From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from netrider.rowland.org (netrider.rowland.org [192.131.102.5]) by smtp.subspace.kernel.org (Postfix) with SMTP id 6F8573D968 for ; Thu, 11 Apr 2024 16:30:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.131.102.5 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712853011; cv=none; b=c6+KkrX3jRsO2GzB/1yBfvvqfuipbc8rbWxmzLdw4/0YbtY7YpB0QAjXTR0FmihETthQyuo8WggzhLkxssKLGQGiCllC8uBLulJ5lY5rG1SN+88AjK48B3SLgjo9sQQpDz69HyVjG97SMP5N4XhQjLK7KxY11OmzElpEufE91x8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712853011; c=relaxed/simple; bh=OqFFjJsjtdY+SN6BBo/d83Hd1BfzuyDTm6JRlX7dhmM=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=X4Puq3+SnkaGdSmFWc+mYqAIpzUibrvRnjMc2l295g+DUudbJi44Zn3bQSlm99pTrLdwVTO7Sc8Av5zxbPSW8FWhfS6QsKc7ikKfIncBL46A6LVe5vX9c99KKwnPMrhVIcAEXDt8zGFh+L9mRDkPNEgg3CYFQCbEjg7btlkCde8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=rowland.harvard.edu; spf=pass smtp.mailfrom=netrider.rowland.org; arc=none smtp.client-ip=192.131.102.5 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=rowland.harvard.edu Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=netrider.rowland.org Received: (qmail 250765 invoked by uid 1000); 11 Apr 2024 12:30:08 -0400 Date: Thu, 11 Apr 2024 12:30:08 -0400 From: Alan Stern To: Marcello Sylvester Bauer Cc: linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, Greg Kroah-Hartman , Marcello Sylvester Bauer , Matthias Stoeckl , Uwe Kleine-Koenig Subject: Re: [PATCH v1 1/2] usb: gadget: dummy_hcd: Switch to hrtimer transfer scheduler Message-ID: References: <57a1c2180ff74661600e010c234d1dbaba1d0d46.1712843963.git.sylv@sylv.io> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <57a1c2180ff74661600e010c234d1dbaba1d0d46.1712843963.git.sylv@sylv.io> On Thu, Apr 11, 2024 at 05:22:10PM +0200, Marcello Sylvester Bauer wrote: > The dummy_hcd transfer scheduler assumes that the internal kernel timer > frequency is set to 1000Hz to give a polling interval of 1ms. Reducing > the timer frequency will result in an anti-proportional reduction in > transfer performance. Switch to a hrtimer to decouple this association. > > Signed-off-by: Marcello Sylvester Bauer > Signed-off-by: Marcello Sylvester Bauer > --- Reviewed-by: Alan Stern