netdev - [PATCH net-next 2/3] bnx2x: save RAM in kdump kernel by using a single queue

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: <1393340666-3539-3-git-send-email-mschmidt@redhat.com>
Date:	Tue, 25 Feb 2014 16:04:25 +0100
From:	Michal Schmidt <mschmidt@...hat.com>
To:	davem@...emloft.net
Cc:	netdev@...r.kernel.org, ariele@...adcom.com, dmitry@...adcom.com,
	yuvalmin@...adcom.com
Subject: [PATCH net-next 2/3] bnx2x: save RAM in kdump kernel by using a single queue

When running in a kdump kernel, make sure to use only a single ethernet
queue even if a num_queues option in /etc/modprobe.d/*.conf would specify
otherwise. This saves memory, which tends to be scarce in kdump.

This saves about 40 MB in the kdump environment on a setup with
num_queues=8 in the config file.

Signed-off-by: Michal Schmidt <mschmidt@...hat.com>
---
 drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
index 64c17b6..500d38a 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
@@ -62,6 +62,11 @@ static void bnx2x_add_all_napi(struct bnx2x *bp)
 static int bnx2x_calc_num_queues(struct bnx2x *bp)
 {
 	int nq = bnx2x_num_queues ? : netif_get_num_default_rss_queues();
+
+	/* Reduce memory usage in kdump environment by using only one queue */
+	if (reset_devices)
+		nq = 1;
+
 	nq = clamp(nq, 1, BNX2X_MAX_QUEUES(bp));
 	return nq;
 }
-- 
1.8.5.3

--
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