5b15e2ecaf
Notable changes:
* The only big change is the switch to using a custom QIOChannel for
savevm-async, because the previously used QEMUFileOps was dropped.
Changes to the current implementation:
* Switch to vector based methods as required for an IO channel. For
short reads the passed-in IO vector is stuffed with zeroes at the
end, just to be sure.
* For reading: The documentation in include/io/channel.h states that
at least one byte should be read, so also error out when whe are
at the very end instead of returning 0.
* For reading: Fix off-by-one error when request goes beyond end.
The wrong code piece was:
if ((pos + size) > maxlen) {
size = maxlen - pos - 1;
}
Previously, the last byte would not be read. It's actually
possible to get a snapshot .raw file that has content all the way
up the final 512 byte (= BDRV_SECTOR_SIZE) boundary without any
trailing zero bytes (I wrote a script to do it).
Luckily, it didn't cause a real issue, because qemu_loadvm_state()
is not interested in the final (i.e. QEMU_VM_VMDESCRIPTION)
section. The buffer for reading it is simply freed up afterwards
and the function will assume that it read the whole section, even
if that's not the case.
* For writing: Make use of the generated blk_pwritev() wrapper
instead of manually wrapping the coroutine to simplify and save a
few lines.
* Adapt to changed interfaces for blk_{pread,pwrite}:
* a9262f551e ("block: Change blk_{pread,pwrite}() param order")
* 3b35d4542c ("block: Add a 'flags' param to blk_pread()")
* bf5b16fa40 ("block: Make blk_{pread,pwrite}() return 0 on success")
Those changes especially affected the qemu-img dd patches, because
the context also changed, but also some of our block drivers used
the functions.
* Drop qemu-common.h include: it got renamed after essentially
everything was moved to other headers. The only remaining user I
could find for things dropped from the header between 7.0 and 7.1
was qemu_get_vm_name() in the iscsi-initiatorname patch, but it
already includes the header to which the function was moved.
Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
99 lines
2.8 KiB
Diff
99 lines
2.8 KiB
Diff
From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
|
|
From: Stefan Reiter <s.reiter@proxmox.com>
|
|
Date: Thu, 20 Aug 2020 14:31:59 +0200
|
|
Subject: [PATCH] PVE: Add sequential job transaction support
|
|
|
|
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
|
|
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
|
|
---
|
|
include/qemu/job.h | 12 ++++++++++++
|
|
job.c | 31 +++++++++++++++++++++++++++++++
|
|
2 files changed, 43 insertions(+)
|
|
|
|
diff --git a/include/qemu/job.h b/include/qemu/job.h
|
|
index c105b31076..5096679571 100644
|
|
--- a/include/qemu/job.h
|
|
+++ b/include/qemu/job.h
|
|
@@ -316,6 +316,18 @@ typedef enum JobCreateFlags {
|
|
*/
|
|
JobTxn *job_txn_new(void);
|
|
|
|
+/**
|
|
+ * Create a new transaction and set it to sequential mode, i.e. run all jobs
|
|
+ * one after the other instead of at the same time.
|
|
+ */
|
|
+JobTxn *job_txn_new_seq(void);
|
|
+
|
|
+/**
|
|
+ * Helper method to start the first job in a sequential transaction to kick it
|
|
+ * off. Other jobs will be run after this one completes.
|
|
+ */
|
|
+void job_txn_start_seq(JobTxn *txn);
|
|
+
|
|
/**
|
|
* Release a reference that was previously acquired with job_txn_add_job or
|
|
* job_txn_new. If it's the last reference to the object, it will be freed.
|
|
diff --git a/job.c b/job.c
|
|
index e5699ad200..34c9758349 100644
|
|
--- a/job.c
|
|
+++ b/job.c
|
|
@@ -72,6 +72,8 @@ struct JobTxn {
|
|
|
|
/* Reference count */
|
|
int refcnt;
|
|
+
|
|
+ bool sequential;
|
|
};
|
|
|
|
/* Right now, this mutex is only needed to synchronize accesses to job->busy
|
|
@@ -102,6 +104,25 @@ JobTxn *job_txn_new(void)
|
|
return txn;
|
|
}
|
|
|
|
+JobTxn *job_txn_new_seq(void)
|
|
+{
|
|
+ JobTxn *txn = job_txn_new();
|
|
+ txn->sequential = true;
|
|
+ return txn;
|
|
+}
|
|
+
|
|
+void job_txn_start_seq(JobTxn *txn)
|
|
+{
|
|
+ assert(txn->sequential);
|
|
+ assert(!txn->aborting);
|
|
+
|
|
+ Job *first = QLIST_FIRST(&txn->jobs);
|
|
+ assert(first);
|
|
+ assert(first->status == JOB_STATUS_CREATED);
|
|
+
|
|
+ job_start(first);
|
|
+}
|
|
+
|
|
static void job_txn_ref(JobTxn *txn)
|
|
{
|
|
txn->refcnt++;
|
|
@@ -897,6 +918,9 @@ static void job_completed_txn_success(Job *job)
|
|
*/
|
|
QLIST_FOREACH(other_job, &txn->jobs, txn_list) {
|
|
if (!job_is_completed(other_job)) {
|
|
+ if (txn->sequential) {
|
|
+ job_start(other_job);
|
|
+ }
|
|
return;
|
|
}
|
|
assert(other_job->ret == 0);
|
|
@@ -1093,6 +1117,13 @@ int job_finish_sync(Job *job, void (*finish)(Job *, Error **errp), Error **errp)
|
|
return -EBUSY;
|
|
}
|
|
|
|
+ /* in a sequential transaction jobs with status CREATED can appear at time
|
|
+ * of cancelling, these have not begun work so job_enter won't do anything,
|
|
+ * let's ensure they are marked as ABORTING if required */
|
|
+ if (job->status == JOB_STATUS_CREATED && job->txn->sequential) {
|
|
+ job_update_rc(job);
|
|
+ }
|
|
+
|
|
AIO_WAIT_WHILE(job->aio_context,
|
|
(job_enter(job), !job_is_completed(job)));
|
|
|