From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chintan Pandya Subject: Re: [PATCH v3] of: cache phandle nodes to reduce cost of of_find_node_by_phandle() Date: Wed, 28 Feb 2018 18:57:08 +0530 Message-ID: References: <1518655979-10910-1-git-send-email-frowand.list@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1518655979-10910-1-git-send-email-frowand.list@gmail.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: frowand.list@gmail.com, Rob Herring Cc: devicetree@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: devicetree@vger.kernel.org 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 -- Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project