Commit aedbe192 authored by Eric Blake's avatar Eric Blake Committed by Markus Armbruster
Browse files

shutdown: Prepare for use of an enum in reset/shutdown_request 



We want to track why a guest was shutdown; in particular, being able
to tell the difference between a guest request (such as ACPI request)
and host request (such as SIGINT) will prove useful to libvirt.
Since all requests eventually end up changing shutdown_requested in
vl.c, the logical change is to make that value track the reason,
rather than its current 0/1 contents.

Since command-line options control whether a reset request is turned
into a shutdown request instead, the same treatment is given to
reset_requested.

This patch adds an internal enum ShutdownCause that describes reasons
that a shutdown can be requested, and changes qemu_system_reset() to
pass the reason through, although for now nothing is actually changed
with regards to what gets reported.  The enum could be exported via
QAPI at a later date, if deemed necessary, but for now, there has not
been a request to expose that much detail to end clients.

For the most part, we turn 0 into SHUTDOWN_CAUSE_NONE, and 1 into
SHUTDOWN_CAUSE_HOST_ERROR; the only specific case where we have enough
information right now to use a different value is when we are reacting
to a host signal.  It will take a further patch to edit all call-sites
that can trigger a reset or shutdown request to properly pass in any
other reasons; this patch includes TODOs to point such places out.

qemu_system_reset() trades its 'bool report' parameter for a
'ShutdownCause reason', with all non-zero values having the same
effect; this lets us get rid of the weird #defines for VMRESET_*
as synonyms for bools.

Signed-off-by: default avatarEric Blake <eblake@redhat.com>
Message-Id: <20170515214114.15442-3-eblake@redhat.com>
Reviewed-by: default avatarMarkus Armbruster <armbru@redhat.com>
Signed-off-by: default avatarMarkus Armbruster <armbru@redhat.com>
parent 7af88279

hw/i386/xen/xen-hvm.c

+5 −2
Original line number Diff line number Diff line
@@ -1089,11 +1089,14 @@ static void cpu_handle_ioreq(void *opaque) 
         * causes Xen to powerdown the domain.

         */

        if (runstate_is_running()) {

            ShutdownCause request;



            if (qemu_shutdown_requested_get()) {

                destroy_hvm_domain(false);

            }

            if (qemu_reset_requested_get()) {

                qemu_system_reset(VMRESET_REPORT);

            request = qemu_reset_requested_get();

            if (request) {

                qemu_system_reset(request);

                destroy_hvm_domain(true);

            }

        }

include/sysemu/sysemu.h

+18 −5
Original line number Diff line number Diff line
@@ -33,8 +33,21 @@ VMChangeStateEntry *qemu_add_vm_change_state_handler(VMChangeStateHandler *cb, 
void qemu_del_vm_change_state_handler(VMChangeStateEntry *e);

void vm_state_notify(int running, RunState state);



#define VMRESET_SILENT   false

#define VMRESET_REPORT   true

/* Enumeration of various causes for shutdown. */

typedef enum ShutdownCause {

    SHUTDOWN_CAUSE_NONE,          /* No shutdown request pending */

    SHUTDOWN_CAUSE_HOST_ERROR,    /* An error prevents further use of guest */

    SHUTDOWN_CAUSE_HOST_QMP,      /* Reaction to a QMP command, like 'quit' */

    SHUTDOWN_CAUSE_HOST_SIGNAL,   /* Reaction to a signal, such as SIGINT */

    SHUTDOWN_CAUSE_HOST_UI,       /* Reaction to UI event, like window close */

    SHUTDOWN_CAUSE_GUEST_SHUTDOWN,/* Guest shutdown/suspend request, via

                                     ACPI or other hardware-specific means */

    SHUTDOWN_CAUSE_GUEST_RESET,   /* Guest reset request, and command line

                                     turns that into a shutdown */

    SHUTDOWN_CAUSE_GUEST_PANIC,   /* Guest panicked, and command line turns

                                     that into a shutdown */

    SHUTDOWN_CAUSE__MAX,

} ShutdownCause;



void vm_start(void);

int vm_prepare_start(void);
@@ -62,10 +75,10 @@ void qemu_system_debug_request(void); 
void qemu_system_vmstop_request(RunState reason);

void qemu_system_vmstop_request_prepare(void);

bool qemu_vmstop_requested(RunState *r);

int qemu_shutdown_requested_get(void);

int qemu_reset_requested_get(void);

ShutdownCause qemu_shutdown_requested_get(void);

ShutdownCause qemu_reset_requested_get(void);

void qemu_system_killed(int signal, pid_t pid);

void qemu_system_reset(bool report);

void qemu_system_reset(ShutdownCause reason);

void qemu_system_guest_panicked(GuestPanicInformation *info);

size_t qemu_target_page_size(void);

migration/colo.c

+1 −1
Original line number Diff line number Diff line
@@ -623,7 +623,7 @@ void *colo_process_incoming_thread(void *opaque) 
        }



        qemu_mutex_lock_iothread();

        qemu_system_reset(VMRESET_SILENT);

        qemu_system_reset(SHUTDOWN_CAUSE_NONE);

        vmstate_loading = true;

        if (qemu_loadvm_state(fb) < 0) {

            error_report("COLO: loadvm failed");

migration/savevm.c

+1 −1
Original line number Diff line number Diff line
@@ -2285,7 +2285,7 @@ int load_vmstate(const char *name, Error **errp) 
        return -EINVAL;

    }



    qemu_system_reset(VMRESET_SILENT);

    qemu_system_reset(SHUTDOWN_CAUSE_NONE);

    mis->from_src_file = f;



    aio_context_acquire(aio_context);

vl.c

+33 −20
Original line number Diff line number Diff line
@@ -1597,8 +1597,9 @@ void vm_state_notify(int running, RunState state) 
    }

}



static int reset_requested;

static int shutdown_requested, shutdown_signal;

static ShutdownCause reset_requested;

static ShutdownCause shutdown_requested;

static int shutdown_signal;

static pid_t shutdown_pid;

static int powerdown_requested;

static int debug_requested;
@@ -1612,19 +1613,19 @@ static NotifierList wakeup_notifiers = 
    NOTIFIER_LIST_INITIALIZER(wakeup_notifiers);

static uint32_t wakeup_reason_mask = ~(1 << QEMU_WAKEUP_REASON_NONE);



int qemu_shutdown_requested_get(void)

ShutdownCause qemu_shutdown_requested_get(void)

{

    return shutdown_requested;

}



int qemu_reset_requested_get(void)

ShutdownCause qemu_reset_requested_get(void)

{

    return reset_requested;

}



static int qemu_shutdown_requested(void)

{

    return atomic_xchg(&shutdown_requested, 0);

    return atomic_xchg(&shutdown_requested, SHUTDOWN_CAUSE_NONE);

}



static void qemu_kill_report(void)
@@ -1647,14 +1648,15 @@ static void qemu_kill_report(void) 
    }

}



static int qemu_reset_requested(void)

static ShutdownCause qemu_reset_requested(void)

{

    int r = reset_requested;

    ShutdownCause r = reset_requested;



    if (r && replay_checkpoint(CHECKPOINT_RESET_REQUESTED)) {

        reset_requested = 0;

        reset_requested = SHUTDOWN_CAUSE_NONE;

        return r;

    }

    return false;

    return SHUTDOWN_CAUSE_NONE;

}



static int qemu_suspend_requested(void)
@@ -1686,7 +1688,10 @@ static int qemu_debug_requested(void) 
    return r;

}



void qemu_system_reset(bool report)

/*

 * Reset the VM. Issue an event unless @reason is SHUTDOWN_CAUSE_NONE.

 */

void qemu_system_reset(ShutdownCause reason)

{

    MachineClass *mc;
@@ -1699,7 +1704,8 @@ void qemu_system_reset(bool report) 
    } else {

        qemu_devices_reset();

    }

    if (report) {

    if (reason) {

        /* TODO update event based on reason */

        qapi_event_send_reset(&error_abort);

    }

    cpu_synchronize_all_post_reset();
@@ -1738,9 +1744,10 @@ void qemu_system_guest_panicked(GuestPanicInformation *info) 
void qemu_system_reset_request(void)

{

    if (no_reboot) {

        shutdown_requested = 1;

        /* TODO - add a parameter to allow callers to specify reason */

        shutdown_requested = SHUTDOWN_CAUSE_HOST_ERROR;

    } else {

        reset_requested = 1;

        reset_requested = SHUTDOWN_CAUSE_HOST_ERROR;

    }

    cpu_stop_current();

    qemu_notify_event();
@@ -1807,7 +1814,7 @@ void qemu_system_killed(int signal, pid_t pid) 
    /* Cannot call qemu_system_shutdown_request directly because

     * we are in a signal handler.

     */

    shutdown_requested = 1;

    shutdown_requested = SHUTDOWN_CAUSE_HOST_SIGNAL;

    qemu_notify_event();

}
@@ -1815,7 +1822,8 @@ void qemu_system_shutdown_request(void) 
{

    trace_qemu_system_shutdown_request();

    replay_shutdown_request();

    shutdown_requested = 1;

    /* TODO - add a parameter to allow callers to specify reason */

    shutdown_requested = SHUTDOWN_CAUSE_HOST_ERROR;

    qemu_notify_event();

}
@@ -1846,14 +1854,18 @@ void qemu_system_debug_request(void) 
static bool main_loop_should_exit(void)

{

    RunState r;

    ShutdownCause request;



    if (qemu_debug_requested()) {

        vm_stop(RUN_STATE_DEBUG);

    }

    if (qemu_suspend_requested()) {

        qemu_system_suspend();

    }

    if (qemu_shutdown_requested()) {

    request = qemu_shutdown_requested();

    if (request) {

        qemu_kill_report();

        /* TODO update event based on request */

        qapi_event_send_shutdown(&error_abort);

        if (no_shutdown) {

            vm_stop(RUN_STATE_SHUTDOWN);
@@ -1861,9 +1873,10 @@ static bool main_loop_should_exit(void) 
            return true;

        }

    }

    if (qemu_reset_requested()) {

    request = qemu_reset_requested();

    if (request) {

        pause_all_vcpus();

        qemu_system_reset(VMRESET_REPORT);

        qemu_system_reset(request);

        resume_all_vcpus();

        if (!runstate_check(RUN_STATE_RUNNING) &&

                !runstate_check(RUN_STATE_INMIGRATE)) {
@@ -1872,7 +1885,7 @@ static bool main_loop_should_exit(void) 
    }

    if (qemu_wakeup_requested()) {

        pause_all_vcpus();

        qemu_system_reset(VMRESET_SILENT);

        qemu_system_reset(SHUTDOWN_CAUSE_NONE);

        notifier_list_notify(&wakeup_notifiers, &wakeup_reason);

        wakeup_reason = QEMU_WAKEUP_REASON_NONE;

        resume_all_vcpus();
@@ -4696,7 +4709,7 @@ int main(int argc, char **argv, char **envp) 
       reading from the other reads, because timer polling functions query

       clock values from the log. */

    replay_checkpoint(CHECKPOINT_RESET);

    qemu_system_reset(VMRESET_SILENT);

    qemu_system_reset(SHUTDOWN_CAUSE_NONE);

    register_global_state();

    if (replay_mode != REPLAY_MODE_NONE) {

        replay_vmstate_init();