From: Bart Van Assche <Bart.VanAssche@sandisk.com>
To: "tj@kernel.org" <tj@kernel.org>,
        "paolo.valente@linaro.org" <paolo.valente@linaro.org>,
        "axboe@kernel.dk" <axboe@kernel.dk>
CC: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-block@vger.kernel.org" <linux-block@vger.kernel.org>,
        "samuele.zecchini92@gmail.com" <samuele.zecchini92@gmail.com>,
        "fchecconi@gmail.com" <fchecconi@gmail.com>,
        "linus.walleij@linaro.org" <linus.walleij@linaro.org>,
        "avanzini.arianna@gmail.com" <avanzini.arianna@gmail.com>,
        "broonie@kernel.org" <broonie@kernel.org>,
        "riccardo.pizzetti@gmail.com" <riccardo.pizzetti@gmail.com>,
        "ulf.hansson@linaro.org" <ulf.hansson@linaro.org>
Subject: Re: [PATCH V2 11/16] block, bfq: reduce idling only in symmetric
 scenarios
Thread-Topic: [PATCH V2 11/16] block, bfq: reduce idling only in symmetric
 scenarios
Thread-Index: AQHSqjJUxy7EbT23EkylbcVbXyiaLg==
Date: Fri, 31 Mar 2017 15:20:29 +0000
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References: <20170331124743.3530-1-paolo.valente@linaro.org>
         <20170331124743.3530-12-paolo.valente@linaro.org>
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On Fri, 2017-03-31 at 14:47 +0200, Paolo Valente wrote:
> +???????entity->weight_counter = kzalloc(sizeof(struct bfq_weight_counter),
> +??????????????????????????????????????? GFP_ATOMIC);
> +???????entity->weight_counter->weight = entity->weight;

GFP_ATOMIC allocations are more likely to fail than GFP_KERNEL allocations.
What will happen if kzalloc() returns NULL?

Bart.