Re: [PATCH 1/5] perf/x86/intel/uncore: Parse uncore discovery tables

From: Peter Zijlstra
Date: Tue Mar 16 2021 - 07:41:18 EST


On Fri, Mar 12, 2021 at 08:34:34AM -0800, kan.liang@xxxxxxxxxxxxxxx wrote:
> +static struct intel_uncore_discovery_type *
> +search_uncore_discovery_type(u16 type_id)
> +{
> + struct rb_node *node = discovery_tables.rb_node;
> + struct intel_uncore_discovery_type *type;
> +
> + while (node) {
> + type = rb_entry(node, struct intel_uncore_discovery_type, node);
> +
> + if (type->type > type_id)
> + node = node->rb_left;
> + else if (type->type < type_id)
> + node = node->rb_right;
> + else
> + return type;
> + }
> +
> + return NULL;
> +}
> +
> +static struct intel_uncore_discovery_type *
> +add_uncore_discovery_type(struct uncore_unit_discovery *unit)
> +{
> + struct intel_uncore_discovery_type *type, *cur;
> + struct rb_node **node = &discovery_tables.rb_node;
> + struct rb_node *parent = *node;
> +
> + if (unit->access_type >= UNCORE_ACCESS_MAX) {
> + pr_warn("Unsupported access type %d\n", unit->access_type);
> + return NULL;
> + }
> +
> + type = kzalloc(sizeof(struct intel_uncore_discovery_type), GFP_KERNEL);
> + if (!type)
> + return NULL;
> +
> + type->box_ctrl_die = kcalloc(__uncore_max_dies, sizeof(u64), GFP_KERNEL);
> + if (!type->box_ctrl_die)
> + goto free_type;
> +
> + type->access_type = unit->access_type;
> + num_discovered_types[type->access_type]++;
> + type->type = unit->box_type;
> +
> + while (*node) {
> + parent = *node;
> + cur = rb_entry(parent, struct intel_uncore_discovery_type, node);
> +
> + if (cur->type > type->type)
> + node = &parent->rb_left;
> + else
> + node = &parent->rb_right;
> + }
> +
> + rb_link_node(&type->node, parent, node);
> + rb_insert_color(&type->node, &discovery_tables);
> +
> + return type;
> +
> +free_type:
> + kfree(type);
> +
> + return NULL;
> +
> +}

I'm thinking this can use some of this:

2d24dd5798d0 ("rbtree: Add generic add and find helpers")