Paolo Bonzini <pbonz...@redhat.com> writes:
> Allow retrieving the statistics from a specific provider only.
> This can be used in the future by HMP commands such as "info
> sync-profile" or "info profile". The next patch also adds
> filter-by-provider capabilities to the HMP equivalent of
> query-stats, "info stats".
>
> Example:
>
> { "execute": "query-stats",
> "arguments": {
> "target": "vm",
> "providers": [
> { "provider": "kvm" } ] } }
>
> The QAPI is a bit more verbose than just a list of StatsProvider,
> so that it can be subsequently extended with filtering of statistics
> by name.
>
> Extracted from a patch by Mark Kanda.
>
> Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
> ---
> accel/kvm/kvm-all.c | 3 ++-
> include/monitor/stats.h | 4 +++-
> monitor/hmp-cmds.c | 2 +-
> monitor/qmp-cmds.c | 45 ++++++++++++++++++++++++++++++++---------
> qapi/stats.json | 17 ++++++++++++++--
> 5 files changed, 56 insertions(+), 15 deletions(-)
>
> diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
> index 3ee431a431..461b6cf927 100644
> --- a/accel/kvm/kvm-all.c
> +++ b/accel/kvm/kvm-all.c
> @@ -2644,7 +2644,8 @@ static int kvm_init(MachineState *ms)
> }
>
> if (kvm_check_extension(kvm_state, KVM_CAP_BINARY_STATS_FD)) {
> - add_stats_callbacks(query_stats_cb, query_stats_schemas_cb);
> + add_stats_callbacks(STATS_PROVIDER_KVM, query_stats_cb,
> + query_stats_schemas_cb);
> }
>
> return 0;
> diff --git a/include/monitor/stats.h b/include/monitor/stats.h
> index 8c50feeaa9..840c4ed08e 100644
> --- a/include/monitor/stats.h
> +++ b/include/monitor/stats.h
> @@ -17,10 +17,12 @@ typedef void SchemaRetrieveFunc(StatsSchemaList **result,
> Error **errp);
> /*
> * Register callbacks for the QMP query-stats command.
> *
> + * @provider: stats provider
Argument documentation that merely paraphrases the type is redundant.
May I have a proper contract?
> * @stats_fn: routine to query stats:
> * @schema_fn: routine to query stat schemas:
> */
> -void add_stats_callbacks(StatRetrieveFunc *stats_fn,
> +void add_stats_callbacks(StatsProvider provider,
> + StatRetrieveFunc *stats_fn,
> SchemaRetrieveFunc *schemas_fn);
>
> /*
> diff --git a/monitor/hmp-cmds.c b/monitor/hmp-cmds.c
> index c0cb440902..8d2c4792d5 100644
> --- a/monitor/hmp-cmds.c
> +++ b/monitor/hmp-cmds.c
> @@ -2394,7 +2394,7 @@ void hmp_info_stats(Monitor *mon, const QDict *qdict)
> goto exit_no_print;
> }
>
> - schema = qmp_query_stats_schemas(&err);
> + schema = qmp_query_stats_schemas(false, 0, &err);
NULL instead of 0 please.
> if (err) {
> goto exit;
> }
> diff --git a/monitor/qmp-cmds.c b/monitor/qmp-cmds.c
> index ebf6f49446..7be0e7414a 100644
> --- a/monitor/qmp-cmds.c
> +++ b/monitor/qmp-cmds.c
> @@ -445,6 +445,7 @@ HumanReadableText *qmp_x_query_irq(Error **errp)
> }
>
> typedef struct StatsCallbacks {
> + StatsProvider provider;
> StatRetrieveFunc *stats_cb;
> SchemaRetrieveFunc *schemas_cb;
> QTAILQ_ENTRY(StatsCallbacks) next;
> @@ -453,16 +454,34 @@ typedef struct StatsCallbacks {
> static QTAILQ_HEAD(, StatsCallbacks) stats_callbacks =
> QTAILQ_HEAD_INITIALIZER(stats_callbacks);
>
> -void add_stats_callbacks(StatRetrieveFunc *stats_fn,
> +void add_stats_callbacks(StatsProvider provider,
> + StatRetrieveFunc *stats_fn,
> SchemaRetrieveFunc *schemas_fn)
> {
> StatsCallbacks *entry = g_new(StatsCallbacks, 1);
> + entry->provider = provider;
> entry->stats_cb = stats_fn;
> entry->schemas_cb = schemas_fn;
>
> QTAILQ_INSERT_TAIL(&stats_callbacks, entry, next);
> }
>
> +static bool stats_provider_requested(StatsProvider provider,
> + StatsFilter *filter)
> +{
> + StatsRequestList *request;
> +
> + if (!filter->has_providers) {
> + return true;
> + }
> + for (request = filter->providers; request; request = request->next) {
> + if (request->value->provider == provider) {
> + return true;
> + }
> + }
> + return false;
> +}
> +
This is just like apply_str_list_filter(). Good! Could we make the two
names similar, too?
> StatsResultList *qmp_query_stats(StatsFilter *filter, Error **errp)
> {
> StatsResultList *stats_results = NULL;
> @@ -487,27 +506,33 @@ StatsResultList *qmp_query_stats(StatsFilter *filter,
> Error **errp)
> }
>
> QTAILQ_FOREACH(entry, &stats_callbacks, next) {
> - entry->stats_cb(&stats_results, filter->target, targets, errp);
> - if (*errp) {
> - qapi_free_StatsResultList(stats_results);
> - return NULL;
> + if (stats_provider_requested(entry->provider, filter)) {
> + entry->stats_cb(&stats_results, filter->target, targets, errp);
> + if (*errp) {
> + qapi_free_StatsResultList(stats_results);
> + return NULL;
> + }
I like if (!wanted) continue in such loops for less nesting. Clearly a
matter of taste.
> }
> }
>
> return stats_results;
> }
>
> -StatsSchemaList *qmp_query_stats_schemas(Error **errp)
> +StatsSchemaList *qmp_query_stats_schemas(bool has_provider,
> + StatsProvider provider,
> + Error **errp)
> {
> StatsSchemaList *stats_results = NULL;
> StatsCallbacks *entry;
> ERRP_GUARD();
>
> QTAILQ_FOREACH(entry, &stats_callbacks, next) {
> - entry->schemas_cb(&stats_results, errp);
> - if (*errp) {
> - qapi_free_StatsSchemaList(stats_results);
> - return NULL;
> + if (!has_provider || provider == entry->provider) {
> + entry->schemas_cb(&stats_results, errp);
> + if (*errp) {
> + qapi_free_StatsSchemaList(stats_results);
> + return NULL;
> + }
Likewise.
> }
> }
>
> diff --git a/qapi/stats.json b/qapi/stats.json
> index e8ed907793..b75bb86124 100644
> --- a/qapi/stats.json
> +++ b/qapi/stats.json
> @@ -68,6 +68,18 @@
> { 'enum': 'StatsTarget',
> 'data': [ 'vm', 'vcpu' ] }
>
> +##
> +# @StatsRequest:
> +#
> +# Indicates a set of statistics that should be returned by query-stats.
> +#
> +# @provider: provider for which to return statistics.
> +#
> +# Since: 7.1
> +##
> +{ 'struct': 'StatsRequest',
> + 'data': { 'provider': 'StatsProvider' } }
> +
> ##
> # @StatsVCPUFilter:
> #
> @@ -85,11 +97,12 @@
> # request statistics and optionally the required subset of information for
> # that target:
> # - which vCPUs to request statistics for
> +# - which provider to request statistics from
> #
> # Since: 7.1
> ##
> { 'union': 'StatsFilter',
> - 'base': { 'target': 'StatsTarget' },
> + 'base': { 'target': 'StatsTarget', '*providers': [ 'StatsRequest' ]
> },
Easier to read, I think:
'base': {
'target': 'StatsTarget',
'*providers': [ 'StatsRequest' ] },
> 'discriminator': 'target',
> 'data': { 'vcpu': 'StatsVCPUFilter' } }
>
> @@ -225,5 +238,5 @@
> # Since: 7.1
> ##
> { 'command': 'query-stats-schemas',
> - 'data': { },
> + 'data': { '*provider': 'StatsProvider' },
> 'returns': [ 'StatsSchema' ] }
Only the "NULL instead of 0" is a request, the remainder suggestions.
So, with that request addressed
Reviewed-by: Markus Armbruster <arm...@redhat.com>
PS: Consider adding
[diff]
orderFile = scripts/git.orderfile
to your .git/config.
