netdev - [net-next 4/6] ixgbe: Reduce memory consumption with larger page sizes

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

Message-Id: <1383314210-24289-5-git-send-email-jeffrey.t.kirsher@intel.com>
Date:	Fri,  1 Nov 2013 06:56:48 -0700
From:	Jeff Kirsher <jeffrey.t.kirsher@...el.com>
To:	davem@...emloft.net
Cc:	Anton Blanchard <anton@...ba.org>, netdev@...r.kernel.org,
	gospo@...hat.com, sassmann@...hat.com,
	Jeff Kirsher <jeffrey.t.kirsher@...el.com>
Subject: [net-next 4/6] ixgbe: Reduce memory consumption with larger page sizes

From: Anton Blanchard <anton@...ba.org>

The ixgbe driver allocates pages for its receive rings. It currently
uses 512 pages, regardless of page size. During receive handling it
adds the unused part of the page back into the rx ring, avoiding the
need for a new allocation.

On a ppc64 box with 64 threads and 64kB pages, we end up with
512 entries * 64 rx queues * 64kB = 2GB memory used. Even more of a
concern is that we use up 2GB of IOMMU space in order to map all this
memory.

The driver makes a number of decisions based on if PAGE_SIZE is less
than 8kB, so use this as the breakpoint and only allocate 128 entries
on 8kB or larger page sizes.

Signed-off-by: Anton Blanchard <anton@...ba.org>
Tested-by: Phil Schmitt <phillip.j.schmitt@...el.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@...el.com>
---
 drivers/net/ethernet/intel/ixgbe/ixgbe.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe.h b/drivers/net/ethernet/intel/ixgbe/ixgbe.h
index f51fd1f..0914914 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe.h
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe.h
@@ -67,7 +67,11 @@
 #define IXGBE_MAX_TXD			   4096
 #define IXGBE_MIN_TXD			     64

+#if (PAGE_SIZE < 8192)
 #define IXGBE_DEFAULT_RXD		    512
+#else
+#define IXGBE_DEFAULT_RXD		    128
+#endif
 #define IXGBE_MAX_RXD			   4096
 #define IXGBE_MIN_RXD			     64

-- 
1.8.3.1

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html