dropmon: add ability to detect when hardware dropsrxpackets
Patch to add the ability to detect drops in hardware interfaces via dropwatch.
Adds a tracepoint to net_rx_action to signal everytime a napi instance is
polled. The dropmon code then periodically checks to see if the rx_frames
counter has changed, and if so, adds a drop notification to the netlink
protocol, using the reserved all-0's vector to indicate the drop location was in
hardware, rather than somewhere in the code.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
include/linux/net_dropmon.h | 8 ++
include/trace/napi.h | 11 +++
net/core/dev.c | 5 +
net/core/drop_monitor.c | 124 ++++++++++++++++++++++++++++++++++++++++++--
net/core/net-traces.c | 4 +
net/core/netpoll.c | 2
6 files changed, 149 insertions(+), 5 deletions(-)
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/net_dropmon.h b/include/linux/net_dropmon.h
index 0217fb8..e8a8b5c 100644
--- a/include/linux/net_dropmon.h
+++ b/include/linux/net_dropmon.h
@@ -2,12 +2,20 @@
#define __NET_DROPMON_H
#include <linux/netlink.h>
+#include <linux/types.h>
struct net_dm_drop_point {
__u8 pc[8];
__u32 count;
};
+#define is_drop_point_hw(x) do {\
+ int ____i, ____j;\
+ for (____i = 0; ____i < 8; i ____i++)\
+ ____j |= x[____i];\
+ ____j;\
+} while (0)
+
#define NET_DM_CFG_VERSION 0
#define NET_DM_CFG_ALERT_COUNT 1
#define NET_DM_CFG_ALERT_DELAY 2