f8 100644
--- a/sys/alpha/alpha/machdep.c
+++ b/sys/alpha/alpha/machdep.c
@@ -1501,9 +1501,9 @@ osigreturn(struct thread *td,
 	 * sigmask is stored in sc_reserved, sc_mask is only used for
 	 * backward compatibility.
 	 */
-	SIGSETOLD(p->p_sigmask, ksc.sc_mask);
-	SIG_CANTMASK(p->p_sigmask);
-	signotify(p);
+	SIGSETOLD(td->td_sigmask, ksc.sc_mask);
+	SIG_CANTMASK(td->td_sigmask);
+	signotify(td);
 	PROC_UNLOCK(p);
 
 	set_regs(td, (struct reg *)ksc.sc_regs);
@@ -1583,9 +1583,9 @@ freebsd4_sigreturn(struct thread *td,
 		p->p_sigstk.ss_flags &= ~SS_ONSTACK;
 #endif
 
-	p->p_sigmask = uc.uc_sigmask;
-	SIG_CANTMASK(p->p_sigmask);
-	signotify(p);
+	td->td_sigmask = uc.uc_sigmask;
+	SIG_CANTMASK(td->td_sigmask);
+	signotify(td);
 	PROC_UNLOCK(p);
 
 	/* XXX ksc.sc_ownedfp ? */
@@ -1659,9 +1659,9 @@ sigreturn(struct thread *td,
 		p->p_sigstk.ss_flags &= ~SS_ONSTACK;
 #endif
 
-	p->p_sigmask = uc.uc_sigmask;
-	SIG_CANTMASK(p->p_sigmask);
-	signotify(p);
+	td->td_sigmask = uc.uc_sigmask;
+	SIG_CANTMASK(td->td_sigmask);
+	signotify(td);
 	PROC_UNLOCK(p);
 
 	return (EJUSTRETURN);
diff --git a/sys/alpha/osf1/osf1_signal.c b/sys/alpha/osf1/osf1_signal.c
index 718c7d9..8249c7a 100644
--- a/sys/alpha/osf1/osf1_signal.c
+++ b/sys/alpha/osf1/osf1_signal.c
@@ -451,7 +451,7 @@ osf1_signal(td, uap)
 
 			bmask = stackgap_alloc(&sg, sizeof(sigset_t));
 			PROC_LOCK(p);
-			set = p->p_sigmask;
+			set = td->td_sigmask;
 			PROC_UNLOCK(p);
 			SIGDELSET(set, signum);
 			sa.sigmask = bmask;
@@ -481,7 +481,7 @@ osf1_sigprocmask(td, uap)
 	p = td->td_proc;
 	error = 0;
 		/* Fix the return value first if needed */
-	bsd_to_osf1_sigset(&p->p_sigmask, &oss);
+	bsd_to_osf1_sigset(&td->td_sigmask, &oss);
 	td->td_retval[0] = oss;
 
 	osf1_to_bsd_sigset(&uap->mask, &bss);
@@ -490,19 +490,19 @@ osf1_sigprocmask(td, uap)
 
 	switch (uap->how) {
 	case OSF1_SIG_BLOCK:
-		SIGSETOR(p->p_sigmask, bss);
-		SIG_CANTMASK(p->p_sigmask);
+		SIGSETOR(td->td_sigmask, bss);
+		SIG_CANTMASK(td->td_sigmask);
 		break;
 
 	case OSF1_SIG_UNBLOCK:
-		SIGSETNAND(p->p_sigmask, bss);
-		signotify(p);
+		SIGSETNAND(td->td_sigmask, bss);
+		signotify(td);
 		break;
 
 	case OSF1_SIG_SETMASK:
-		p->p_sigmask = bss;
-		SIG_CANTMASK(p->p_sigmask);
-		signotify(p);
+		td->td_sigmask = bss;
+		SIG_CANTMASK(td->td_sigmask);
+		signotify(td);
 		break;
 
 	default:
@@ -528,8 +528,9 @@ osf1_sigpending(td, uap)
 
 	p = td->td_proc;
 	PROC_LOCK(p);
-	bss = p->p_siglist;
-	SIGSETAND(bss, p->p_sigmask);
+	bss = td->td_siglist;
+	SIGSETOR(bss, p->p_siglist);
+	SIGSETAND(bss, td->td_sigmask);
 	PROC_UNLOCK(p);
 	bsd_to_osf1_sigset(&bss, &oss);
 
@@ -727,9 +728,9 @@ osf1_sigreturn(struct thread *td,
 	 * sigmask is stored in sc_reserved, sc_mask is only used for
 	 * backward compatibility.
 	 */
-	osf1_to_bsd_sigset(&ksc.sc_mask, &p->p_sigmask);
-	SIG_CANTMASK(p->p_sigmask);
-	signotify(p);
+	osf1_to_bsd_sigset(&ksc.sc_mask, &td->td_sigmask);
+	SIG_CANTMASK(td->td_sigmask);
+	signotify(td);
 	PROC_UNLOCK(p);
 
 	set_regs(td, (struct reg *)ksc.sc_regs);
diff --git a/sys/amd64/amd64/machdep.c b/sys/amd64/amd64/machdep.c
index 9a1cf43..b389828 100644
--- a/sys/amd64/amd64/machdep.c
+++ b/sys/amd64/amd64/machdep.c
@@ -751,9 +751,9 @@ osigreturn(td, uap)
 	else
 		p->p_sigstk.ss_flags &= ~SS_ONSTACK;
 #endif
-	SIGSETOLD(p->p_sigmask, scp->sc_mask);
-	SIG_CANTMASK(p->p_sigmask);
-	signotify(p);
+	SIGSETOLD(td->td_sigmask, scp->sc_mask);
+	SIG_CANTMASK(td->td_sigmask);
+	signotify(td);
 	PROC_UNLOCK(p);
 	return (EJUSTRETURN);
 }
@@ -859,9 +859,9 @@ freebsd4_sigreturn(td, uap)
 		p->p_sigstk.ss_flags &= ~SS_ONSTACK;
 #endif
 
-	p->p_sigmask = ucp->uc_sigmask;
-	SIG_CANTMASK(p->p_sigmask);
-	signotify(p);
+	td->td_sigmask = ucp->uc_sigmask;
+	SIG_CANTMASK(td->td_sigmask);
+	signotify(td);
 	PROC_UNLOCK(p);
 	return (EJUSTRETURN);
 }
@@ -969,9 +969,9 @@ sigreturn(td, uap)
 		p->p_sigstk.ss_flags &= ~SS_ONSTACK;
 #endif
 
-	p->p_sigmask = ucp->uc_sigmask;
-	SIG_CANTMASK(p->p_sigmask);
-	signotify(p);
+	td->td_sigmask = ucp->uc_sigmask;
+	SIG_CANTMASK(td->td_sigmask);
+	signotify(td);
 	PROC_UNLOCK(p);
 	return (EJUSTRETURN);
 }
diff --git a/sys/coda/coda_psdev.c b/sys/coda/coda_psdev.c
index 392012b..ef237c4 100644
--- a/sys/coda/coda_psdev.c
+++ b/sys/coda/coda_psdev.c
@@ -548,7 +548,7 @@ coda_call(mntinfo, inSize, outSize, buffer)
 	 */
 	i = 0;
 	PROC_LOCK(p);
-	psig_omask = p->p_sigmask;
+	psig_omask = td->td_sigmask;
 	do {
 		error = msleep(&vmp->vm_sleep, &p->p_mtx,
 			       (coda_call_sleep|coda_pcatch), "coda_call",
@@ -563,8 +563,8 @@ coda_call(mntinfo, inSize, outSize, buffer)
 		else {
 			SIGEMPTYSET(tempset);
 			SIGADDSET(tempset, SIGIO);
-			if (SIGSETEQ(p->p_siglist, tempset)) {
-				SIGADDSET(p->p_sigmask, SIGIO);
+			if (SIGSETEQ(td->td_siglist, tempset)) {
+				SIGADDSET(td->td_sigmask, SIGIO);
 #ifdef	CODA_VERBOSE
 				printf("coda_call: tsleep returns %d SIGIO, cnt %d\n",
 				       error, i);
@@ -572,8 +572,8 @@ coda_call(mntinfo, inSize, outSize, buffer)
 			} else {
 				SIGDELSET(tempset, SIGIO);
 				SIGADDSET(tempset, SIGALRM);
-				if (SIGSETEQ(p->p_siglist, tempset)) {
-					SIGADDSET(p->p_sigmask, SIGALRM);
+				if (SIGSETEQ(td->td_siglist, tempset)) {
+					SIGADDSET(td->td_sigmask, SIGALRM);
 #ifdef	CODA_VERBOSE
 					printf("coda_call: tsleep returns %d SIGALRM, cnt %d\n",
 					       error, i);
@@ -584,25 +584,25 @@ coda_call(mntinfo, inSize, outSize, buffer)
 					       error, i);
 
 #if notyet
-					tempset = p->p_siglist;
-					SIGSETNAND(tempset, p->p_sigmask);
+					tempset = td->td_siglist;
+					SIGSETNAND(tempset, td->td_sigmask);
 					printf("coda_call: siglist = %p, sigmask = %p, mask %p\n",
-					       p->p_siglist, p->p_sigmask,
+					       td->td_siglist, td->td_sigmask,
 					       tempset);
 					break;
-					SIGSETOR(p->p_sigmask, p->p_siglist);
-					tempset = p->p_siglist;
-					SIGSETNAND(tempset, p->p_sigmask);
+					SIGSETOR(td->td_sigmask, td->td_siglist);
+					tempset = td->td_siglist;
+					SIGSETNAND(tempset, td->td_sigmask);
 					printf("coda_call: new mask, siglist = %p, sigmask = %p, mask %p\n",
-					       p->p_siglist, p->p_sigmask,
+					       td->td_siglist, td->td_sigmask,
 					       tempset);
 #endif
 				}
 			}
 		}
 	} while (error && i++ < 128 && VC_OPEN(vcp));
-	p->p_sigmask = psig_omask;
-	signotify(p);
+	td->td_sigmask = psig_omask;
+	signotify(td);
 	PROC_UNLOCK(p);
 #else
 	(void) tsleep(&vmp->vm_sleep, coda_call_sleep, "coda_call", 0);
diff --git a/sys/compat/linux/linux_signal.c b/sys/compat/linux/linux_signal.c
index 5ed0bdf..15a818f 100644
--- a/sys/compat/linux/linux_signal.c
+++ b/sys/compat/linux/linux_signal.c
@@ -236,24 +236,24 @@ linux_do_sigprocmask(struct thread *td, int how, l_sigset_t *new,
 
 	PROC_LOCK(p);
 	if (old != NULL)
-		bsd_to_linux_sigset(&p->p_sigmask, old);
+		bsd_to_linux_sigset(&td->td_sigmask, old);
 
 	if (new != NULL) {
 		linux_to_bsd_sigset(new, &mask);
 
 		switch (how) {
 		case LINUX_SIG_BLOCK:
-			SIGSETOR(p->p_sigmask, mask);
-			SIG_CANTMASK(p->p_sigmask);
+			SIGSETOR(td->td_sigmask, mask);
+			SIG_CANTMASK(td->td_sigmask);
 			break;
 		case LINUX_SIG_UNBLOCK:
-			SIGSETNAND(p->p_sigmask, mask);
-			signotify(p);
+			SIGSETNAND(td->td_sigmask, mask);
+			signotify(td);
 			break;
 		case LINUX_SIG_SETMASK:
-			p->p_sigmask = mask;
-			SIG_CANTMASK(p->p_sigmask);
-			signotify(p);
+			td->td_sigmask = mask;
+			SIG_CANTMASK(td->td_sigmask);
+			signotify(td);
 			break;
 		default:
 			error = EINVAL;
@@ -345,7 +345,7 @@ linux_sgetmask(struct thread *td, struct linux_sgetmask_args *args)
 #endif
 
 	PROC_LOCK(p);
-	bsd_to_linux_sigset(&p->p_sigmask, &mask);
+	bsd_to_linux_sigset(&td->td_sigmask, &mask);
 	PROC_UNLOCK(p);
 	td->td_retval[0] = mask.__bits[0];
 	return (0);
@@ -364,14 +364,14 @@ linux_ssetmask(struct thread *td, struct linux_ssetmask_args *args)
 #endif
 
 	PROC_LOCK(p);
-	bsd_to_linux_sigset(&p->p_sigmask, &lset);
+	bsd_to_linux_sigset(&td->td_sigmask, &lset);
 	td->td_retval[0] = lset.__bits[0];
 	LINUX_SIGEMPTYSET(lset);
 	lset.__bits[0] = args->mask;
 	linux_to_bsd_sigset(&lset, &bset);
-	p->p_sigmask = bset;
-	SIG_CANTMASK(p->p_sigmask);
-	signotify(p);
+	td->td_sigmask = bset;
+	SIG_CANTMASK(td->td_sigmask);
+	signotify(td);
 	PROC_UNLOCK(p);
 	return (0);
 }
@@ -394,7 +394,8 @@ linux_sigpending(struct thread *td, struct linux_sigpending_args *args)
 
 	PROC_LOCK(p);
 	bset = p->p_siglist;
-	SIGSETAND(bset, p->p_sigmask);
+	SIGSETOR(bset, td->td_siglist);
+	SIGSETAND(bset, td->td_sigmask);
 	bsd_to_linux_sigset(&bset, &lset);
 	PROC_UNLOCK(p);
 	mask = lset.__bits[0];
diff --git a/sys/compat/svr4/svr4_filio.c b/sys/compat/svr4/svr4_filio.c
index ca1b8db..870da5d 100644
--- a/sys/compat/svr4/svr4_filio.c
+++ b/sys/compat/svr4/svr4_filio.c
@@ -132,10 +132,10 @@ svr4_sys_read(td, uap)
      DPRINTF(("svr4_read(%d, 0x%0x, %d) = %d\n", 
 	     uap->fd, uap->buf, uap->nbyte, rv));
      if (rv == EAGAIN) {
-       DPRINTF(("sigmask = 0x%x\n", td->td_proc->p_sigmask));
+       DPRINTF(("sigmask = 0x%x\n", td->td_sigmask));
        DPRINTF(("sigignore = 0x%x\n", td->td_proc->p_sigignore));
        DPRINTF(("sigcaught = 0x%x\n", td->td_proc->p_sigcatch));
-       DPRINTF(("siglist = 0x%x\n", td->td_proc->p_siglist));
+       DPRINTF(("siglist = 0x%x\n", td->td_siglist));
      }
 
 #if defined(GROTTY_READ_HACK)
diff --git a/sys/compat/svr4/svr4_signal.c b/sys/compat/svr4/svr4_signal.c
index 3e688e6..c45b7cb 100644
--- a/sys/compat/svr4/svr4_signal.c
+++ b/sys/compat/svr4/svr4_signal.c
@@ -481,7 +481,7 @@ sighold:
 
 			set = stackgap_alloc(&sg, sizeof(sigset_t));
 			PROC_LOCK(td->td_proc);
-			*set = td->td_proc->p_sigmask;
+			*set = td->td_sigmask;
 			PROC_UNLOCK(td->td_proc);
 			SIGDELSET(*set, signum);
 			sa.sigmask = set;
@@ -507,7 +507,7 @@ svr4_sys_sigprocmask(td, uap)
 	if (uap->oset != NULL) {
 		/* Fix the return value first if needed */
 		PROC_LOCK(td->td_proc);
-		bsd_to_svr4_sigset(&td->td_proc->p_sigmask, &sss);
+		bsd_to_svr4_sigset(&td->td_sigmask, &sss);
 		PROC_UNLOCK(td->td_proc);
 		if ((error = copyout(&sss, uap->oset, sizeof(sss))) != 0)
 			return error;
@@ -525,19 +525,19 @@ svr4_sys_sigprocmask(td, uap)
 	PROC_LOCK(td->td_proc);
 	switch (uap->how) {
 	case SVR4_SIG_BLOCK:
-		SIGSETOR(td->td_proc->p_sigmask, bss);
-		SIG_CANTMASK(td->td_proc->p_sigmask);
+		SIGSETOR(td->td_sigmask, bss);
+		SIG_CANTMASK(td->td_sigmask);
 		break;
 
 	case SVR4_SIG_UNBLOCK:
-		SIGSETNAND(td->td_proc->p_sigmask, bss);
-		signotify(td->td_proc);
+		SIGSETNAND(td->td_sigmask, bss);
+		signotify(td);
 		break;
 
 	case SVR4_SIG_SETMASK:
-		td->td_proc->p_sigmask = bss;
-		SIG_CANTMASK(td->td_proc->p_sigmask);
-		signotify(td->td_proc);
+		td->td_sigmask = bss;
+		SIG_CANTMASK(td->td_sigmask);
+		signotify(td);
 		break;
 
 	default:
@@ -566,7 +566,8 @@ svr4_sys_sigpending(td, uap)
 			return 0;
 		PROC_LOCK(td->td_proc);
 		bss = td->td_proc->p_siglist;
-		SIGSETAND(bss, td->td_proc->p_sigmask);
+		SIGSETOR(bss, td->td_siglist);
+		SIGSETAND(bss, td->td_sigmask);
 		PROC_UNLOCK(td->td_proc);
 		bsd_to_svr4_sigset(&bss, &sss);
 		break;
@@ -636,7 +637,7 @@ svr4_sys_context(td, uap)
 	case 0:
 		PROC_LOCK(td->td_proc);
 		DPRINTF(("getcontext(%p)\n", uap->uc));
-		svr4_getcontext(td, &uc, &td->td_proc->p_sigmask,
+		svr4_getcontext(td, &uc, &td->td_sigmask,
 		    sigonstack(cpu_getstack(td)));
 		PROC_UNLOCK(td->td_proc);
 		return copyout(&uc, uap->uc, sizeof(uc));
@@ -671,6 +672,6 @@ svr4_sys_pause(td, uap)
 {
 	struct sigsuspend_args bsa;
 
-	bsa.sigmask = &td->td_proc->p_sigmask;
+	bsa.sigmask = &td->td_sigmask;
 	return sigsuspend(td, &bsa);
 }
diff --git a/sys/fs/coda/coda_psdev.c b/sys/fs/coda/coda_psdev.c
index 392012b..ef237c4 100644
--- a/sys/fs/coda/coda_psdev.c
+++ b/sys/fs/coda/coda_psdev.c
@@ -548,7 +548,7 @@ coda_call(mntinfo, inSize, outSize, buffer)
 	 */
 	i = 0;
 	PROC_LOCK(p);
-	psig_omask = p->p_sigmask;
+	psig_omask = td->td_sigmask;
 	do {
 		error = msleep(&vmp->vm_sleep, &p->p_mtx,
 			       (coda_call_sleep|coda_pcatch), "coda_call",
@@ -563,8 +563,8 @@ coda_call(mntinfo, inSize, outSize, buffer)
 		else {
 			SIGEMPTYSET(tempset);
 			SIGADDSET(tempset, SIGIO);
-			if (SIGSETEQ(p->p_siglist, tempset)) {
-				SIGADDSET(p->p_sigmask, SIGIO);
+			if (SIGSETEQ(td->td_siglist, tempset)) {
+				SIGADDSET(td->td_sigmask, SIGIO);
 #ifdef	CODA_VERBOSE
 				printf("coda_call: tsleep returns %d SIGIO, cnt %d\n",
 				       error, i);
@@ -572,8 +572,8 @@ coda_call(mntinfo, inSize, outSize, buffer)
 			} else {
 				SIGDELSET(tempset, SIGIO);
 				SIGADDSET(tempset, SIGALRM);
-				if (SIGSETEQ(p->p_siglist, tempset)) {
-					SIGADDSET(p->p_sigmask, SIGALRM);
+				if (SIGSETEQ(td->td_siglist, tempset)) {
+					SIGADDSET(td->td_sigmask, SIGALRM);
 #ifdef	CODA_VERBOSE
 					printf("coda_call: tsleep returns %d SIGALRM, cnt %d\n",
 					       error, i);
@@ -584,25 +584,25 @@ coda_call(mntinfo, inSize, outSize, buffer)
 					       error, i);
 
 #if notyet
-					tempset = p->p_siglist;
-					SIGSETNAND(tempset, p->p_sigmask);
+					tempset = td->td_siglist;
+					SIGSETNAND(tempset, td->td_sigmask);
 					printf("coda_call: siglist = %p, sigmask = %p, mask %p\n",
-					       p->p_siglist, p->p_sigmask,
+					       td->td_siglist, td->td_sigmask,
 					       tempset);
 					break;
-					SIGSETOR(p->p_sigmask, p->p_siglist);
-					tempset = p->p_siglist;
-					SIGSETNAND(tempset, p->p_sigmask);
+					SIGSETOR(td->td_sigmask, td->td_siglist);
+					tempset = td->td_siglist;
+					SIGSETNAND(tempset, td->td_sigmask);
 					printf("coda_call: new mask, siglist = %p, sigmask = %p, mask %p\n",
-					       p->p_siglist, p->p_sigmask,
+					       td->td_siglist, td->td_sigmask,
 					       tempset);
 #endif
 				}
 			}
 		}
 	} while (error && i++ < 128 && VC_OPEN(vcp));
-	p->p_sigmask = psig_omask;
-	signotify(p);
+	td->td_sigmask = psig_omask;
+	signotify(td);
 	PROC_UNLOCK(p);
 #else
 	(void) tsleep(&vmp->vm_sleep, coda_call_sleep, "coda_call", 0);
diff --git a/sys/i386/i386/machdep.c b/sys/i386/i386/machdep.c
index 9a1cf43..b389828 100644
--- a/sys/i386/i386/machdep.c
+++ b/sys/i386/i386/machdep.c
@@ -751,9 +751,9 @@ osigreturn(td, uap)
 	else
 		p->p_sigstk.ss_flags &= ~SS_ONSTACK;
 #endif
-	SIGSETOLD(p->p_sigmask, scp->sc_mask);
-	SIG_CANTMASK(p->p_sigmask);
-	signotify(p);
+	SIGSETOLD(td->td_sigmask, scp->sc_mask);
+	SIG_CANTMASK(td->td_sigmask);
+	signotify(td);
 	PROC_UNLOCK(p);
 	return (EJUSTRETURN);
 }
@@ -859,9 +859,9 @@ freebsd4_sigreturn(td, uap)
 		p->p_sigstk.ss_flags &= ~SS_ONSTACK;
 #endif
 
-	p->p_sigmask = ucp->uc_sigmask;
-	SIG_CANTMASK(p->p_sigmask);
-	signotify(p);
+	td->td_sigmask = ucp->uc_sigmask;
+	SIG_CANTMASK(td->td_sigmask);
+	signotify(td);
 	PROC_UNLOCK(p);
 	return (EJUSTRETURN);
 }
@@ -969,9 +969,9 @@ sigreturn(td, uap)
 		p->p_sigstk.ss_flags &= ~SS_ONSTACK;
 #endif
 
-	p->p_sigmask = ucp->uc_sigmask;
-	SIG_CANTMASK(p->p_sigmask);
-	signotify(p);
+	td->td_sigmask = ucp->uc_sigmask;
+	SIG_CANTMASK(td->td_sigmask);
+	signotify(td);
 	PROC_UNLOCK(p);
 	return (EJUSTRETURN);
 }
diff --git a/sys/i386/ibcs2/ibcs2_signal.c b/sys/i386/ibcs2/ibcs2_signal.c
index 3a6082e..fac52bc 100644
--- a/sys/i386/ibcs2/ibcs2_signal.c
+++ b/sys/i386/ibcs2/ibcs2_signal.c
@@ -324,11 +324,11 @@ ibcs2_sigsys(td, uap)
                         if(IBCS2_SIGCALL(uap->sig) == IBCS2_SIGSET_MASK) {
 				PROC_LOCK(p);
 			        /* check to make sure signal is not blocked */
-                                if(sigismember(&p->p_sigmask, signum)) {
+                                if(sigismember(&td->td_sigmask, signum)) {
 				        /* return SIG_HOLD and unblock signal*/
                                         td->td_retval[0] = (int)IBCS2_SIG_HOLD;
-					SIGDELSET(p->p_sigmask, signum);
-					signotify(p);
+					SIGDELSET(td->td_sigmask, signum);
+					signotify(td);
 				}
 				PROC_UNLOCK(p);
 			}
@@ -377,7 +377,7 @@ ibcs2_sigsys(td, uap)
 			struct sigsuspend_args sa;
 
 			PROC_LOCK(p);
-			mask = p->p_sigmask;
+			mask = td->td_sigmask;
 			PROC_UNLOCK(p);
 			SIGDELSET(mask, signum);
 			sa.sigmask = &mask;
@@ -402,7 +402,7 @@ ibcs2_sigprocmask(td, uap)
 	if (uap->oset != NULL) {
 		/* Fix the return value first if needed */
 		PROC_LOCK(p);
-		bsd_to_ibcs2_sigset(&p->p_sigmask, &iss);
+		bsd_to_ibcs2_sigset(&td->td_sigmask, &iss);
 		PROC_UNLOCK(p);
 		if ((error = copyout(&iss, uap->oset, sizeof(iss))) != 0)
 			return error;
@@ -421,19 +421,19 @@ ibcs2_sigprocmask(td, uap)
 
 	switch (uap->how) {
 	case IBCS2_SIG_BLOCK:
-		SIGSETOR(p->p_sigmask, bss);
-		SIG_CANTMASK(p->p_sigmask);
+		SIGSETOR(td->td_sigmask, bss);
+		SIG_CANTMASK(td->td_sigmask);
 		break;
 
 	case IBCS2_SIG_UNBLOCK:
-		SIGSETNAND(p->p_sigmask, bss);
-		signotify(p);
+		SIGSETNAND(td->td_sigmask, bss);
+		signotify(td);
 		break;
 
 	case IBCS2_SIG_SETMASK:
-		p->p_sigmask = bss;
-		SIG_CANTMASK(p->p_sigmask);
-		signotify(p);
+		td->td_sigmask = bss;
+		SIG_CANTMASK(td->td_sigmask);
+		signotify(td);
 		break;
 
 	default:
@@ -456,8 +456,9 @@ ibcs2_sigpending(td, uap)
 	ibcs2_sigset_t iss;
 
 	PROC_LOCK(p);
-	bss = p->p_siglist;
-	SIGSETAND(bss, p->p_sigmask);
+	bss = td->td_siglist;
+	SIGSETOR(bss, p->p_siglist);
+	SIGSETAND(bss, td->td_sigmask);
 	PROC_UNLOCK(p);
 	bsd_to_ibcs2_sigset(&bss, &iss);
 
@@ -492,7 +493,7 @@ ibcs2_pause(td, uap)
 	struct sigsuspend_args sa;
 
 	PROC_LOCK(p);
-	mask = td->td_proc->p_sigmask;
+	mask = td->td_sigmask;
 	PROC_UNLOCK(p);
 	sa.sigmask = &mask;
 	return sigsuspend(td, &sa);
diff --git a/sys/i386/linux/linux_machdep.c b/sys/i386/linux/linux_machdep.c
index c1aaa76..6eb0e5c 100644
--- a/sys/i386/linux/linux_machdep.c
+++ b/sys/i386/linux/linux_machdep.c
@@ -772,7 +772,7 @@ linux_pause(struct thread *td, struct linux_pause_args *args)
 #endif
 
 	PROC_LOCK(p);
-	sigmask = p->p_sigmask;
+	sigmask = td->td_sigmask;
 	PROC_UNLOCK(p);
 	return (kern_sigsuspend(td, sigmask));
 }
diff --git a/sys/i386/linux/linux_sysvec.c b/sys/i386/linux/linux_sysvec.c
index 017a2e0..ec98a93 100644
--- a/sys/i386/linux/linux_sysvec.c
+++ b/sys/i386/linux/linux_sysvec.c
@@ -562,9 +562,9 @@ linux_sigreturn(struct thread *td, struct linux_sigreturn_args *args)
 	for (i = 0; i < (LINUX_NSIG_WORDS-1); i++)
 		lmask.__bits[i+1] = frame.sf_extramask[i];
 	PROC_LOCK(p);
-	linux_to_bsd_sigset(&lmask, &p->p_sigmask);
-	SIG_CANTMASK(p->p_sigmask);
-	signotify(p);
+	linux_to_bsd_sigset(&lmask, &td->td_sigmask);
+	SIG_CANTMASK(td->td_sigmask);
+	signotify(td);
 	PROC_UNLOCK(p);
 
 	/*
@@ -657,9 +657,9 @@ linux_rt_sigreturn(struct thread *td, struct linux_rt_sigreturn_args *args)
 	}
 
 	PROC_LOCK(p);
-	linux_to_bsd_sigset(&uc.uc_sigmask, &p->p_sigmask);
-	SIG_CANTMASK(p->p_sigmask);
-	signotify(p);
+	linux_to_bsd_sigset(&uc.uc_sigmask, &td->td_sigmask);
+	SIG_CANTMASK(td->td_sigmask);
+	signotify(td);
 	PROC_UNLOCK(p);
 
 	/*
diff --git a/sys/i386/svr4/svr4_machdep.c b/sys/i386/svr4/svr4_machdep.c
index bf8aecb..848ceb9 100644
--- a/sys/i386/svr4/svr4_machdep.c
+++ b/sys/i386/svr4/svr4_machdep.c
@@ -293,8 +293,8 @@ svr4_setcontext(td, uc)
 #endif
 		svr4_to_bsd_sigset(&uc->uc_sigmask, &mask);
 		SIG_CANTMASK(mask);
-		p->p_sigmask = mask;
-		signotify(p);
+		td->td_sigmask = mask;
+		signotify(td);
 	}
 	PROC_UNLOCK(p);
 
diff --git a/sys/ia64/ia64/machdep.c b/sys/ia64/ia64/machdep.c
index 57e86c3..bdc8dca 100644
--- a/sys/ia64/ia64/machdep.c
+++ b/sys/ia64/ia64/machdep.c
@@ -988,9 +988,9 @@ sigreturn(struct thread *td,
 		p->p_sigstk.ss_flags &= ~SS_ONSTACK;
 #endif
 
-	p->p_sigmask = uc.uc_sigmask;
-	SIG_CANTMASK(p->p_sigmask);
-	signotify(p);
+	td->td_sigmask = uc.uc_sigmask;
+	SIG_CANTMASK(td->td_sigmask);
+	signotify(td);
 	PROC_UNLOCK(p);
 
 	/* XXX ksc.sc_ownedfp ? */
diff --git a/sys/kern/kern_context.c b/sys/kern/kern_context.c
index 1cc0eac..d1b657f 100644
--- a/sys/kern/kern_context.c
+++ b/sys/kern/kern_context.c
@@ -73,7 +73,7 @@ getcontext(struct thread *td, struct getcontext_args *uap)
 		ret = EINVAL;
 	else {
 		get_mcontext(td, &uc.uc_mcontext);
-		uc.uc_sigmask = td->td_proc->p_sigmask;
+		uc.uc_sigmask = td->td_sigmask;
 		ret = copyout(&uc, uap->ucp, UC_COPY_SIZE);
 	}
 	return (ret);
@@ -97,7 +97,7 @@ setcontext(struct thread *td, struct setcontext_args *uap)
 			if (ret == 0) {
 				SIG_CANTMASK(uc.uc_sigmask);
 				PROC_LOCK(td->td_proc);
-				td->td_proc->p_sigmask = uc.uc_sigmask;
+				td->td_sigmask = uc.uc_sigmask;
 				PROC_UNLOCK(td->td_proc);
 			}
 		}
@@ -115,7 +115,7 @@ swapcontext(struct thread *td, struct swapcontext_args *uap)
 		ret = EINVAL;
 	else {
 		get_mcontext(td, &uc.uc_mcontext);
-		uc.uc_sigmask = td->td_proc->p_sigmask;
+		uc.uc_sigmask = td->td_sigmask;
 		ret = copyout(&uc, uap->oucp, UC_COPY_SIZE);
 		if (ret == 0) {
 			ret = copyin(uap->ucp, &uc, UC_COPY_SIZE);
@@ -124,7 +124,7 @@ swapcontext(struct thread *td, struct swapcontext_args *uap)
 				if (ret == 0) {
 					SIG_CANTMASK(uc.uc_sigmask);
 					PROC_LOCK(td->td_proc);
-					td->td_proc->p_sigmask = uc.uc_sigmask;
+					td->td_sigmask = uc.uc_sigmask;
 					PROC_UNLOCK(td->td_proc);
 				}
 			}
diff --git a/sys/kern/kern_exit.c b/sys/kern/kern_exit.c
index c6cb858..dd537b2 100644
--- a/sys/kern/kern_exit.c
+++ b/sys/kern/kern_exit.c
@@ -217,6 +217,7 @@ exit1(struct thread *td, int rv)
 	stopprofclock(p);
 	p->p_flag &= ~(P_TRACED | P_PPWAIT);
 	SIGEMPTYSET(p->p_siglist);
+	SIGEMPTYSET(td->td_siglist);
 	if (timevalisset(&p->p_realtimer.it_value))
 		callout_stop(&p->p_itcallout);
 	PROC_UNLOCK(p);
diff --git a/sys/kern/kern_kse.c b/sys/kern/kern_kse.c
index 149b268..b9c85f8 100644
--- a/sys/kern/kern_kse.c
+++ b/sys/kern/kern_kse.c
@@ -496,8 +496,10 @@ kse_release(struct thread *td, struct kse_release_args *uap)
 	mtx_lock_spin(&sched_lock);
 	/* Change OURSELF to become an upcall. */
 	td->td_flags = TDF_UPCALLING;
+#if 0	/* XXX This shouldn't be necessary */
 	if (p->p_sflag & PS_NEEDSIGCHK)
 		td->td_flags |= TDF_ASTPENDING;
+#endif
 	mtx_unlock_spin(&sched_lock);
 	PROC_LOCK(p);
 	while ((td->td_upcall->ku_flags & KUF_DOUPCALL) == 0 &&
@@ -744,7 +746,7 @@ thread_getcontext(struct thread *td, ucontext_t *uc)
 #ifdef __i386__
 	get_mcontext(td, &uc->uc_mcontext);
 #endif
-	uc->uc_sigmask = td->td_proc->p_sigmask;
+	uc->uc_sigmask = td->td_sigmask;
 }
 
 /*
@@ -769,7 +771,7 @@ thread_setcontext(struct thread *td, ucontext_t *uc)
 	if (ret == 0) {
 		SIG_CANTMASK(uc->uc_sigmask);
 		PROC_LOCK(td->td_proc);
-		td->td_proc->p_sigmask = uc->uc_sigmask;
+		td->td_sigmask = uc->uc_sigmask;
 		PROC_UNLOCK(td->td_proc);
 	}
 	return (ret);
@@ -1247,6 +1249,7 @@ thread_exit(void)
 	} else {
 		PROC_UNLOCK(p);
 	}
+	/* XXX Shouldn't cpu_throw() here. */
 	cpu_throw();
 	/* NOTREACHED */
 }
@@ -1428,8 +1431,10 @@ thread_schedule_upcall(struct thread *td, struct kse_upcall *ku)
 	ku->ku_owner   = td2;
 	td2->td_upcall = ku;
 	td2->td_flags  = TDF_UPCALLING;
+#if 0	/* XXX This shouldn't be necessary */
 	if (td->td_proc->p_sflag & PS_NEEDSIGCHK)
 		td2->td_flags |= TDF_ASTPENDING;
+#endif
 	td2->td_kse    = NULL;
 	td2->td_state  = TDS_CAN_RUN;
 	td2->td_inhibitors = 0;
@@ -1593,6 +1598,7 @@ thread_userret(struct thread *td, struct trapframe *frame)
 	p = td->td_proc;
 	kg = td->td_ksegrp;
 
+	
 	/* Nothing to do with non-threaded group/process */
 	if (td->td_ksegrp->kg_numupcalls == 0)
 		return (0);
@@ -1621,12 +1627,12 @@ thread_userret(struct thread *td, struct trapframe *frame)
 	if (TD_CAN_UNBIND(td)) {
 		mtx_lock_spin(&sched_lock);
 		td->td_flags &= ~TDF_CAN_UNBIND;
-		mtx_unlock_spin(&sched_lock);
 		ku = td->td_upcall;
-		if ((p->p_sflag & PS_NEEDSIGCHK) == 0 &&
+		if ((td->td_flags & TDF_NEEDSIGCHK) == 0 &&
 		    (kg->kg_completed == NULL) &&
 		    (ku->ku_flags & KUF_DOUPCALL) == 0 &&
 		    (kg->kg_upquantum && ticks >= kg->kg_nextupcall)) {
+			mtx_unlock_spin(&sched_lock);
 			thread_update_usr_ticks(td, 0);
 			nanotime(&ts);
 			error = copyout(&ts,
@@ -1637,6 +1643,7 @@ thread_userret(struct thread *td, struct trapframe *frame)
 				goto out;
 			return (0);
 		}
+		mtx_unlock_spin(&sched_lock);
 		error = thread_export_context(td);
 		if (error) {
 			/*
diff --git a/sys/kern/kern_proc.c b/sys/kern/kern_proc.c
index 752fbf0..26fb2b7 100644
--- a/sys/kern/kern_proc.c
+++ b/sys/kern/kern_proc.c
@@ -610,12 +610,15 @@ fill_kinfo_proc(p, kp)
 	struct kinfo_proc *kp;
 {
 	struct thread *td;
+	struct thread *td0;
 	struct kse *ke;
 	struct ksegrp *kg;
 	struct tty *tp;
 	struct session *sp;
 	struct timeval tv;
 
+	td = FIRST_THREAD_IN_PROC(p);
+
 	bzero(kp, sizeof(*kp));
 
 	kp->ki_structsize = sizeof(*kp);
@@ -657,7 +660,7 @@ fill_kinfo_proc(p, kp)
 		kp->ki_rssize = vmspace_resident_count(vm); /*XXX*/
 		if (p->p_sflag & PS_INMEM)
 			kp->ki_rssize += UAREA_PAGES;
-		FOREACH_THREAD_IN_PROC(p, td) /* XXXKSE: thread swapout check */
+		FOREACH_THREAD_IN_PROC(p, td0)/* XXXKSE: thread swapout check */
 			kp->ki_rssize += KSTACK_PAGES;
 		kp->ki_swrss = vm->vm_swrss;
 		kp->ki_tsize = vm->vm_tsize;
@@ -673,7 +676,6 @@ fill_kinfo_proc(p, kp)
 		    p->p_stats->p_cru.ru_stime.tv_usec;
 	}
 	if (p->p_state != PRS_ZOMBIE) {
-		td = FIRST_THREAD_IN_PROC(p);
 		if (td == NULL) {
 			/* XXXKSE: This should never happen. */
 			printf("fill_kinfo_proc(): pid %d has no threads!\n",
@@ -786,7 +788,8 @@ fill_kinfo_proc(p, kp)
 		strlcpy(kp->ki_ocomm, p->p_comm, sizeof(kp->ki_ocomm));
 	}
 	kp->ki_siglist = p->p_siglist;
-	kp->ki_sigmask = p->p_sigmask;
+        SIGSETOR(kp->ki_siglist, td->td_siglist);
+	kp->ki_sigmask = td->td_sigmask;
 	kp->ki_xstat = p->p_xstat;
 	kp->ki_acflag = p->p_acflag;
 	kp->ki_flag = p->p_flag;
diff --git a/sys/kern/kern_sig.c b/sys/kern/kern_sig.c
index b5db78c..ee2b7ec 100644
--- a/sys/kern/kern_sig.c
+++ b/sys/kern/kern_sig.c
@@ -80,17 +80,15 @@
 #define	ONSIG	32		/* NSIG for osig* syscalls.  XXX. */
 
 static int	coredump(struct thread *);
-static int	do_sigprocmask(struct proc *p, int how, sigset_t *set,
-			sigset_t *oset, int old);
 static char	*expand_name(const char *, uid_t, pid_t);
 static int	killpg1(struct thread *td, int sig, int pgid, int all);
-static int	sig_ffs(sigset_t *set);
 static int	sigprop(int sig);
 static void	stop(struct proc *);
-static void	tdsignal(struct thread *td, int sig, sig_t action);
+static void	tdsigwakeup(struct thread *td, int sig, sig_t action);
 static int	filt_sigattach(struct knote *kn);
 static void	filt_sigdetach(struct knote *kn);
 static int	filt_signal(struct knote *kn, long hint);
+static struct thread *sigtd(struct proc *p, int sig, int prop);
 
 struct filterops sig_filtops =
 	{ 0, filt_sigattach, filt_sigdetach, filt_signal };
@@ -183,31 +181,36 @@ cursig(struct thread *td)
 
 	PROC_LOCK_ASSERT(p, MA_OWNED);
 	mtx_assert(&sched_lock, MA_NOTOWNED);
-	return (SIGPENDING(p) ? issignal(td) : 0);
+	return (SIGPENDING(td) ? issignal(td) : 0);
 }
 
 /*
  * Arrange for ast() to handle unmasked pending signals on return to user
- * mode.  This must be called whenever a signal is added to p_siglist or
- * unmasked in p_sigmask.
+ * mode.  This must be called whenever a signal is added to td_siglist or
+ * unmasked in td_sigmask.
  */
 void
-signotify(struct proc *p)
+signotify(struct thread *td)
 {
-	struct thread *td;
-	struct ksegrp *kg;
+	struct proc *p;
+	sigset_t set;
+
+	p = td->td_proc;
 
 	PROC_LOCK_ASSERT(p, MA_OWNED);
+
+	/*
+	 * If our mask changed we may have to move signal that were
+	 * previously masked by all threads to our siglist.
+	 */
+	set = p->p_siglist;
+	SIGSETNAND(set, td->td_sigmask);
+	SIGSETNAND(p->p_siglist, set);
+	SIGSETOR(td->td_siglist, set);
+
 	mtx_lock_spin(&sched_lock);
-	if (SIGPENDING(p)) {
-		p->p_sflag |= PS_NEEDSIGCHK;
-		/* XXXKSE for now punish all KSEs */
-		FOREACH_KSEGRP_IN_PROC(p, kg) {
-			FOREACH_THREAD_IN_GROUP(kg, td) {
-				td->td_flags |= TDF_ASTPENDING;	
-			}
-		}
-	}
+	if (SIGPENDING(td))
+		td->td_flags |= TDF_NEEDSIGCHK | TDF_ASTPENDING;
 	mtx_unlock_spin(&sched_lock);
 }
 
@@ -220,7 +223,7 @@ sigprop(int sig)
 	return (0);
 }
 
-static __inline int
+int
 sig_ffs(sigset_t *set)
 {
 	int i;
@@ -245,6 +248,7 @@ kern_sigaction(td, sig, act, oact, flags)
 	int flags;
 {
 	register struct sigacts *ps;
+	struct thread *td0;
 	struct proc *p = td->td_proc;
 
 	if (!_SIG_VALID(sig))
@@ -348,6 +352,8 @@ kern_sigaction(td, sig, act, oact, flags)
 		     ps->ps_sigact[_SIG_IDX(sig)] == SIG_DFL)) {
 			/* never to be seen again */
 			SIGDELSET(p->p_siglist, sig);
+			FOREACH_THREAD_IN_PROC(p, td0)
+				SIGDELSET(td0->td_siglist, sig);
 			if (sig != SIGCONT)
 				/* easier in psignal */
 				SIGADDSET(p->p_sigignore, sig);
@@ -542,7 +548,7 @@ execsigs(p)
 
 	/*
 	 * Reset caught signals.  Held signals remain held
-	 * through p_sigmask (unless they were caught,
+	 * through td_sigmask (unless they were caught,
 	 * and are now ignored by default).
 	 */
 	PROC_LOCK_ASSERT(p, MA_OWNED);
@@ -554,10 +560,18 @@ execsigs(p)
 			if (sig != SIGCONT)
 				SIGADDSET(p->p_sigignore, sig);
 			SIGDELSET(p->p_siglist, sig);
+			/*
+			 * There is only one thread at this point.
+			 */
+			SIGDELSET(FIRST_THREAD_IN_PROC(p)->td_siglist, sig);
 		}
 		ps->ps_sigact[_SIG_IDX(sig)] = SIG_DFL;
 	}
 	/*
+	 * Clear out the td's sigmask.  Normal processes use the proc sigmask.
+	 */
+	SIGEMPTYSET(FIRST_THREAD_IN_PROC(p)->td_sigmask);
+	/*
 	 * Reset stack state to the user stack.
 	 * Clear set of signals caught on the signal stack.
 	 */
@@ -578,44 +592,44 @@ execsigs(p)
  *
  *	Manipulate signal mask.
  */
-static int
-do_sigprocmask(p, how, set, oset, old)
-	struct proc *p;
+int
+do_sigprocmask(td, how, set, oset, old)
+	struct thread *td;
 	int how;
 	sigset_t *set, *oset;
 	int old;
 {
 	int error;
 
-	PROC_LOCK(p);
+	PROC_LOCK(td->td_proc);
 	if (oset != NULL)
-		*oset = p->p_sigmask;
+		*oset = td->td_sigmask;
 
 	error = 0;
 	if (set != NULL) {
 		switch (how) {
 		case SIG_BLOCK:
 			SIG_CANTMASK(*set);
-			SIGSETOR(p->p_sigmask, *set);
+			SIGSETOR(td->td_sigmask, *set);
 			break;
 		case SIG_UNBLOCK:
-			SIGSETNAND(p->p_sigmask, *set);
-			signotify(p);
+			SIGSETNAND(td->td_sigmask, *set);
+			signotify(td);
 			break;
 		case SIG_SETMASK:
 			SIG_CANTMASK(*set);
 			if (old)
-				SIGSETLO(p->p_sigmask, *set);
+				SIGSETLO(td->td_sigmask, *set);
 			else
-				p->p_sigmask = *set;
-			signotify(p);
+				td->td_sigmask = *set;
+			signotify(td);
 			break;
 		default:
 			error = EINVAL;
 			break;
 		}
 	}
-	PROC_UNLOCK(p);
+	PROC_UNLOCK(td->td_proc);
 	return (error);
 }
 
@@ -635,7 +649,6 @@ sigprocmask(td, uap)
 	register struct thread *td;
 	struct sigprocmask_args *uap;
 {
-	struct proc *p = td->td_proc;
 	sigset_t set, oset;
 	sigset_t *setp, *osetp;
 	int error;
@@ -647,7 +660,7 @@ sigprocmask(td, uap)
 		if (error)
 			return (error);
 	}
-	error = do_sigprocmask(p, uap->how, setp, osetp, 0);
+	error = do_sigprocmask(td, uap->how, setp, osetp, 0);
 	if (osetp && !error) {
 		error = copyout(osetp, uap->oset, sizeof(oset));
 	}
@@ -669,12 +682,11 @@ osigprocmask(td, uap)
 	register struct thread *td;
 	struct osigprocmask_args *uap;
 {
-	struct proc *p = td->td_proc;
 	sigset_t set, oset;
 	int error;
 
 	OSIG2SIG(uap->mask, set);
-	error = do_sigprocmask(p, uap->how, &set, &oset, 1);
+	error = do_sigprocmask(td, uap->how, &set, &oset, 1);
 	SIG2OSIG(oset, td->td_retval[0]);
 	return (error);
 }
@@ -698,6 +710,7 @@ sigpending(td, uap)
 
 	PROC_LOCK(p);
 	siglist = p->p_siglist;
+	SIGSETOR(siglist, td->td_siglist);
 	PROC_UNLOCK(p);
 	return (copyout(&siglist, uap->set, sizeof(sigset_t)));
 }
@@ -717,9 +730,12 @@ osigpending(td, uap)
 	struct osigpending_args *uap;
 {
 	struct proc *p = td->td_proc;
+	sigset_t siglist;
 
 	PROC_LOCK(p);
-	SIG2OSIG(p->p_siglist, td->td_retval[0]);
+	siglist = p->p_siglist;
+	SIGSETOR(siglist, td->td_siglist);
+	SIG2OSIG(siglist, td->td_retval[0]);
 	PROC_UNLOCK(p);
 	return (0);
 }
@@ -803,8 +819,8 @@ osigblock(td, uap)
 	SIG_CANTMASK(set);
 	mtx_lock(&Giant);
 	PROC_LOCK(p);
-	SIG2OSIG(p->p_sigmask, td->td_retval[0]);
-	SIGSETOR(p->p_sigmask, set);
+	SIG2OSIG(td->td_sigmask, td->td_retval[0]);
+	SIGSETOR(td->td_sigmask, set);
 	PROC_UNLOCK(p);
 	mtx_unlock(&Giant);
 	return (0);
@@ -830,9 +846,9 @@ osigsetmask(td, uap)
 	SIG_CANTMASK(set);
 	mtx_lock(&Giant);
 	PROC_LOCK(p);
-	SIG2OSIG(p->p_sigmask, td->td_retval[0]);
-	SIGSETLO(p->p_sigmask, set);
-	signotify(p);
+	SIG2OSIG(td->td_sigmask, td->td_retval[0]);
+	SIGSETLO(td->td_sigmask, set);
+	signotify(td);
 	PROC_UNLOCK(p);
 	mtx_unlock(&Giant);
 	return (0);
@@ -886,12 +902,13 @@ kern_sigsuspend(struct thread *td, sigset_t mask)
 	mtx_lock(&Giant);
 	PROC_LOCK(p);
 	ps = p->p_sigacts;
-	p->p_oldsigmask = p->p_sigmask;
-	p->p_flag |= P_OLDMASK;
-
+	td->td_oldsigmask = td->td_sigmask;
+	mtx_lock_spin(&sched_lock);
+	td->td_flags |= TDF_OLDMASK;
+	mtx_unlock_spin(&sched_lock);
 	SIG_CANTMASK(mask);
-	p->p_sigmask = mask;
-	signotify(p);
+	td->td_sigmask = mask;
+	signotify(td);
 	while (msleep(ps, &p->p_mtx, PPAUSE|PCATCH, "pause", 0) == 0)
 		/* void */;
 	PROC_UNLOCK(p);
@@ -922,12 +939,14 @@ osigsuspend(td, uap)
 	mtx_lock(&Giant);
 	PROC_LOCK(p);
 	ps = p->p_sigacts;
-	p->p_oldsigmask = p->p_sigmask;
-	p->p_flag |= P_OLDMASK;
+	td->td_oldsigmask = td->td_sigmask;
+	mtx_lock_spin(&sched_lock);
+	td->td_flags |= TDF_OLDMASK;
+	mtx_unlock_spin(&sched_lock);
 	OSIG2SIG(uap->mask, mask);
 	SIG_CANTMASK(mask);
-	SIGSETLO(p->p_sigmask, mask);
-	signotify(p);
+	SIGSETLO(td->td_sigmask, mask);
+	signotify(td);
 	while (msleep(ps, &p->p_mtx, PPAUSE|PCATCH, "opause", 0) == 0)
 		/* void */;
 	PROC_UNLOCK(p);
@@ -1274,18 +1293,18 @@ trapsignal(struct thread *td, int sig, u_long code)
 	PROC_LOCK(p);
 	ps = p->p_sigacts;
 	if ((p->p_flag & P_TRACED) == 0 && SIGISMEMBER(p->p_sigcatch, sig) &&
-	    !SIGISMEMBER(p->p_sigmask, sig)) {
+	    !SIGISMEMBER(td->td_sigmask, sig)) {
 		p->p_stats->p_ru.ru_nsignals++;
 #ifdef KTRACE
 		if (KTRPOINT(curthread, KTR_PSIG))
 			ktrpsig(sig, ps->ps_sigact[_SIG_IDX(sig)],
-			    &p->p_sigmask, code);
+			    &td->td_sigmask, code);
 #endif
 		(*p->p_sysent->sv_sendsig)(ps->ps_sigact[_SIG_IDX(sig)], sig,
-						&p->p_sigmask, code);
-		SIGSETOR(p->p_sigmask, ps->ps_catchmask[_SIG_IDX(sig)]);
+						&td->td_sigmask, code);
+		SIGSETOR(td->td_sigmask, ps->ps_catchmask[_SIG_IDX(sig)]);
 		if (!SIGISMEMBER(ps->ps_signodefer, sig))
-			SIGADDSET(p->p_sigmask, sig);
+			SIGADDSET(td->td_sigmask, sig);
 		if (SIGISMEMBER(ps->ps_sigreset, sig)) {
 			/*
 			 * See kern_sigaction() for origin of this code.
@@ -1299,11 +1318,45 @@ trapsignal(struct thread *td, int sig, u_long code)
 	} else {
 		p->p_code = code;	/* XXX for core dump/debugger */
 		p->p_sig = sig;		/* XXX to verify code */
-		psignal(p, sig);
+		tdsignal(td, sig);
 	}
 	PROC_UNLOCK(p);
 }
 
+static struct thread *
+sigtd(struct proc *p, int sig, int prop)
+{
+	struct thread *td;
+
+	PROC_LOCK_ASSERT(p, MA_OWNED);
+
+	/*
+	 * If we know the signal is bound for a specific thread then we
+	 * assume that we are in that threads context.  This is the case
+	 * for SIGXCPU, SIGILL, etc.  Otherwise someone did a kill() from
+	 * userland and the real thread doesn't actually matter.
+	 */
+	if ((prop & SA_PROC) != 0 && curthread->td_proc == p)
+		return (curthread);
+
+	/*
+	 * We should search for the first thread that is blocked in
+	 * sigsuspend with this signal unmasked.
+	 */
+
+	/* XXX */
+
+	/*
+	 * Find the first thread in the proc that doesn't have this signal
+	 * masked.
+	 */
+	FOREACH_THREAD_IN_PROC(p, td)
+		if (!SIGISMEMBER(td->td_sigmask, sig))
+			return (td);
+
+	return (FIRST_THREAD_IN_PROC(p));
+}
+
 /*
  * Send the signal to the process.  If the signal has an action, the action
  * is usually performed by the target process rather than the caller; we add
@@ -1318,22 +1371,51 @@ trapsignal(struct thread *td, int sig, u_long code)
  * Other ignored signals are discarded immediately.
  */
 void
-psignal(p, sig)
-	register struct proc *p;
-	register int sig;
+psignal(struct proc *p, int sig)
 {
-	register sig_t action;
 	struct thread *td;
+	int prop;
+
+	PROC_LOCK_ASSERT(p, MA_OWNED);
+	prop = sigprop(sig);
+
+	/*
+	 * Find a thread to deliver the signal to.
+	 */
+	td = sigtd(p, sig, prop);
+
+	tdsignal(td, sig);
+}
+
+void
+tdsignal(struct thread *td, int sig)
+{
+	struct proc *p;
+	register sig_t action;
+	sigset_t *siglist;
+	struct thread *td0;
 	register int prop;
 
 
 	KASSERT(_SIG_VALID(sig),
-	    ("psignal(): invalid signal %d\n", sig));
+	    ("tdsignal(): invalid signal %d\n", sig));
+
+	p = td->td_proc;
 
 	PROC_LOCK_ASSERT(p, MA_OWNED);
 	KNOTE(&p->p_klist, NOTE_SIGNAL | sig);
 
 	prop = sigprop(sig);
+
+	/*
+	 * If this thread is blocking this signal then we'll leave it in the
+	 * proc so that we can find it in the first thread that unblocks it.
+	 */
+	if (SIGISMEMBER(td->td_sigmask, sig))
+		siglist = &p->p_siglist;
+	else
+		siglist = &td->td_siglist;
+
 	/*
 	 * If proc is traced, always give parent a chance;
 	 * if signal event is tracked by procfs, give *that*
@@ -1351,7 +1433,7 @@ psignal(p, sig)
 		 */
 		if (SIGISMEMBER(p->p_sigignore, sig) || (p->p_flag & P_WEXIT))
 			return;
-		if (SIGISMEMBER(p->p_sigmask, sig))
+		if (SIGISMEMBER(td->td_sigmask, sig))
 			action = SIG_HOLD;
 		else if (SIGISMEMBER(p->p_sigcatch, sig))
 			action = SIG_CATCH;
@@ -1359,8 +1441,15 @@ psignal(p, sig)
 			action = SIG_DFL;
 	}
 
-	if (prop & SA_CONT)
+	if (prop & SA_CONT) {
 		SIG_STOPSIGMASK(p->p_siglist);
+		/*
+		 * XXX Should investigate leaving STOP and CONT sigs only in
+		 * the proc's siglist.
+		 */
+		FOREACH_THREAD_IN_PROC(p, td0)
+			SIG_STOPSIGMASK(td0->td_siglist);
+	}
 
 	if (prop & SA_STOP) {
 		/*
@@ -1374,10 +1463,12 @@ psignal(p, sig)
 		    (action == SIG_DFL))
 		        return;
 		SIG_CONTSIGMASK(p->p_siglist);
+		FOREACH_THREAD_IN_PROC(p, td0)
+			SIG_CONTSIGMASK(td0->td_siglist);
 		p->p_flag &= ~P_CONTINUED;
 	}
-	SIGADDSET(p->p_siglist, sig);
-	signotify(p);			/* uses schedlock */
+	SIGADDSET(*siglist, sig);
+	signotify(td);			/* uses schedlock */
 
 	/*
 	 * Some signals have a process-wide effect and a per-thread
@@ -1414,10 +1505,10 @@ psignal(p, sig)
 		if (prop & SA_CONT) {
 			/*
 			 * If SIGCONT is default (or ignored), we continue the
-			 * process but don't leave the signal in p_siglist as
+			 * process but don't leave the signal in siglist as
 			 * it has no further action.  If SIGCONT is held, we
 			 * continue the process and leave the signal in
-			 * p_siglist.  If the process catches SIGCONT, let it
+			 * siglist.  If the process catches SIGCONT, let it
 			 * handle the signal itself.  If it isn't waiting on
 			 * an event, it goes back to run state.
 			 * Otherwise, process goes back to sleep state.
@@ -1425,7 +1516,7 @@ psignal(p, sig)
 			p->p_flag &= ~P_STOPPED_SIG;
 			p->p_flag |= P_CONTINUED;
 			if (action == SIG_DFL) {
-				SIGDELSET(p->p_siglist, sig);
+				SIGDELSET(*siglist, sig);
 			} else if (action == SIG_CATCH) {
 				/*
 				 * The process wants to catch it so it needs
@@ -1455,7 +1546,7 @@ psignal(p, sig)
 			 * Just make sure the signal STOP bit set.
 			 */
 			p->p_flag |= P_STOPPED_SIG;
-			SIGDELSET(p->p_siglist, sig);
+			SIGDELSET(*siglist, sig);
 			goto out;
 		}
 
@@ -1468,13 +1559,11 @@ psignal(p, sig)
 		 * It may run a bit until it hits a thread_suspend_check().
 		 */
 		mtx_lock_spin(&sched_lock);
-		FOREACH_THREAD_IN_PROC(p, td) {
-			if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR)) {
-				if (td->td_flags & TDF_CVWAITQ)
-					cv_abort(td);
-				else
-					abortsleep(td);
-			}
+		if (TD_ON_SLEEPQ(td) && (td->td_flags & TDF_SINTR)) {
+			if (td->td_flags & TDF_CVWAITQ)
+				cv_abort(td);
+			else
+				abortsleep(td);
 		}
 		mtx_unlock_spin(&sched_lock);
 		goto out;
@@ -1488,8 +1577,7 @@ psignal(p, sig)
 		if ((p->p_flag & P_TRACED) || (action != SIG_DFL) ||
 			!(prop & SA_STOP)) {
 			mtx_lock_spin(&sched_lock);
-			FOREACH_THREAD_IN_PROC(p, td)
-				tdsignal(td, sig, action);
+			tdsigwakeup(td, sig, action);
 			mtx_unlock_spin(&sched_lock);
 			goto out;
 		}
@@ -1499,14 +1587,17 @@ psignal(p, sig)
 			p->p_flag |= P_STOPPED_SIG;
 			p->p_xstat = sig;
 			mtx_lock_spin(&sched_lock);
-			FOREACH_THREAD_IN_PROC(p, td) {
-				if (TD_IS_SLEEPING(td) &&
+			FOREACH_THREAD_IN_PROC(p, td0) {
+				if (TD_IS_SLEEPING(td0) &&
 					(td->td_flags & TDF_SINTR))
-					thread_suspend_one(td);
+					thread_suspend_one(td0);
 			}
 			thread_stopped(p);
-			if (p->p_numthreads == p->p_suspcount)
+			if (p->p_numthreads == p->p_suspcount) {
 				SIGDELSET(p->p_siglist, p->p_xstat);
+				FOREACH_THREAD_IN_PROC(p, td0)
+					SIGDELSET(td0->td_siglist, p->p_xstat);
+			}
 			mtx_unlock_spin(&sched_lock);
 			goto out;
 		} 
@@ -1515,7 +1606,7 @@ psignal(p, sig)
 		/* NOTREACHED */
 	} else {
 		/* Not in "NORMAL" state. discard the signal. */
-		SIGDELSET(p->p_siglist, sig);
+		SIGDELSET(*siglist, sig);
 		goto out;
 	}
 
@@ -1526,8 +1617,7 @@ psignal(p, sig)
 
 runfast:
 	mtx_lock_spin(&sched_lock);
-	FOREACH_THREAD_IN_PROC(p, td)
-		tdsignal(td, sig, action);
+	tdsigwakeup(td, sig, action);
 	thread_unsuspend(p);
 	mtx_unlock_spin(&sched_lock);
 out:
@@ -1541,7 +1631,7 @@ out:
  * out of any sleep it may be in etc.
  */
 static void
-tdsignal(struct thread *td, int sig, sig_t action)
+tdsigwakeup(struct thread *td, int sig, sig_t action)
 {
 	struct proc *p = td->td_proc;
 	register int prop;
@@ -1591,6 +1681,11 @@ tdsignal(struct thread *td, int sig, sig_t action)
 			 */
 			if ((prop & SA_CONT) && action == SIG_DFL) {
 				SIGDELSET(p->p_siglist, sig);
+				/*
+				 * It may be on either list in this state.
+				 * Remove from both for now.
+				 */
+				SIGDELSET(td->td_siglist, sig);
 				return;
 			}
 
@@ -1637,7 +1732,7 @@ issignal(td)
 	struct thread *td;
 {
 	struct proc *p;
-	sigset_t mask;
+	sigset_t sigpending;
 	register int sig, prop;
 
 	p = td->td_proc;
@@ -1647,13 +1742,14 @@ issignal(td)
 	for (;;) {
 		int traced = (p->p_flag & P_TRACED) || (p->p_stops & S_SIG);
 
-		mask = p->p_siglist;
-		SIGSETNAND(mask, p->p_sigmask);
+		sigpending = td->td_siglist;
+		SIGSETNAND(sigpending, td->td_sigmask);
+
 		if (p->p_flag & P_PPWAIT)
-			SIG_STOPSIGMASK(mask);
-		if (SIGISEMPTY(mask))		/* no signal to send */
+			SIG_STOPSIGMASK(sigpending);
+		if (SIGISEMPTY(sigpending))	/* no signal to send */
 			return (0);
-		sig = sig_ffs(&mask);
+		sig = sig_ffs(&sigpending);
 		prop = sigprop(sig);
 
 		_STOPEVENT(p, S_SIG, sig);
@@ -1663,7 +1759,7 @@ issignal(td)
 		 * only if P_TRACED was on when they were posted.
 		 */
 		if (SIGISMEMBER(p->p_sigignore, sig) && (traced == 0)) {
-			SIGDELSET(p->p_siglist, sig);
+			SIGDELSET(td->td_siglist, sig);
 			continue;
 		}
 		if (p->p_flag & P_TRACED && (p->p_flag & P_PPWAIT) == 0) {
@@ -1698,19 +1794,19 @@ issignal(td)
 			 * then it will leave it in p->p_xstat;
 			 * otherwise we just look for signals again.
 			 */
-			SIGDELSET(p->p_siglist, sig);	/* clear old signal */
+			SIGDELSET(td->td_siglist, sig);	/* clear old signal */
 			sig = p->p_xstat;
 			if (sig == 0)
 				continue;
 
 			/*
-			 * Put the new signal into p_siglist.  If the
+			 * Put the new signal into td_siglist.  If the
 			 * signal is being masked, look for other signals.
 			 */
-			SIGADDSET(p->p_siglist, sig);
-			if (SIGISMEMBER(p->p_sigmask, sig))
+			SIGADDSET(td->td_siglist, sig);
+			if (SIGISMEMBER(td->td_sigmask, sig))
 				continue;
-			signotify(p);
+			signotify(td);
 		}
 
 		/*
@@ -1788,7 +1884,7 @@ issignal(td)
 			 */
 			return (sig);
 		}
-		SIGDELSET(p->p_siglist, sig);		/* take the signal! */
+		SIGDELSET(td->td_siglist, sig);		/* take the signal! */
 	}
 	/* NOTREACHED */
 }
@@ -1852,12 +1948,12 @@ postsig(sig)
 
 	PROC_LOCK_ASSERT(p, MA_OWNED);
 	ps = p->p_sigacts;
-	SIGDELSET(p->p_siglist, sig);
+	SIGDELSET(td->td_siglist, sig);
 	action = ps->ps_sigact[_SIG_IDX(sig)];
 #ifdef KTRACE
 	if (KTRPOINT(td, KTR_PSIG))
-		ktrpsig(sig, action, p->p_flag & P_OLDMASK ?
-		    &p->p_oldsigmask : &p->p_sigmask, 0);
+		ktrpsig(sig, action, td->td_flags & TDF_OLDMASK ?
+		    &td->td_oldsigmask : &td->td_sigmask, 0);
 #endif
 	_STOPEVENT(p, S_SIG, sig);
 
@@ -1872,7 +1968,7 @@ postsig(sig)
 		/*
 		 * If we get here, the signal must be caught.
 		 */
-		KASSERT(action != SIG_IGN && !SIGISMEMBER(p->p_sigmask, sig),
+		KASSERT(action != SIG_IGN && !SIGISMEMBER(td->td_sigmask, sig),
 		    ("postsig action"));
 		/*
 		 * Set the new mask value and also defer further
@@ -1883,15 +1979,17 @@ postsig(sig)
 		 * mask from before the sigsuspend is what we want
 		 * restored after the signal processing is completed.
 		 */
-		if (p->p_flag & P_OLDMASK) {
-			returnmask = p->p_oldsigmask;
-			p->p_flag &= ~P_OLDMASK;
+		mtx_lock_spin(&sched_lock);
+		if (td->td_flags & TDF_OLDMASK) {
+			returnmask = td->td_oldsigmask;
+			td->td_flags &= ~TDF_OLDMASK;
 		} else
-			returnmask = p->p_sigmask;
+			returnmask = td->td_sigmask;
+		mtx_unlock_spin(&sched_lock);
 
-		SIGSETOR(p->p_sigmask, ps->ps_catchmask[_SIG_IDX(sig)]);
+		SIGSETOR(td->td_sigmask, ps->ps_catchmask[_SIG_IDX(sig)]);
 		if (!SIGISMEMBER(ps->ps_signodefer, sig))
-			SIGADDSET(p->p_sigmask, sig);
+			SIGADDSET(td->td_sigmask, sig);
 
 		if (SIGISMEMBER(ps->ps_sigreset, sig)) {
 			/*
diff --git a/sys/kern/kern_thread.c b/sys/kern/kern_thread.c
index 149b268..b9c85f8 100644
--- a/sys/kern/kern_thread.c
+++ b/sys/kern/kern_thread.c
@@ -496,8 +496,10 @@ kse_release(struct thread *td, struct kse_release_args *uap)
 	mtx_lock_spin(&sched_lock);
 	/* Change OURSELF to become an upcall. */
 	td->td_flags = TDF_UPCALLING;
+#if 0	/* XXX This shouldn't be necessary */
 	if (p->p_sflag & PS_NEEDSIGCHK)
 		td->td_flags |= TDF_ASTPENDING;
+#endif
 	mtx_unlock_spin(&sched_lock);
 	PROC_LOCK(p);
 	while ((td->td_upcall->ku_flags & KUF_DOUPCALL) == 0 &&
@@ -744,7 +746,7 @@ thread_getcontext(struct thread *td, ucontext_t *uc)
 #ifdef __i386__
 	get_mcontext(td, &uc->uc_mcontext);
 #endif
-	uc->uc_sigmask = td->td_proc->p_sigmask;
+	uc->uc_sigmask = td->td_sigmask;
 }
 
 /*
@@ -769,7 +771,7 @@ thread_setcontext(struct thread *td, ucontext_t *uc)
 	if (ret == 0) {
 		SIG_CANTMASK(uc->uc_sigmask);
 		PROC_LOCK(td->td_proc);
-		td->td_proc->p_sigmask = uc->uc_sigmask;
+		td->td_sigmask = uc->uc_sigmask;
 		PROC_UNLOCK(td->td_proc);
 	}
 	return (ret);
@@ -1247,6 +1249,7 @@ thread_exit(void)
 	} else {
 		PROC_UNLOCK(p);
 	}
+	/* XXX Shouldn't cpu_throw() here. */
 	cpu_throw();
 	/* NOTREACHED */
 }
@@ -1428,8 +1431,10 @@ thread_schedule_upcall(struct thread *td, struct kse_upcall *ku)
 	ku->ku_owner   = td2;
 	td2->td_upcall = ku;
 	td2->td_flags  = TDF_UPCALLING;
+#if 0	/* XXX This shouldn't be necessary */
 	if (td->td_proc->p_sflag & PS_NEEDSIGCHK)
 		td2->td_flags |= TDF_ASTPENDING;
+#endif
 	td2->td_kse    = NULL;
 	td2->td_state  = TDS_CAN_RUN;
 	td2->td_inhibitors = 0;
@@ -1593,6 +1598,7 @@ thread_userret(struct thread *td, struct trapframe *frame)
 	p = td->td_proc;
 	kg = td->td_ksegrp;
 
+	
 	/* Nothing to do with non-threaded group/process */
 	if (td->td_ksegrp->kg_numupcalls == 0)
 		return (0);
@@ -1621,12 +1627,12 @@ thread_userret(struct thread *td, struct trapframe *frame)
 	if (TD_CAN_UNBIND(td)) {
 		mtx_lock_spin(&sched_lock);
 		td->td_flags &= ~TDF_CAN_UNBIND;
-		mtx_unlock_spin(&sched_lock);
 		ku = td->td_upcall;
-		if ((p->p_sflag & PS_NEEDSIGCHK) == 0 &&
+		if ((td->td_flags & TDF_NEEDSIGCHK) == 0 &&
 		    (kg->kg_completed == NULL) &&
 		    (ku->ku_flags & KUF_DOUPCALL) == 0 &&
 		    (kg->kg_upquantum && ticks >= kg->kg_nextupcall)) {
+			mtx_unlock_spin(&sched_lock);
 			thread_update_usr_ticks(td, 0);
 			nanotime(&ts);
 			error = copyout(&ts,
@@ -1637,6 +1643,7 @@ thread_userret(struct thread *td, struct trapframe *frame)
 				goto out;
 			return (0);
 		}
+		mtx_unlock_spin(&sched_lock);
 		error = thread_export_context(td);
 		if (error) {
 			/*
diff --git a/sys/kern/subr_smp.c b/sys/kern/subr_smp.c
index 908d587..f65987f 100644
--- a/sys/kern/subr_smp.c
+++ b/sys/kern/subr_smp.c
@@ -123,8 +123,8 @@ forward_signal(struct thread *td)
 	int id;
 
 	/*
-	 * signotify() has already set TDF_ASTPENDING and PS_NEEDSIGCHECK on
-	 * this process, so all we need to do is poke it if it is currently
+	 * signotify() has already set TDF_ASTPENDING and TDF_NEEDSIGCHECK on
+	 * this thread, so all we need to do is poke it if it is currently
 	 * executing so that it executes ast().
 	 */
 	mtx_assert(&sched_lock, MA_OWNED);
diff --git a/sys/kern/subr_trap.c b/sys/kern/subr_trap.c
index 7fe4883..9cc7dbe 100644
--- a/sys/kern/subr_trap.c
+++ b/sys/kern/subr_trap.c
@@ -81,7 +81,7 @@ userret(td, frame, oticks)
 	mtx_lock(&Giant);
 	PROC_LOCK(p);
 	mtx_lock_spin(&sched_lock);
-	if (SIGPENDING(p) && ((p->p_sflag & PS_NEEDSIGCHK) == 0 ||
+	if (SIGPENDING(td) && ((td->td_flags & TDF_NEEDSIGCHK) == 0 ||
 	    (td->td_flags & TDF_ASTPENDING) == 0))
 		printf("failed to set signal flags properly for ast()\n");
 	mtx_unlock_spin(&sched_lock);
@@ -174,11 +174,12 @@ ast(struct trapframe *framep)
 	sticks = td->td_sticks;
 	flags = td->td_flags;
 	sflag = p->p_sflag;
-	p->p_sflag &= ~(PS_ALRMPEND | PS_NEEDSIGCHK | PS_PROFPEND | PS_XCPU);
+	p->p_sflag &= ~(PS_ALRMPEND | PS_PROFPEND | PS_XCPU);
 #ifdef MAC
 	p->p_sflag &= ~PS_MACPEND;
 #endif
-	td->td_flags &= ~(TDF_ASTPENDING | TDF_NEEDRESCHED | TDF_OWEUPC);
+	td->td_flags &= ~(TDF_ASTPENDING | TDF_NEEDSIGCHK |
+	    TDF_NEEDRESCHED | TDF_OWEUPC);
 	cnt.v_soft++;
 	prticks = 0;
 	if (flags & TDF_OWEUPC && sflag & PS_PROFIL) {
@@ -243,7 +244,7 @@ ast(struct trapframe *framep)
 		mi_switch();
 		mtx_unlock_spin(&sched_lock);
 	}
-	if (sflag & PS_NEEDSIGCHK) {
+	if (flags & TDF_NEEDSIGCHK) {
 		int sigs;
 
 		sigs = 0;
diff --git a/sys/kern/tty.c b/sys/kern/tty.c
index c0ad4a2..d9d68c6 100644
--- a/sys/kern/tty.c
+++ b/sys/kern/tty.c
@@ -777,7 +777,7 @@ ttioctl(struct tty *tp, u_long cmd, void *data, int flag)
 		PROC_LOCK(p);
 		while (isbackground(p, tp) && !(p->p_flag & P_PPWAIT) &&
 		    !SIGISMEMBER(p->p_sigignore, SIGTTOU) &&
-		    !SIGISMEMBER(p->p_sigmask, SIGTTOU)) {
+		    !SIGISMEMBER(td->td_sigmask, SIGTTOU)) {
 			pgrp = p->p_pgrp;
 			PROC_UNLOCK(p);
 			if (pgrp->pg_jobc == 0) {
@@ -1571,13 +1571,16 @@ ttread(struct tty *tp, struct uio *uio, int flag)
 	int c;
 	tcflag_t lflag;
 	cc_t *cc = tp->t_cc;
-	struct proc *p = curproc;
+	struct thread *td;
+	struct proc *p;
 	int s, first, error = 0;
 	int has_stime = 0, last_cc = 0;
 	long slp = 0;		/* XXX this should be renamed `timo'. */
 	struct timeval stime;
 	struct pgrp *pg;
 
+	td = curthread;
+	p = td->td_proc;
 loop:
 	s = spltty();
 	lflag = tp->t_lflag;
@@ -1599,7 +1602,7 @@ loop:
 		sx_slock(&proctree_lock);
 		PROC_LOCK(p);
 		if (SIGISMEMBER(p->p_sigignore, SIGTTIN) ||
-		    SIGISMEMBER(p->p_sigmask, SIGTTIN) ||
+		    SIGISMEMBER(td->td_sigmask, SIGTTIN) ||
 		    (p->p_flag & P_PPWAIT) || p->p_pgrp->pg_jobc == 0) {
 			PROC_UNLOCK(p);
 			sx_sunlock(&proctree_lock);
@@ -1847,15 +1850,16 @@ ttycheckoutq(struct tty *tp, int wait)
 {
 	int hiwat, s;
 	sigset_t oldmask;
-	struct proc *p = curproc;
+	struct thread *td;
 
+	td = curthread;
 	hiwat = tp->t_ohiwat;
 	SIGEMPTYSET(oldmask);
 	s = spltty();
 	if (wait) {
-		PROC_LOCK(p);
-		oldmask = p->p_siglist;
-		PROC_UNLOCK(p);
+		PROC_LOCK(td->td_proc);
+		oldmask = td->td_siglist;
+		PROC_UNLOCK(td->td_proc);
 	}
 	if (tp->t_outq.c_cc > hiwat + OBUFSIZ + 100)
 		while (tp->t_outq.c_cc > hiwat) {
@@ -1866,13 +1870,13 @@ ttycheckoutq(struct tty *tp, int wait)
 				splx(s);
 				return (0);
 			}
-			PROC_LOCK(p);
-			if (!SIGSETEQ(p->p_siglist, oldmask)) {
-				PROC_UNLOCK(p);
+			PROC_LOCK(td->td_proc);
+			if (!SIGSETEQ(td->td_siglist, oldmask)) {
+				PROC_UNLOCK(td->td_proc);
 				splx(s);
 				return (0);
 			}
-			PROC_UNLOCK(p);
+			PROC_UNLOCK(td->td_proc);
 			SET(tp->t_state, TS_SO_OLOWAT);
 			tsleep(TSA_OLOWAT(tp), PZERO - 1, "ttoutq", hz);
 		}
@@ -1888,6 +1892,7 @@ ttwrite(struct tty *tp, struct uio *uio, int flag)
 {
 	char *cp = NULL;
 	int cc, ce;
+	struct thread *td;
 	struct proc *p;
 	int i, hiwat, cnt, error, s;
 	char obuf[OBUFSIZ];
@@ -1896,6 +1901,8 @@ ttwrite(struct tty *tp, struct uio *uio, int flag)
 	cnt = uio->uio_resid;
 	error = 0;
 	cc = 0;
+	td = curthread;
+	p = td->td_proc;
 loop:
 	s = spltty();
 	if (ISSET(tp->t_state, TS_ZOMBIE)) {
@@ -1921,13 +1928,12 @@ loop:
 	/*
 	 * Hang the process if it's in the background.
 	 */
-	p = curproc;
 	sx_slock(&proctree_lock);
 	PROC_LOCK(p);
 	if (isbackground(p, tp) &&
 	    ISSET(tp->t_lflag, TOSTOP) && !(p->p_flag & P_PPWAIT) &&
 	    !SIGISMEMBER(p->p_sigignore, SIGTTOU) &&
-	    !SIGISMEMBER(p->p_sigmask, SIGTTOU)) {
+	    !SIGISMEMBER(td->td_sigmask, SIGTTOU)) {
 		if (p->p_pgrp->pg_jobc == 0) {
 			PROC_UNLOCK(p);
 			sx_sunlock(&proctree_lock);
diff --git a/sys/kern/tty_pty.c b/sys/kern/tty_pty.c
index da408fc..b104e6b 100644
--- a/sys/kern/tty_pty.c
+++ b/sys/kern/tty_pty.c
@@ -236,7 +236,7 @@ again:
 			sx_slock(&proctree_lock);
 			PROC_LOCK(p);
 			if (SIGISMEMBER(p->p_sigignore, SIGTTIN) ||
-			    SIGISMEMBER(p->p_sigmask, SIGTTIN) ||
+			    SIGISMEMBER(td->td_sigmask, SIGTTIN) ||
 			    p->p_pgrp->pg_jobc == 0 || p->p_flag & P_PPWAIT) {
 				PROC_UNLOCK(p);
 				sx_sunlock(&proctree_lock);
diff --git a/sys/netncp/ncp_ncp.c b/sys/netncp/ncp_ncp.c
index c1c77b0..0541793 100644
--- a/sys/netncp/ncp_ncp.c
+++ b/sys/netncp/ncp_ncp.c
@@ -86,9 +86,10 @@ ncp_chkintr(struct ncp_conn *conn, struct thread *td)
 	p = td->td_proc;
 	PROC_LOCK(p);
 	tmpset = p->p_siglist;
-	SIGSETNAND(tmpset, p->p_sigmask);
+	SIGSETOR(tmpset, td->td_siglist);
+	SIGSETNAND(tmpset, td->td_sigmask);
 	SIGSETNAND(tmpset, p->p_sigignore);
-	if (SIGNOTEMPTY(p->p_siglist) && NCP_SIGMASK(tmpset)) {
+	if (SIGNOTEMPTY(td->td_siglist) && NCP_SIGMASK(tmpset)) {
 		PROC_UNLOCK(p);
                 return EINTR;
 	}
diff --git a/sys/netsmb/smb_iod.c b/sys/netsmb/smb_iod.c
index 5ae5f14..bc8e20b 100644
--- a/sys/netsmb/smb_iod.c
+++ b/sys/netsmb/smb_iod.c
@@ -356,7 +356,7 @@ smb_iod_recvall(struct smbiod *iod)
 	 */
 	SMB_IOD_RQLOCK(iod);
 	TAILQ_FOREACH(rqp, &iod->iod_rqlist, sr_link) {
-		if (smb_proc_intr(rqp->sr_cred->scr_td->td_proc)) {
+		if (smb_td_intr(rqp->sr_cred->scr_td)) {
 			smb_iod_rqprocessed(rqp, EINTR);
 		}
 	}
diff --git a/sys/netsmb/smb_rq.c b/sys/netsmb/smb_rq.c
index 5e0c7a8..456672d 100644
--- a/sys/netsmb/smb_rq.c
+++ b/sys/netsmb/smb_rq.c
@@ -184,7 +184,7 @@ smb_rq_enqueue(struct smb_rq *rqp)
 		if (ssp->ss_flags & SMBS_RECONNECTING) {
 			msleep(&ssp->ss_vcgenid, SMBS_ST_LOCKPTR(ssp),
 			    PWAIT | PDROP, "90trcn", hz);
-			if (smb_proc_intr(rqp->sr_cred->scr_td->td_proc))
+			if (smb_td_intr(rqp->sr_cred->scr_td))
 				return EINTR;
 			continue;
 		}
@@ -248,11 +248,9 @@ smb_rq_bend(struct smb_rq *rqp)
 int
 smb_rq_intr(struct smb_rq *rqp)
 {
-	struct proc *p = rqp->sr_cred->scr_td->td_proc;
-
 	if (rqp->sr_flags & SMBR_INTR)
 		return EINTR;
-	return smb_proc_intr(p);
+	return smb_td_intr(rqp->sr_cred->scr_td);
 }
 
 int
diff --git a/sys/netsmb/smb_subr.c b/sys/netsmb/smb_subr.c
index 55c4c26..0e03560 100644
--- a/sys/netsmb/smb_subr.c
+++ b/sys/netsmb/smb_subr.c
@@ -69,17 +69,21 @@ smb_makescred(struct smb_cred *scred, struct thread *td, struct ucred *cred)
 }
 
 int
-smb_proc_intr(struct proc *p)
+smb_td_intr(struct thread *td)
 {
+	struct proc *p;
 	sigset_t tmpset;
 
-	if (p == NULL)
+	if (td == NULL)
 		return 0;
+
+	p = td->td_proc;
 	PROC_LOCK(p);
 	tmpset = p->p_siglist;
-	SIGSETNAND(tmpset, p->p_sigmask);
+	SIGSETOR(tmpset, td->td_siglist);
+	SIGSETNAND(tmpset, td->td_sigmask);
 	SIGSETNAND(tmpset, p->p_sigignore);
-	if (SIGNOTEMPTY(p->p_siglist) && SMB_SIGMASK(tmpset)) {
+	if (SIGNOTEMPTY(td->td_siglist) && SMB_SIGMASK(tmpset)) {
 		PROC_UNLOCK(p);
                 return EINTR;
 	}
diff --git a/sys/netsmb/smb_subr.h b/sys/netsmb/smb_subr.h
index 537d220..684f6bb 100644
--- a/sys/netsmb/smb_subr.h
+++ b/sys/netsmb/smb_subr.h
@@ -140,7 +140,7 @@ struct smb_vc;
 struct smb_rq;
 
 void smb_makescred(struct smb_cred *scred, struct thread *td, struct ucred *cred);
-int  smb_proc_intr(struct proc *);
+int  smb_td_intr(struct thread *);
 char *smb_strdup(const char *s);
 void *smb_memdup(const void *umem, int len);
 char *smb_strdupin(char *s, int maxlen);
diff --git a/sys/nfsclient/nfs_socket.c b/sys/nfsclient/nfs_socket.c
index 9f0a3c4..3949b74 100644
--- a/sys/nfsclient/nfs_socket.c
+++ b/sys/nfsclient/nfs_socket.c
@@ -1238,7 +1238,7 @@ nfs_sigintr(struct nfsmount *nmp, struct nfsreq *rep, struct thread *td)
 	p = td->td_proc;
 	PROC_LOCK(p);
 	tmpset = p->p_siglist;
-	SIGSETNAND(tmpset, p->p_sigmask);
+	SIGSETNAND(tmpset, td->td_sigmask);
 	SIGSETNAND(tmpset, p->p_sigignore);
 	if (SIGNOTEMPTY(p->p_siglist) && NFSINT_SIGMASK(tmpset)) {
 		PROC_UNLOCK(p);
diff --git a/sys/pc98/i386/machdep.c b/sys/pc98/i386/machdep.c
index 6ccdffe..2b2b979 100644
--- a/sys/pc98/i386/machdep.c
+++ b/sys/pc98/i386/machdep.c
@@ -771,9 +771,9 @@ osigreturn(td, uap)
 	else
 		p->p_sigstk.ss_flags &= ~SS_ONSTACK;
 #endif
-	SIGSETOLD(p->p_sigmask, scp->sc_mask);
-	SIG_CANTMASK(p->p_sigmask);
-	signotify(p);
+	SIGSETOLD(td->td_sigmask, scp->sc_mask);
+	SIG_CANTMASK(td->td_sigmask);
+	signotify(td);
 	PROC_UNLOCK(p);
 	return (EJUSTRETURN);
 }
@@ -879,9 +879,9 @@ freebsd4_sigreturn(td, uap)
 		p->p_sigstk.ss_flags &= ~SS_ONSTACK;
 #endif
 
-	p->p_sigmask = ucp->uc_sigmask;
-	SIG_CANTMASK(p->p_sigmask);
-	signotify(p);
+	td->td_sigmask = ucp->uc_sigmask;
+	SIG_CANTMASK(td->td_sigmask);
+	signotify(td);
 	PROC_UNLOCK(p);
 	return (EJUSTRETURN);
 }
@@ -989,9 +989,9 @@ sigreturn(td, uap)
 		p->p_sigstk.ss_flags &= ~SS_ONSTACK;
 #endif
 
-	p->p_sigmask = ucp->uc_sigmask;
-	SIG_CANTMASK(p->p_sigmask);
-	signotify(p);
+	td->td_sigmask = ucp->uc_sigmask;
+	SIG_CANTMASK(td->td_sigmask);
+	signotify(td);
 	PROC_UNLOCK(p);
 	return (EJUSTRETURN);
 }
diff --git a/sys/pc98/pc98/machdep.c b/sys/pc98/pc98/machdep.c
index 6ccdffe..2b2b979 100644
--- a/sys/pc98/pc98/machdep.c
+++ b/sys/pc98/pc98/machdep.c
@@ -771,9 +771,9 @@ osigreturn(td, uap)
 	else
 		p->p_sigstk.ss_flags &= ~SS_ONSTACK;
 #endif
-	SIGSETOLD(p->p_sigmask, scp->sc_mask);
-	SIG_CANTMASK(p->p_sigmask);
-	signotify(p);
+	SIGSETOLD(td->td_sigmask, scp->sc_mask);
+	SIG_CANTMASK(td->td_sigmask);
+	signotify(td);
 	PROC_UNLOCK(p);
 	return (EJUSTRETURN);
 }
@@ -879,9 +879,9 @@ freebsd4_sigreturn(td, uap)
 		p->p_sigstk.ss_flags &= ~SS_ONSTACK;
 #endif
 
-	p->p_sigmask = ucp->uc_sigmask;
-	SIG_CANTMASK(p->p_sigmask);
-	signotify(p);
+	td->td_sigmask = ucp->uc_sigmask;
+	SIG_CANTMASK(td->td_sigmask);
+	signotify(td);
 	PROC_UNLOCK(p);
 	return (EJUSTRETURN);
 }
@@ -989,9 +989,9 @@ sigreturn(td, uap)
 		p->p_sigstk.ss_flags &= ~SS_ONSTACK;
 #endif
 
-	p->p_sigmask = ucp->uc_sigmask;
-	SIG_CANTMASK(p->p_sigmask);
-	signotify(p);
+	td->td_sigmask = ucp->uc_sigmask;
+	SIG_CANTMASK(td->td_sigmask);
+	signotify(td);
 	PROC_UNLOCK(p);
 	return (EJUSTRETURN);
 }
diff --git a/sys/powerpc/aim/machdep.c b/sys/powerpc/aim/machdep.c
index 92cc11e..54661aa 100644
--- a/sys/powerpc/aim/machdep.c
+++ b/sys/powerpc/aim/machdep.c
@@ -538,9 +538,9 @@ sigreturn(struct thread *td, struct sigreturn_args *uap)
 
 	p = td->td_proc;
 	PROC_LOCK(p);
-	p->p_sigmask = uc.uc_sigmask;
-	SIG_CANTMASK(p->p_sigmask);
-	signotify(p);
+	td->td_sigmask = uc.uc_sigmask;
+	SIG_CANTMASK(td->td_sigmask);
+	signotify(td);
 	PROC_UNLOCK(p);
 
 	/*
diff --git a/sys/powerpc/powerpc/machdep.c b/sys/powerpc/powerpc/machdep.c
index 92cc11e..54661aa 100644
--- a/sys/powerpc/powerpc/machdep.c
+++ b/sys/powerpc/powerpc/machdep.c
@@ -538,9 +538,9 @@ sigreturn(struct thread *td, struct sigreturn_args *uap)
 
 	p = td->td_proc;
 	PROC_LOCK(p);
-	p->p_sigmask = uc.uc_sigmask;
-	SIG_CANTMASK(p->p_sigmask);
-	signotify(p);
+	td->td_sigmask = uc.uc_sigmask;
+	SIG_CANTMASK(td->td_sigmask);
+	signotify(td);
 	PROC_UNLOCK(p);
 
 	/*
diff --git a/sys/sparc64/sparc64/machdep.c b/sys/sparc64/sparc64/machdep.c
index ba8f162..fa2ba40 100644
--- a/sys/sparc64/sparc64/machdep.c
+++ b/sys/sparc64/sparc64/machdep.c
@@ -492,9 +492,9 @@ sigreturn(struct thread *td, struct sigreturn_args *uap)
 	bcopy(mc, tf, sizeof(*tf));
 
 	PROC_LOCK(p);
-	p->p_sigmask = uc.uc_sigmask;
-	SIG_CANTMASK(p->p_sigmask);
-	signotify(p);
+	td->td_sigmask = uc.uc_sigmask;
+	SIG_CANTMASK(td->td_sigmask);
+	signotify(td);
 	PROC_UNLOCK(p);
 
 	CTR4(KTR_SIG, "sigreturn: return td=%p pc=%#lx sp=%#lx tstate=%#lx",
diff --git a/sys/sys/signalvar.h b/sys/sys/signalvar.h
index 9ee4445..0baa57e 100644
--- a/sys/sys/signalvar.h
+++ b/sys/sys/signalvar.h
@@ -191,10 +191,10 @@ __sigseteq(sigset_t *set1, sigset_t *set2)
 #ifdef _KERNEL
 
 /* Return nonzero if process p has an unmasked pending signal. */
-#define	SIGPENDING(p)							\
-	(!SIGISEMPTY((p)->p_siglist) &&					\
-	    (!sigsetmasked(&(p)->p_siglist, &(p)->p_sigmask) ||		\
-	    (p)->p_flag & P_TRACED))
+#define	SIGPENDING(td)							\
+	(!SIGISEMPTY((td)->td_siglist) &&				\
+	    (!sigsetmasked(&(td)->td_siglist, &(td)->td_sigmask) ||	\
+	    (td)->td_proc->p_flag & P_TRACED))
 
 /*
  * Return the value of the pseudo-expression ((*set & ~*mask) != 0).  This
@@ -244,10 +244,14 @@ void	pgsigio(struct sigio **, int signum, int checkctty);
 void	pgsignal(struct pgrp *pgrp, int sig, int checkctty);
 void	postsig(int sig);
 void	psignal(struct proc *p, int sig);
+void	tdsignal(struct thread *td, int sig);
 void	sigexit(struct thread *td, int signum) __dead2;
 void	siginit(struct proc *p);
-void	signotify(struct proc *p);
+void	signotify(struct thread *td);
 void	trapsignal(struct thread *td, int sig, u_long code);
+int	do_sigprocmask(struct thread *td, int how,
+			sigset_t *set, sigset_t *oset, int old);
+int	sig_ffs(sigset_t *set);
 
 /*
  * Machine-dependent functions: