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authorAustin Foxley <austinf@cetoncorp.com>2009-10-17 12:26:24 -0700
committerAustin Foxley <austinf@cetoncorp.com>2009-10-17 12:26:24 -0700
commitc68d0fa2d88fc2134a38d99e7e944828384a7671 (patch)
tree6596943bd1c77f18d6e49d4153ddd3f3d67b49f5 /libpthread/nptl/pthread_create.c
parent9a03e98a3b418f33c347a6023e9320f3a42cb9e4 (diff)
libpthread/nptl: core of the "Native Posix Threading Library" for uClibc
targetting arm,sh,i386,mips,sparc for now Signed-off-by: Austin Foxley <austinf@cetoncorp.com>
Diffstat (limited to 'libpthread/nptl/pthread_create.c')
-rw-r--r--libpthread/nptl/pthread_create.c484
1 files changed, 484 insertions, 0 deletions
diff --git a/libpthread/nptl/pthread_create.c b/libpthread/nptl/pthread_create.c
new file mode 100644
index 000000000..81da5b93a
--- /dev/null
+++ b/libpthread/nptl/pthread_create.c
@@ -0,0 +1,484 @@
+/* Copyright (C) 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <errno.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+#include "pthreadP.h"
+#include <hp-timing.h>
+#include <ldsodefs.h>
+#include <atomic.h>
+#include <libc-internal.h>
+#include <resolv.h>
+
+
+/* Local function to start thread and handle cleanup. */
+static int start_thread (void *arg);
+
+
+/* Nozero if debugging mode is enabled. */
+int __pthread_debug;
+
+/* Globally enabled events. */
+static td_thr_events_t __nptl_threads_events;
+
+/* Pointer to descriptor with the last event. */
+static struct pthread *__nptl_last_event;
+
+/* Number of threads running. */
+unsigned int __nptl_nthreads = 1;
+
+
+/* Code to allocate and deallocate a stack. */
+#include "allocatestack.c"
+
+/* Code to create the thread. */
+#include "createthread.c"
+
+
+struct pthread *
+internal_function
+__find_in_stack_list (pd)
+ struct pthread *pd;
+{
+ list_t *entry;
+ struct pthread *result = NULL;
+
+ lll_lock (stack_cache_lock);
+
+ list_for_each (entry, &stack_used)
+ {
+ struct pthread *curp;
+
+ curp = list_entry (entry, struct pthread, list);
+ if (curp == pd)
+ {
+ result = curp;
+ break;
+ }
+ }
+
+ if (result == NULL)
+ list_for_each (entry, &__stack_user)
+ {
+ struct pthread *curp;
+
+ curp = list_entry (entry, struct pthread, list);
+ if (curp == pd)
+ {
+ result = curp;
+ break;
+ }
+ }
+
+ lll_unlock (stack_cache_lock);
+
+ return result;
+}
+
+
+/* Deallocate POSIX thread-local-storage. */
+void
+attribute_hidden
+__nptl_deallocate_tsd (void)
+{
+ struct pthread *self = THREAD_SELF;
+
+ /* Maybe no data was ever allocated. This happens often so we have
+ a flag for this. */
+ if (THREAD_GETMEM (self, specific_used))
+ {
+ size_t round;
+ size_t cnt;
+
+ round = 0;
+ do
+ {
+ size_t idx;
+
+ /* So far no new nonzero data entry. */
+ THREAD_SETMEM (self, specific_used, false);
+
+ for (cnt = idx = 0; cnt < PTHREAD_KEY_1STLEVEL_SIZE; ++cnt)
+ {
+ struct pthread_key_data *level2;
+
+ level2 = THREAD_GETMEM_NC (self, specific, cnt);
+
+ if (level2 != NULL)
+ {
+ size_t inner;
+
+ for (inner = 0; inner < PTHREAD_KEY_2NDLEVEL_SIZE;
+ ++inner, ++idx)
+ {
+ void *data = level2[inner].data;
+
+ if (data != NULL)
+ {
+ /* Always clear the data. */
+ level2[inner].data = NULL;
+
+ /* Make sure the data corresponds to a valid
+ key. This test fails if the key was
+ deallocated and also if it was
+ re-allocated. It is the user's
+ responsibility to free the memory in this
+ case. */
+ if (level2[inner].seq
+ == __pthread_keys[idx].seq
+ /* It is not necessary to register a destructor
+ function. */
+ && __pthread_keys[idx].destr != NULL)
+ /* Call the user-provided destructor. */
+ __pthread_keys[idx].destr (data);
+ }
+ }
+ }
+ else
+ idx += PTHREAD_KEY_1STLEVEL_SIZE;
+ }
+
+ if (THREAD_GETMEM (self, specific_used) == 0)
+ /* No data has been modified. */
+ goto just_free;
+ }
+ /* We only repeat the process a fixed number of times. */
+ while (__builtin_expect (++round < PTHREAD_DESTRUCTOR_ITERATIONS, 0));
+
+ /* Just clear the memory of the first block for reuse. */
+ memset (&THREAD_SELF->specific_1stblock, '\0',
+ sizeof (self->specific_1stblock));
+
+ just_free:
+ /* Free the memory for the other blocks. */
+ for (cnt = 1; cnt < PTHREAD_KEY_1STLEVEL_SIZE; ++cnt)
+ {
+ struct pthread_key_data *level2;
+
+ level2 = THREAD_GETMEM_NC (self, specific, cnt);
+ if (level2 != NULL)
+ {
+ /* The first block is allocated as part of the thread
+ descriptor. */
+ free (level2);
+ THREAD_SETMEM_NC (self, specific, cnt, NULL);
+ }
+ }
+
+ THREAD_SETMEM (self, specific_used, false);
+ }
+}
+
+
+/* Deallocate a thread's stack after optionally making sure the thread
+ descriptor is still valid. */
+void
+internal_function
+__free_tcb (struct pthread *pd)
+{
+ /* The thread is exiting now. */
+ if (__builtin_expect (atomic_bit_test_set (&pd->cancelhandling,
+ TERMINATED_BIT) == 0, 1))
+ {
+ /* Remove the descriptor from the list. */
+ if (DEBUGGING_P && __find_in_stack_list (pd) == NULL)
+ /* Something is really wrong. The descriptor for a still
+ running thread is gone. */
+ abort ();
+
+ /* Queue the stack memory block for reuse and exit the process. The
+ kernel will signal via writing to the address returned by
+ QUEUE-STACK when the stack is available. */
+ __deallocate_stack (pd);
+ }
+}
+
+
+static int
+start_thread (void *arg)
+{
+ struct pthread *pd = (struct pthread *) arg;
+
+#if HP_TIMING_AVAIL
+ /* Remember the time when the thread was started. */
+ hp_timing_t now;
+ HP_TIMING_NOW (now);
+ THREAD_SETMEM (pd, cpuclock_offset, now);
+#endif
+
+ /* Initialize resolver state pointer. */
+ __resp = &pd->res;
+
+ /* This is where the try/finally block should be created. For
+ compilers without that support we do use setjmp. */
+ struct pthread_unwind_buf unwind_buf;
+
+ /* No previous handlers. */
+ unwind_buf.priv.data.prev = NULL;
+ unwind_buf.priv.data.cleanup = NULL;
+
+ int not_first_call;
+ not_first_call = setjmp ((struct __jmp_buf_tag *) unwind_buf.cancel_jmp_buf);
+ if (__builtin_expect (! not_first_call, 1))
+ {
+ /* Store the new cleanup handler info. */
+ THREAD_SETMEM (pd, cleanup_jmp_buf, &unwind_buf);
+
+ if (__builtin_expect (pd->stopped_start, 0))
+ {
+ int oldtype = CANCEL_ASYNC ();
+
+ /* Get the lock the parent locked to force synchronization. */
+ lll_lock (pd->lock);
+ /* And give it up right away. */
+ lll_unlock (pd->lock);
+
+ CANCEL_RESET (oldtype);
+ }
+
+ /* Run the code the user provided. */
+#ifdef CALL_THREAD_FCT
+ THREAD_SETMEM (pd, result, CALL_THREAD_FCT (pd));
+#else
+ THREAD_SETMEM (pd, result, pd->start_routine (pd->arg));
+#endif
+ }
+
+ /* Run the destructor for the thread-local data. */
+ __nptl_deallocate_tsd ();
+
+ /* If this is the last thread we terminate the process now. We
+ do not notify the debugger, it might just irritate it if there
+ is no thread left. */
+ if (__builtin_expect (atomic_decrement_and_test (&__nptl_nthreads), 0))
+ /* This was the last thread. */
+ exit (0);
+
+ /* Report the death of the thread if this is wanted. */
+ if (__builtin_expect (pd->report_events, 0))
+ {
+ /* See whether TD_DEATH is in any of the mask. */
+ const int idx = __td_eventword (TD_DEATH);
+ const uint32_t mask = __td_eventmask (TD_DEATH);
+
+ if ((mask & (__nptl_threads_events.event_bits[idx]
+ | pd->eventbuf.eventmask.event_bits[idx])) != 0)
+ {
+ /* Yep, we have to signal the death. Add the descriptor to
+ the list but only if it is not already on it. */
+ if (pd->nextevent == NULL)
+ {
+ pd->eventbuf.eventnum = TD_DEATH;
+ pd->eventbuf.eventdata = pd;
+
+ do
+ pd->nextevent = __nptl_last_event;
+ while (atomic_compare_and_exchange_bool_acq (&__nptl_last_event,
+ pd, pd->nextevent));
+ }
+
+ /* Now call the function to signal the event. */
+ __nptl_death_event ();
+ }
+ }
+
+ /* The thread is exiting now. Don't set this bit until after we've hit
+ the event-reporting breakpoint, so that td_thr_get_info on us while at
+ the breakpoint reports TD_THR_RUN state rather than TD_THR_ZOMBIE. */
+ atomic_bit_set (&pd->cancelhandling, EXITING_BIT);
+
+ /* If the thread is detached free the TCB. */
+ if (IS_DETACHED (pd))
+ /* Free the TCB. */
+ __free_tcb (pd);
+
+ /* We cannot call '_exit' here. '_exit' will terminate the process.
+
+ The 'exit' implementation in the kernel will signal when the
+ process is really dead since 'clone' got passed the CLONE_CLEARTID
+ flag. The 'tid' field in the TCB will be set to zero.
+
+ The exit code is zero since in case all threads exit by calling
+ 'pthread_exit' the exit status must be 0 (zero). */
+ __exit_thread_inline (0);
+
+ /* NOTREACHED */
+ return 0;
+}
+
+
+/* Default thread attributes for the case when the user does not
+ provide any. */
+static const struct pthread_attr default_attr =
+ {
+ /* Just some value > 0 which gets rounded to the nearest page size. */
+ .guardsize = 1,
+ };
+
+
+int
+__pthread_create_2_1 (newthread, attr, start_routine, arg)
+ pthread_t *newthread;
+ const pthread_attr_t *attr;
+ void *(*start_routine) (void *);
+ void *arg;
+{
+ STACK_VARIABLES;
+
+ const struct pthread_attr *iattr = (struct pthread_attr *) attr;
+ if (iattr == NULL)
+ /* Is this the best idea? On NUMA machines this could mean
+ accessing far-away memory. */
+ iattr = &default_attr;
+
+ struct pthread *pd = 0;
+ int err = ALLOCATE_STACK (iattr, &pd);
+ if (__builtin_expect (err != 0, 0))
+ /* Something went wrong. Maybe a parameter of the attributes is
+ invalid or we could not allocate memory. */
+ return err;
+
+
+ /* Initialize the TCB. All initializations with zero should be
+ performed in 'get_cached_stack'. This way we avoid doing this if
+ the stack freshly allocated with 'mmap'. */
+
+#ifdef TLS_TCB_AT_TP
+ /* Reference to the TCB itself. */
+ pd->header.self = pd;
+
+ /* Self-reference for TLS. */
+ pd->header.tcb = pd;
+#endif
+
+ /* Store the address of the start routine and the parameter. Since
+ we do not start the function directly the stillborn thread will
+ get the information from its thread descriptor. */
+ pd->start_routine = start_routine;
+ pd->arg = arg;
+
+ /* Copy the thread attribute flags. */
+ struct pthread *self = THREAD_SELF;
+ pd->flags = ((iattr->flags & ~(ATTR_FLAG_SCHED_SET | ATTR_FLAG_POLICY_SET))
+ | (self->flags & (ATTR_FLAG_SCHED_SET | ATTR_FLAG_POLICY_SET)));
+
+ /* Initialize the field for the ID of the thread which is waiting
+ for us. This is a self-reference in case the thread is created
+ detached. */
+ pd->joinid = iattr->flags & ATTR_FLAG_DETACHSTATE ? pd : NULL;
+
+ /* The debug events are inherited from the parent. */
+ pd->eventbuf = self->eventbuf;
+
+
+ /* Copy the parent's scheduling parameters. The flags will say what
+ is valid and what is not. */
+ pd->schedpolicy = self->schedpolicy;
+ pd->schedparam = self->schedparam;
+
+ /* Copy the stack guard canary. */
+#ifdef THREAD_COPY_STACK_GUARD
+ THREAD_COPY_STACK_GUARD (pd);
+#endif
+
+ /* Determine scheduling parameters for the thread. */
+ if (attr != NULL
+ && __builtin_expect ((iattr->flags & ATTR_FLAG_NOTINHERITSCHED) != 0, 0)
+ && (iattr->flags & (ATTR_FLAG_SCHED_SET | ATTR_FLAG_POLICY_SET)) != 0)
+ {
+ INTERNAL_SYSCALL_DECL (scerr);
+
+ /* Use the scheduling parameters the user provided. */
+ if (iattr->flags & ATTR_FLAG_POLICY_SET)
+ pd->schedpolicy = iattr->schedpolicy;
+ else if ((pd->flags & ATTR_FLAG_POLICY_SET) == 0)
+ {
+ pd->schedpolicy = INTERNAL_SYSCALL (sched_getscheduler, scerr, 1, 0);
+ pd->flags |= ATTR_FLAG_POLICY_SET;
+ }
+
+ if (iattr->flags & ATTR_FLAG_SCHED_SET)
+ memcpy (&pd->schedparam, &iattr->schedparam,
+ sizeof (struct sched_param));
+ else if ((pd->flags & ATTR_FLAG_SCHED_SET) == 0)
+ {
+ INTERNAL_SYSCALL (sched_getparam, scerr, 2, 0, &pd->schedparam);
+ pd->flags |= ATTR_FLAG_SCHED_SET;
+ }
+
+ /* Check for valid priorities. */
+ int minprio = INTERNAL_SYSCALL (sched_get_priority_min, scerr, 1,
+ iattr->schedpolicy);
+ int maxprio = INTERNAL_SYSCALL (sched_get_priority_max, scerr, 1,
+ iattr->schedpolicy);
+ if (pd->schedparam.sched_priority < minprio
+ || pd->schedparam.sched_priority > maxprio)
+ {
+ err = EINVAL;
+ goto errout;
+ }
+ }
+
+ /* Pass the descriptor to the caller. */
+ *newthread = (pthread_t) pd;
+
+ /* Remember whether the thread is detached or not. In case of an
+ error we have to free the stacks of non-detached stillborn
+ threads. */
+ bool is_detached = IS_DETACHED (pd);
+
+ /* Start the thread. */
+ err = create_thread (pd, iattr, STACK_VARIABLES_ARGS);
+ if (err != 0)
+ {
+ /* Something went wrong. Free the resources. */
+ if (!is_detached)
+ {
+ errout:
+ __deallocate_stack (pd);
+ }
+ return err;
+ }
+
+ return 0;
+}
+weak_alias(__pthread_create_2_1, pthread_create)
+
+/* Information for libthread_db. */
+
+#include "../nptl_db/db_info.c"
+
+/* If pthread_create is present, libgcc_eh.a and libsupc++.a expects some other POSIX thread
+ functions to be present as well. */
+PTHREAD_STATIC_FN_REQUIRE (pthread_mutex_lock)
+PTHREAD_STATIC_FN_REQUIRE (pthread_mutex_unlock)
+
+PTHREAD_STATIC_FN_REQUIRE (pthread_once)
+PTHREAD_STATIC_FN_REQUIRE (pthread_cancel)
+
+PTHREAD_STATIC_FN_REQUIRE (pthread_key_create)
+PTHREAD_STATIC_FN_REQUIRE (pthread_setspecific)
+PTHREAD_STATIC_FN_REQUIRE (pthread_getspecific)
+
+/* UCLIBC_MUTEX_xxx macros expects to have these as well */
+PTHREAD_STATIC_FN_REQUIRE (pthread_mutex_init)
+PTHREAD_STATIC_FN_REQUIRE (_pthread_cleanup_push_defer)
+PTHREAD_STATIC_FN_REQUIRE (_pthread_cleanup_pop_restore)