From patchwork Sat Apr 11 00:20:17 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Kirsher, Jeffrey T" X-Patchwork-Id: 460278 X-Patchwork-Delegate: jeffrey.t.kirsher@intel.com Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from whitealder.osuosl.org (whitealder.osuosl.org [140.211.166.138]) by ozlabs.org (Postfix) with ESMTP id 7A1611402F5 for ; Sat, 11 Apr 2015 10:20:42 +1000 (AEST) Received: from localhost (localhost [127.0.0.1]) by whitealder.osuosl.org (Postfix) with ESMTP id EC4328BD64; Sat, 11 Apr 2015 00:20:41 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from whitealder.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id eSOK2Qi3HnFg; Sat, 11 Apr 2015 00:20:40 +0000 (UTC) Received: from ash.osuosl.org (ash.osuosl.org [140.211.166.34]) by whitealder.osuosl.org (Postfix) with ESMTP id C41BB8BD42; Sat, 11 Apr 2015 00:20:40 +0000 (UTC) X-Original-To: intel-wired-lan@lists.osuosl.org Delivered-To: intel-wired-lan@lists.osuosl.org Received: from whitealder.osuosl.org (whitealder.osuosl.org [140.211.166.138]) by ash.osuosl.org (Postfix) with ESMTP id 86A561C22F4 for ; Sat, 11 Apr 2015 00:20:39 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by whitealder.osuosl.org (Postfix) with ESMTP id 80B2B8BD64 for ; Sat, 11 Apr 2015 00:20:39 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from whitealder.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id OLAFtr3pWy9R for ; Sat, 11 Apr 2015 00:20:38 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by whitealder.osuosl.org (Postfix) with ESMTP id C3DBA8BD32 for ; Sat, 11 Apr 2015 00:20:38 +0000 (UTC) Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by orsmga101.jf.intel.com with ESMTP; 10 Apr 2015 17:20:17 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.11,559,1422950400"; d="scan'208";a="479553119" Received: from bjhicke1-mobl.amr.corp.intel.com (HELO gmw-smvitp108.amr.corp.intel.com) ([10.254.74.251]) by FMSMGA003.fm.intel.com with ESMTP; 10 Apr 2015 17:20:18 -0700 From: Jeff Kirsher To: intel-wired-lan@lists.osuosl.org Date: Fri, 10 Apr 2015 17:20:17 -0700 Message-ID: <20150411001618.24651.38935.stgit@gmw-smvitp108.amr.corp.intel.com> User-Agent: StGit/0.17-dirty MIME-Version: 1.0 Subject: [Intel-wired-lan] [net-next v2 16/25] fm10k: don't handle mailbox events in iov_event path and always process mailbox X-BeenThere: intel-wired-lan@lists.osuosl.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: Intel Wired Ethernet Linux Kernel Driver Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-wired-lan-bounces@lists.osuosl.org Sender: "Intel-wired-lan" Since we already schedule the service task, we can just wait for this task to handle the mailbox events from the VF. This reduces some complex code flow, and makes it so we have a single path for handling the VF messages. There is a possibility that we have a slight delay in handling VF messages, but it should be minimal. The result of tx_complete and !rx_ready is insufficient to determine whether we need to process the mailbox. There is a possible race condition whereby the VF fills up the mbmem for us, but we have already recently processed the mailboxes in the interrupt. During this time, the interrupt is disabled. Thus, our Rx FIFO is empty, but the mbmem now has data in it. Since we continually check whether Rx FIFO is empty, we then never call process. This results in the possibility to prevent PF from handling the VF mailbox messages. Instead, just call process every time, despite the fact that we may or may not have anything to process for the VF. There should be minimal overhead for doing this, and it resolves an issue where the VF never comes up due to never getting response for its SET_LPORT_STATE message. Signed-off-by: Jeff Kirsher Signed-off-by: Jacob Keller Acked-by: Matthew Vick --- v2: on review, found that additional change was needed in the patch to resolve a possible race condition. --- drivers/net/ethernet/intel/fm10k/fm10k_iov.c | 34 ++------------------------ drivers/net/ethernet/intel/fm10k/fm10k_pci.c | 3 ++ 2 files changed, 5 insertions(+), 32 deletions(-) diff --git a/drivers/net/ethernet/intel/fm10k/fm10k_iov.c b/drivers/net/ethernet/intel/fm10k/fm10k_iov.c index 69cbfde..0b37e19 100644 --- a/drivers/net/ethernet/intel/fm10k/fm10k_iov.c +++ b/drivers/net/ethernet/intel/fm10k/fm10k_iov.c @@ -47,7 +47,7 @@ s32 fm10k_iov_event(struct fm10k_intfc *interface) { struct fm10k_hw *hw = &interface->hw; struct fm10k_iov_data *iov_data; - s64 mbicr, vflre; + s64 vflre; int i; /* if there is no iov_data then there is no mailboxes to process */ @@ -63,7 +63,7 @@ s32 fm10k_iov_event(struct fm10k_intfc *interface) goto read_unlock; if (!(fm10k_read_reg(hw, FM10K_EICR) & FM10K_EICR_VFLR)) - goto process_mbx; + goto read_unlock; /* read VFLRE to determine if any VFs have been reset */ do { @@ -86,32 +86,6 @@ s32 fm10k_iov_event(struct fm10k_intfc *interface) } } while (i != iov_data->num_vfs); -process_mbx: - /* read MBICR to determine which VFs require attention */ - mbicr = fm10k_read_reg(hw, FM10K_MBICR(1)); - mbicr <<= 32; - mbicr |= fm10k_read_reg(hw, FM10K_MBICR(0)); - - i = iov_data->next_vf_mbx ? : iov_data->num_vfs; - - for (mbicr <<= 64 - i; i--; mbicr += mbicr) { - struct fm10k_mbx_info *mbx = &iov_data->vf_info[i].mbx; - - if (mbicr >= 0) - continue; - - if (!hw->mbx.ops.tx_ready(&hw->mbx, FM10K_VFMBX_MSG_MTU)) - break; - - mbx->ops.process(hw, mbx); - } - - if (i >= 0) { - iov_data->next_vf_mbx = i + 1; - } else if (iov_data->next_vf_mbx) { - iov_data->next_vf_mbx = 0; - goto process_mbx; - } read_unlock: rcu_read_unlock(); @@ -155,10 +129,6 @@ process_mbx: mbx->ops.connect(hw, mbx); } - /* no work pending, then just continue */ - if (mbx->ops.tx_complete(mbx) && !mbx->ops.rx_ready(mbx)) - continue; - /* guarantee we have free space in the SM mailbox */ if (!hw->mbx.ops.tx_ready(&hw->mbx, FM10K_VFMBX_MSG_MTU)) break; diff --git a/drivers/net/ethernet/intel/fm10k/fm10k_pci.c b/drivers/net/ethernet/intel/fm10k/fm10k_pci.c index 64255cd..94c602f 100644 --- a/drivers/net/ethernet/intel/fm10k/fm10k_pci.c +++ b/drivers/net/ethernet/intel/fm10k/fm10k_pci.c @@ -984,6 +984,7 @@ static irqreturn_t fm10k_msix_mbx_pf(int __always_unused irq, void *data) /* service mailboxes */ if (fm10k_mbx_trylock(interface)) { mbx->ops.process(hw, mbx); + /* handle VFLRE events */ fm10k_iov_event(interface); fm10k_mbx_unlock(interface); } @@ -1000,6 +1001,8 @@ static irqreturn_t fm10k_msix_mbx_pf(int __always_unused irq, void *data) /* we should validate host state after interrupt event */ hw->mac.get_host_state = 1; + + /* validate host state, and handle VF mailboxes in the service task */ fm10k_service_event_schedule(interface); /* re-enable mailbox interrupt and indicate 20us delay */