From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Garzik Subject: Re: [PATCH 1/5] ixgbe: Introduce MSI-X queue vector code Date: Wed, 05 Mar 2008 06:30:33 -0500 Message-ID: <47CE8459.6080006@garzik.org> References: <20080303230345.25151.48298.stgit@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: e1000-devel@lists.sourceforge.net, netdev@vger.kernel.org To: Auke Kok Return-path: In-Reply-To: <20080303230345.25151.48298.stgit@localhost.localdomain> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: e1000-devel-bounces@lists.sourceforge.net Errors-To: e1000-devel-bounces@lists.sourceforge.net List-Id: netdev.vger.kernel.org Auke Kok wrote: > From: Ayyappan Veeraiyan > > This code abstracts the per-queue MSI-X interrupt vector into > a queue vector layer. This abstraction is needed since there can > be many more queues than available MSI-X vectors in a machine. > > The MSI-X irq vectors are remapped to a shared queue vector which > can point to several (both RX and TX) hardware queues. The NAPI > algorithm then cleans the appropriate ring/queues on interrupt > or poll. > > The remapping is a delicate and complex calculation to make sure > that we're not unbalancing the irq load, and spreads the irqs > as much as possible, and may combine RX and TX flows onto the > same queue vector. > > This effectively enables receive flow hashing across vectors > and helps irq load balance across CPUs. > > Signed-off-by: Ayyappan Veeraiyan > Signed-off-by: Auke Kok > Acked-by: Jesse Brandeburg > Acked-by: Waskiewicz Jr, Peter P applied 1-5 to #upstream (2.6.26) ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/