Re: [PATCH v1 1/5] Add a mutex to guarantee single writer to qemu_logfile handle.

[Richard Henderson]

On 11/12/19 4:01 PM, Robert Foley wrote:
> Also added qemu_logfile_init() for initializing the logfile mutex.
> 
> Signed-off-by: Robert Foley <address@hidden>
> ---
> v1
>     - changed qemu_logfile_init() to use __constructor__.
> ---
>  util/log.c | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
> 
> diff --git a/util/log.c b/util/log.c
> index 1ca13059ee..c25643dc99 100644
> --- a/util/log.c
> +++ b/util/log.c
> @@ -24,8 +24,10 @@
>  #include "qapi/error.h"
>  #include "qemu/cutils.h"
>  #include "trace/control.h"
> +#include "qemu/thread.h"
>  
>  static char *logfilename;
> +static QemuMutex qemu_logfile_mutex;
>  FILE *qemu_logfile;
>  int qemu_loglevel;
>  static int log_append = 0;
> @@ -49,6 +51,11 @@ int qemu_log(const char *fmt, ...)
>      return ret;
>  }
>  
> +static void __attribute__((__constructor__)) qemu_logfile_init(void)
> +{
> +    qemu_mutex_init(&qemu_logfile_mutex);
> +}
> +
>  static bool log_uses_own_buffers;
>  
>  /* enable or disable low levels log */
> @@ -58,6 +65,9 @@ void qemu_set_log(int log_flags)
>  #ifdef CONFIG_TRACE_LOG
>      qemu_loglevel |= LOG_TRACE;
>  #endif
> +
> +    g_assert(qemu_logfile_mutex.initialized);

Why the asserts?

If you want a runtime test, then use the test to initialize it.
Otherwise, trust the constructor.


r~