[PATCH] makedumpfile: Fix a bug when multi-threads feature meets enospace

[Zhou Wenjian]

ping...


On 01/29/2018 08:54 PM, Zhou Wenjian wrote:
> Currently, when multi-threads feature meets enospace error,
> the main thread will call pthread_join(). However, there is one
> thread doing while{} and won't stop.
>
>                  pthread_mutex_lock(&info->page_data_mutex);
>                  while (page_data_buf[index].used != FALSE) {
>                          index = (index + 1) % info->num_buffers;
>                  }
>                  page_data_buf[index].used = TRUE;
>                  pthread_mutex_unlock(&info->page_data_mutex);
>
> Then makedumpfile hangs.
>
> This patch add a cancel point in while{}.
>
> Signed-off-by: Zhou Wenjian <zhouwj.fi at gmail.com>
> ---
>   makedumpfile.c | 4 +++-
>   1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/makedumpfile.c b/makedumpfile.c
> index ed138d3..f7ad50c 100644
> --- a/makedumpfile.c
> +++ b/makedumpfile.c
> @@ -7731,11 +7731,13 @@ kdump_thread_function_cyclic(void *arg) {
>   		buf_ready = FALSE;
>   
>   		pthread_mutex_lock(&info->page_data_mutex);
> +		pthread_cleanup_push(pthread_mutex_unlock, &info->page_data_mutex);
>   		while (page_data_buf[index].used != FALSE) {
> +			pthread_testcancel();
>   			index = (index + 1) % info->num_buffers;
>   		}
>   		page_data_buf[index].used = TRUE;
> -		pthread_mutex_unlock(&info->page_data_mutex);
> +		pthread_cleanup_pop(1);
>   
>   		while (buf_ready == FALSE) {
>   			pthread_testcancel();

-- 
Thanks
Zhou