Re: [Qemu-devel] [PATCH v4 08/11] numa: Extend the command-line to provide memory latency and bandwidth information

[Igor Mammedov]

On Wed,  8 May 2019 14:17:23 +0800
Tao Xu <address@hidden> wrote:

> From: Liu Jingqi <address@hidden>
> 
> Add -numa hmat-lb option to provide System Locality Latency and
> Bandwidth Information. These memory attributes help to build
> System Locality Latency and Bandwidth Information Structure(s)
> in ACPI Heterogeneous Memory Attribute Table (HMAT).
> 
> Signed-off-by: Liu Jingqi <address@hidden>
> Signed-off-by: Tao Xu <address@hidden>
> ---
> 
> Changes in v4 -> v3:
>     - update the version tag from 4.0 to 4.1
> ---
>  numa.c          | 127 ++++++++++++++++++++++++++++++++++++++++++++++++
>  qapi/misc.json  |  94 ++++++++++++++++++++++++++++++++++-
>  qemu-options.hx |  28 ++++++++++-
>  3 files changed, 246 insertions(+), 3 deletions(-)
> 
> diff --git a/numa.c b/numa.c
> index 71b0aee02a..1aecb7a2e9 100644
> --- a/numa.c
> +++ b/numa.c
> @@ -40,6 +40,7 @@
>  #include "qemu/option.h"
>  #include "qemu/config-file.h"
>  #include "qemu/cutils.h"
> +#include "hw/acpi/hmat.h"
>  
>  QemuOptsList qemu_numa_opts = {
>      .name = "numa",
> @@ -179,6 +180,126 @@ void parse_numa_distance(MachineState *ms, 
> NumaDistOptions *dist, Error **errp)
>      ms->numa_state->have_numa_distance = true;
>  }
>  
> +static void parse_numa_hmat_lb(MachineState *ms, NumaHmatLBOptions *node,
> +                               Error **errp)
> +{
> +    int nb_numa_nodes = ms->numa_state->num_nodes;
> +    NodeInfo *numa_info = ms->numa_state->nodes;
> +    HMAT_LB_Info *hmat_lb = NULL;
> +
> +    if (node->data_type <= HMATLB_DATA_TYPE_WRITE_LATENCY) {
> +        if (!node->has_latency) {
> +            error_setg(errp, "Missing 'latency' option.");
> +            return;
> +        }
> +        if (node->has_bandwidth) {
> +            error_setg(errp, "Invalid option 'bandwidth' since "
> +                       "the data type is latency.");
> +            return;
> +        }
> +        if (node->has_base_bw) {
> +            error_setg(errp, "Invalid option 'base_bw' since "
> +                       "the data type is latency.");
> +            return;
> +        }
> +    }
> +
> +    if (node->data_type >= HMATLB_DATA_TYPE_ACCESS_BANDWIDTH) {
> +        if (!node->has_bandwidth) {
> +            error_setg(errp, "Missing 'bandwidth' option.");
> +            return;
> +        }
> +        if (node->has_latency) {
> +            error_setg(errp, "Invalid option 'latency' since "
> +                       "the data type is bandwidth.");
> +            return;
> +        }
> +        if (node->has_base_lat) {
> +            error_setg(errp, "Invalid option 'base_lat' since "
> +                       "the data type is bandwidth.");
> +            return;
> +        }
> +    }
> +
> +    if (node->initiator >= nb_numa_nodes) {
> +        error_setg(errp, "Invalid initiator=%"
> +                   PRIu16 ", it should be less than %d.",
> +                   node->initiator, nb_numa_nodes);
> +        return;
> +    }
> +    if (!numa_info[node->initiator].is_initiator) {
> +        error_setg(errp, "Invalid initiator=%"
> +                   PRIu16 ", it isn't an initiator proximity domain.",
> +                   node->initiator);
> +        return;
> +    }
> +
> +    if (node->target >= nb_numa_nodes) {
> +        error_setg(errp, "Invalid initiator=%"
Shouldn't it be 'target' here

> +                   PRIu16 ", it should be less than %d.",
> +                   node->target, nb_numa_nodes);
> +        return;
> +    }
> +    if (!numa_info[node->target].is_target) {
> +        error_setg(errp, "Invalid target=%"
> +                   PRIu16 ", it isn't a target proximity domain.",
> +                   node->target);
> +        return;
> +    }
> +
> +    if (node->has_latency) {
> +        hmat_lb = ms->numa_state->hmat_lb[node->hierarchy][node->data_type];
> +
> +        if (!hmat_lb) {
> +            hmat_lb = g_malloc0(sizeof(*hmat_lb));
> +            ms->numa_state->hmat_lb[node->hierarchy][node->data_type] = 
> hmat_lb;
> +        } else if (hmat_lb->latency[node->initiator][node->target]) {
> +            error_setg(errp, "Duplicate configuration of the latency for "
> +                       "initiator=%" PRIu16 " and target=%" PRIu16 ".",
> +                       node->initiator, node->target);
> +            return;
> +        }
> +
> +        /* Only the first time of setting the base unit is valid. */
> +        if ((hmat_lb->base_lat == 0) && (node->has_base_lat)) {
> +            hmat_lb->base_lat = node->base_lat;
> +        }
> +
> +        hmat_lb->latency[node->initiator][node->target] = node->latency;
> +    }
> +
> +    if (node->has_bandwidth) {
> +        hmat_lb = ms->numa_state->hmat_lb[node->hierarchy][node->data_type];
> +
> +        if (!hmat_lb) {
> +            hmat_lb = g_malloc0(sizeof(*hmat_lb));
> +            ms->numa_state->hmat_lb[node->hierarchy][node->data_type] = 
> hmat_lb;
> +        } else if (hmat_lb->bandwidth[node->initiator][node->target]) {
> +            error_setg(errp, "Duplicate configuration of the bandwidth for "
> +                       "initiator=%" PRIu16 " and target=%" PRIu16 ".",
> +                       node->initiator, node->target);
> +            return;
> +        }
> +
> +        /* Only the first time of setting the base unit is valid. */
> +        if (hmat_lb->base_bw == 0) {
> +            if (!node->has_base_bw) {
> +                error_setg(errp, "Missing 'base-bw' option");
> +                return;
> +            } else {
> +                hmat_lb->base_bw = node->base_bw;
> +            }
> +        }
> +
> +        hmat_lb->bandwidth[node->initiator][node->target] = node->bandwidth;
> +    }
> +
> +    if (hmat_lb) {
> +        hmat_lb->hierarchy = node->hierarchy;
> +        hmat_lb->data_type = node->data_type;
> +    }
> +}
> +
>  static
>  void set_numa_options(MachineState *ms, NumaOptions *object, Error **errp)
>  {
> @@ -217,6 +338,12 @@ void set_numa_options(MachineState *ms, NumaOptions 
> *object, Error **errp)
>          machine_set_cpu_numa_node(ms, 
> qapi_NumaCpuOptions_base(&object->u.cpu),
>                                    &err);
>          break;
> +    case NUMA_OPTIONS_TYPE_HMAT_LB:
> +        parse_numa_hmat_lb(ms, &object->u.hmat_lb, &err);
> +        if (err) {
> +            goto end;
> +        }
> +        break;
>      default:
>          abort();
>      }
> diff --git a/qapi/misc.json b/qapi/misc.json
> index 8b3ca4fdd3..d7fce75702 100644
> --- a/qapi/misc.json
> +++ b/qapi/misc.json
> @@ -2539,10 +2539,12 @@
>  #
>  # @cpu: property based CPU(s) to node mapping (Since: 2.10)
>  #
> +# @hmat-lb: memory latency and bandwidth information (Since: 4.1)
> +#
>  # Since: 2.1
>  ##
>  { 'enum': 'NumaOptionsType',
> -  'data': [ 'node', 'dist', 'cpu' ] }
> +  'data': [ 'node', 'dist', 'cpu', 'hmat-lb' ] }
>  
>  ##
>  # @NumaOptions:
> @@ -2557,7 +2559,8 @@
>    'data': {
>      'node': 'NumaNodeOptions',
>      'dist': 'NumaDistOptions',
> -    'cpu': 'NumaCpuOptions' }}
> +    'cpu': 'NumaCpuOptions',
> +    'hmat-lb': 'NumaHmatLBOptions' }}
>  
>  ##
>  # @NumaNodeOptions:
> @@ -2620,6 +2623,93 @@
>     'base': 'CpuInstanceProperties',
>     'data' : {} }
>  
> +##
> +# @HmatLBMemoryHierarchy:
> +#
> +# The memory hierarchy in the System Locality Latency
> +# and Bandwidth Information Structure of HMAT (Heterogeneous
> +# Memory Attribute Table)
> +#
> +# @memory: the structure represents the memory performance
> +#
> +# @last-level: last level memory of memory side cached memory
> +#
> +# @first-level: first level memory of memory side cached memory
> +#
> +# @second-level: second level memory of memory side cached memory
> +#
> +# @third-level: third level memory of memory side cached memory
> +#
> +# Since: 4.1
> +##
> +{ 'enum': 'HmatLBMemoryHierarchy',
> +  'data': [ 'memory', 'last-level', 'first-level',
> +            'second-level', 'third-level' ] }
> +
> +##
> +# @HmatLBDataType:
> +#
> +# Data type in the System Locality Latency
> +# and Bandwidth Information Structure of HMAT (Heterogeneous
> +# Memory Attribute Table)
> +#
> +# @access-latency: access latency (nanoseconds)
> +#
> +# @read-latency: read latency (nanoseconds)
> +#
> +# @write-latency: write latency (nanoseconds)
> +#
> +# @access-bandwidth: access bandwidth (MB/s)
> +#
> +# @read-bandwidth: read bandwidth (MB/s)
> +#
> +# @write-bandwidth: write bandwidth (MB/s)
> +#
> +# Since: 4.1
> +##
> +{ 'enum': 'HmatLBDataType',
> +  'data': [ 'access-latency', 'read-latency', 'write-latency',
> +            'access-bandwidth', 'read-bandwidth', 'write-bandwidth' ] }
> +
> +##
> +# @NumaHmatLBOptions:
> +#
> +# Set the system locality latency and bandwidth information
> +# between Initiator and Target proximity Domains.
> +#
> +# @initiator: the Initiator Proximity Domain.
> +#
> +# @target: the Target Proximity Domain.
> +#
> +# @hierarchy: the Memory Hierarchy. Indicates the performance
> +#             of memory or side cache.
> +#
> +# @data-type: presents the type of data, access/read/write
> +#             latency or hit latency.
> +#
> +# @base-lat: the base unit for latency in nanoseconds.
> +#
> +# @base-bw: the base unit for bandwidth in megabytes per second(MB/s).
> +#
> +# @latency: the value of latency based on Base Unit from @initiator
> +#           to @target proximity domain.
> +#
> +# @bandwidth: the value of bandwidth based on Base Unit between
> +#             @initiator and @target proximity domain.
> +#
> +# Since: 4.1
> +##
> +{ 'struct': 'NumaHmatLBOptions',
> +  'data': {
> +   'initiator': 'uint16',
> +   'target': 'uint16',
> +   'hierarchy': 'HmatLBMemoryHierarchy',
> +   'data-type': 'HmatLBDataType',
I think union will be better here with data-type used as discriminator,
on top of that you'll be able to drop a bit of error checking above since
QAPI's union will not allow user to mix latency and bandwidth.

> +   '*base-lat': 'uint64',
> +   '*base-bw': 'uint64',
> +   '*latency': 'uint16',
> +   '*bandwidth': 'uint16' }}
> +
>  ##
>  # @HostMemPolicy:
>  #
> diff --git a/qemu-options.hx b/qemu-options.hx
> index 51802cbb26..5351b0e453 100644
> --- a/qemu-options.hx
> +++ b/qemu-options.hx
> @@ -163,16 +163,19 @@ DEF("numa", HAS_ARG, QEMU_OPTION_numa,
>      "-numa node[,mem=size][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n"
>      "-numa node[,memdev=id][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n"
>      "-numa dist,src=source,dst=destination,val=distance\n"
> -    "-numa cpu,node-id=node[,socket-id=x][,core-id=y][,thread-id=z]\n",
> +    "-numa cpu,node-id=node[,socket-id=x][,core-id=y][,thread-id=z]\n"
> +    "-numa 
> hmat-lb,initiator=node,target=node,hierarchy=memory|last-level,data-type=access-latency|read-latency|write-latency[,base-lat=blat][,base-bw=bbw][,latency=lat][,bandwidth=bw]\n",
>      QEMU_ARCH_ALL)
>  STEXI
>  @item -numa 
> node[,address@hidden,address@hidden@var{lastcpu}]][,address@hidden
>  @itemx -numa 
> node[,address@hidden,address@hidden@var{lastcpu}]][,address@hidden
>  @itemx -numa dist,address@hidden,address@hidden,address@hidden
>  @itemx -numa cpu,address@hidden,address@hidden,address@hidden,address@hidden
> address@hidden -numa 
> hmat-lb,address@hidden,address@hidden,address@hidden,address@hidden,address@hidden,address@hidden,address@hidden,address@hidden
>  @findex -numa
>  Define a NUMA node and assign RAM and VCPUs to it.
>  Set the NUMA distance from a source node to a destination node.
> +Set the ACPI Heterogeneous Memory Attribute for the given nodes.

s/Attribute/Attributes/

>  
>  Legacy VCPU assignment uses @samp{cpus} option where
>  @var{firstcpu} and @var{lastcpu} are CPU indexes. Each
> @@ -230,6 +233,29 @@ specified resources, it just assigns existing resources 
> to NUMA
>  nodes. This means that one still has to use the @option{-m},
>  @option{-smp} options to allocate RAM and VCPUs respectively.
>  
> +Use 'hmat-lb' to set System Locality Latency and Bandwidth Information
> +between initiator NUMA node and target NUMA node to build ACPI Heterogeneous 
> Attribute Memory Table (HMAT).
s/ initiator NUMA node and target NUMA node .*\./
initiator and target NUMA nodes in ACPI Heterogeneous Attribute Memory Table 
(HMAT)./

Also I don't see any description of possible values/units


> +Initiator NUMA node can create memory requests, usually including one or 
> more processors.
> +Target NUMA node contains addressable memory.
> +
> +For example:
> address@hidden
> +-m 2G \
> +-smp 3,sockets=2,maxcpus=3 \
> +-numa node,cpus=0-1,nodeid=0 \
> +-numa node,mem=1G,cpus=2,nodeid=1 \
> +-numa node,mem=1G,nodeid=2 \

pls use '-numa cpu' and '-numa memdev' instead of legacy 'cpus/mem' options in 
examples.

> +-numa 
> hmat-lb,initiator=0,target=1,hierarchy=memory,data-type=access-latency,base-lat=10,base-bw=20,latency=10,bandwidth=10
>  \
> +-numa 
> hmat-lb,initiator=1,target=2,hierarchy=first-level,data-type=access-latency,base-bw=10,bandwidth=20
> address@hidden example
> +
> +When the processors in NUMA node 0 access memory in NUMA node 1,
> +the first line containing 'hmat-lb' sets the latency and bandwidth 
> information.
What does it set "FOO information" for?

> +The latency is @var{lat} multiplied by @var{blat} and the bandwidth is 
> @var{bw} multiplied by @var{bbw}.
that's rather cryptic and probably not necessary at all.

> +
> +When the processors in NUMA node 1 access memory in NUMA node 2 that acts as 
> 2nd level memory side cache,
> +the second line containing 'hmat-lb' sets the access hit bandwidth 
> information.
> +
>  ETEXI
>  
>  DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd,