From: Michael Ellerman <michael@ellerman.id.au>
To: Alexander Gordeev <agordeev@redhat.com>
Cc: David Laight <David.Laight@ACULAB.COM>,
Mark Lord <kernel@start.ca>, Tejun Heo <tj@kernel.org>,
linux-kernel@vger.kernel.org, Bjorn Helgaas <bhelgaas@google.com>,
Benjamin Herrenschmidt <benh@kernel.crashing.org>,
Ben Hutchings <bhutchings@solarflare.com>,
"H. Peter Anvin" <hpa@zytor.com>,
linux-pci@vger.kernel.org
Subject: Re: [PATCH RFC v2 12/29] PCI/MSI: Introduce pcim_enable_msi*() family helpers
Date: Mon, 28 Oct 2013 09:27:54 +1100 [thread overview]
Message-ID: <1382912874.3371.9.camel@concordia> (raw)
In-Reply-To: <20131025100103.GA317@dhcp-26-207.brq.redhat.com>
On Fri, 2013-10-25 at 12:01 +0200, Alexander Gordeev wrote:
> On Fri, Oct 25, 2013 at 10:10:02AM +0100, David Laight wrote:
> > What this doesn't resolve is a driver requesting a lot of interrupts
> > early on and leaving none for later drivers.
>
> If this problem really exists anywhere besides pSeries?
>
> I can imagine x86 hitting lack of vectors in interrupt table when
> number of CPUs exceeds hundreds, but do we have this problem now?
>
> > Really the system needs to allocate the minimum number to all
> > drivers before giving out any extra ones - I've NFI how this
> > would be arranged!
>
> Do not know. The pSeries quota approach seems more reasonable to me.
When the system boots each driver should get a fair share of the
available MSIs, the quota achieves this.
But ideally the sysadmin would then be able to override that, and give
more MSIs to one device, the quota doesn't allow that.
Hopefully we'll see the number of available MSIs grow faster than the
number required by devices (usually driven by NR_CPUs), and so this will
become a non-problem.
cheers
next prev parent reply other threads:[~2013-10-27 22:27 UTC|newest]
Thread overview: 62+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-10-18 17:12 [PATCH RFC v2 00/29] Introduce pcim_enable_msi*() family helpers Alexander Gordeev
2013-10-18 17:12 ` [PATCH RFC v2 01/29] PCI/MSI/s390: Fix single MSI only check Alexander Gordeev
2013-10-18 17:12 ` [PATCH RFC v2 02/29] PCI/MSI/s390: Remove superfluous check of MSI type Alexander Gordeev
2013-10-18 17:12 ` [PATCH RFC v2 03/29] PCI/MSI/pSeries: Fix wrong error code reporting Alexander Gordeev
2013-10-18 17:12 ` [PATCH RFC v2 04/29] PCI/MSI/pSeries: Make quota traversing and requesting race-safe Alexander Gordeev
2013-11-20 15:43 ` Tejun Heo
2013-10-18 17:12 ` [PATCH RFC v2 05/29] PCI/MSI: Fix return value when populate_msi_sysfs() failed Alexander Gordeev
2013-11-20 15:50 ` Tejun Heo
2013-10-18 17:12 ` [PATCH RFC v2 06/29] PCI/MSI: Get rid of useless count of msi_desc leftovers Alexander Gordeev
2013-11-20 16:07 ` Tejun Heo
2013-11-22 18:27 ` Alexander Gordeev
2013-10-18 17:12 ` [PATCH RFC v2 07/29] PCI/MSI: Return -ENOSYS for unimplemented interfaces, not -1 Alexander Gordeev
2013-11-20 16:07 ` Tejun Heo
2013-10-18 17:12 ` [PATCH RFC v2 08/29] PCI/MSI: Make pci_enable_msix() 'nvec' argument unsigned int Alexander Gordeev
2013-11-20 16:14 ` Tejun Heo
2013-11-22 18:34 ` Alexander Gordeev
2013-10-18 17:12 ` [PATCH RFC v2 09/29] PCI/MSI: Factor out pci_get_msi_cap() interface Alexander Gordeev
2013-11-20 16:18 ` Tejun Heo
2013-11-25 13:49 ` Alexander Gordeev
2013-10-18 17:12 ` [PATCH RFC v2 10/29] PCI/MSI: Get rid of pci_enable_msi_block_auto() interface Alexander Gordeev
2013-11-20 16:21 ` Tejun Heo
2013-10-18 17:12 ` [PATCH RFC v2 11/29] PCI/MSI: Convert pci_msix_table_size() to a public interface Alexander Gordeev
2013-11-20 16:23 ` Tejun Heo
2013-11-22 18:38 ` Alexander Gordeev
2013-10-18 17:12 ` [PATCH RFC v2 12/29] PCI/MSI: Introduce pcim_enable_msi*() family helpers Alexander Gordeev
2013-10-24 10:51 ` Tejun Heo
2013-10-24 10:57 ` David Laight
2013-10-24 11:01 ` Tejun Heo
2013-10-24 11:41 ` Alexander Gordeev
2013-10-25 2:22 ` Mark Lord
2013-10-25 9:10 ` David Laight
2013-10-25 10:01 ` Alexander Gordeev
2013-10-27 22:27 ` Michael Ellerman [this message]
2013-10-28 16:30 ` Mark Lord
2013-10-24 14:31 ` Alexander Gordeev
2013-10-25 2:23 ` Mark Lord
2013-11-04 8:12 ` Alexander Gordeev
2013-11-20 17:15 ` Tejun Heo
2013-11-22 18:44 ` Alexander Gordeev
2013-11-22 18:44 ` Tejun Heo
2013-11-22 18:54 ` Alexander Gordeev
2013-10-18 17:12 ` [PATCH RFC v2 13/29] ipr: Do not call pci_disable_msi/msix() if pci_enable_msi/msix() failed Alexander Gordeev
2013-10-18 17:12 ` [PATCH RFC v2 14/29] ipr: Make use of pcim_enable_msi/msix() interfaces Alexander Gordeev
2013-10-18 17:12 ` [PATCH RFC v2 15/29] ixgbe: Make use of pcim_enable_msix_range() interface Alexander Gordeev
2013-10-18 17:12 ` [PATCH RFC v2 16/29] ixgbevf: " Alexander Gordeev
2013-10-18 17:12 ` [PATCH RFC v2 17/29] megaraid: Make use of pcim_enable_msix() interface Alexander Gordeev
2013-10-18 17:12 ` [PATCH RFC v2 18/29] ntb: Fix missed call to pci_enable_msix() Alexander Gordeev
2013-10-18 17:12 ` [PATCH RFC v2 19/29] ntb: Make use of pcim_enable_msix/msix_exact() interfaces Alexander Gordeev
2013-10-18 17:12 ` [PATCH RFC v2 20/29] qib: Make use of pcim_enable_msix() and pci_msix_table_size() interfaces Alexander Gordeev
2013-10-18 17:12 ` [PATCH RFC v2 21/29] qla2xxx: Make use of pcim_enable_msix_range() interface Alexander Gordeev
2013-10-18 17:12 ` [PATCH RFC v2 22/29] qlge: Get rid of an redundant assignment Alexander Gordeev
2013-10-18 17:12 ` [PATCH RFC v2 23/29] qlge: Make use of pcim_enable_msix() interface Alexander Gordeev
2013-10-18 17:12 ` [PATCH RFC v2 24/29] tg3: " Alexander Gordeev
2013-10-18 17:12 ` [PATCH RFC v2 25/29] vmxnet3: Return -EINVAL if number of requested MSI-Xs is not enough Alexander Gordeev
2013-10-18 17:12 ` [PATCH RFC v2 26/29] vmxnet3: Fixup a weird loop exit Alexander Gordeev
2013-10-18 17:12 ` [PATCH RFC v2 27/29] vmxnet3: Return -ENOSPC when not enough MSI-X vectors available Alexander Gordeev
2013-10-18 17:12 ` [PATCH RFC v2 28/29] vmxnet3: Limit number of rx queues to 1 if per-queue MSI-Xs failed Alexander Gordeev
2013-10-18 17:12 ` [PATCH RFC v2 29/29] vmxnet3: Make use of pcim_enable_msix_range() interface Alexander Gordeev
2013-10-21 8:51 ` David Laight
2013-10-21 10:19 ` Alexander Gordeev
2013-11-11 19:56 ` [PATCH RFC v2 00/29] Introduce pcim_enable_msi*() family helpers Alexander Gordeev
2013-11-20 17:16 ` Tejun Heo
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1382912874.3371.9.camel@concordia \
--to=michael@ellerman.id.au \
--cc=David.Laight@ACULAB.COM \
--cc=agordeev@redhat.com \
--cc=benh@kernel.crashing.org \
--cc=bhelgaas@google.com \
--cc=bhutchings@solarflare.com \
--cc=hpa@zytor.com \
--cc=kernel@start.ca \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pci@vger.kernel.org \
--cc=tj@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox