linux-kernel - Re: [PATCH V2 0/4] genirq/affinity: add .calc_sets for improving IRQ allocation & spread

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <alpine.DEB.2.21.1902121438310.3710@nanos.tec.linutronix.de>
Date:   Tue, 12 Feb 2019 14:42:04 +0100 (CET)
From:   Thomas Gleixner <tglx@...utronix.de>
To:     Ming Lei <ming.lei@...hat.com>
cc:     Christoph Hellwig <hch@....de>, Bjorn Helgaas <helgaas@...nel.org>,
        Jens Axboe <axboe@...nel.dk>, linux-block@...r.kernel.org,
        Sagi Grimberg <sagi@...mberg.me>,
        linux-nvme@...ts.infradead.org,
        LKML <linux-kernel@...r.kernel.org>, linux-pci@...r.kernel.org,
        Keith Busch <keith.busch@...el.com>
Subject: Re: [PATCH V2 0/4] genirq/affinity: add .calc_sets for improving
 IRQ allocation & spread

On Tue, 12 Feb 2019, Ming Lei wrote:

> Hi,
> 
> Currently pre-caculated set vectors are provided by driver for
> allocating & spread vectors. This way only works when drivers passes
> same 'max_vecs' and 'min_vecs' to pci_alloc_irq_vectors_affinity(),
> also requires driver to retry the allocating & spread.
> 
> As Bjorn and Keith mentioned, the current usage & interface for irq sets
> is a bit awkward because the retrying should have been avoided by providing
> one resonable 'min_vecs'. However, if 'min_vecs' isn't same with
> 'max_vecs', number of the allocated vectors is unknown before calling
> pci_alloc_irq_vectors_affinity(), then each set's vectors can't be
> pre-caculated.
> 
> Add a new callback of .calc_sets into 'struct irq_affinity' so that
> driver can caculate set vectors after IRQ vector is allocated and
> before spread IRQ vectors. Add 'priv' so that driver may retrieve
> its private data via the 'struct irq_affinity'.
> 
> 
> V2:
> 	- add .calc_sets instead of .setup_affinity() which is easy to
> 	be abused by drivers

This looks really well done. If you can address the minor nitpicks, then
this is good to go, unless someone has objections.

Thanks,

	tglx