Re: [PATCH 1/3] jump label: add enabled/disabled state to jump label key entries

[Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>]

* Jason Baron (jbaron@redhat.com) wrote:
[...]
> +static void update_jump_label_module(struct module *mod)
> +{
> +	struct hlist_head *head;
> +	struct hlist_node *node, *node_next, *module_node, *module_node_next;
> +	struct jump_label_entry *e;
> +	struct jump_label_module_entry *e_module;
> +	struct jump_entry *iter;
> +	int i, count;
> +
> +	/* if the module doesn't have jump label entries, just return */
> +	if (!mod->num_jump_entries)
> +		return;
> +
> +	for (i = 0; i < JUMP_LABEL_TABLE_SIZE; i++) {
> +		head = &jump_label_table[i];
> +		hlist_for_each_entry_safe(e, node, node_next, head, hlist) {
> +			if (!e->enabled)
> +				continue;
> +			hlist_for_each_entry_safe(e_module, module_node,
> +						  module_node_next,
> +						  &(e->modules), hlist) {
> +				if (e_module->mod != mod)
> +					continue;

Ouch.

Could you iterate on the loaded/unloaded module jump labels and do hash
table lookups rather than doing this O(n^3) iteration ?

Thanks,

Mathieu

-- 
Mathieu Desnoyers
Operating System Efficiency R&D Consultant
EfficiOS Inc.
http://www.efficios.com