[Qemu-devel] [PATCH v4 03/11] dump-guest-memory: using static DumpState, add DumpStatus

[Peter Xu <peterx@redhat.com>]

Instead of malloc/free each time for DumpState, make it
static. Added DumpStatus to show status for dump.

This is to be used for detached dump.

Signed-off-by: Peter Xu <peterx@redhat.com>
---
 dump.c                | 20 +++++++++++++++++---
 include/sysemu/dump.h |  2 ++
 qapi-schema.json      | 18 ++++++++++++++++++
 3 files changed, 37 insertions(+), 3 deletions(-)

diff --git a/dump.c b/dump.c
index d79e0ed..f5f3c59 100644
--- a/dump.c
+++ b/dump.c
@@ -1418,6 +1418,14 @@ static void get_max_mapnr(DumpState *s)
     s->max_mapnr = paddr_to_pfn(last_block->target_end);
 }
 
+static DumpState dump_state_global = { .status = DUMP_STATUS_NONE };
+
+static void dump_state_prepare(DumpState *s)
+{
+    /* zero the struct, setting status to active */
+    *s = (DumpState) { .status = DUMP_STATUS_ACTIVE };
+}
+
 static void dump_init(DumpState *s, int fd, bool has_format,
                       DumpGuestMemoryFormat format, bool paging, bool has_filter,
                       int64_t begin, int64_t length, Error **errp)
@@ -1647,13 +1655,14 @@ void qmp_dump_guest_memory(bool paging, const char *file,
         return;
     }
 
-    s = g_malloc0(sizeof(DumpState));
+    s = &dump_state_global;
+    dump_state_prepare(s);
 
     dump_init(s, fd, has_format, format, paging, has_begin,
               begin, length, &local_err);
     if (local_err) {
-        g_free(s);
         error_propagate(errp, local_err);
+        s->status = DUMP_STATUS_FAILED;
         return;
     }
 
@@ -1663,8 +1672,13 @@ void qmp_dump_guest_memory(bool paging, const char *file,
         create_vmcore(s, errp);
     }
 
+    if (*errp) {
+        s->status = DUMP_STATUS_FAILED;
+    } else {
+        s->status = DUMP_STATUS_COMPLETED;
+    }
+
     dump_cleanup(s);
-    g_free(s);
 }
 
 DumpGuestMemoryCapability *qmp_query_dump_guest_memory_capability(Error **errp)
diff --git a/include/sysemu/dump.h b/include/sysemu/dump.h
index 7e4ec5c..affef38 100644
--- a/include/sysemu/dump.h
+++ b/include/sysemu/dump.h
@@ -45,6 +45,7 @@
 
 #include "sysemu/dump-arch.h"
 #include "sysemu/memory_mapping.h"
+#include "qapi-types.h"
 
 typedef struct QEMU_PACKED MakedumpfileHeader {
     char signature[16];     /* = "makedumpfile" */
@@ -183,6 +184,7 @@ typedef struct DumpState {
     off_t offset_page;          /* offset of page part in vmcore */
     size_t num_dumpable;        /* number of page that can be dumped */
     uint32_t flag_compress;     /* indicate the compression format */
+    DumpStatus status;          /* current dump status */
 } DumpState;
 
 uint16_t cpu_to_dump16(DumpState *s, uint16_t val);
diff --git a/qapi-schema.json b/qapi-schema.json
index 97c3ac4..691a130 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -2139,6 +2139,24 @@
             '*format': 'DumpGuestMemoryFormat'} }
 
 ##
+# @DumpStatus
+#
+# Describe the status of a long-running background guest memory dump.
+#
+# @none: no dump-guest-memory has started yet.
+#
+# @active: there is one dump running in background.
+#
+# @completed: the last dump has finished successfully.
+#
+# @failed: the last dump has failed.
+#
+# Since 2.6
+##
+{ 'enum': 'DumpStatus',
+  'data': [ 'none', 'active', 'completed', 'failed' ] }
+
+##
 # @DumpGuestMemoryCapability:
 #
 # A list of the available formats for dump-guest-memory
-- 
2.4.3