Re: [Qemu-devel] [PATCH 1/5] do not call g_thread_init() for glib >= 2.31

[Stefan Hajnoczi]

On Tue, Apr 29, 2014 at 10:02:24AM +0400, Michael Tokarev wrote:
> glib >= 2.31 always enables thread support and g_thread_supported()
> is #defined to 1, there's no need to call g_thread_init() anymore,
> and it definitely does not need to report error which never happens.
> Keep code for old < 2.31 glibc anyway for now, just #ifdef it
> differently.
> 
> Signed-off-by: Michael Tokarev 
> ---
>  coroutine-gthread.c |7 ++-
>  util/osdep.c|   21 +
>  2 files changed, 11 insertions(+), 17 deletions(-)

Reviewed-by: Stefan Hajnoczi 

Re: [Qemu-devel] [PATCH 1/5] do not call g_thread_init() for glib >= 2.31

[Christophe Fergeau]

On Tue, Apr 29, 2014 at 10:02:24AM +0400, Michael Tokarev wrote:
> glib >= 2.31 always enables thread support and g_thread_supported()
> is #defined to 1, there's no need to call g_thread_init() anymore,
> and it definitely does not need to report error which never happens.
> Keep code for old < 2.31 glibc anyway for now, just #ifdef it
> differently.

This looks good to me, ACK

> 
> Signed-off-by: Michael Tokarev 
> ---
>  coroutine-gthread.c |7 ++-
>  util/osdep.c|   21 +
>  2 files changed, 11 insertions(+), 17 deletions(-)
> 
> diff --git a/coroutine-gthread.c b/coroutine-gthread.c
> index d3e5b99..a61efe0 100644
> --- a/coroutine-gthread.c
> +++ b/coroutine-gthread.c
> @@ -115,14 +115,11 @@ static inline GThread *create_thread(GThreadFunc func, 
> gpointer data)
>  
>  static void __attribute__((constructor)) coroutine_init(void)
>  {
> -if (!g_thread_supported()) {
>  #if !GLIB_CHECK_VERSION(2, 31, 0)
> +if (!g_thread_supported()) {
>  g_thread_init(NULL);
> -#else
> -fprintf(stderr, "glib threading failed to initialize.\n");
> -exit(1);
> -#endif
>  }
> +#endif
>  
>  init_coroutine_cond();
>  }
> diff --git a/util/osdep.c b/util/osdep.c
> index a9029f8..b2bd154 100644
> --- a/util/osdep.c
> +++ b/util/osdep.c
> @@ -436,23 +436,20 @@ int socket_init(void)
>  return 0;
>  }
>  
> -/* Ensure that glib is running in multi-threaded mode */
> +#if !GLIB_CHECK_VERSION(2, 31, 0)
> +/* Ensure that glib is running in multi-threaded mode
> + * Old versions of glib require explicit initialization.  Failure to do
> + * this results in the single-threaded code paths being taken inside
> + * glib.  For example, the g_slice allocator will not be thread-safe
> + * and cause crashes.
> + */
>  static void __attribute__((constructor)) thread_init(void)
>  {
>  if (!g_thread_supported()) {
> -#if !GLIB_CHECK_VERSION(2, 31, 0)
> -/* Old versions of glib require explicit initialization.  Failure to 
> do
> - * this results in the single-threaded code paths being taken inside
> - * glib.  For example, the g_slice allocator will not be thread-safe
> - * and cause crashes.
> - */
> -g_thread_init(NULL);
> -#else
> -fprintf(stderr, "glib threading failed to initialize.\n");
> -exit(1);
> -#endif
> +   g_thread_init(NULL);
>  }
>  }
> +#endif
>  
>  #ifndef CONFIG_IOVEC
>  /* helper function for iov_send_recv() */
> -- 
> 1.7.10.4
> 

[Qemu-devel] [PATCH 1/5] do not call g_thread_init() for glib >= 2.31

[Michael Tokarev]

glib >= 2.31 always enables thread support and g_thread_supported()
is #defined to 1, there's no need to call g_thread_init() anymore,
and it definitely does not need to report error which never happens.
Keep code for old < 2.31 glibc anyway for now, just #ifdef it
differently.

Signed-off-by: Michael Tokarev 
---
 coroutine-gthread.c |7 ++-
 util/osdep.c|   21 +
 2 files changed, 11 insertions(+), 17 deletions(-)

diff --git a/coroutine-gthread.c b/coroutine-gthread.c
index d3e5b99..a61efe0 100644
--- a/coroutine-gthread.c
+++ b/coroutine-gthread.c
@@ -115,14 +115,11 @@ static inline GThread *create_thread(GThreadFunc func, 
gpointer data)
 
 static void __attribute__((constructor)) coroutine_init(void)
 {
-if (!g_thread_supported()) {
 #if !GLIB_CHECK_VERSION(2, 31, 0)
+if (!g_thread_supported()) {
 g_thread_init(NULL);
-#else
-fprintf(stderr, "glib threading failed to initialize.\n");
-exit(1);
-#endif
 }
+#endif
 
 init_coroutine_cond();
 }
diff --git a/util/osdep.c b/util/osdep.c
index a9029f8..b2bd154 100644
--- a/util/osdep.c
+++ b/util/osdep.c
@@ -436,23 +436,20 @@ int socket_init(void)
 return 0;
 }
 
-/* Ensure that glib is running in multi-threaded mode */
+#if !GLIB_CHECK_VERSION(2, 31, 0)
+/* Ensure that glib is running in multi-threaded mode
+ * Old versions of glib require explicit initialization.  Failure to do
+ * this results in the single-threaded code paths being taken inside
+ * glib.  For example, the g_slice allocator will not be thread-safe
+ * and cause crashes.
+ */
 static void __attribute__((constructor)) thread_init(void)
 {
 if (!g_thread_supported()) {
-#if !GLIB_CHECK_VERSION(2, 31, 0)
-/* Old versions of glib require explicit initialization.  Failure to do
- * this results in the single-threaded code paths being taken inside
- * glib.  For example, the g_slice allocator will not be thread-safe
- * and cause crashes.
- */
-g_thread_init(NULL);
-#else
-fprintf(stderr, "glib threading failed to initialize.\n");
-exit(1);
-#endif
+   g_thread_init(NULL);
 }
 }
+#endif
 
 #ifndef CONFIG_IOVEC
 /* helper function for iov_send_recv() */
-- 
1.7.10.4