[PATCH QEMU v9 0/9] migration: introduce dirtylimit capability

[~hyman]

Markus, thank Markus for crafting the comments
please review the latest version.

Yong

v7~v9:
Rebase on master, fix conflicts and craft the docs suggested by Markus

v6:
1. Rebase on master
2. Split the commit "Implement dirty-limit convergence algo" into two as
    Juan suggested as the following:
    a. Put the detection logic before auto-converge checking
    b. Implement dirty-limit convergence algo
3. Put the detection logic before auto-converge checking
4. Sort the migrate_dirty_limit function in commit
    "Introduce dirty-limit capability" suggested by Juan
5. Substitute the the int64_t to uint64_t in the last 2 commits
6. Fix the comments spell mistake
7. Add helper function in the commit
    "Implement dirty-limit convergence algo" suggested by Juan

v5:
1. Rebase on master and enrich the comment for "dirty-limit" capability,
    suggesting by Markus.
2. Drop commits that have already been merged.

v4:
1. Polish the docs and update the release version suggested by Markus
2. Rename the migrate exported info "dirty-limit-throttle-time-per-
round"
   to "dirty-limit-throttle-time-per-full".

v3(resend):
- fix the syntax error of the topic.

v3:
This version make some modifications inspired by Peter and Markus
as following:
1. Do the code clean up in [PATCH v2 02/11] suggested by Markus
2. Replace the [PATCH v2 03/11] with a much simpler patch posted by
   Peter to fix the following bug:
   https://bugzilla.redhat.com/show_bug.cgi?id=2124756
3. Fix the error path of migrate_params_check in [PATCH v2 04/11]
   pointed out by Markus. Enrich the commit message to explain why
   x-vcpu-dirty-limit-period an unstable parameter.
4. Refactor the dirty-limit convergence algo in [PATCH v2 07/11]
   suggested by Peter:
   a. apply blk_mig_bulk_active check before enable dirty-limit
   b. drop the unhelpful check function before enable dirty-limit
   c. change the migration_cancel logic, just cancel dirty-limit
      only if dirty-limit capability turned on.
   d. abstract a code clean commit [PATCH v3 07/10] to adjust
      the check order before enable auto-converge
5. Change the name of observing indexes during dirty-limit live
   migration to make them more easy-understanding. Use the
   maximum throttle time of vpus as "dirty-limit-throttle-time-per-full"
6. Fix some grammatical and spelling errors pointed out by Markus
   and enrich the document about the dirty-limit live migration
   observing indexes "dirty-limit-ring-full-time"
   and "dirty-limit-throttle-time-per-full"
7. Change the default value of x-vcpu-dirty-limit-period to 1000ms,
   which is optimal value pointed out in cover letter in that
   testing environment.
8. Drop the 2 guestperf test commits [PATCH v2 10/11],
   [PATCH v2 11/11] and post them with a standalone series in the
   future.

v2:
This version make a little bit modifications comparing with
version 1 as following:
1. fix the overflow issue reported by Peter Maydell
2. add parameter check for hmp "set_vcpu_dirty_limit" command
3. fix the racing issue between dirty ring reaper thread and
   Qemu main thread.
4. add migrate parameter check for x-vcpu-dirty-limit-period
   and vcpu-dirty-limit.
5. add the logic to forbid hmp/qmp commands set_vcpu_dirty_limit,
   cancel_vcpu_dirty_limit during dirty-limit live migration when
   implement dirty-limit convergence algo.
6. add capability check to ensure auto-converge and dirty-limit
   are mutually exclusive.
7. pre-check if kvm dirty ring size is configured before setting
   dirty-limit migrate parameter

Hyman Huang(黄勇) (9):
  softmmu/dirtylimit: Add parameter check for hmp "set_vcpu_dirty_limit"
  qapi/migration: Introduce x-vcpu-dirty-limit-period parameter
  qapi/migration: Introduce vcpu-dirty-limit parameters
  migration: Introduce dirty-limit capability
  migration: Refactor auto-converge capability logic
  migration: Put the detection logic before auto-converge checking
  migration: Implement dirty-limit convergence algorithm
  migration: Extend query-migrate to provide dirty-limit info
  tests: Add migration dirty-limit capability test

 include/sysemu/dirtylimit.h    |   2 +
 migration/migration-hmp-cmds.c |  26 ++++++
 migration/migration.c          |  13 +++
 migration/options.c            |  73 ++++++++++++++++
 migration/options.h            |   1 +
 migration/ram.c                |  61 ++++++++++---
 migration/trace-events         |   1 +
 qapi/migration.json            |  72 +++++++++++++--
 softmmu/dirtylimit.c           |  91 +++++++++++++++++--
 tests/qtest/migration-test.c   | 155 +++++++++++++++++++++++++++++++++
 10 files changed, 470 insertions(+), 25 deletions(-)

-- 
2.38.5