From 802f045a5f61b781df55e4492d896b4d20503ba7 Mon Sep 17 00:00:00 2001 From: Eric Blake Date: Mon, 15 May 2017 16:41:12 -0500 Subject: [PATCH] shutdown: Preserve shutdown cause through replay With the recent addition of ShutdownCause, we want to be able to pass a cause through any shutdown request, and then faithfully replay that cause when later replaying the same sequence. The easiest way is to expand the reply event mechanism to track a series of values for EVENT_SHUTDOWN, one corresponding to each value of ShutdownCause. We are free to change the replay stream as needed, since there are already no guarantees about being able to use a replay stream by any other version of qemu than the one that generated it. The cause is not actually fed back until the next patch changes the signature for requesting a shutdown; a TODO marks that upcoming change. Yes, this uses the gcc/clang extension of a ranged case label, but this is not the first time we've used non-C99 constructs. Signed-off-by: Eric Blake Reviewed-by: Pavel Dovgalyuk Message-Id: <20170515214114.15442-4-eblake@redhat.com> Reviewed-by: Markus Armbruster Signed-off-by: Markus Armbruster --- include/sysemu/replay.h | 3 ++- replay/replay-internal.h | 3 ++- replay/replay.c | 7 ++++--- vl.c | 2 +- 4 files changed, 9 insertions(+), 6 deletions(-) diff --git a/include/sysemu/replay.h b/include/sysemu/replay.h index f1c0712795dc..fa14d0ec0b29 100644 --- a/include/sysemu/replay.h +++ b/include/sysemu/replay.h @@ -13,6 +13,7 @@ */ #include "qapi-types.h" +#include "sysemu.h" /* replay clock kinds */ enum ReplayClockKind { @@ -98,7 +99,7 @@ int64_t replay_read_clock(ReplayClockKind kind); /* Events */ /*! Called when qemu shutdown is requested. */ -void replay_shutdown_request(void); +void replay_shutdown_request(ShutdownCause cause); /*! Should be called at check points in the execution. These check points are skipped, if they were not met. Saves checkpoint in the SAVE mode and validates in the PLAY mode. diff --git a/replay/replay-internal.h b/replay/replay-internal.h index ed66ed803ce4..3ebb19912a78 100644 --- a/replay/replay-internal.h +++ b/replay/replay-internal.h @@ -22,8 +22,9 @@ enum ReplayEvents { EVENT_EXCEPTION, /* for async events */ EVENT_ASYNC, - /* for shutdown request */ + /* for shutdown requests, range allows recovery of ShutdownCause */ EVENT_SHUTDOWN, + EVENT_SHUTDOWN_LAST = EVENT_SHUTDOWN + SHUTDOWN_CAUSE__MAX, /* for character device write event */ EVENT_CHAR_WRITE, /* for character device read all event */ diff --git a/replay/replay.c b/replay/replay.c index f810628cac52..bf94e812611d 100644 --- a/replay/replay.c +++ b/replay/replay.c @@ -49,8 +49,9 @@ bool replay_next_event_is(int event) res = true; } switch (replay_state.data_kind) { - case EVENT_SHUTDOWN: + case EVENT_SHUTDOWN ... EVENT_SHUTDOWN_LAST: replay_finish_event(); + /* TODO - pass replay_state.data_kind - EVENT_SHUTDOWN as cause */ qemu_system_shutdown_request(); break; default: @@ -170,11 +171,11 @@ bool replay_has_interrupt(void) return res; } -void replay_shutdown_request(void) +void replay_shutdown_request(ShutdownCause cause) { if (replay_mode == REPLAY_MODE_RECORD) { replay_mutex_lock(); - replay_put_event(EVENT_SHUTDOWN); + replay_put_event(EVENT_SHUTDOWN + cause); replay_mutex_unlock(); } } diff --git a/vl.c b/vl.c index d90ae3f20a3b..909519ff8399 100644 --- a/vl.c +++ b/vl.c @@ -1821,8 +1821,8 @@ void qemu_system_killed(int signal, pid_t pid) void qemu_system_shutdown_request(void) { trace_qemu_system_shutdown_request(); - replay_shutdown_request(); /* TODO - add a parameter to allow callers to specify reason */ + replay_shutdown_request(SHUTDOWN_CAUSE_HOST_ERROR); shutdown_requested = SHUTDOWN_CAUSE_HOST_ERROR; qemu_notify_event(); }