debian/patches/pve/0050-PVE-Add-sequential-job-transaction-support.patch

   1 From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
   2 From: Stefan Reiter <s.reiter@proxmox.com>
   3 Date: Thu, 20 Aug 2020 14:31:59 +0200
   4 Subject: [PATCH] PVE: Add sequential job transaction support
   5
   6 ---
   7  include/qemu/job.h | 12 ++++++++++++
   8  job.c              | 24 ++++++++++++++++++++++++
   9  2 files changed, 36 insertions(+)
  10
  11 diff --git a/include/qemu/job.h b/include/qemu/job.h
  12 index 32aabb1c60..f7a6a0926a 100644
  13 --- a/include/qemu/job.h
  14 +++ b/include/qemu/job.h
  15 @@ -280,6 +280,18 @@ typedef enum JobCreateFlags {
  16   */
  17  JobTxn *job_txn_new(void);
  18
  19 +/**
  20 + * Create a new transaction and set it to sequential mode, i.e. run all jobs
  21 + * one after the other instead of at the same time.
  22 + */
  23 +JobTxn *job_txn_new_seq(void);
  24 +
  25 +/**
  26 + * Helper method to start the first job in a sequential transaction to kick it
  27 + * off. Other jobs will be run after this one completes.
  28 + */
  29 +void job_txn_start_seq(JobTxn *txn);
  30 +
  31  /**
  32   * Release a reference that was previously acquired with job_txn_add_job or
  33   * job_txn_new. If it's the last reference to the object, it will be freed.
  34 diff --git a/job.c b/job.c
  35 index b8139c80a4..97ee97a192 100644
  36 --- a/job.c
  37 +++ b/job.c
  38 @@ -72,6 +72,8 @@ struct JobTxn {
  39
  40      /* Reference count */
  41      int refcnt;
  42 +
  43 +    bool sequential;
  44  };
  45
  46  /* Right now, this mutex is only needed to synchronize accesses to job->busy
  47 @@ -102,6 +104,25 @@ JobTxn *job_txn_new(void)
  48      return txn;
  49  }
  50
  51 +JobTxn *job_txn_new_seq(void)
  52 +{
  53 +    JobTxn *txn = job_txn_new();
  54 +    txn->sequential = true;
  55 +    return txn;
  56 +}
  57 +
  58 +void job_txn_start_seq(JobTxn *txn)
  59 +{
  60 +    assert(txn->sequential);
  61 +    assert(!txn->aborting);
  62 +
  63 +    Job *first = QLIST_FIRST(&txn->jobs);
  64 +    assert(first);
  65 +    assert(first->status == JOB_STATUS_CREATED);
  66 +
  67 +    job_start(first);
  68 +}
  69 +
  70  static void job_txn_ref(JobTxn *txn)
  71  {
  72      txn->refcnt++;
  73 @@ -841,6 +862,9 @@ static void job_completed_txn_success(Job *job)
  74       */
  75      QLIST_FOREACH(other_job, &txn->jobs, txn_list) {
  76          if (!job_is_completed(other_job)) {
  77 +            if (txn->sequential) {
  78 +                job_start(other_job);
  79 +            }
  80              return;
  81          }
  82          assert(other_job->ret == 0);