From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Subject: Re: [PATCH]: Let I/O engine provide methods to allocate/free I/O memory. References: <56CCD5D1.3020508@kernel.dk> From: Jens Axboe Message-ID: <56CCD778.9070701@kernel.dk> Date: Tue, 23 Feb 2016 15:04:40 -0700 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit To: Andrey Kuzmin Cc: fio@vger.kernel.org List-ID: On 02/23/2016 03:02 PM, Andrey Kuzmin wrote: > > On Feb 24, 2016 00:57, "Jens Axboe" > wrote: > > > > On 02/23/2016 02:16 PM, Andrey Kuzmin wrote: > >> > >> I/O engine may have special needs as to how the I/O memory should be > >> allocated. The below patch adds respective methods to the I/O engine > >> interface. > > > > > > What kind of special needs? It's not that I mind adding an IO engine > alloc hook, the only issue is that it potentially voids the various job > file settings for memory backing etc without the user knowing it. So I > think we need some decent justification here, other than "special needs" :-) > > > > My engine talks directly to the hardware, and has to comply with the > hardware requirements re the io memory. Is that enough justification ;)? Maybe :-) What are those requirements? Is it just alignment? -- Jens Axboe