alistair23-linux/include/uapi/linux/net_tstamp.h
Francis Yan 1c885808e4 tcp: SOF_TIMESTAMPING_OPT_STATS option for SO_TIMESTAMPING
This patch exports the sender chronograph stats via the socket
SO_TIMESTAMPING channel. Currently we can instrument how long a
particular application unit of data was queued in TCP by tracking
SOF_TIMESTAMPING_TX_SOFTWARE and SOF_TIMESTAMPING_TX_SCHED. Having
these sender chronograph stats exported simultaneously along with
these timestamps allow further breaking down the various sender
limitation.  For example, a video server can tell if a particular
chunk of video on a connection takes a long time to deliver because
TCP was experiencing small receive window. It is not possible to
tell before this patch without packet traces.

To prepare these stats, the user needs to set
SOF_TIMESTAMPING_OPT_STATS and SOF_TIMESTAMPING_OPT_TSONLY flags
while requesting other SOF_TIMESTAMPING TX timestamps. When the
timestamps are available in the error queue, the stats are returned
in a separate control message of type SCM_TIMESTAMPING_OPT_STATS,
in a list of TLVs (struct nlattr) of types: TCP_NLA_BUSY_TIME,
TCP_NLA_RWND_LIMITED, TCP_NLA_SNDBUF_LIMITED. Unit is microsecond.

Signed-off-by: Francis Yan <francisyyan@gmail.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-30 10:04:25 -05:00

131 lines
4 KiB
C

/*
* Userspace API for hardware time stamping of network packets
*
* Copyright (C) 2008,2009 Intel Corporation
* Author: Patrick Ohly <patrick.ohly@intel.com>
*
*/
#ifndef _NET_TIMESTAMPING_H
#define _NET_TIMESTAMPING_H
#include <linux/socket.h> /* for SO_TIMESTAMPING */
/* SO_TIMESTAMPING gets an integer bit field comprised of these values */
enum {
SOF_TIMESTAMPING_TX_HARDWARE = (1<<0),
SOF_TIMESTAMPING_TX_SOFTWARE = (1<<1),
SOF_TIMESTAMPING_RX_HARDWARE = (1<<2),
SOF_TIMESTAMPING_RX_SOFTWARE = (1<<3),
SOF_TIMESTAMPING_SOFTWARE = (1<<4),
SOF_TIMESTAMPING_SYS_HARDWARE = (1<<5),
SOF_TIMESTAMPING_RAW_HARDWARE = (1<<6),
SOF_TIMESTAMPING_OPT_ID = (1<<7),
SOF_TIMESTAMPING_TX_SCHED = (1<<8),
SOF_TIMESTAMPING_TX_ACK = (1<<9),
SOF_TIMESTAMPING_OPT_CMSG = (1<<10),
SOF_TIMESTAMPING_OPT_TSONLY = (1<<11),
SOF_TIMESTAMPING_OPT_STATS = (1<<12),
SOF_TIMESTAMPING_LAST = SOF_TIMESTAMPING_OPT_STATS,
SOF_TIMESTAMPING_MASK = (SOF_TIMESTAMPING_LAST - 1) |
SOF_TIMESTAMPING_LAST
};
/*
* SO_TIMESTAMPING flags are either for recording a packet timestamp or for
* reporting the timestamp to user space.
* Recording flags can be set both via socket options and control messages.
*/
#define SOF_TIMESTAMPING_TX_RECORD_MASK (SOF_TIMESTAMPING_TX_HARDWARE | \
SOF_TIMESTAMPING_TX_SOFTWARE | \
SOF_TIMESTAMPING_TX_SCHED | \
SOF_TIMESTAMPING_TX_ACK)
/**
* struct hwtstamp_config - %SIOCGHWTSTAMP and %SIOCSHWTSTAMP parameter
*
* @flags: no flags defined right now, must be zero for %SIOCSHWTSTAMP
* @tx_type: one of HWTSTAMP_TX_*
* @rx_filter: one of HWTSTAMP_FILTER_*
*
* %SIOCGHWTSTAMP and %SIOCSHWTSTAMP expect a &struct ifreq with a
* ifr_data pointer to this structure. For %SIOCSHWTSTAMP, if the
* driver or hardware does not support the requested @rx_filter value,
* the driver may use a more general filter mode. In this case
* @rx_filter will indicate the actual mode on return.
*/
struct hwtstamp_config {
int flags;
int tx_type;
int rx_filter;
};
/* possible values for hwtstamp_config->tx_type */
enum hwtstamp_tx_types {
/*
* No outgoing packet will need hardware time stamping;
* should a packet arrive which asks for it, no hardware
* time stamping will be done.
*/
HWTSTAMP_TX_OFF,
/*
* Enables hardware time stamping for outgoing packets;
* the sender of the packet decides which are to be
* time stamped by setting %SOF_TIMESTAMPING_TX_SOFTWARE
* before sending the packet.
*/
HWTSTAMP_TX_ON,
/*
* Enables time stamping for outgoing packets just as
* HWTSTAMP_TX_ON does, but also enables time stamp insertion
* directly into Sync packets. In this case, transmitted Sync
* packets will not received a time stamp via the socket error
* queue.
*/
HWTSTAMP_TX_ONESTEP_SYNC,
};
/* possible values for hwtstamp_config->rx_filter */
enum hwtstamp_rx_filters {
/* time stamp no incoming packet at all */
HWTSTAMP_FILTER_NONE,
/* time stamp any incoming packet */
HWTSTAMP_FILTER_ALL,
/* return value: time stamp all packets requested plus some others */
HWTSTAMP_FILTER_SOME,
/* PTP v1, UDP, any kind of event packet */
HWTSTAMP_FILTER_PTP_V1_L4_EVENT,
/* PTP v1, UDP, Sync packet */
HWTSTAMP_FILTER_PTP_V1_L4_SYNC,
/* PTP v1, UDP, Delay_req packet */
HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ,
/* PTP v2, UDP, any kind of event packet */
HWTSTAMP_FILTER_PTP_V2_L4_EVENT,
/* PTP v2, UDP, Sync packet */
HWTSTAMP_FILTER_PTP_V2_L4_SYNC,
/* PTP v2, UDP, Delay_req packet */
HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ,
/* 802.AS1, Ethernet, any kind of event packet */
HWTSTAMP_FILTER_PTP_V2_L2_EVENT,
/* 802.AS1, Ethernet, Sync packet */
HWTSTAMP_FILTER_PTP_V2_L2_SYNC,
/* 802.AS1, Ethernet, Delay_req packet */
HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ,
/* PTP v2/802.AS1, any layer, any kind of event packet */
HWTSTAMP_FILTER_PTP_V2_EVENT,
/* PTP v2/802.AS1, any layer, Sync packet */
HWTSTAMP_FILTER_PTP_V2_SYNC,
/* PTP v2/802.AS1, any layer, Delay_req packet */
HWTSTAMP_FILTER_PTP_V2_DELAY_REQ,
};
#endif /* _NET_TIMESTAMPING_H */