Re: [PATCH RESEND v6 02/36] multi-process: Refactor machine_init and exit notifiers

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

On 4/23/20 6:13 AM, elena.ufimtseva@oracle.com wrote:
> From: Elena Ufimtseva <elena.ufimtseva@oracle.com>
> 
> Relocate machine_int and exit notifiers into common code
> 
> Signed-off-by: Elena Ufimtseva <elena.ufimtseva@oracle.com>
> Signed-off-by: John G Johnson <john.g.johnson@oracle.com>
> Signed-off-by: Jagannathan Raman <jag.raman@oracle.com>
> ---
>   MAINTAINERS                 |  1 +
>   Makefile.objs               |  1 +
>   include/sysemu/sysemu.h     |  2 ++
>   softmmu/vl.c                | 42 ----------------------
>   stubs/Makefile.objs         |  2 ++
>   stubs/machine-init-add.c    |  7 ++++
>   stubs/machine-init-done.c   |  5 ++-
>   stubs/machine-init-remove.c |  8 +++++
>   util/machine-notify.c       | 69 +++++++++++++++++++++++++++++++++++++
>   9 files changed, 92 insertions(+), 45 deletions(-)
>   create mode 100644 stubs/machine-init-add.c
>   create mode 100644 stubs/machine-init-remove.c
>   create mode 100644 util/machine-notify.c
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 8cbc1fac2b..04b19ac56c 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -2133,6 +2133,7 @@ F: util/qemu-timer.c
>   F: softmmu/vl.c
>   F: softmmu/main.c
>   F: qapi/run-state.json
> +F: util/machine-notify.c
>   
>   Human Monitor (HMP)
>   M: Dr. David Alan Gilbert <dgilbert@redhat.com>
> diff --git a/Makefile.objs b/Makefile.objs
> index a7c967633a..bfb9271862 100644
> --- a/Makefile.objs
> +++ b/Makefile.objs
> @@ -79,6 +79,7 @@ qemu-seccomp.o-libs := $(SECCOMP_LIBS)
>   common-obj-$(CONFIG_FDT) += device_tree.o
>   
>   common-obj-y += qapi/
> +common-obj-y += util/machine-notify.o
>   
>   endif # CONFIG_SOFTMMU
>   
> diff --git a/include/sysemu/sysemu.h b/include/sysemu/sysemu.h
> index ef81302e1a..2438dd7bea 100644
> --- a/include/sysemu/sysemu.h
> +++ b/include/sysemu/sysemu.h
> @@ -17,11 +17,13 @@ extern bool qemu_uuid_set;
>   
>   void qemu_add_exit_notifier(Notifier *notify);
>   void qemu_remove_exit_notifier(Notifier *notify);
> +void qemu_run_exit_notifiers(void);
>   
>   extern bool machine_init_done;
>   
>   void qemu_add_machine_init_done_notifier(Notifier *notify);
>   void qemu_remove_machine_init_done_notifier(Notifier *notify);
> +void qemu_run_machine_init_done_notifiers(void);
>   
>   extern int autostart;
>   
> diff --git a/softmmu/vl.c b/softmmu/vl.c
> index 32c0047889..39cbb6b50d 100644
> --- a/softmmu/vl.c
> +++ b/softmmu/vl.c
> @@ -172,12 +172,6 @@ int icount_align_option;
>   QemuUUID qemu_uuid;
>   bool qemu_uuid_set;
>   
> -static NotifierList exit_notifiers =
> -    NOTIFIER_LIST_INITIALIZER(exit_notifiers);
> -
> -static NotifierList machine_init_done_notifiers =
> -    NOTIFIER_LIST_INITIALIZER(machine_init_done_notifiers);
> -
>   bool xen_allowed;
>   uint32_t xen_domid;
>   enum xen_mode xen_mode = XEN_EMULATE;
> @@ -2325,21 +2319,6 @@ static MachineClass *machine_parse(const char *name, GSList *machines)
>       return mc;
>   }
>   
> -void qemu_add_exit_notifier(Notifier *notify)
> -{
> -    notifier_list_add(&exit_notifiers, notify);
> -}
> -
> -void qemu_remove_exit_notifier(Notifier *notify)
> -{
> -    notifier_remove(notify);
> -}
> -
> -static void qemu_run_exit_notifiers(void)
> -{
> -    notifier_list_notify(&exit_notifiers, NULL);
> -}
> -
>   static const char *pid_file;
>   static Notifier qemu_unlink_pidfile_notifier;
>   
> @@ -2350,27 +2329,6 @@ static void qemu_unlink_pidfile(Notifier *n, void *data)
>       }
>   }
>   
> -bool machine_init_done;
> -
> -void qemu_add_machine_init_done_notifier(Notifier *notify)
> -{
> -    notifier_list_add(&machine_init_done_notifiers, notify);
> -    if (machine_init_done) {
> -        notify->notify(notify, NULL);
> -    }
> -}
> -
> -void qemu_remove_machine_init_done_notifier(Notifier *notify)
> -{
> -    notifier_remove(notify);
> -}
> -
> -static void qemu_run_machine_init_done_notifiers(void)
> -{
> -    machine_init_done = true;
> -    notifier_list_notify(&machine_init_done_notifiers, NULL);
> -}
> -
>   static const QEMUOption *lookup_opt(int argc, char **argv,
>                                       const char **poptarg, int *poptind)
>   {
> diff --git a/stubs/Makefile.objs b/stubs/Makefile.objs
> index 45be5dc0ed..f884bb6180 100644
> --- a/stubs/Makefile.objs
> +++ b/stubs/Makefile.objs
> @@ -43,4 +43,6 @@ stub-obj-y += pci-host-piix.o
>   stub-obj-y += ram-block.o
>   stub-obj-y += ramfb.o
>   stub-obj-y += fw_cfg.o
> +stub-obj-y += machine-init-add.o
> +stub-obj-y += machine-init-remove.o

Trying to understand why we have this stub here...

So per commit 07a32d6b962 it is required by the chardev driver.

Marc-André, what do you think about extracting chardev_machine_*() to 
chardev/char-sysemu.c and simply add to chardev/Makefile:

chardev-obj-$(CONFIG_SOFTMMU) += char-sysemu.o


>   stub-obj-$(CONFIG_SOFTMMU) += semihost.o
> diff --git a/stubs/machine-init-add.c b/stubs/machine-init-add.c
> new file mode 100644
> index 0000000000..520dcb9801
> --- /dev/null
> +++ b/stubs/machine-init-add.c
> @@ -0,0 +1,7 @@
> +#include "qemu/osdep.h"
> +#include "sysemu/sysemu.h"
> +
> +void qemu_add_machine_init_done_notifier(Notifier *notify)
> +{
> +}
> +
> diff --git a/stubs/machine-init-done.c b/stubs/machine-init-done.c
> index cd8e81392d..a34d838f7a 100644
> --- a/stubs/machine-init-done.c
> +++ b/stubs/machine-init-done.c
> @@ -3,6 +3,5 @@
>   
>   bool machine_init_done = true;
>   
> -void qemu_add_machine_init_done_notifier(Notifier *notify)
> -{
> -}
> +NotifierList machine_init_done_notifiers =
> +    NOTIFIER_LIST_INITIALIZER(machine_init_done_notifiers);
> diff --git a/stubs/machine-init-remove.c b/stubs/machine-init-remove.c
> new file mode 100644
> index 0000000000..30aee27c2d
> --- /dev/null
> +++ b/stubs/machine-init-remove.c
> @@ -0,0 +1,8 @@
> +#include "qemu/osdep.h"
> +#include "sysemu/sysemu.h"
> +
> +void qemu_remove_machine_init_done_notifier(Notifier *notify)
> +{
> +}
> +
> +
> diff --git a/util/machine-notify.c b/util/machine-notify.c
> new file mode 100644
> index 0000000000..718af79335
> --- /dev/null
> +++ b/util/machine-notify.c
> @@ -0,0 +1,69 @@
> +/*
> + * Machine notifiers.
> + *
> + * Copyright (c) 2003-2008 Fabrice Bellard
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a copy
> + * of this software and associated documentation files (the "Software"), to deal
> + * in the Software without restriction, including without limitation the rights
> + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
> + * copies of the Software, and to permit persons to whom the Software is
> + * furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice shall be included in
> + * all copies or substantial portions of the Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
> + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
> + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
> + * THE SOFTWARE.
> + */
> +
> +#include "qemu/osdep.h"
> +#include "qemu/notify.h"
> +#include "sysemu/sysemu.h"
> +
> +static NotifierList machine_init_done_notifiers =
> +    NOTIFIER_LIST_INITIALIZER(machine_init_done_notifiers);
> +
> +static NotifierList exit_notifiers =
> +    NOTIFIER_LIST_INITIALIZER(exit_notifiers);
> +
> +bool machine_init_done;
> +
> +void qemu_add_machine_init_done_notifier(Notifier *notify)
> +{
> +    notifier_list_add(&machine_init_done_notifiers, notify);
> +    if (machine_init_done) {
> +        notify->notify(notify, NULL);
> +    }
> +}
> +
> +void qemu_remove_machine_init_done_notifier(Notifier *notify)
> +{
> +    notifier_remove(notify);
> +}
> +
> +void qemu_run_machine_init_done_notifiers(void)
> +{
> +    machine_init_done = true;
> +    notifier_list_notify(&machine_init_done_notifiers, NULL);
> +}
> +
> +void qemu_add_exit_notifier(Notifier *notify)
> +{
> +    notifier_list_add(&exit_notifiers, notify);
> +}
> +
> +void qemu_remove_exit_notifier(Notifier *notify)
> +{
> +    notifier_remove(notify);
> +}
> +
> +void qemu_run_exit_notifiers(void)
> +{
> +    notifier_list_notify(&exit_notifiers, NULL);
> +}
>