linux-kernel - [PATCH] ixgbe: take online CPU number as MQ max limit when alloc_etherdev

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <1463118995-31763-1-git-send-email-ethan.zhao@oracle.com>
Date:	Fri, 13 May 2016 14:56:35 +0900
From:	Ethan Zhao <ethan.zhao@...cle.com>
To:	jeffrey.t.kirsher@...el.com, jesse.brandeburg@...el.com,
	shannon.nelson@...el.com, carolyn.wyborny@...el.com,
	donald.c.skidmore@...el.com, bruce.w.allan@...el.com,
	john.ronciak@...el.com, mitch.a.williams@...el.com,
	intel-wired-lan@...ts.osuosl.org, netdev@...r.kernel.org
Cc:	linux-kernel@...r.kernel.org, ethan.kernel@...il.com,
	ethan.zhao@...cle.com
Subject: [PATCH] ixgbe: take online CPU number as MQ max limit when  alloc_etherdev_mq()

Allocating 64 Tx/Rx as default doesn't benefit perfomrnace when less
CPUs were assigned. especially when DCB is enabled, so we should take
num_online_cpus() as top limit, and aslo to make sure every TC has
at least one queue, take the MAX_TRAFFIC_CLASS as bottom limit of queues
number.

Signed-off-by: Ethan Zhao <ethan.zhao@...cle.com>
---
 drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index 7df3fe2..1f9769c 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -9105,6 +9105,10 @@ static int ixgbe_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 		indices = IXGBE_MAX_RSS_INDICES;
 #endif
 	}
+	/* Don't allocate too more queues than online cpus number */
+	indices = min_t(int, indices, num_online_cpus());
+	/* To make sure TC works, allocate at least 1 queue per TC */
+	indices = max_t(int, indices, MAX_TRAFFIC_CLASS);
 
 	netdev = alloc_etherdev_mq(sizeof(struct ixgbe_adapter), indices);
 	if (!netdev) {
-- 
1.8.3.1