From patchwork Tue Feb 4 17:52:39 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tony Nguyen X-Patchwork-Id: 13959538 X-Patchwork-Delegate: kuba@kernel.org Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.16]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 548542165E0 for ; Tue, 4 Feb 2025 17:52:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.16 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738691578; cv=none; b=eekFE5Igt7e4BjIKuT+2BJyZAn5NGnG6Z5wpBCv7QksGZgWMI9l5slrcFRdvR6zaI44qahALC6RC3zPueiE1a3of0uLcwJA0YBaBFwOxD18xqk75ksX4jPICwvusSySal9V9D8PG6P4KmM9KEhruQtGjixM60YJ0YxIGbpJ7Nh8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738691578; c=relaxed/simple; bh=FYdWzTpcxPkf0D2vrnuywRxJdpODKh0DW9jB4ZCwYoY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=tnPRST8Toh6S2AdoGd8T2AqLNQH7WbBKvb8FFqv/4PV8KduST3i5yZZ/MdYV1IsJbdiiOxGW6yPz9JB9x04V7tRY1nXb7aPwk0s+Fxb+OzO70iaEKzVoiWJ+fb0ukh9xXs3GKWMDrUHrGbL6vZPDQRd06AWkwajfdNFHB6tbvf0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=GQJ1HVjM; arc=none smtp.client-ip=198.175.65.16 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="GQJ1HVjM" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1738691577; x=1770227577; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=FYdWzTpcxPkf0D2vrnuywRxJdpODKh0DW9jB4ZCwYoY=; b=GQJ1HVjM5IKxgVrSFCrqg1SSqnsZB0zSlSQu/b4GlN2u1dJzQG4xTdDm 696LJVOSu19qtH7sb12G04qhr8jx28hnRSnVoQKk0yWRcZ9S5yqi2UyBV MA8JVmu+InHjhzdMVGyDU9JlHWCEL2dzlcutHT/RlS2p6luc6CI7Ynk4C mUD4obFSkNMrfDy8TBOX6FDSe2hpjnu6BF12HwpGUtRWUjgYnV6Vw7XCB CtBWfRfUfiJXz+SqGrNUjh720nHV9mzy+298sfKaC0x5inHAzZUeykzqv DJCNJQIzvIe6SD+rNgHSPBD8YJLpavvCkhBGtHxdJK+aReYrDuo7M6O4c Q==; X-CSE-ConnectionGUID: P54LWji2QauNo8bfcrFodQ== X-CSE-MsgGUID: g2s8Nc5cRdekB7qqztlHBQ== X-IronPort-AV: E=McAfee;i="6700,10204,11336"; a="39371896" X-IronPort-AV: E=Sophos;i="6.13,259,1732608000"; d="scan'208";a="39371896" Received: from orviesa006.jf.intel.com ([10.64.159.146]) by orvoesa108.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 Feb 2025 09:52:54 -0800 X-CSE-ConnectionGUID: 3W+/JMlsRw+s2Dj99EDLPQ== X-CSE-MsgGUID: 2IRSlQ1hSWGEeO+Ja6xtuw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.13,259,1732608000"; d="scan'208";a="110652396" Received: from anguy11-upstream.jf.intel.com ([10.166.9.133]) by orviesa006.jf.intel.com with ESMTP; 04 Feb 2025 09:52:53 -0800 From: Tony Nguyen To: davem@davemloft.net, kuba@kernel.org, pabeni@redhat.com, edumazet@google.com, andrew+netdev@lunn.ch, netdev@vger.kernel.org Cc: Wander Lairson Costa , anthony.l.nguyen@intel.com, rostedt@goodmis.org, clrkwllms@kernel.org, bigeasy@linutronix.de, jgarzik@redhat.com, yuma@redhat.com, linux-rt-devel@lists.linux.dev, Rafal Romanowski Subject: [PATCH net 3/4] igb: split igb_msg_task() Date: Tue, 4 Feb 2025 09:52:39 -0800 Message-ID: <20250204175243.810189-4-anthony.l.nguyen@intel.com> X-Mailer: git-send-email 2.47.1 In-Reply-To: <20250204175243.810189-1-anthony.l.nguyen@intel.com> References: <20250204175243.810189-1-anthony.l.nguyen@intel.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: kuba@kernel.org From: Wander Lairson Costa From the perspective of PREEMPT_RT, igb_msg_task() invokes functions that are a mix of IRQ-safe and non-IRQ-safe operations. To address this, we separate igb_msg_task() into distinct IRQ-safe and preemptible-safe components. This is a preparatory step for upcoming commits, where the igb_msix_other interrupt handler will be split into IRQ and threaded handlers, each invoking the appropriate part of the newly divided igb_msg_task(). Signed-off-by: Wander Lairson Costa Tested-by: Rafal Romanowski Signed-off-by: Tony Nguyen --- drivers/net/ethernet/intel/igb/igb_main.c | 88 +++++++++++++++++++++-- 1 file changed, 81 insertions(+), 7 deletions(-) diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c index 4e75c88f6214..6d590192c27f 100644 --- a/drivers/net/ethernet/intel/igb/igb_main.c +++ b/drivers/net/ethernet/intel/igb/igb_main.c @@ -146,6 +146,8 @@ static int igb_vlan_rx_kill_vid(struct net_device *, __be16, u16); static void igb_restore_vlan(struct igb_adapter *); static void igb_rar_set_index(struct igb_adapter *, u32); static void igb_ping_all_vfs(struct igb_adapter *); +static void igb_msg_task_irq_safe(struct igb_adapter *adapter); +static void igb_msg_task_preemptible_safe(struct igb_adapter *adapter); static void igb_msg_task(struct igb_adapter *); static void igb_vmm_control(struct igb_adapter *); static int igb_set_vf_mac(struct igb_adapter *, int, unsigned char *); @@ -3681,6 +3683,30 @@ static __always_inline void vfs_unlock_irqrestore(struct igb_adapter *adapter, raw_spin_unlock_irqrestore(&adapter->raw_vfs_lock, flags); spin_unlock_irqrestore(&adapter->vfs_lock, flags); } + +static __always_inline void vfs_spin_lock_irqsave(struct igb_adapter *adapter, + unsigned long *flags) +{ + spin_lock_irqsave(&adapter->vfs_lock, *flags); +} + +static __always_inline void vfs_spin_unlock_irqrestore(struct igb_adapter *adapter, + unsigned long flags) +{ + spin_unlock_irqrestore(&adapter->vfs_lock, flags); +} + +static __always_inline void vfs_raw_spin_lock_irqsave(struct igb_adapter *adapter, + unsigned long *flags) +{ + raw_spin_lock_irqsave(&adapter->raw_vfs_lock, *flags); +} + +static __always_inline void vfs_raw_spin_unlock_irqrestore(struct igb_adapter *adapter, + unsigned long flags) +{ + raw_spin_unlock_irqrestore(&adapter->raw_vfs_lock, flags); +} #else static __always_inline void vfs_lock_init(struct igb_adapter *adapter) { @@ -3696,6 +3722,30 @@ static __always_inline void vfs_unlock_irqrestore(struct igb_adapter *adapter, u { spin_unlock_irqrestore(&adapter->vfs_lock, flags); } + +static __always_inline void vfs_spin_lock_irqsave(struct igb_adapter *adapter, + unsigned long *flags) +{ + spin_lock_irqsave(&adapter->vfs_lock, *flags); +} + +static __always_inline void vfs_spin_unlock_irqrestore(struct igb_adapter *adapter, + unsigned long flags) +{ + spin_unlock_irqrestore(&adapter->vfs_lock, flags); +} + +static __always_inline void vfs_raw_spin_lock_irqsave(struct igb_adapter *adapter, + unsigned long *flags) +{ + spin_lock_irqsave(&adapter->vfs_lock, *flags); +} + +static __always_inline void vfs_raw_spin_unlock_irqrestore(struct igb_adapter *adapter, + unsigned long flags) +{ + spin_unlock_irqrestore(&adapter->vfs_lock, flags); +} #endif #ifdef CONFIG_PCI_IOV @@ -8113,27 +8163,51 @@ static void igb_rcv_msg_from_vf(struct igb_adapter *adapter, u32 vf) igb_unlock_mbx(hw, vf); } -static void igb_msg_task(struct igb_adapter *adapter) +/* + * Note: the split of irq and preempible safe parts of igb_msg_task() + * only makes sense under PREEMPT_RT. + * The root cause of igb_rcv_msg_from_vf() is not IRQ safe is because + * it calls kcalloc with GFP_ATOMIC, but GFP_ATOMIC is not IRQ safe + * in PREEMPT_RT. + */ +static void igb_msg_task_irq_safe(struct igb_adapter *adapter) { struct e1000_hw *hw = &adapter->hw; unsigned long flags; u32 vf; - vfs_lock_irqsave(adapter, &flags); + vfs_raw_spin_lock_irqsave(adapter, &flags); for (vf = 0; vf < adapter->vfs_allocated_count; vf++) { /* process any reset requests */ if (!igb_check_for_rst(hw, vf)) igb_vf_reset_event(adapter, vf); - /* process any messages pending */ - if (!igb_check_for_msg(hw, vf)) - igb_rcv_msg_from_vf(adapter, vf); - /* process any acks */ if (!igb_check_for_ack(hw, vf)) igb_rcv_ack_from_vf(adapter, vf); } - vfs_unlock_irqrestore(adapter, flags); + vfs_raw_spin_unlock_irqrestore(adapter, flags); +} + +static void igb_msg_task_preemptible_safe(struct igb_adapter *adapter) +{ + struct e1000_hw *hw = &adapter->hw; + unsigned long flags; + u32 vf; + + vfs_spin_lock_irqsave(adapter, &flags); + for (vf = 0; vf < adapter->vfs_allocated_count; vf++) { + /* process any messages pending */ + if (!igb_check_for_msg(hw, vf)) + igb_rcv_msg_from_vf(adapter, vf); + } + vfs_spin_unlock_irqrestore(adapter, flags); +} + +static __always_inline void igb_msg_task(struct igb_adapter *adapter) +{ + igb_msg_task_irq_safe(adapter); + igb_msg_task_preemptible_safe(adapter); } /**