progressmeter: protect with a mutex

Progressmeter is protected by the AioContext mutex, which
is taken by the block jobs and their caller (like blockdev).

We would like to remove the dependency of block layer code on the
AioContext mutex, since most drivers and the core I/O code are already
not relying on it.

Create a new C file to implement the ProgressMeter API, but keep the
struct as public, to avoid forcing allocation on the heap.

Also add a mutex to be able to provide an accurate snapshot of the
progress values to the caller.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20210614081130.22134-5-eesposit@redhat.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>

1 files changed, 6 insertions, 2 deletions

diff --git a/job-qmp.c b/job-qmp.c
index 34c4da094f..829a28aa70 100644
--- a/job-qmp.c
+++ b/job-qmp.c
@@ -144,16 +144,20 @@ void qmp_job_dismiss(const char *id, Error **errp)
 static JobInfo *job_query_single(Job *job, Error **errp)
 {
     JobInfo *info;
+    uint64_t progress_current;
+    uint64_t progress_total;
 
     assert(!job_is_internal(job));
+    progress_get_snapshot(&job->progress, &progress_current,
+                          &progress_total);
 
     info = g_new(JobInfo, 1);
     *info = (JobInfo) {
         .id                 = g_strdup(job->id),
         .type               = job_type(job),
         .status             = job->status,
-        .current_progress   = job->progress.current,
-        .total_progress     = job->progress.total,
+        .current_progress   = progress_current,
+        .total_progress     = progress_total,
         .has_error          = !!job->err,
         .error              = job->err ? \
                               g_strdup(error_get_pretty(job->err)) : NULL,