Thank you Jinpu and John for the review. We are yet to add this support in the driver to make use of the block layer request tag. We are planning to add that feature in our async driver first and see the performance improvements and do a full QA team validation before submitting to open source. The current patch set was created based on our async driver which has been tested by our QA team. We could see some performance boost with these changes as well. Regards, Viswas G > -----Original Message----- > From: Jinpu Wang <jinpu.wang@xxxxxxxxxxxxxxx> > Sent: Friday, September 25, 2020 3:42 PM > To: John Garry <john.garry@xxxxxxxxxx> > Cc: Viswas G <Viswas.G@xxxxxxxxxxxxxxxxx>; Linux SCSI Mailinglist <linux- > scsi@xxxxxxxxxxxxxxx>; Vasanthalakshmi Tharmarajan - I30664 > <Vasanthalakshmi.Tharmarajan@xxxxxxxxxxxxx>; Viswas G - I30667 > <Viswas.G@xxxxxxxxxxxxx>; Ruksar Devadi - I52327 > <Ruksar.devadi@xxxxxxxxxxxxx> > Subject: Re: [PATCH 3/4] pm80xx : Increase the number of outstanding IO > supported > > EXTERNAL EMAIL: Do not click links or open attachments unless you know > the content is safe > > On Fri, Sep 25, 2020 at 11:59 AM John Garry <john.garry@xxxxxxxxxx> > wrote: > > > > On 25/09/2020 07:16, Viswas G wrote: > > > From: Viswas G<Viswas.G@xxxxxxxxxxxxx> > > > > > > Increasing the number of Outstanding IOs from 256 to 1024. > > > CCB and tag are allocated according to outstanding IOs. > > > Also updating the can_queue value (max_out_io - > PM8001_RESERVE_SLOT) > > > to scsi midlayer. > > > > > > Signed-off-by: Viswas G<Viswas.G@xxxxxxxxxxxxx> > > > Signed-off-by: Ruksar Devadi<Ruksar.devadi@xxxxxxxxxxxxx> > > > > Any reason you can't also use the request->tag (instead of generating > > tags internally) for added performance boost? Many other LLDDs do > > this, as managing tags has a performance overhead. > > > > Thanks, > > John > > +1, I think the reason probably is easily compatible with the older kernel. > For upstream one, it makes sense to switch to request->tag. > > Thanks!
