[Qemu-devel] Re: [5055] Handle terminating signals (Gerd Hoffmann)

[Jan Kiszka <jan.kiszka@siemens.com>]

Jan Kiszka wrote:
> Anthony Liguori wrote:
>> Revision: 5055
>>           http://svn.sv.gnu.org/viewvc/?view=rev&root=qemu&revision=5055
>> Author:   aliguori
>> Date:     2008-08-21 20:08:03 +0000 (Thu, 21 Aug 2008)
>>
>> Log Message:
>> -----------
>> Handle terminating signals (Gerd Hoffmann)
>>
>> This patch makes qemu handle signals better.  It sets the request_shutdown
>> flag, making the main_loop exit and qemu taking the usual exit route, with
>> atexit handlers being called and so on, instead of qemu just being killed
>> by the signal.
>>
>> To avoid calling vm_start() from the signal handler main_loop() got an
>> additional check so qemu_system_shutdown_request() works even when the
>> vm is in stopped state.
>>
>> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
>> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
>>
> 
> ...
> 
>> Modified: trunk/vl.c
>> ===================================================================
>> --- trunk/vl.c	2008-08-21 19:33:09 UTC (rev 5054)
>> +++ trunk/vl.c	2008-08-21 20:08:03 UTC (rev 5055)
>> @@ -7621,6 +7621,8 @@
>>                  timeout = 0;
>>              }
>>          } else {
>> +            if (shutdown_requested)
>> +                break;
>>              timeout = 10;
>>          }
>>  #ifdef CONFIG_PROFILER
> 
> Could we define the policy that no patch is merged which introduces new
> compiler warnings? Fix below remove the one caused by the hunk above,
> but it still leaves some doubts for the semi-informed reader because the
> "if (shutdown_requested)" block under vm_running also checks for
> no_shutdown. Please confirm that leaving it out here was by intention.
> 
> Jan
> 
> --------
> 
> Always return EXCP_INTERRUPT when leaving main_loop due to
> shutdown_requested.
> 
> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
> ---
>  vl.c |    4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> Index: b/vl.c
> ===================================================================
> --- a/vl.c
> +++ b/vl.c
> @@ -7624,8 +7624,10 @@ static int main_loop(void)
>                  timeout = 0;
>              }
>          } else {
> -            if (shutdown_requested)
> +            if (shutdown_requested) {
> +                ret = EXCP_INTERRUPT;
>                  break;
> +            }
>              timeout = 10;
>          }
>  #ifdef CONFIG_PROFILER

After discussing how this issue slipped in, I think it was forgotten to
actually merge the fix... :->

Jan

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