Bug #2724: fork from other than the main thread causes wrong pthread
condition on NetBSD
http://redmine.ruby-lang.org/issues/show/2724
e$B5/I<<Te(B: Yui NARUSE
e$B%9%F!<%?%9e(B: Third Party’s Issue, e$BM%@hEYe(B: Normal
e$B%+%F%4%je(B: core
ruby -v: ruby 1.9.2dev (2010-02-07 trunk 26615) [i386-netbsdelf5.0.1]
NetBSD 5.0.[01] e$B$K$*$$$F!"e(Bmain thread e$B0J30$Ne(B pthread
e$B$+$ie(B fork e$B$9$k$H!“e(B
pthread e$B$H%+!<%M%k%9%l%C%Ie(B (lwp)
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e$B8e=R$N%Q%C%A$,$“$^$j$K%”%l$J$N$G$3$NLdBj$Oe(B Third Party’s Issue
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Ruby e$BB&$G$O=$@5$rF~$l$J$$;v$H$7$^$9$,!”>pJs$N6&M-$H5-O?$N$?$a$Ke(B
e$B$3$3$K%A%1%C%H$r@Z$C$F$*$-$^$9!#e(B
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Index: thread_pthread.c
— thread_pthread.c (revision 26615)
+++ thread_pthread.c (working copy)
@@ -17,6 +17,93 @@
#include <sys/resource.h>
#endif
+#if defined(NetBSD_Version) && NetBSD_Version >= 500000000
+/* Hack for NetBSD 5.0.x’s broken pthread->pt_lid /
+/ Copied from /src/lib/libpthread/pthread_int.h /
+#define BROKEN_PTHREAD_T_PT_LID
+#include <lwp.h>
+#include <pthread_queue.h>
+#include <sys/tree.h>
+
+#define PTHREAD_KEYS_MAX 256
+#define PTHREAD__UNPARK_MAX 32
+
+/
-
- The size of this structure needs to be no larger than struct
-
- __pthread_cleanup_store, defined in pthread.h.
- */
+struct pt_clean_t { -
PTQ_ENTRY(pt_clean_t) ptc_next; -
void (*ptc_cleanup)(void *); -
void *ptc_arg;
+};
+
+struct pthread_lock_ops {
-
void (*plo_init)(__cpu_simple_lock_t *); -
int (*plo_try)(__cpu_simple_lock_t *); -
void (*plo_unlock)(__cpu_simple_lock_t *); -
void (*plo_lock)(__cpu_simple_lock_t *);
+};
+
+struct __pthread_st {
-
pthread_t pt_self; /* Must be first. */ -
unsigned int pt_magic; /* Magic number */ -
int pt_state; /* running, blocked, etc. */ -
pthread_mutex_t pt_lock; /* lock on state */ -
int pt_flags; /* see PT_FLAG_* below */ -
int pt_cancel; /* Deferred cancellation */ -
int pt_errno; /* Thread-specific errno. */ -
stack_t pt_stack; /* Our stack */ -
void *pt_exitval; /* Read by pthread_join() */ -
char *pt_name; /* Thread's name, set by the
app. */
-
int pt_willpark; /* About to park */ -
lwpid_t pt_unpark; /* Unpark this when parking */ -
struct pthread_lock_ops pt_lockops;/* Cached to avoid PIC
overhead */
-
pthread_mutex_t *pt_droplock; /* Drop this lock if cancelled
*/
-
pthread_cond_t pt_joiners; /* Threads waiting to join. */ -
/* Threads to defer waking, usually until
pthread_mutex_unlock(). */
-
lwpid_t pt_waiters[PTHREAD__UNPARK_MAX]; -
size_t pt_nwaiters; -
/* Stack of cancellation cleanup handlers and their arguments */ -
PTQ_HEAD(, pt_clean_t) pt_cleanup_stack; -
/* LWP ID and entry on the list of all threads. */ -
lwpid_t pt_lid; -
RB_ENTRY(__pthread_st) pt_alltree; -
PTQ_ENTRY(__pthread_st) pt_allq; -
PTQ_ENTRY(__pthread_st) pt_deadq; -
/* -
* General synchronization data. We try to align, as threads -
* on other CPUs will access this data frequently. -
*/ -
int pt_dummy1 __aligned(128); -
struct lwpctl *pt_lwpctl; /* Kernel/user comms area */ -
volatile int pt_blocking; /* Blocking in userspace */ -
volatile int pt_rwlocked; /* Handed rwlock successfully */ -
volatile int pt_signalled; /* Received
pthread_cond_signal() */
-
volatile int pt_mutexwait; /* Waiting to acquire mutex */ -
void * volatile pt_mutexnext; /* Next thread in chain */ -
void * volatile pt_sleepobj; /* Object slept on */ -
PTQ_ENTRY(__pthread_st) pt_sleep; -
void (*pt_early)(void *); -
int pt_dummy2 __aligned(128); -
/* Thread-specific data. Large so it sits close to the end. */ -
int pt_havespecific; -
void *pt_specific[PTHREAD_KEYS_MAX]; -
/* -
* Context for thread creation. At the end as it's cached -
* and then only ever passed to _lwp_create(). -
*/ -
ucontext_t pt_uc;
+};
+#endif /* NetBSD */
+
+
static void native_mutex_lock(pthread_mutex_t *lock);
static void native_mutex_unlock(pthread_mutex_t *lock);
static int native_mutex_trylock(pthread_mutex_t *lock);
@@ -833,6 +920,9 @@
native_reset_timer_thread(void)
{
timer_thread_id = 0;
+#ifdef BROKEN_PTHREAD_T_PT_LID
- ((struct __pthread_st *)pthread_self())->pt_lid = _lwp_self();
+#endif
}
#ifdef HAVE_SIGALTSTACK