Re: [Qemu-devel] [PATCH RFC v4 7/7] qemu_thread_create: propagate the error to callers to handle

[Fam Zheng]

On Wed, 09/26 18:02, Fei Li wrote:
> diff --git a/util/qemu-thread-posix.c b/util/qemu-thread-posix.c
> index 289af4fab5..8b044e2798 100644
> --- a/util/qemu-thread-posix.c
> +++ b/util/qemu-thread-posix.c
> @@ -15,6 +15,7 @@
>  #include "qemu/atomic.h"
>  #include "qemu/notify.h"
>  #include "qemu-thread-common.h"
> +#include "qapi/error.h"
>  
>  static bool name_threads;
>  
> @@ -504,9 +505,9 @@ static void *qemu_thread_start(void *args)
>      return start_routine(arg);
>  }
>  
> -void qemu_thread_create(QemuThread *thread, const char *name,
> -                       void *(*start_routine)(void*),
> -                       void *arg, int mode)
> +bool qemu_thread_create(QemuThread *thread, const char *name,
> +                        void *(*start_routine)(void *),
> +                        void *arg, int mode, Error **errp)
>  {
>      sigset_t set, oldset;
>      int err;
> @@ -515,7 +516,9 @@ void qemu_thread_create(QemuThread *thread, const char 
> *name,
>  
>      err = pthread_attr_init(&attr);
>      if (err) {
> -        error_exit(err, __func__);
> +        error_setg(errp, "pthread_attr_init failed: %s", strerror(err));

This can use error_setg_errno.

> +        errno = err;

Is errno used anywhere in this series? The windows implementation doesn't set
it.

> +        return false;
>      }
>  
>      if (mode == QEMU_THREAD_DETACHED) {
> @@ -530,16 +533,21 @@ void qemu_thread_create(QemuThread *thread, const char 
> *name,
>      qemu_thread_args->name = g_strdup(name);
>      qemu_thread_args->start_routine = start_routine;
>      qemu_thread_args->arg = arg;
> -
>      err = pthread_create(&thread->thread, &attr,
>                           qemu_thread_start, qemu_thread_args);
> -
> -    if (err)
> -        error_exit(err, __func__);
> +    if (err) {
> +        error_setg(errp, "pthread_create failed: %s", strerror(err));
> +        errno = err;

Same questions here.

> +        pthread_attr_destroy(&attr);
> +        g_free(qemu_thread_args->name);
> +        g_free(qemu_thread_args);
> +        return false;
> +    }
>  
>      pthread_sigmask(SIG_SETMASK, &oldset, NULL);
>  
>      pthread_attr_destroy(&attr);
> +    return true;
>  }
>  
>  void qemu_thread_get_self(QemuThread *thread)
> diff --git a/util/qemu-thread-win32.c b/util/qemu-thread-win32.c
> index 1a27e1cf6f..96e5d19ca3 100644
> --- a/util/qemu-thread-win32.c
> +++ b/util/qemu-thread-win32.c
> @@ -20,6 +20,7 @@
>  #include "qemu/thread.h"
>  #include "qemu/notify.h"
>  #include "qemu-thread-common.h"
> +#include "qapi/error.h"
>  #include <process.h>
>  
>  static bool name_threads;
> @@ -388,9 +389,9 @@ void *qemu_thread_join(QemuThread *thread)
>      return ret;
>  }
>  
> -void qemu_thread_create(QemuThread *thread, const char *name,
> -                       void *(*start_routine)(void *),
> -                       void *arg, int mode)
> +bool qemu_thread_create(QemuThread *thread, const char *name,
> +                        void *(*start_routine)(void *),
> +                        void *arg, int mode, Error **errp)
>  {
>      HANDLE hThread;
>      struct QemuThreadData *data;
> @@ -409,10 +410,17 @@ void qemu_thread_create(QemuThread *thread, const char 
> *name,
>      hThread = (HANDLE) _beginthreadex(NULL, 0, win32_start_routine,
>                                        data, 0, &thread->tid);
>      if (!hThread) {
> -        error_exit(GetLastError(), __func__);
> +        if (data->mode != QEMU_THREAD_DETACHED) {
> +            DeleteCriticalSection(&data->cs);
> +        }
> +        error_setg_win32(errp, GetLastError(),
> +                         "failed to create win32_start_routine");
> +        g_free(data);
> +        return false;
>      }
>      CloseHandle(hThread);
>      thread->data = data;
> +    return true;
>  }
>  
>  void qemu_thread_get_self(QemuThread *thread)

Fam