Re: [PATCH 04/11] job: add .cancel handler for the driver
21.01.2021 02:17, Eric Blake wrote:
On 11/18/20 12:04 PM, Vladimir Sementsov-Ogievskiy wrote:
To be used in mirror in the following commit to cancel in-flight io on
target to not waste the time.
Signed-off-by: Vladimir Sementsov-Ogievskiy
---
include/qemu/job.h | 5 +
job.c | 3 +++
2 files changed, 8 insertions(+)
diff --git a/include/qemu/job.h b/include/qemu/job.h
index 32aabb1c60..efc6fa7544 100644
--- a/include/qemu/job.h
+++ b/include/qemu/job.h
@@ -251,6 +251,11 @@ struct JobDriver {
*/
void (*clean)(Job *job);
+/**
+ * If the callback is not NULL, it will be invoked in job_cancel_async
+ */
+void (*cancel)(Job *job);
+
Does the call need to be re-entrant or even worry about being invoked
more than once on the same BDS? Or worded differently,
+++ b/job.c
@@ -712,6 +712,9 @@ static int job_finalize_single(Job *job)
static void job_cancel_async(Job *job, bool force)
{
+if (job->driver->cancel) {
+job->driver->cancel(job);
+}
if (job->user_paused) {
can job_cancel_async be reached more than once on the same BDS?
what do you mean by same BDS? On same job?
I don't think that job_cancel_async should be called several times during one
"cancel" operation. But if it is, it's still safe enough with only .cancel
implementation in [05], which just calls bdrv_cancel_in_flight() (which of course should
be safe to call several times).
/* Do not call job_enter here, the caller will handle it. */
if (job->driver->user_resume) {
--
Best regards,
Vladimir
Re: [PATCH 04/11] job: add .cancel handler for the driver
On 11/18/20 12:04 PM, Vladimir Sementsov-Ogievskiy wrote:
> To be used in mirror in the following commit to cancel in-flight io on
> target to not waste the time.
>
> Signed-off-by: Vladimir Sementsov-Ogievskiy
> ---
> include/qemu/job.h | 5 +
> job.c | 3 +++
> 2 files changed, 8 insertions(+)
>
> diff --git a/include/qemu/job.h b/include/qemu/job.h
> index 32aabb1c60..efc6fa7544 100644
> --- a/include/qemu/job.h
> +++ b/include/qemu/job.h
> @@ -251,6 +251,11 @@ struct JobDriver {
> */
> void (*clean)(Job *job);
>
> +/**
> + * If the callback is not NULL, it will be invoked in job_cancel_async
> + */
> +void (*cancel)(Job *job);
> +
Does the call need to be re-entrant or even worry about being invoked
more than once on the same BDS? Or worded differently,
> +++ b/job.c
> @@ -712,6 +712,9 @@ static int job_finalize_single(Job *job)
>
> static void job_cancel_async(Job *job, bool force)
> {
> +if (job->driver->cancel) {
> +job->driver->cancel(job);
> +}
> if (job->user_paused) {
can job_cancel_async be reached more than once on the same BDS?
> /* Do not call job_enter here, the caller will handle it. */
> if (job->driver->user_resume) {
>
--
Eric Blake, Principal Software Engineer
Red Hat, Inc. +1-919-301-3226
Virtualization: qemu.org | libvirt.org
[PATCH 04/11] job: add .cancel handler for the driver
To be used in mirror in the following commit to cancel in-flight io on
target to not waste the time.
Signed-off-by: Vladimir Sementsov-Ogievskiy
---
include/qemu/job.h | 5 +
job.c | 3 +++
2 files changed, 8 insertions(+)
diff --git a/include/qemu/job.h b/include/qemu/job.h
index 32aabb1c60..efc6fa7544 100644
--- a/include/qemu/job.h
+++ b/include/qemu/job.h
@@ -251,6 +251,11 @@ struct JobDriver {
*/
void (*clean)(Job *job);
+/**
+ * If the callback is not NULL, it will be invoked in job_cancel_async
+ */
+void (*cancel)(Job *job);
+
/** Called when the job is freed */
void (*free)(Job *job);
diff --git a/job.c b/job.c
index 8fecf38960..65012dbd03 100644
--- a/job.c
+++ b/job.c
@@ -712,6 +712,9 @@ static int job_finalize_single(Job *job)
static void job_cancel_async(Job *job, bool force)
{
+if (job->driver->cancel) {
+job->driver->cancel(job);
+}
if (job->user_paused) {
/* Do not call job_enter here, the caller will handle it. */
if (job->driver->user_resume) {
--
2.21.3
