From: David Miller <davem@davemloft.net>
To: jeffrey.t.kirsher@intel.com
Cc: emil.s.tantilov@intel.com, netdev@vger.kernel.org,
gospo@redhat.com, sassmann@redhat.com, asharma@fb.com,
stable@vger.kernel.org, jacob.e.keller@intel.com
Subject: Re: [net-next 02/16] ixgbe: fix spinlock recursion with netpoll and busy poll
Date: Fri, 14 Mar 2014 14:58:50 -0400 (EDT) [thread overview]
Message-ID: <20140314.145850.706702494963811330.davem@davemloft.net> (raw)
In-Reply-To: <1394790446-31591-3-git-send-email-jeffrey.t.kirsher@intel.com>
From: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Date: Fri, 14 Mar 2014 02:47:12 -0700
> From: Emil Tantilov <emil.s.tantilov@intel.com>
>
> This patch resolves a hang with busy poll when used with netconsole.
>
> The main change is the check for netpoll packets in ixgbe_poll() which
> prevents a call to spin_lock_bh() while interrupts are disabled.
>
> In addition it removes the call to netif_rx() since netif_receive_skb()
> can deal with netpoll packets and also replaced the global adapter flag
> with per-q_vector bool that indicates Rx packet from netpoll which
> should help with performance.
>
> CC: Arun Sharma <asharma@fb.com>
> CC: stable <stable@vger.kernel.org>
> Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
> Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
> Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Eric Biederman and co. are working to make this completely unnecessary.
What is going to happen is that poll will be called with a budget of
zero, and no RX processing will thus occur, for netpoll.
Nothing in the RX path can handle being invoked from hardware
interrupt context, so we have to prevent it completely in all
drivers that support netpoll.
next prev parent reply other threads:[~2014-03-14 18:58 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-03-14 9:47 [net-next 00/16][pull request] Intel Wired LAN Driver Updates Jeff Kirsher
2014-03-14 9:47 ` [net-next 01/16] ixgbe: add check for netif_carrier_ok in ixgbe_xmit_frame Jeff Kirsher
2014-03-14 18:57 ` David Miller
2014-03-14 20:19 ` Tantilov, Emil S
2014-03-14 21:51 ` David Miller
2014-03-15 0:19 ` Ben Hutchings
2014-03-15 0:24 ` Tantilov, Emil S
2014-03-14 9:47 ` [net-next 02/16] ixgbe: fix spinlock recursion with netpoll and busy poll Jeff Kirsher
2014-03-14 18:58 ` David Miller [this message]
2014-03-14 20:40 ` Tantilov, Emil S
2014-03-14 21:53 ` David Miller
2014-03-15 2:08 ` Eric W. Biederman
2014-03-14 9:47 ` [net-next 03/16] igb: Fix code comment Jeff Kirsher
2014-03-14 9:47 ` [net-next 04/16] i40e: delete netdev after deleting napi and vectors Jeff Kirsher
2014-03-14 9:47 ` [net-next 05/16] i40e: Fix a bug in the update logic for FDIR SB filter Jeff Kirsher
2014-03-14 9:47 ` [net-next 06/16] i40e/i40evf: Some flow director HW definition fixes Jeff Kirsher
2014-03-14 9:47 ` [net-next 07/16] i40e: make string references to q be queue Jeff Kirsher
2014-03-14 9:47 ` [net-next 08/16] i40e: cleanup strings Jeff Kirsher
2014-03-14 9:47 ` [net-next 09/16] i40e: simplified init string Jeff Kirsher
2014-03-14 9:47 ` [net-next 10/16] i40e: Fix function comments Jeff Kirsher
2014-03-14 9:47 ` [net-next 11/16] i40e: Define a new state variable to keep track of feature auto disable Jeff Kirsher
2014-03-14 9:47 ` [net-next 12/16] i40e: Add code to handle FD table full condition Jeff Kirsher
2014-03-14 9:47 ` [net-next 13/16] i40e: Bug fix for FDIR replay logic Jeff Kirsher
2014-03-14 9:47 ` [net-next 14/16] i40e: Let MDD events be handled by MDD handler Jeff Kirsher
2014-03-14 9:47 ` [net-next 15/16] i40e/i40evf: Use correct number of VF vectors Jeff Kirsher
2014-03-14 9:47 ` [net-next 16/16] i40e/i40evf: Use dma_set_mask_and_coherent Jeff Kirsher
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