Re: [PATCH v5 3/3] cpus-common: implement dirty limit on vCPU

2021-11-25 Thread Markus Armbruster
Hyman Huang  writes:

> 在 2021/11/24 23:33, Markus Armbruster 写道:
>> huang...@chinatelecom.cn writes:
>> 
>>> From: Hyman Huang(黄勇) 
>>>
>>> Implement dirtyrate calculation periodically basing on
>>> dirty-ring and throttle vCPU until it reachs the quota
>>> dirtyrate given by user.
>>>
>>> Introduce qmp commands set-dirty-limit/cancel-dirty-limit to
>>> set/cancel dirty limit on vCPU.
>>>
>>> Signed-off-by: Hyman Huang(黄勇) 

[...]

>>> diff --git a/qapi/migration.json b/qapi/migration.json
>>> index bbfd48c..42b260e 100644
>>> --- a/qapi/migration.json
>>> +++ b/qapi/migration.json
>>> @@ -1850,6 +1850,49 @@
>>>   { 'command': 'query-dirty-rate', 'returns': 'DirtyRateInfo' }
>>> ##
>>> +# @set-dirty-limit:
>>> +#
>>> +# Set the upper limit of dirty page rate for the interested vCPU.
>> "for a vCPU"
>> 
>>> +#
>>> +# This command could be used to cap the vCPU memory load, which is also
>>> +# refered as "dirty page rate". Users can use set-dirty-limit 
>>> unconditionally,
>>> +# but if one want to know which vCPU is in high memory load and which vCPU
>>> +# should be limited, "calc-dirty-rate" with "dirty-ring" mode maybe an
>>> +# availiable method.
>> I think you should mention that the command fails unless dirty ring
>> is
>> enabled, and a pointer to its documentation.
>> 
> Emm, it seems that there's no documentation about dirty ring in qemu,
> should i metion the commit b4420f19 "KVM: Dirty ring support" for
> dirty-ring?

I think the best you can do then is something like 'Property
"dirty-ring-size" of accelerator object "kvm" must be set.'

[...]




Re: [PATCH v5 3/3] cpus-common: implement dirty limit on vCPU

2021-11-25 Thread Hyman Huang




在 2021/11/24 23:33, Markus Armbruster 写道:

huang...@chinatelecom.cn writes:


From: Hyman Huang(黄勇) 

Implement dirtyrate calculation periodically basing on
dirty-ring and throttle vCPU until it reachs the quota
dirtyrate given by user.

Introduce qmp commands set-dirty-limit/cancel-dirty-limit to
set/cancel dirty limit on vCPU.

Signed-off-by: Hyman Huang(黄勇) 
---
  cpus-common.c | 41 +
  include/hw/core/cpu.h |  9 +
  qapi/migration.json   | 43 +++
  softmmu/vl.c  |  1 +
  4 files changed, 94 insertions(+)

diff --git a/cpus-common.c b/cpus-common.c
index 6e73d3e..43b0078 100644
--- a/cpus-common.c
+++ b/cpus-common.c
@@ -23,6 +23,11 @@
  #include "hw/core/cpu.h"
  #include "sysemu/cpus.h"
  #include "qemu/lockable.h"
+#include "sysemu/dirtylimit.h"
+#include "sysemu/cpu-throttle.h"
+#include "sysemu/kvm.h"
+#include "qapi/error.h"
+#include "qapi/qapi-commands-migration.h"
  
  static QemuMutex qemu_cpu_list_lock;

  static QemuCond exclusive_cond;
@@ -352,3 +357,39 @@ void process_queued_cpu_work(CPUState *cpu)
  qemu_mutex_unlock(&cpu->work_mutex);
  qemu_cond_broadcast(&qemu_work_cond);
  }
+
+void qmp_set_dirty_limit(int64_t idx,
+ uint64_t dirtyrate,
+ Error **errp)
+{
+if (!kvm_dirty_ring_enabled()) {
+error_setg(errp, "dirty ring not enable, needed by dirty restraint!");


"not enabled"

What is a "dirty restraint"?

Drop the exclamation point, please.  See error.h:

  * The resulting message should be a single phrase, with no newline or
  * trailing punctuation.

What about "setting a dirty page limit requires ...".

Ok, sound good



+return;
+}
+
+dirtylimit_calc();
+dirtylimit_vcpu(idx, dirtyrate);
+}
+
+void qmp_cancel_dirty_limit(int64_t idx,
+Error **errp)
+{
+if (!kvm_dirty_ring_enabled()) {
+error_setg(errp, "dirty ring not enable, needed by dirty restraint!");
+return;
+}
+
+if (unlikely(!dirtylimit_cancel_vcpu(idx))) {
+dirtylimit_calc_quit();
+}
+}
+
+void dirtylimit_setup(int max_cpus)
+{
+if (!kvm_dirty_ring_enabled()) {


This crashes unless the accelerator is kvm.  Reproducer:

 $ qemu-system-x86_64 -display none -accel tcg
 Segmentation fault (core dumped)


Thanks very much for finding this issue, i'll fix it next version


+return;
+}
+
+dirtylimit_calc_state_init(max_cpus);
+dirtylimit_state_init(max_cpus);
+}
diff --git a/include/hw/core/cpu.h b/include/hw/core/cpu.h
index e948e81..11df012 100644
--- a/include/hw/core/cpu.h
+++ b/include/hw/core/cpu.h
@@ -881,6 +881,15 @@ void end_exclusive(void);
   */
  void qemu_init_vcpu(CPUState *cpu);
  
+/**

+ * dirtylimit_setup:
+ *
+ * Initializes the global state of dirtylimit calculation and
+ * dirtylimit itself. This is prepared for vCPU dirtylimit which
+ * could be triggered during vm lifecycle.
+ */
+void dirtylimit_setup(int max_cpus);
+
  #define SSTEP_ENABLE  0x1  /* Enable simulated HW single stepping */
  #define SSTEP_NOIRQ   0x2  /* Do not use IRQ while single stepping */
  #define SSTEP_NOTIMER 0x4  /* Do not Timers while single stepping */
diff --git a/qapi/migration.json b/qapi/migration.json
index bbfd48c..42b260e 100644
--- a/qapi/migration.json
+++ b/qapi/migration.json
@@ -1850,6 +1850,49 @@
  { 'command': 'query-dirty-rate', 'returns': 'DirtyRateInfo' }
  
  ##

+# @set-dirty-limit:
+#
+# Set the upper limit of dirty page rate for the interested vCPU.


"for a vCPU"


+#
+# This command could be used to cap the vCPU memory load, which is also
+# refered as "dirty page rate". Users can use set-dirty-limit unconditionally,
+# but if one want to know which vCPU is in high memory load and which vCPU
+# should be limited, "calc-dirty-rate" with "dirty-ring" mode maybe an
+# availiable method.


I think you should mention that the command fails unless dirty ring is
enabled, and a pointer to its documentation.


Emm, it seems that there's no documentation about dirty ring in qemu,
should i metion the commit b4420f19 "KVM: Dirty ring support" for 
dirty-ring?

+#
+# @idx: vCPU index to set dirtylimit.


Please rename to @cpu-index for consistency with query-cpus-fast.  Same
for cancel-dirty-limit below.


+#
+# @dirtyrate: upper limit for the specified vCPU's dirty page rate (MB/s)


In QMP, we separate words with hyphens, like @dirty-rate.  Please
rename.


+#
+# Since: 6.3


7.0


+#
+# Example:
+#   {"execute": "set-dirty-limit"}
+#"arguments": { "idx": 0,
+#   "dirtyrate": 200 } }
+#
+##
+{ 'command': 'set-dirty-limit',
+  'data': { 'idx': 'int', 'dirtyrate': 'uint64' } }
+
+##
+# @cancel-dirty-limit:
+#
+# Cancel the dirtylimit for the vCPU which has been set with set-dirty-limit.


"the dirty page limit"


+#
+# @idx: vCPU index to canceled the dirtylimit
+#
+# Since: 6.3


7.0


+#
+# Example:
+#   {"e

Re: [PATCH v5 3/3] cpus-common: implement dirty limit on vCPU

2021-11-24 Thread Markus Armbruster
huang...@chinatelecom.cn writes:

> From: Hyman Huang(黄勇) 
>
> Implement dirtyrate calculation periodically basing on
> dirty-ring and throttle vCPU until it reachs the quota
> dirtyrate given by user.
>
> Introduce qmp commands set-dirty-limit/cancel-dirty-limit to
> set/cancel dirty limit on vCPU.
>
> Signed-off-by: Hyman Huang(黄勇) 
> ---
>  cpus-common.c | 41 +
>  include/hw/core/cpu.h |  9 +
>  qapi/migration.json   | 43 +++
>  softmmu/vl.c  |  1 +
>  4 files changed, 94 insertions(+)
>
> diff --git a/cpus-common.c b/cpus-common.c
> index 6e73d3e..43b0078 100644
> --- a/cpus-common.c
> +++ b/cpus-common.c
> @@ -23,6 +23,11 @@
>  #include "hw/core/cpu.h"
>  #include "sysemu/cpus.h"
>  #include "qemu/lockable.h"
> +#include "sysemu/dirtylimit.h"
> +#include "sysemu/cpu-throttle.h"
> +#include "sysemu/kvm.h"
> +#include "qapi/error.h"
> +#include "qapi/qapi-commands-migration.h"
>  
>  static QemuMutex qemu_cpu_list_lock;
>  static QemuCond exclusive_cond;
> @@ -352,3 +357,39 @@ void process_queued_cpu_work(CPUState *cpu)
>  qemu_mutex_unlock(&cpu->work_mutex);
>  qemu_cond_broadcast(&qemu_work_cond);
>  }
> +
> +void qmp_set_dirty_limit(int64_t idx,
> + uint64_t dirtyrate,
> + Error **errp)
> +{
> +if (!kvm_dirty_ring_enabled()) {
> +error_setg(errp, "dirty ring not enable, needed by dirty 
> restraint!");

"not enabled"

What is a "dirty restraint"?

Drop the exclamation point, please.  See error.h:

 * The resulting message should be a single phrase, with no newline or
 * trailing punctuation.

What about "setting a dirty page limit requires ...".

> +return;
> +}
> +
> +dirtylimit_calc();
> +dirtylimit_vcpu(idx, dirtyrate);
> +}
> +
> +void qmp_cancel_dirty_limit(int64_t idx,
> +Error **errp)
> +{
> +if (!kvm_dirty_ring_enabled()) {
> +error_setg(errp, "dirty ring not enable, needed by dirty 
> restraint!");
> +return;
> +}
> +
> +if (unlikely(!dirtylimit_cancel_vcpu(idx))) {
> +dirtylimit_calc_quit();
> +}
> +}
> +
> +void dirtylimit_setup(int max_cpus)
> +{
> +if (!kvm_dirty_ring_enabled()) {

This crashes unless the accelerator is kvm.  Reproducer:

$ qemu-system-x86_64 -display none -accel tcg
Segmentation fault (core dumped)

> +return;
> +}
> +
> +dirtylimit_calc_state_init(max_cpus);
> +dirtylimit_state_init(max_cpus);
> +}
> diff --git a/include/hw/core/cpu.h b/include/hw/core/cpu.h
> index e948e81..11df012 100644
> --- a/include/hw/core/cpu.h
> +++ b/include/hw/core/cpu.h
> @@ -881,6 +881,15 @@ void end_exclusive(void);
>   */
>  void qemu_init_vcpu(CPUState *cpu);
>  
> +/**
> + * dirtylimit_setup:
> + *
> + * Initializes the global state of dirtylimit calculation and
> + * dirtylimit itself. This is prepared for vCPU dirtylimit which
> + * could be triggered during vm lifecycle.
> + */
> +void dirtylimit_setup(int max_cpus);
> +
>  #define SSTEP_ENABLE  0x1  /* Enable simulated HW single stepping */
>  #define SSTEP_NOIRQ   0x2  /* Do not use IRQ while single stepping */
>  #define SSTEP_NOTIMER 0x4  /* Do not Timers while single stepping */
> diff --git a/qapi/migration.json b/qapi/migration.json
> index bbfd48c..42b260e 100644
> --- a/qapi/migration.json
> +++ b/qapi/migration.json
> @@ -1850,6 +1850,49 @@
>  { 'command': 'query-dirty-rate', 'returns': 'DirtyRateInfo' }
>  
>  ##
> +# @set-dirty-limit:
> +#
> +# Set the upper limit of dirty page rate for the interested vCPU.

"for a vCPU"

> +#
> +# This command could be used to cap the vCPU memory load, which is also
> +# refered as "dirty page rate". Users can use set-dirty-limit 
> unconditionally,
> +# but if one want to know which vCPU is in high memory load and which vCPU
> +# should be limited, "calc-dirty-rate" with "dirty-ring" mode maybe an
> +# availiable method.

I think you should mention that the command fails unless dirty ring is
enabled, and a pointer to its documentation.

> +#
> +# @idx: vCPU index to set dirtylimit.

Please rename to @cpu-index for consistency with query-cpus-fast.  Same
for cancel-dirty-limit below.

> +#
> +# @dirtyrate: upper limit for the specified vCPU's dirty page rate (MB/s)

In QMP, we separate words with hyphens, like @dirty-rate.  Please
rename.

> +#
> +# Since: 6.3

7.0

> +#
> +# Example:
> +#   {"execute": "set-dirty-limit"}
> +#"arguments": { "idx": 0,
> +#   "dirtyrate": 200 } }
> +#
> +##
> +{ 'command': 'set-dirty-limit',
> +  'data': { 'idx': 'int', 'dirtyrate': 'uint64' } }
> +
> +##
> +# @cancel-dirty-limit:
> +#
> +# Cancel the dirtylimit for the vCPU which has been set with set-dirty-limit.

"the dirty page limit"

> +#
> +# @idx: vCPU index to canceled the dirtylimit
> +#
> +# Since: 6.3

7.0

> +#
> +# Example:
> +#   {"execute": "cancel-dirty-limit"}
> +#"arguments": 

[PATCH v5 3/3] cpus-common: implement dirty limit on vCPU

2021-11-24 Thread huangy81
From: Hyman Huang(黄勇) 

Implement dirtyrate calculation periodically basing on
dirty-ring and throttle vCPU until it reachs the quota
dirtyrate given by user.

Introduce qmp commands set-dirty-limit/cancel-dirty-limit to
set/cancel dirty limit on vCPU.

Signed-off-by: Hyman Huang(黄勇) 
---
 cpus-common.c | 41 +
 include/hw/core/cpu.h |  9 +
 qapi/migration.json   | 43 +++
 softmmu/vl.c  |  1 +
 4 files changed, 94 insertions(+)

diff --git a/cpus-common.c b/cpus-common.c
index 6e73d3e..43b0078 100644
--- a/cpus-common.c
+++ b/cpus-common.c
@@ -23,6 +23,11 @@
 #include "hw/core/cpu.h"
 #include "sysemu/cpus.h"
 #include "qemu/lockable.h"
+#include "sysemu/dirtylimit.h"
+#include "sysemu/cpu-throttle.h"
+#include "sysemu/kvm.h"
+#include "qapi/error.h"
+#include "qapi/qapi-commands-migration.h"
 
 static QemuMutex qemu_cpu_list_lock;
 static QemuCond exclusive_cond;
@@ -352,3 +357,39 @@ void process_queued_cpu_work(CPUState *cpu)
 qemu_mutex_unlock(&cpu->work_mutex);
 qemu_cond_broadcast(&qemu_work_cond);
 }
+
+void qmp_set_dirty_limit(int64_t idx,
+ uint64_t dirtyrate,
+ Error **errp)
+{
+if (!kvm_dirty_ring_enabled()) {
+error_setg(errp, "dirty ring not enable, needed by dirty restraint!");
+return;
+}
+
+dirtylimit_calc();
+dirtylimit_vcpu(idx, dirtyrate);
+}
+
+void qmp_cancel_dirty_limit(int64_t idx,
+Error **errp)
+{
+if (!kvm_dirty_ring_enabled()) {
+error_setg(errp, "dirty ring not enable, needed by dirty restraint!");
+return;
+}
+
+if (unlikely(!dirtylimit_cancel_vcpu(idx))) {
+dirtylimit_calc_quit();
+}
+}
+
+void dirtylimit_setup(int max_cpus)
+{
+if (!kvm_dirty_ring_enabled()) {
+return;
+}
+
+dirtylimit_calc_state_init(max_cpus);
+dirtylimit_state_init(max_cpus);
+}
diff --git a/include/hw/core/cpu.h b/include/hw/core/cpu.h
index e948e81..11df012 100644
--- a/include/hw/core/cpu.h
+++ b/include/hw/core/cpu.h
@@ -881,6 +881,15 @@ void end_exclusive(void);
  */
 void qemu_init_vcpu(CPUState *cpu);
 
+/**
+ * dirtylimit_setup:
+ *
+ * Initializes the global state of dirtylimit calculation and
+ * dirtylimit itself. This is prepared for vCPU dirtylimit which
+ * could be triggered during vm lifecycle.
+ */
+void dirtylimit_setup(int max_cpus);
+
 #define SSTEP_ENABLE  0x1  /* Enable simulated HW single stepping */
 #define SSTEP_NOIRQ   0x2  /* Do not use IRQ while single stepping */
 #define SSTEP_NOTIMER 0x4  /* Do not Timers while single stepping */
diff --git a/qapi/migration.json b/qapi/migration.json
index bbfd48c..42b260e 100644
--- a/qapi/migration.json
+++ b/qapi/migration.json
@@ -1850,6 +1850,49 @@
 { 'command': 'query-dirty-rate', 'returns': 'DirtyRateInfo' }
 
 ##
+# @set-dirty-limit:
+#
+# Set the upper limit of dirty page rate for the interested vCPU.
+#
+# This command could be used to cap the vCPU memory load, which is also
+# refered as "dirty page rate". Users can use set-dirty-limit unconditionally,
+# but if one want to know which vCPU is in high memory load and which vCPU
+# should be limited, "calc-dirty-rate" with "dirty-ring" mode maybe an
+# availiable method.
+#
+# @idx: vCPU index to set dirtylimit.
+#
+# @dirtyrate: upper limit for the specified vCPU's dirty page rate (MB/s)
+#
+# Since: 6.3
+#
+# Example:
+#   {"execute": "set-dirty-limit"}
+#"arguments": { "idx": 0,
+#   "dirtyrate": 200 } }
+#
+##
+{ 'command': 'set-dirty-limit',
+  'data': { 'idx': 'int', 'dirtyrate': 'uint64' } }
+
+##
+# @cancel-dirty-limit:
+#
+# Cancel the dirtylimit for the vCPU which has been set with set-dirty-limit.
+#
+# @idx: vCPU index to canceled the dirtylimit
+#
+# Since: 6.3
+#
+# Example:
+#   {"execute": "cancel-dirty-limit"}
+#"arguments": { "idx": 0 } }
+#
+##
+{ 'command': 'cancel-dirty-limit',
+  'data': { 'idx': 'int' } }
+
+##
 # @snapshot-save:
 #
 # Save a VM snapshot
diff --git a/softmmu/vl.c b/softmmu/vl.c
index 620a1f1..0f83ce3 100644
--- a/softmmu/vl.c
+++ b/softmmu/vl.c
@@ -3777,5 +3777,6 @@ void qemu_init(int argc, char **argv, char **envp)
 qemu_init_displays();
 accel_setup_post(current_machine);
 os_setup_post();
+dirtylimit_setup(current_machine->smp.max_cpus);
 resume_mux_open();
 }
-- 
1.8.3.1