Re: [PATCH v3] of: cache phandle nodes to reduce cost of of_find_node_by_phandle()

Chintan Pandya
2018-02-28T13:27:14Z

On 2/15/2018 6:22 AM, frowand.list@gmail.com wrote:

> +static void of_populate_phandle_cache(void)
> +{
> + unsigned long flags;
> + u32 cache_entries;
> + struct device_node *np;
> + u32 phandles = 0;
> +
> + raw_spin_lock_irqsave(&devtree_lock, flags);
> +
> + kfree(phandle_cache);
> + phandle_cache = NULL;
> +
> + for_each_of_allnodes(np)
> + if (np->phandle && np->phandle != OF_PHANDLE_ILLEGAL)
> + phandles++;
> +
> + cache_entries = roundup_pow_of_two(phandles);
> + phandle_cache_mask = cache_entries - 1;
> +
> + phandle_cache = kcalloc(cache_entries, sizeof(*phandle_cache),
> + GFP_ATOMIC);
> +

NULL check of phandle_cache would be good to have.

> + for_each_of_allnodes(np)
> + if (np->phandle && np->phandle != OF_PHANDLE_ILLEGAL)
> + phandle_cache[np->phandle & phandle_cache_mask] = np;
> +
> + raw_spin_unlock_irqrestore(&devtree_lock, flags);
> +}

Chintan
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