| Message ID | 14585f602461dbefb3adaf16591ce5e5@whitewinterwolf.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Sat, Mar 18, 2017 at 02:41:16PM +0100, Simon wrote: > Hi, > > The patch below adds the new command-line option `-powerdown' which > changes the behavior for both SIGHUP and SIGINT signals to cause a clean > power down of the guest using an ACPI shutdown request. If you need to add command line arguments IMHO this feature becomes much less interesting - just use the QEMU monitor instead of inventing an adhoc way to achieve something the monitor already does. The value of using a signal handler comes from the fact that it would be unconditionally available no matter what command line args were added. Regards, Daniel
Daniel P. Berrange: > On Sat, Mar 18, 2017 at 02:41:16PM +0100, Simon wrote: >> Hi, >> >> The patch below adds the new command-line option `-powerdown' which >> changes the behavior for both SIGHUP and SIGINT signals to cause a >> clean >> power down of the guest using an ACPI shutdown request. > > If you need to add command line arguments IMHO this feature becomes > much less interesting - just use the QEMU monitor instead of inventing > an adhoc way to achieve something the monitor already does. The value > of > using a signal handler comes from the fact that it would be > unconditionally > available no matter what command line args were added. Hi Daniel, Thank you for taking the time to answer me. I am currently using the monitor to achieve this functionality, and this boils down into doing something similar to this: --------- 8< ---------------- if ! type 'socat' >/dev/null 2>&1 then echo "You must install 'socat'." >&2 exit 1 fi files=$( ps -e -o args | awk '$1 ~ /qemu-system-/' \ | sed 's/.* -monitor unix:\([^,]*\).*/\1/;t;s/.*//' ) IFS=' ' for f in $files do echo 'system_powerdown' | socat "UNIX-CONNECT:${f}" - done --------- 8< ---------------- In other words I check that required software is properly installed, parse `ps' output to extract the path to the monitor socket file when it is available, and pipe the `system_powerdown' command into it to cleanly shut the VM down. As a matter of comparison, here the same functionality implemented using Unix signals instead of the monitor socket files: --------- 8< ---------------- pkill -HUP qemu-system- --------- 8< ---------------- Maybe it is just my own opinion, but I find the second approach cleaner and more reliable. Regarding the fact that it would require a specific parameter to be enabled, I already use several parameters on a systematic basis with Qemu (enable KVM, the USB tablet, set the keyboard layout, etc.). I don't see the fact of adding a supplementary one to this set as an annoyance. On the contrary, I love Qemu's versatility and all these parameters are here just to let users personalize Qemu behavior to best suit the way they use it. Regards, Simon.
diff -ru a/qemu-options.hx b/qemu-options.hx --- a/qemu-options.hx 2016-12-20 21:16:49.000000000 +0100 +++ b/qemu-options.hx 2017-03-18 14:17:35.759915414 +0100 @@ -3322,6 +3322,19 @@ disk image. ETEXI +DEF("powerdown", 0, QEMU_OPTION_powerdown, \ + "-powerdown Cleanly power down the guest on SIGINT or SIGHUP\n", \ + QEMU_ARCH_ALL) +STEXI +@item -powerdown +@findex -powerdown +Don't forcefully shutdown the guest upon SIGINT (Ctrl-C) or SIGHUP (terminal +closure) signals, but instead attempt to cleanly stop them using an ACPI +shutdown request. +Non ACPI-aware and stuck guests will remain up, the SIGTERM signal will still +forcefully shutdown them. +ETEXI + DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \ "-loadvm [tag|id]\n" \ " start right away with a saved state (loadvm in monitor)\n", diff -ru a/vl.c b/vl.c --- a/vl.c 2016-12-20 21:16:54.000000000 +0100 +++ b/vl.c 2017-03-18 13:48:21.227967255 +0100 @@ -164,6 +164,7 @@ int fd_bootchk = 1; static int no_reboot; int no_shutdown = 0; +int powerdown = 0; int cursor_hide = 1; int graphic_rotate = 0; const char *watchdog; @@ -1871,7 +1872,11 @@ /* Cannot call qemu_system_shutdown_request directly because * we are in a signal handler. */ - shutdown_requested = 1; + if (powerdown == 1 && (signal == SIGINT || signal == SIGHUP)) { + powerdown_requested = 1; + } else { + shutdown_requested = 1; + } qemu_notify_event(); } @@ -3794,6 +3799,9 @@ case QEMU_OPTION_no_shutdown: no_shutdown = 1; break; + case QEMU_OPTION_powerdown: + powerdown = 1; + break; case QEMU_OPTION_show_cursor: cursor_hide = 0; break;
Hi, The patch below adds the new command-line option `-powerdown' which changes the behavior for both SIGHUP and SIGINT signals to cause a clean power down of the guest using an ACPI shutdown request. If this option is not used, the original behavior is kept. Regards, Simon. Signed-off-by: Simon Geusebroek <qemu.bugs@whitewinterwolf.com> --- --