From 39ba2ea61f510512764e6f9063a8396d05fe57fe Mon Sep 17 00:00:00 2001 From: Peter Xu Date: Thu, 18 Feb 2016 13:16:54 +0800 Subject: Dump: add qmp command "query-dump" When dump-guest-memory is requested with detach flag, after its return, user could query its status using "query-dump" command (with no argument). The result contains: - status: current dump status - completed: bytes written in the latest dump - total: bytes to write in the latest dump From completed and total, we could know how much work finished by calculating: 100.0 * completed / total (%) Reviewed-by: Fam Zheng Signed-off-by: Peter Xu Message-Id: <1455772616-8668-10-git-send-email-peterx@redhat.com> Signed-off-by: Paolo Bonzini --- dump.c | 23 +++++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-) (limited to 'dump.c') diff --git a/dump.c b/dump.c index cd4ae5e9e6..9dc494619d 100644 --- a/dump.c +++ b/dump.c @@ -1456,7 +1456,7 @@ static void dump_state_prepare(DumpState *s) bool dump_in_progress(void) { DumpState *state = &dump_state_global; - return (state->status == DUMP_STATUS_ACTIVE); + return (atomic_read(&state->status) == DUMP_STATUS_ACTIVE); } /* calculate total size of memory to be dumped (taking filter into @@ -1669,9 +1669,12 @@ static void dump_process(DumpState *s, Error **errp) create_vmcore(s, &local_err); } - s->status = (local_err ? DUMP_STATUS_FAILED : DUMP_STATUS_COMPLETED); - error_propagate(errp, local_err); + /* make sure status is written after written_size updates */ + smp_wmb(); + atomic_set(&s->status, + (local_err ? DUMP_STATUS_FAILED : DUMP_STATUS_COMPLETED)); + error_propagate(errp, local_err); dump_cleanup(s); } @@ -1689,6 +1692,18 @@ static void *dump_thread(void *data) return NULL; } +DumpQueryResult *qmp_query_dump(Error **errp) +{ + DumpQueryResult *result = g_new(DumpQueryResult, 1); + DumpState *state = &dump_state_global; + result->status = atomic_read(&state->status); + /* make sure we are reading status and written_size in order */ + smp_rmb(); + result->completed = state->written_size; + result->total = state->total_size; + return result; +} + void qmp_dump_guest_memory(bool paging, const char *file, bool has_detach, bool detach, bool has_begin, int64_t begin, bool has_length, @@ -1779,7 +1794,7 @@ void qmp_dump_guest_memory(bool paging, const char *file, begin, length, &local_err); if (local_err) { error_propagate(errp, local_err); - s->status = DUMP_STATUS_FAILED; + atomic_set(&s->status, DUMP_STATUS_FAILED); return; } -- cgit v1.2.3