From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: [PATCH] net: dccp: Replace GFP_ATOMIC with GFP_KERNEL in dccp_init Date: Mon, 9 Apr 2018 07:42:20 -0700 Message-ID: <8216dee8-5e52-421e-026a-4c75d654be54@gmail.com> References: <1523283004-25581-1-git-send-email-baijiaju1990@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: dccp@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org To: Jia-Ju Bai , gerrit@erg.abdn.ac.uk, davem@davemloft.net Return-path: In-Reply-To: <1523283004-25581-1-git-send-email-baijiaju1990@gmail.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On 04/09/2018 07:10 AM, Jia-Ju Bai wrote: > dccp_init() is never called in atomic context. > This function is only set as a parameter of module_init(). > > Despite never getting called from atomic context, > dccp_init() calls __get_free_pages() with GFP_ATOMIC, > which waits busily for allocation. What do you mean by "waits busily" ? GFP_ATOMIC does not sleep, does not wait. > GFP_ATOMIC is not necessary and can be replaced with GFP_KERNEL, > to avoid busy waiting and improve the possibility of sucessful allocation. > > This is found by a static analysis tool named DCNS written by myself. > And I also manually check it. > > Signed-off-by: Jia-Ju Bai > ---