commit a7b4f8fc09ec62d09a11cce72a886c453636c547
author Emanuele Giuseppe Esposito <eesposit@redhat.com> Mon Jun 14 10:11:29 2021 +0200
committer Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Fri Jun 25 14:24:24 2021 +0300
tree 31e3c2f571527d4852a71ea0e1f7e90ffea9d927
parent c02b83ed1ff62211f4c44855e0ca1656d5811688

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>

qemu-img.c

diff --git a/qemu-img.c b/qemu-img.c
index a599368..7956a89 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -900,6 +900,7 @@
 
 static void run_block_job(BlockJob *job, Error **errp)
 {
+    uint64_t progress_current, progress_total;
     AioContext *aio_context = blk_get_aio_context(job->blk);
     int ret = 0;
 
@@ -908,9 +909,11 @@
     do {
         float progress = 0.0f;
         aio_poll(aio_context, true);
-        if (job->job.progress.total) {
-            progress = (float)job->job.progress.current /
-                       job->job.progress.total * 100.f;
+
+        progress_get_snapshot(&job->job.progress, &progress_current,
+                              &progress_total);
+        if (progress_total) {
+            progress = (float)progress_current / progress_total * 100.f;
         }
         qemu_progress_print(progress, 0);
     } while (!job_is_ready(&job->job) && !job_is_completed(&job->job));