From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bartlomiej Zolnierkiewicz Date: Tue, 24 Apr 2018 15:42:51 +0000 Subject: Re: [PATCH] video: fbdev: savage: Replace mdelay with usleep_range in savage_init_hw Message-Id: <7431484.AHk4tMfvN6@amdc3058> List-Id: References: <1523322359-27598-1-git-send-email-baijiaju1990@gmail.com> In-Reply-To: <1523322359-27598-1-git-send-email-baijiaju1990@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Jia-Ju Bai Cc: adaplas@gmail.com, linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org On Tuesday, April 10, 2018 09:05:59 AM Jia-Ju Bai wrote: > savage_init_hw() is never called in atomic context. > > The call chains ending up at savage_init_hw() are: > [1] savage_init_hw() <- savagefb_probe() > [2] savage_init_hw() <- savagefb_resume() > > savagefb_probe() is only set as ".probe" in struct pci_driver. > savagefb_resume) is only set as ".resume" in struct pci_driver. > These functions are not called in atomic context. > > Despite never getting called from atomic context, savage_init_hw() > calls mdelay() to busily wait. > This is not necessary and can be replaced with usleep_range to > avoid busy waiting. > > 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 Patch queued for 4.18, thanks. Best regards, -- Bartlomiej Zolnierkiewicz Samsung R&D Institute Poland Samsung Electronics