Protect thread errno from being changed while operating

on behalf of the KSE.

Add a kse_reinit function to reinitialize a reused KSE.

Submitted by:	davidxu

6 files changed, 76 insertions, 2 deletions

diff --git a/lib/libkse/sys/thr_error.c b/lib/libkse/sys/thr_error.c
index a4a8507..6f19f93 100644
--- a/lib/libkse/sys/thr_error.c
+++ b/lib/libkse/sys/thr_error.c
@@ -36,14 +36,18 @@
 #include <pthread.h>
 #include "libc_private.h"
 #include "thr_private.h"
+
 extern	int	errno;
 
-int * __error()
+int *
+__error(void)
 {
 	struct pthread *curthread;
 
 	if (__isthreaded == 0)
 		return (&errno);
+	else if (_kse_in_critical())
+		return &(_get_curkse()->k_error);
 	else {
 		curthread = _get_curthread();
 		if ((curthread == NULL) || (curthread == _thr_initial))
diff --git a/lib/libkse/thread/thr_kern.c b/lib/libkse/thread/thr_kern.c
index 2da990e..63283f7 100644
--- a/lib/libkse/thread/thr_kern.c
+++ b/lib/libkse/thread/thr_kern.c
@@ -128,6 +128,7 @@ static void	kse_check_completed(struct kse *kse);
 static void	kse_check_waitq(struct kse *kse);
 static void	kse_check_signals(struct kse *kse);
 static void	kse_fini(struct kse *curkse);
+static void	kse_reinit(struct kse *kse);
 static void	kse_sched_multi(struct kse *curkse);
 #ifdef NOT_YET
 static void	kse_sched_single(struct kse *curkse);
@@ -270,6 +271,10 @@ _kse_single_thread(struct pthread *curthread)
 	/* Free the to-be-gc'd threads. */
 	while ((thread = TAILQ_FIRST(&_thread_gc_list)) != NULL) {
 		TAILQ_REMOVE(&_thread_gc_list, thread, gcle);
+		for (i = 0; i < MAX_THR_LOCKLEVEL; i++) {
+			_lockuser_destroy(&thread->lockusers[i]);
+		}
+		_lock_destroy(&thread->lock);
 		free(thread);
 	}
 	TAILQ_INIT(&gc_ksegq);
@@ -508,6 +513,12 @@ _kse_critical_leave(kse_critical_t crit)
 		THR_YIELD_CHECK(curthread);
 }
 
+int
+_kse_in_critical(void)
+{
+	return (_ksd_get_tmbx() == NULL);
+}
+
 void
 _thr_critical_enter(struct pthread *thread)
 {
@@ -1777,6 +1788,8 @@ _kse_alloc(struct pthread *curthread)
 		}
 		KSE_LOCK_RELEASE(curthread->kse, &kse_lock);
 		_kse_critical_leave(crit);
+		if (kse != NULL)
+			kse_reinit(kse);
 	}
 	if ((kse == NULL) &&
 	    ((kse = (struct kse *)malloc(sizeof(*kse))) != NULL)) {
@@ -1852,6 +1865,24 @@ _kse_alloc(struct pthread *curthread)
 	return (kse);
 }
 
+static void
+kse_reinit(struct kse *kse)
+{
+	bzero(&kse->k_mbx, sizeof(struct kse_mailbox));
+	kse->k_curthread = 0;
+	kse->k_kseg = 0;
+	kse->k_schedq = 0;
+	kse->k_locklevel = 0;
+	sigemptyset(&kse->k_sigmask);
+	bzero(&kse->k_sigq, sizeof(kse->k_sigq));
+	kse->k_check_sigq = 0;
+	kse->k_flags = KF_INITIALIZED;
+	kse->k_waiting = 0;
+	kse->k_error = 0;
+	kse->k_cpu = 0;
+	kse->k_done = 0;
+}
+
 void
 kse_free_unlocked(struct kse *kse)
 {
diff --git a/lib/libkse/thread/thr_private.h b/lib/libkse/thread/thr_private.h
index a554796..fc2e4ee 100644
--- a/lib/libkse/thread/thr_private.h
+++ b/lib/libkse/thread/thr_private.h
@@ -197,6 +197,7 @@ struct kse {
 #define	KF_STARTED			0x0001	/* kernel kse created */
 #define	KF_INITIALIZED			0x0002	/* initialized on 1st upcall */
 	int			k_waiting;
+	int			k_error;	/* syscall errno in critical */
 	int			k_cpu;		/* CPU ID when bound */
 	int			k_done;		/* this KSE is done */
 };
@@ -1014,6 +1015,7 @@ void	_set_curkse(struct kse *);
 struct kse *_kse_alloc(struct pthread *);
 kse_critical_t _kse_critical_enter(void);
 void	_kse_critical_leave(kse_critical_t);
+int	_kse_in_critical(void);
 void	_kse_free(struct pthread *, struct kse *);
 void	_kse_init();
 struct kse_group *_kseg_alloc(struct pthread *);
diff --git a/lib/libpthread/sys/thr_error.c b/lib/libpthread/sys/thr_error.c
index a4a8507..6f19f93 100644
--- a/lib/libpthread/sys/thr_error.c
+++ b/lib/libpthread/sys/thr_error.c
@@ -36,14 +36,18 @@
 #include <pthread.h>
 #include "libc_private.h"
 #include "thr_private.h"
+
 extern	int	errno;
 
-int * __error()
+int *
+__error(void)
 {
 	struct pthread *curthread;
 
 	if (__isthreaded == 0)
 		return (&errno);
+	else if (_kse_in_critical())
+		return &(_get_curkse()->k_error);
 	else {
 		curthread = _get_curthread();
 		if ((curthread == NULL) || (curthread == _thr_initial))
diff --git a/lib/libpthread/thread/thr_kern.c b/lib/libpthread/thread/thr_kern.c
index 2da990e..63283f7 100644
--- a/lib/libpthread/thread/thr_kern.c
+++ b/lib/libpthread/thread/thr_kern.c
@@ -128,6 +128,7 @@ static void	kse_check_completed(struct kse *kse);
 static void	kse_check_waitq(struct kse *kse);
 static void	kse_check_signals(struct kse *kse);
 static void	kse_fini(struct kse *curkse);
+static void	kse_reinit(struct kse *kse);
 static void	kse_sched_multi(struct kse *curkse);
 #ifdef NOT_YET
 static void	kse_sched_single(struct kse *curkse);
@@ -270,6 +271,10 @@ _kse_single_thread(struct pthread *curthread)
 	/* Free the to-be-gc'd threads. */
 	while ((thread = TAILQ_FIRST(&_thread_gc_list)) != NULL) {
 		TAILQ_REMOVE(&_thread_gc_list, thread, gcle);
+		for (i = 0; i < MAX_THR_LOCKLEVEL; i++) {
+			_lockuser_destroy(&thread->lockusers[i]);
+		}
+		_lock_destroy(&thread->lock);
 		free(thread);
 	}
 	TAILQ_INIT(&gc_ksegq);
@@ -508,6 +513,12 @@ _kse_critical_leave(kse_critical_t crit)
 		THR_YIELD_CHECK(curthread);
 }
 
+int
+_kse_in_critical(void)
+{
+	return (_ksd_get_tmbx() == NULL);
+}
+
 void
 _thr_critical_enter(struct pthread *thread)
 {
@@ -1777,6 +1788,8 @@ _kse_alloc(struct pthread *curthread)
 		}
 		KSE_LOCK_RELEASE(curthread->kse, &kse_lock);
 		_kse_critical_leave(crit);
+		if (kse != NULL)
+			kse_reinit(kse);
 	}
 	if ((kse == NULL) &&
 	    ((kse = (struct kse *)malloc(sizeof(*kse))) != NULL)) {
@@ -1852,6 +1865,24 @@ _kse_alloc(struct pthread *curthread)
 	return (kse);
 }
 
+static void
+kse_reinit(struct kse *kse)
+{
+	bzero(&kse->k_mbx, sizeof(struct kse_mailbox));
+	kse->k_curthread = 0;
+	kse->k_kseg = 0;
+	kse->k_schedq = 0;
+	kse->k_locklevel = 0;
+	sigemptyset(&kse->k_sigmask);
+	bzero(&kse->k_sigq, sizeof(kse->k_sigq));
+	kse->k_check_sigq = 0;
+	kse->k_flags = KF_INITIALIZED;
+	kse->k_waiting = 0;
+	kse->k_error = 0;
+	kse->k_cpu = 0;
+	kse->k_done = 0;
+}
+
 void
 kse_free_unlocked(struct kse *kse)
 {
diff --git a/lib/libpthread/thread/thr_private.h b/lib/libpthread/thread/thr_private.h
index a554796..fc2e4ee 100644
--- a/lib/libpthread/thread/thr_private.h
+++ b/lib/libpthread/thread/thr_private.h
@@ -197,6 +197,7 @@ struct kse {
 #define	KF_STARTED			0x0001	/* kernel kse created */
 #define	KF_INITIALIZED			0x0002	/* initialized on 1st upcall */
 	int			k_waiting;
+	int			k_error;	/* syscall errno in critical */
 	int			k_cpu;		/* CPU ID when bound */
 	int			k_done;		/* this KSE is done */
 };
@@ -1014,6 +1015,7 @@ void	_set_curkse(struct kse *);
 struct kse *_kse_alloc(struct pthread *);
 kse_critical_t _kse_critical_enter(void);
 void	_kse_critical_leave(kse_critical_t);
+int	_kse_in_critical(void);
 void	_kse_free(struct pthread *, struct kse *);
 void	_kse_init();
 struct kse_group *_kseg_alloc(struct pthread *);