mirror of
https://github.com/python/cpython
synced 2024-09-05 16:38:56 +00:00
![YAMAMOTO Takashi](/assets/img/avatar_default.png)
Co-authored-by: Brett Cannon <brett@python.org> Co-authored-by: Erlend E. Aasland <erlend.aasland@protonmail.com>
922 lines
24 KiB
C
922 lines
24 KiB
C
#include "pycore_interp.h" // _PyInterpreterState.threads.stacksize
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/* Posix threads interface */
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#include <stdlib.h>
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#include <string.h>
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#if defined(__APPLE__) || defined(HAVE_PTHREAD_DESTRUCTOR)
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#define destructor xxdestructor
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#endif
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#ifndef HAVE_PTHREAD_STUBS
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# include <pthread.h>
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#endif
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#if defined(__APPLE__) || defined(HAVE_PTHREAD_DESTRUCTOR)
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#undef destructor
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#endif
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#include <signal.h>
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#if defined(__linux__)
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# include <sys/syscall.h> /* syscall(SYS_gettid) */
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#elif defined(__FreeBSD__)
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# include <pthread_np.h> /* pthread_getthreadid_np() */
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#elif defined(__OpenBSD__)
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# include <unistd.h> /* getthrid() */
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#elif defined(_AIX)
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# include <sys/thread.h> /* thread_self() */
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#elif defined(__NetBSD__)
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# include <lwp.h> /* _lwp_self() */
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#elif defined(__DragonFly__)
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# include <sys/lwp.h> /* lwp_gettid() */
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#endif
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/* The POSIX spec requires that use of pthread_attr_setstacksize
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be conditional on _POSIX_THREAD_ATTR_STACKSIZE being defined. */
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#ifdef _POSIX_THREAD_ATTR_STACKSIZE
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#ifndef THREAD_STACK_SIZE
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#define THREAD_STACK_SIZE 0 /* use default stack size */
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#endif
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/* The default stack size for new threads on BSD is small enough that
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* we'll get hard crashes instead of 'maximum recursion depth exceeded'
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* exceptions.
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*
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* The default stack size below is the empirically determined minimal stack
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* sizes where a simple recursive function doesn't cause a hard crash.
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*
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* For macOS the value of THREAD_STACK_SIZE is determined in configure.ac
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* as it also depends on the other configure options like chosen sanitizer
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* runtimes.
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*/
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#if defined(__FreeBSD__) && defined(THREAD_STACK_SIZE) && THREAD_STACK_SIZE == 0
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#undef THREAD_STACK_SIZE
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#define THREAD_STACK_SIZE 0x400000
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#endif
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#if defined(_AIX) && defined(THREAD_STACK_SIZE) && THREAD_STACK_SIZE == 0
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#undef THREAD_STACK_SIZE
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#define THREAD_STACK_SIZE 0x200000
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#endif
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/* bpo-38852: test_threading.test_recursion_limit() checks that 1000 recursive
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Python calls (default recursion limit) doesn't crash, but raise a regular
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RecursionError exception. In debug mode, Python function calls allocates
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more memory on the stack, so use a stack of 8 MiB. */
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#if defined(__ANDROID__) && defined(THREAD_STACK_SIZE) && THREAD_STACK_SIZE == 0
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# ifdef Py_DEBUG
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# undef THREAD_STACK_SIZE
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# define THREAD_STACK_SIZE 0x800000
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# endif
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#endif
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#if defined(__VXWORKS__) && defined(THREAD_STACK_SIZE) && THREAD_STACK_SIZE == 0
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#undef THREAD_STACK_SIZE
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#define THREAD_STACK_SIZE 0x100000
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#endif
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/* for safety, ensure a viable minimum stacksize */
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#define THREAD_STACK_MIN 0x8000 /* 32 KiB */
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#else /* !_POSIX_THREAD_ATTR_STACKSIZE */
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#ifdef THREAD_STACK_SIZE
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#error "THREAD_STACK_SIZE defined but _POSIX_THREAD_ATTR_STACKSIZE undefined"
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#endif
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#endif
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/* The POSIX spec says that implementations supporting the sem_*
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family of functions must indicate this by defining
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_POSIX_SEMAPHORES. */
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#ifdef _POSIX_SEMAPHORES
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/* On FreeBSD 4.x, _POSIX_SEMAPHORES is defined empty, so
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we need to add 0 to make it work there as well. */
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#if (_POSIX_SEMAPHORES+0) == -1
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#define HAVE_BROKEN_POSIX_SEMAPHORES
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#else
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#include <semaphore.h>
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#include <errno.h>
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#endif
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#endif
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/* Whether or not to use semaphores directly rather than emulating them with
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* mutexes and condition variables:
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*/
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#if (defined(_POSIX_SEMAPHORES) && !defined(HAVE_BROKEN_POSIX_SEMAPHORES) && \
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(defined(HAVE_SEM_TIMEDWAIT) || defined(HAVE_SEM_CLOCKWAIT)))
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# define USE_SEMAPHORES
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#else
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# undef USE_SEMAPHORES
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#endif
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/* On platforms that don't use standard POSIX threads pthread_sigmask()
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* isn't present. DEC threads uses sigprocmask() instead as do most
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* other UNIX International compliant systems that don't have the full
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* pthread implementation.
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*/
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#if defined(HAVE_PTHREAD_SIGMASK) && !defined(HAVE_BROKEN_PTHREAD_SIGMASK)
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# define SET_THREAD_SIGMASK pthread_sigmask
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#else
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# define SET_THREAD_SIGMASK sigprocmask
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#endif
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/*
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* pthread_cond support
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*/
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#define condattr_monotonic _PyRuntime.threads._condattr_monotonic.ptr
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static void
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init_condattr(void)
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{
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#ifdef CONDATTR_MONOTONIC
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# define ca _PyRuntime.threads._condattr_monotonic.val
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// XXX We need to check the return code?
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pthread_condattr_init(&ca);
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// XXX We need to run pthread_condattr_destroy() during runtime fini.
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if (pthread_condattr_setclock(&ca, CLOCK_MONOTONIC) == 0) {
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condattr_monotonic = &ca; // Use monotonic clock
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}
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# undef ca
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#endif // CONDATTR_MONOTONIC
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}
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int
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_PyThread_cond_init(PyCOND_T *cond)
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{
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return pthread_cond_init(cond, condattr_monotonic);
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}
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void
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_PyThread_cond_after(long long us, struct timespec *abs)
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{
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_PyTime_t timeout = _PyTime_FromMicrosecondsClamp(us);
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_PyTime_t t;
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#ifdef CONDATTR_MONOTONIC
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if (condattr_monotonic) {
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t = _PyTime_GetMonotonicClock();
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}
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else
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#endif
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{
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t = _PyTime_GetSystemClock();
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}
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t = _PyTime_Add(t, timeout);
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_PyTime_AsTimespec_clamp(t, abs);
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}
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/* A pthread mutex isn't sufficient to model the Python lock type
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* because, according to Draft 5 of the docs (P1003.4a/D5), both of the
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* following are undefined:
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* -> a thread tries to lock a mutex it already has locked
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* -> a thread tries to unlock a mutex locked by a different thread
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* pthread mutexes are designed for serializing threads over short pieces
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* of code anyway, so wouldn't be an appropriate implementation of
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* Python's locks regardless.
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*
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* The pthread_lock struct implements a Python lock as a "locked?" bit
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* and a <condition, mutex> pair. In general, if the bit can be acquired
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* instantly, it is, else the pair is used to block the thread until the
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* bit is cleared. 9 May 1994 tim@ksr.com
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*/
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typedef struct {
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char locked; /* 0=unlocked, 1=locked */
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/* a <cond, mutex> pair to handle an acquire of a locked lock */
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pthread_cond_t lock_released;
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pthread_mutex_t mut;
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} pthread_lock;
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#define CHECK_STATUS(name) if (status != 0) { perror(name); error = 1; }
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#define CHECK_STATUS_PTHREAD(name) if (status != 0) { fprintf(stderr, \
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"%s: %s\n", name, strerror(status)); error = 1; }
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/*
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* Initialization for the current runtime.
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*/
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static void
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PyThread__init_thread(void)
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{
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// The library is only initialized once in the process,
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// regardless of how many times the Python runtime is initialized.
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static int lib_initialized = 0;
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if (!lib_initialized) {
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lib_initialized = 1;
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#if defined(_AIX) && defined(__GNUC__)
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extern void pthread_init(void);
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pthread_init();
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#endif
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}
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init_condattr();
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}
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/*
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* Thread support.
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*/
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/* bpo-33015: pythread_callback struct and pythread_wrapper() cast
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"void func(void *)" to "void* func(void *)": always return NULL.
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PyThread_start_new_thread() uses "void func(void *)" type, whereas
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pthread_create() requires a void* return value. */
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typedef struct {
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void (*func) (void *);
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void *arg;
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} pythread_callback;
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static void *
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pythread_wrapper(void *arg)
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{
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/* copy func and func_arg and free the temporary structure */
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pythread_callback *callback = arg;
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void (*func)(void *) = callback->func;
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void *func_arg = callback->arg;
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PyMem_RawFree(arg);
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func(func_arg);
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return NULL;
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}
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unsigned long
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PyThread_start_new_thread(void (*func)(void *), void *arg)
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{
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pthread_t th;
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int status;
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#if defined(THREAD_STACK_SIZE) || defined(PTHREAD_SYSTEM_SCHED_SUPPORTED)
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pthread_attr_t attrs;
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#endif
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#if defined(THREAD_STACK_SIZE)
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size_t tss;
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#endif
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if (!initialized)
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PyThread_init_thread();
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#if defined(THREAD_STACK_SIZE) || defined(PTHREAD_SYSTEM_SCHED_SUPPORTED)
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if (pthread_attr_init(&attrs) != 0)
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return PYTHREAD_INVALID_THREAD_ID;
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#endif
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#if defined(THREAD_STACK_SIZE)
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PyThreadState *tstate = _PyThreadState_GET();
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size_t stacksize = tstate ? tstate->interp->threads.stacksize : 0;
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tss = (stacksize != 0) ? stacksize : THREAD_STACK_SIZE;
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if (tss != 0) {
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if (pthread_attr_setstacksize(&attrs, tss) != 0) {
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pthread_attr_destroy(&attrs);
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return PYTHREAD_INVALID_THREAD_ID;
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}
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}
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#endif
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#if defined(PTHREAD_SYSTEM_SCHED_SUPPORTED)
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pthread_attr_setscope(&attrs, PTHREAD_SCOPE_SYSTEM);
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#endif
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pythread_callback *callback = PyMem_RawMalloc(sizeof(pythread_callback));
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if (callback == NULL) {
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return PYTHREAD_INVALID_THREAD_ID;
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}
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callback->func = func;
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callback->arg = arg;
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status = pthread_create(&th,
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#if defined(THREAD_STACK_SIZE) || defined(PTHREAD_SYSTEM_SCHED_SUPPORTED)
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&attrs,
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#else
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(pthread_attr_t*)NULL,
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#endif
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pythread_wrapper, callback);
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#if defined(THREAD_STACK_SIZE) || defined(PTHREAD_SYSTEM_SCHED_SUPPORTED)
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pthread_attr_destroy(&attrs);
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#endif
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if (status != 0) {
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PyMem_RawFree(callback);
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return PYTHREAD_INVALID_THREAD_ID;
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}
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pthread_detach(th);
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#if SIZEOF_PTHREAD_T <= SIZEOF_LONG
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return (unsigned long) th;
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#else
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return (unsigned long) *(unsigned long *) &th;
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#endif
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}
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/* XXX This implementation is considered (to quote Tim Peters) "inherently
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hosed" because:
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- It does not guarantee the promise that a non-zero integer is returned.
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- The cast to unsigned long is inherently unsafe.
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- It is not clear that the 'volatile' (for AIX?) are any longer necessary.
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*/
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unsigned long
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PyThread_get_thread_ident(void)
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{
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volatile pthread_t threadid;
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if (!initialized)
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PyThread_init_thread();
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threadid = pthread_self();
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return (unsigned long) threadid;
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}
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#ifdef PY_HAVE_THREAD_NATIVE_ID
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unsigned long
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PyThread_get_thread_native_id(void)
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{
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if (!initialized)
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PyThread_init_thread();
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#ifdef __APPLE__
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uint64_t native_id;
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(void) pthread_threadid_np(NULL, &native_id);
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#elif defined(__linux__)
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pid_t native_id;
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native_id = syscall(SYS_gettid);
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#elif defined(__FreeBSD__)
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int native_id;
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native_id = pthread_getthreadid_np();
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#elif defined(__OpenBSD__)
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pid_t native_id;
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native_id = getthrid();
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#elif defined(_AIX)
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tid_t native_id;
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native_id = thread_self();
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#elif defined(__NetBSD__)
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lwpid_t native_id;
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native_id = _lwp_self();
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#elif defined(__DragonFly__)
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lwpid_t native_id;
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native_id = lwp_gettid();
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#endif
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return (unsigned long) native_id;
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}
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#endif
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void _Py_NO_RETURN
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PyThread_exit_thread(void)
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{
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if (!initialized)
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exit(0);
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#if defined(__wasi__)
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/*
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* wasi-threads doesn't have pthread_exit right now
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* cf. https://github.com/WebAssembly/wasi-threads/issues/7
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*/
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abort();
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#else
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pthread_exit(0);
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#endif
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}
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#ifdef USE_SEMAPHORES
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/*
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* Lock support.
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*/
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PyThread_type_lock
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PyThread_allocate_lock(void)
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{
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sem_t *lock;
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int status, error = 0;
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if (!initialized)
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PyThread_init_thread();
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lock = (sem_t *)PyMem_RawMalloc(sizeof(sem_t));
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if (lock) {
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status = sem_init(lock,0,1);
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CHECK_STATUS("sem_init");
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if (error) {
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PyMem_RawFree((void *)lock);
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lock = NULL;
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}
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}
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return (PyThread_type_lock)lock;
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}
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void
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PyThread_free_lock(PyThread_type_lock lock)
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{
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sem_t *thelock = (sem_t *)lock;
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int status, error = 0;
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(void) error; /* silence unused-but-set-variable warning */
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if (!thelock)
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return;
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status = sem_destroy(thelock);
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CHECK_STATUS("sem_destroy");
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PyMem_RawFree((void *)thelock);
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}
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/*
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* As of February 2002, Cygwin thread implementations mistakenly report error
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* codes in the return value of the sem_ calls (like the pthread_ functions).
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* Correct implementations return -1 and put the code in errno. This supports
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* either.
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*/
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static int
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fix_status(int status)
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{
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return (status == -1) ? errno : status;
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}
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PyLockStatus
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PyThread_acquire_lock_timed(PyThread_type_lock lock, PY_TIMEOUT_T microseconds,
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int intr_flag)
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{
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PyLockStatus success;
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sem_t *thelock = (sem_t *)lock;
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int status, error = 0;
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(void) error; /* silence unused-but-set-variable warning */
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_PyTime_t timeout; // relative timeout
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if (microseconds >= 0) {
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// bpo-41710: PyThread_acquire_lock_timed() cannot report timeout
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|
// overflow to the caller, so clamp the timeout to
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// [_PyTime_MIN, _PyTime_MAX].
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//
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// _PyTime_MAX nanoseconds is around 292.3 years.
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//
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// _thread.Lock.acquire() and _thread.RLock.acquire() raise an
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// OverflowError if microseconds is greater than PY_TIMEOUT_MAX.
|
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timeout = _PyTime_FromMicrosecondsClamp(microseconds);
|
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}
|
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else {
|
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timeout = _PyTime_FromNanoseconds(-1);
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}
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|
|
#ifdef HAVE_SEM_CLOCKWAIT
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struct timespec abs_timeout;
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|
// Local scope for deadline
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|
{
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_PyTime_t deadline = _PyTime_Add(_PyTime_GetMonotonicClock(), timeout);
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_PyTime_AsTimespec_clamp(deadline, &abs_timeout);
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}
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#else
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_PyTime_t deadline = 0;
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if (timeout > 0 && !intr_flag) {
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deadline = _PyDeadline_Init(timeout);
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}
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#endif
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|
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while (1) {
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if (timeout > 0) {
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#ifdef HAVE_SEM_CLOCKWAIT
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status = fix_status(sem_clockwait(thelock, CLOCK_MONOTONIC,
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&abs_timeout));
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#else
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_PyTime_t abs_time = _PyTime_Add(_PyTime_GetSystemClock(),
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timeout);
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struct timespec ts;
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_PyTime_AsTimespec_clamp(abs_time, &ts);
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status = fix_status(sem_timedwait(thelock, &ts));
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|
#endif
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|
}
|
|
else if (timeout == 0) {
|
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status = fix_status(sem_trywait(thelock));
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}
|
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else {
|
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status = fix_status(sem_wait(thelock));
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|
}
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|
|
/* Retry if interrupted by a signal, unless the caller wants to be
|
|
notified. */
|
|
if (intr_flag || status != EINTR) {
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|
break;
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}
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|
|
// sem_clockwait() uses an absolute timeout, there is no need
|
|
// to recompute the relative timeout.
|
|
#ifndef HAVE_SEM_CLOCKWAIT
|
|
if (timeout > 0) {
|
|
/* wait interrupted by a signal (EINTR): recompute the timeout */
|
|
timeout = _PyDeadline_Get(deadline);
|
|
if (timeout < 0) {
|
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status = ETIMEDOUT;
|
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break;
|
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}
|
|
}
|
|
#endif
|
|
}
|
|
|
|
/* Don't check the status if we're stopping because of an interrupt. */
|
|
if (!(intr_flag && status == EINTR)) {
|
|
if (timeout > 0) {
|
|
if (status != ETIMEDOUT) {
|
|
#ifdef HAVE_SEM_CLOCKWAIT
|
|
CHECK_STATUS("sem_clockwait");
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|
#else
|
|
CHECK_STATUS("sem_timedwait");
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|
#endif
|
|
}
|
|
}
|
|
else if (timeout == 0) {
|
|
if (status != EAGAIN) {
|
|
CHECK_STATUS("sem_trywait");
|
|
}
|
|
}
|
|
else {
|
|
CHECK_STATUS("sem_wait");
|
|
}
|
|
}
|
|
|
|
if (status == 0) {
|
|
success = PY_LOCK_ACQUIRED;
|
|
} else if (intr_flag && status == EINTR) {
|
|
success = PY_LOCK_INTR;
|
|
} else {
|
|
success = PY_LOCK_FAILURE;
|
|
}
|
|
|
|
return success;
|
|
}
|
|
|
|
void
|
|
PyThread_release_lock(PyThread_type_lock lock)
|
|
{
|
|
sem_t *thelock = (sem_t *)lock;
|
|
int status, error = 0;
|
|
|
|
(void) error; /* silence unused-but-set-variable warning */
|
|
|
|
status = sem_post(thelock);
|
|
CHECK_STATUS("sem_post");
|
|
}
|
|
|
|
#else /* USE_SEMAPHORES */
|
|
|
|
/*
|
|
* Lock support.
|
|
*/
|
|
PyThread_type_lock
|
|
PyThread_allocate_lock(void)
|
|
{
|
|
pthread_lock *lock;
|
|
int status, error = 0;
|
|
|
|
if (!initialized)
|
|
PyThread_init_thread();
|
|
|
|
lock = (pthread_lock *) PyMem_RawCalloc(1, sizeof(pthread_lock));
|
|
if (lock) {
|
|
lock->locked = 0;
|
|
|
|
status = pthread_mutex_init(&lock->mut, NULL);
|
|
CHECK_STATUS_PTHREAD("pthread_mutex_init");
|
|
/* Mark the pthread mutex underlying a Python mutex as
|
|
pure happens-before. We can't simply mark the
|
|
Python-level mutex as a mutex because it can be
|
|
acquired and released in different threads, which
|
|
will cause errors. */
|
|
_Py_ANNOTATE_PURE_HAPPENS_BEFORE_MUTEX(&lock->mut);
|
|
|
|
status = _PyThread_cond_init(&lock->lock_released);
|
|
CHECK_STATUS_PTHREAD("pthread_cond_init");
|
|
|
|
if (error) {
|
|
PyMem_RawFree((void *)lock);
|
|
lock = 0;
|
|
}
|
|
}
|
|
|
|
return (PyThread_type_lock) lock;
|
|
}
|
|
|
|
void
|
|
PyThread_free_lock(PyThread_type_lock lock)
|
|
{
|
|
pthread_lock *thelock = (pthread_lock *)lock;
|
|
int status, error = 0;
|
|
|
|
(void) error; /* silence unused-but-set-variable warning */
|
|
|
|
/* some pthread-like implementations tie the mutex to the cond
|
|
* and must have the cond destroyed first.
|
|
*/
|
|
status = pthread_cond_destroy( &thelock->lock_released );
|
|
CHECK_STATUS_PTHREAD("pthread_cond_destroy");
|
|
|
|
status = pthread_mutex_destroy( &thelock->mut );
|
|
CHECK_STATUS_PTHREAD("pthread_mutex_destroy");
|
|
|
|
PyMem_RawFree((void *)thelock);
|
|
}
|
|
|
|
PyLockStatus
|
|
PyThread_acquire_lock_timed(PyThread_type_lock lock, PY_TIMEOUT_T microseconds,
|
|
int intr_flag)
|
|
{
|
|
PyLockStatus success = PY_LOCK_FAILURE;
|
|
pthread_lock *thelock = (pthread_lock *)lock;
|
|
int status, error = 0;
|
|
|
|
if (microseconds == 0) {
|
|
status = pthread_mutex_trylock( &thelock->mut );
|
|
if (status != EBUSY) {
|
|
CHECK_STATUS_PTHREAD("pthread_mutex_trylock[1]");
|
|
}
|
|
}
|
|
else {
|
|
status = pthread_mutex_lock( &thelock->mut );
|
|
CHECK_STATUS_PTHREAD("pthread_mutex_lock[1]");
|
|
}
|
|
if (status != 0) {
|
|
goto done;
|
|
}
|
|
|
|
if (thelock->locked == 0) {
|
|
success = PY_LOCK_ACQUIRED;
|
|
goto unlock;
|
|
}
|
|
if (microseconds == 0) {
|
|
goto unlock;
|
|
}
|
|
|
|
struct timespec abs_timeout;
|
|
if (microseconds > 0) {
|
|
_PyThread_cond_after(microseconds, &abs_timeout);
|
|
}
|
|
// Continue trying until we get the lock
|
|
|
|
// mut must be locked by me -- part of the condition protocol
|
|
while (1) {
|
|
if (microseconds > 0) {
|
|
status = pthread_cond_timedwait(&thelock->lock_released,
|
|
&thelock->mut, &abs_timeout);
|
|
if (status == 1) {
|
|
break;
|
|
}
|
|
if (status == ETIMEDOUT) {
|
|
break;
|
|
}
|
|
CHECK_STATUS_PTHREAD("pthread_cond_timedwait");
|
|
}
|
|
else {
|
|
status = pthread_cond_wait(
|
|
&thelock->lock_released,
|
|
&thelock->mut);
|
|
CHECK_STATUS_PTHREAD("pthread_cond_wait");
|
|
}
|
|
|
|
if (intr_flag && status == 0 && thelock->locked) {
|
|
// We were woken up, but didn't get the lock. We probably received
|
|
// a signal. Return PY_LOCK_INTR to allow the caller to handle
|
|
// it and retry.
|
|
success = PY_LOCK_INTR;
|
|
break;
|
|
}
|
|
|
|
if (status == 0 && !thelock->locked) {
|
|
success = PY_LOCK_ACQUIRED;
|
|
break;
|
|
}
|
|
|
|
// Wait got interrupted by a signal: retry
|
|
}
|
|
|
|
unlock:
|
|
if (success == PY_LOCK_ACQUIRED) {
|
|
thelock->locked = 1;
|
|
}
|
|
status = pthread_mutex_unlock( &thelock->mut );
|
|
CHECK_STATUS_PTHREAD("pthread_mutex_unlock[1]");
|
|
|
|
done:
|
|
if (error) {
|
|
success = PY_LOCK_FAILURE;
|
|
}
|
|
return success;
|
|
}
|
|
|
|
void
|
|
PyThread_release_lock(PyThread_type_lock lock)
|
|
{
|
|
pthread_lock *thelock = (pthread_lock *)lock;
|
|
int status, error = 0;
|
|
|
|
(void) error; /* silence unused-but-set-variable warning */
|
|
|
|
status = pthread_mutex_lock( &thelock->mut );
|
|
CHECK_STATUS_PTHREAD("pthread_mutex_lock[3]");
|
|
|
|
thelock->locked = 0;
|
|
|
|
/* wake up someone (anyone, if any) waiting on the lock */
|
|
status = pthread_cond_signal( &thelock->lock_released );
|
|
CHECK_STATUS_PTHREAD("pthread_cond_signal");
|
|
|
|
status = pthread_mutex_unlock( &thelock->mut );
|
|
CHECK_STATUS_PTHREAD("pthread_mutex_unlock[3]");
|
|
}
|
|
|
|
#endif /* USE_SEMAPHORES */
|
|
|
|
int
|
|
_PyThread_at_fork_reinit(PyThread_type_lock *lock)
|
|
{
|
|
PyThread_type_lock new_lock = PyThread_allocate_lock();
|
|
if (new_lock == NULL) {
|
|
return -1;
|
|
}
|
|
|
|
/* bpo-6721, bpo-40089: The old lock can be in an inconsistent state.
|
|
fork() can be called in the middle of an operation on the lock done by
|
|
another thread. So don't call PyThread_free_lock(*lock).
|
|
|
|
Leak memory on purpose. Don't release the memory either since the
|
|
address of a mutex is relevant. Putting two mutexes at the same address
|
|
can lead to problems. */
|
|
|
|
*lock = new_lock;
|
|
return 0;
|
|
}
|
|
|
|
int
|
|
PyThread_acquire_lock(PyThread_type_lock lock, int waitflag)
|
|
{
|
|
return PyThread_acquire_lock_timed(lock, waitflag ? -1 : 0, /*intr_flag=*/0);
|
|
}
|
|
|
|
/* set the thread stack size.
|
|
* Return 0 if size is valid, -1 if size is invalid,
|
|
* -2 if setting stack size is not supported.
|
|
*/
|
|
static int
|
|
_pythread_pthread_set_stacksize(size_t size)
|
|
{
|
|
#if defined(THREAD_STACK_SIZE)
|
|
pthread_attr_t attrs;
|
|
size_t tss_min;
|
|
int rc = 0;
|
|
#endif
|
|
|
|
/* set to default */
|
|
if (size == 0) {
|
|
_PyInterpreterState_GET()->threads.stacksize = 0;
|
|
return 0;
|
|
}
|
|
|
|
#if defined(THREAD_STACK_SIZE)
|
|
#if defined(PTHREAD_STACK_MIN)
|
|
tss_min = PTHREAD_STACK_MIN > THREAD_STACK_MIN ? PTHREAD_STACK_MIN
|
|
: THREAD_STACK_MIN;
|
|
#else
|
|
tss_min = THREAD_STACK_MIN;
|
|
#endif
|
|
if (size >= tss_min) {
|
|
/* validate stack size by setting thread attribute */
|
|
if (pthread_attr_init(&attrs) == 0) {
|
|
rc = pthread_attr_setstacksize(&attrs, size);
|
|
pthread_attr_destroy(&attrs);
|
|
if (rc == 0) {
|
|
_PyInterpreterState_GET()->threads.stacksize = size;
|
|
return 0;
|
|
}
|
|
}
|
|
}
|
|
return -1;
|
|
#else
|
|
return -2;
|
|
#endif
|
|
}
|
|
|
|
#define THREAD_SET_STACKSIZE(x) _pythread_pthread_set_stacksize(x)
|
|
|
|
|
|
/* Thread Local Storage (TLS) API
|
|
|
|
This API is DEPRECATED since Python 3.7. See PEP 539 for details.
|
|
*/
|
|
|
|
/* Issue #25658: On platforms where native TLS key is defined in a way that
|
|
cannot be safely cast to int, PyThread_create_key returns immediately a
|
|
failure status and other TLS functions all are no-ops. This indicates
|
|
clearly that the old API is not supported on platforms where it cannot be
|
|
used reliably, and that no effort will be made to add such support.
|
|
|
|
Note: PTHREAD_KEY_T_IS_COMPATIBLE_WITH_INT will be unnecessary after
|
|
removing this API.
|
|
*/
|
|
|
|
int
|
|
PyThread_create_key(void)
|
|
{
|
|
#ifdef PTHREAD_KEY_T_IS_COMPATIBLE_WITH_INT
|
|
pthread_key_t key;
|
|
int fail = pthread_key_create(&key, NULL);
|
|
if (fail)
|
|
return -1;
|
|
if (key > INT_MAX) {
|
|
/* Issue #22206: handle integer overflow */
|
|
pthread_key_delete(key);
|
|
errno = ENOMEM;
|
|
return -1;
|
|
}
|
|
return (int)key;
|
|
#else
|
|
return -1; /* never return valid key value. */
|
|
#endif
|
|
}
|
|
|
|
void
|
|
PyThread_delete_key(int key)
|
|
{
|
|
#ifdef PTHREAD_KEY_T_IS_COMPATIBLE_WITH_INT
|
|
pthread_key_delete(key);
|
|
#endif
|
|
}
|
|
|
|
void
|
|
PyThread_delete_key_value(int key)
|
|
{
|
|
#ifdef PTHREAD_KEY_T_IS_COMPATIBLE_WITH_INT
|
|
pthread_setspecific(key, NULL);
|
|
#endif
|
|
}
|
|
|
|
int
|
|
PyThread_set_key_value(int key, void *value)
|
|
{
|
|
#ifdef PTHREAD_KEY_T_IS_COMPATIBLE_WITH_INT
|
|
int fail = pthread_setspecific(key, value);
|
|
return fail ? -1 : 0;
|
|
#else
|
|
return -1;
|
|
#endif
|
|
}
|
|
|
|
void *
|
|
PyThread_get_key_value(int key)
|
|
{
|
|
#ifdef PTHREAD_KEY_T_IS_COMPATIBLE_WITH_INT
|
|
return pthread_getspecific(key);
|
|
#else
|
|
return NULL;
|
|
#endif
|
|
}
|
|
|
|
|
|
void
|
|
PyThread_ReInitTLS(void)
|
|
{
|
|
}
|
|
|
|
|
|
/* Thread Specific Storage (TSS) API
|
|
|
|
Platform-specific components of TSS API implementation.
|
|
*/
|
|
|
|
int
|
|
PyThread_tss_create(Py_tss_t *key)
|
|
{
|
|
assert(key != NULL);
|
|
/* If the key has been created, function is silently skipped. */
|
|
if (key->_is_initialized) {
|
|
return 0;
|
|
}
|
|
|
|
int fail = pthread_key_create(&(key->_key), NULL);
|
|
if (fail) {
|
|
return -1;
|
|
}
|
|
key->_is_initialized = 1;
|
|
return 0;
|
|
}
|
|
|
|
void
|
|
PyThread_tss_delete(Py_tss_t *key)
|
|
{
|
|
assert(key != NULL);
|
|
/* If the key has not been created, function is silently skipped. */
|
|
if (!key->_is_initialized) {
|
|
return;
|
|
}
|
|
|
|
pthread_key_delete(key->_key);
|
|
/* pthread has not provided the defined invalid value for the key. */
|
|
key->_is_initialized = 0;
|
|
}
|
|
|
|
int
|
|
PyThread_tss_set(Py_tss_t *key, void *value)
|
|
{
|
|
assert(key != NULL);
|
|
int fail = pthread_setspecific(key->_key, value);
|
|
return fail ? -1 : 0;
|
|
}
|
|
|
|
void *
|
|
PyThread_tss_get(Py_tss_t *key)
|
|
{
|
|
assert(key != NULL);
|
|
return pthread_getspecific(key->_key);
|
|
}
|