commit 896c16c3b175d24b2247b37008bf61faebb6dee9 Author: David Goulet dgoulet@torproject.org Date: Tue Sep 28 22:27:51 2021 +0000

Add lttng trace support.

Signed-off-by: David Goulet dgoulet@torproject.org --- src/core/or/include.am | 3 + src/core/or/lttng_cc.inc | 166 ++++++++++++++++++++++++++++++++++++++++++ src/core/or/trace_probes_cc.c | 33 +++++++++ src/core/or/trace_probes_cc.h | 22 ++++++ 4 files changed, 224 insertions(+)

diff --git a/src/core/or/include.am b/src/core/or/include.am index d142062216..66529b70b2 100644 --- a/src/core/or/include.am +++ b/src/core/or/include.am @@ -82,6 +82,7 @@ noinst_HEADERS += \ src/core/or/entry_port_cfg_st.h \ src/core/or/extend_info_st.h \ src/core/or/listener_connection_st.h \ + src/core/or/lttng_cc.inc \ src/core/or/lttng_circuit.inc \ src/core/or/onion.h \ src/core/or/or.h \ @@ -115,7 +116,9 @@ noinst_HEADERS += \

if USE_TRACING_INSTRUMENTATION_LTTNG LIBTOR_APP_A_SOURCES += \ + src/core/or/trace_probes_cc.c \ src/core/or/trace_probes_circuit.c noinst_HEADERS += \ + src/core/or/trace_probes_cc.h \ src/core/or/trace_probes_circuit.h endif diff --git a/src/core/or/lttng_cc.inc b/src/core/or/lttng_cc.inc new file mode 100644 index 0000000000..b7bf58e196 --- /dev/null +++ b/src/core/or/lttng_cc.inc @@ -0,0 +1,166 @@ +/* Copyright (c) 2021, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * \file lttng_cc.inc + * \brief LTTng tracing probe declaration for the congestion control subsystem. + * It is in this .inc file due to the non C standard syntax and the way + * we guard the header with the LTTng specific + * TRACEPOINT_HEADER_MULTI_READ. + **/ + +#include "orconfig.h" + +/* We only build the following if LTTng instrumentation has been enabled. */ +#ifdef USE_TRACING_INSTRUMENTATION_LTTNG + +/* The following defines are LTTng-UST specific. */ +#undef TRACEPOINT_PROVIDER +#define TRACEPOINT_PROVIDER tor_cc + +#undef TRACEPOINT_INCLUDE +#define TRACEPOINT_INCLUDE "./src/core/or/lttng_cc.inc" + +#if !defined(LTTNG_CC_INC) || defined(TRACEPOINT_HEADER_MULTI_READ) +#define LTTNG_CC_INC + +#include <lttng/tracepoint.h> + +/* + * Flow Control + */ + +/* Emitted everytime the flow_control_decide_xon() function is called. */ +TRACEPOINT_EVENT(tor_cc, flow_decide_xon, + TP_ARGS(const edge_connection_t *, stream, size_t, n_written), + TP_FIELDS( + ctf_integer(uint64_t, stream_id, TO_CONN(stream)->global_identifier) + ctf_integer(size_t, written_bytes, n_written) + ctf_integer(uint32_t, drained_bytes_current, stream->drained_bytes) + ctf_integer(uint32_t, drained_bytes_previous, stream->prev_drained_bytes) + ctf_integer(uint32_t, ewma_drain_rate_last, stream->ewma_rate_last_sent) + ctf_integer(uint32_t, ewma_drain_rate_current, stream->ewma_drain_rate) + ctf_integer(size_t, outbuf_len, + connection_get_outbuf_len(TO_CONN(stream))) + ) +) + +/* Emitted when flow control starts measuring the drain rate. */ +TRACEPOINT_EVENT(tor_cc, flow_decide_xon_drain_start, + TP_ARGS(const edge_connection_t *, stream), + TP_FIELDS( + ctf_integer(uint64_t, stream_id, TO_CONN(stream)->global_identifier) + ctf_integer(uint32_t, drained_bytes_current, stream->drained_bytes) + ctf_integer(uint32_t, drained_bytes_previous, stream->prev_drained_bytes) + ctf_integer(uint32_t, ewma_drain_rate_last, stream->ewma_rate_last_sent) + ctf_integer(uint32_t, ewma_drain_rate_current, stream->ewma_drain_rate) + ctf_integer(size_t, outbuf_len, + connection_get_outbuf_len(TO_CONN(stream))) + ) +) + +/* Emitted when the drain rate is updated. The new_drain_rate value is what was + * just computed. */ +TRACEPOINT_EVENT(tor_cc, flow_decide_xon_drain_update, + TP_ARGS(const edge_connection_t *, stream, uint32_t, drain_rate), + TP_FIELDS( + ctf_integer(uint64_t, stream_id, TO_CONN(stream)->global_identifier) + ctf_integer(uint32_t, drained_bytes_current, stream->drained_bytes) + ctf_integer(uint32_t, drained_bytes_previous, stream->prev_drained_bytes) + ctf_integer(uint32_t, new_drain_rate, drain_rate) + ctf_integer(uint32_t, ewma_drain_rate_last, stream->ewma_rate_last_sent) + ctf_integer(uint32_t, ewma_drain_rate_current, stream->ewma_drain_rate) + ctf_integer(size_t, outbuf_len, + connection_get_outbuf_len(TO_CONN(stream))) + ) +) + +/* Emitted when an XON cell is sent due to a notice in a drain rate change. */ +TRACEPOINT_EVENT(tor_cc, flow_decide_xon_rate_change, + TP_ARGS(const edge_connection_t *, stream), + TP_FIELDS( + ctf_integer(uint64_t, stream_id, TO_CONN(stream)->global_identifier) + ctf_integer(uint32_t, drained_bytes_current, stream->drained_bytes) + ctf_integer(uint32_t, drained_bytes_previous, stream->prev_drained_bytes) + ctf_integer(uint32_t, ewma_drain_rate_last, stream->ewma_rate_last_sent) + ctf_integer(uint32_t, ewma_drain_rate_current, stream->ewma_drain_rate) + ctf_integer(size_t, outbuf_len, + connection_get_outbuf_len(TO_CONN(stream))) + ) +) + +/* Emitted when an XON cell is sent because we partially or fully drained the + * edge connection buffer. */ +TRACEPOINT_EVENT(tor_cc, flow_decide_xon_partial_drain, + TP_ARGS(const edge_connection_t *, stream), + TP_FIELDS( + ctf_integer(uint64_t, stream_id, TO_CONN(stream)->global_identifier) + ctf_integer(uint32_t, drained_bytes_current, stream->drained_bytes) + ctf_integer(uint32_t, drained_bytes_previous, stream->prev_drained_bytes) + ctf_integer(uint32_t, ewma_drain_rate_last, stream->ewma_rate_last_sent) + ctf_integer(uint32_t, ewma_drain_rate_current, stream->ewma_drain_rate) + ctf_integer(size_t, outbuf_len, + connection_get_outbuf_len(TO_CONN(stream))) + ) +) + +/* Emitted when we double the drain rate which is an attempt to see if we can + * speed things up. */ +TRACEPOINT_EVENT(tor_cc, flow_decide_xon_drain_doubled, + TP_ARGS(const edge_connection_t *, stream), + TP_FIELDS( + ctf_integer(uint64_t, stream_id, TO_CONN(stream)->global_identifier) + ctf_integer(uint32_t, drained_bytes_current, stream->drained_bytes) + ctf_integer(uint32_t, drained_bytes_previous, stream->prev_drained_bytes) + ctf_integer(uint32_t, ewma_drain_rate_last, stream->ewma_rate_last_sent) + ctf_integer(uint32_t, ewma_drain_rate_current, stream->ewma_drain_rate) + ctf_integer(size_t, outbuf_len, + connection_get_outbuf_len(TO_CONN(stream))) + ) +) + +/* XOFF */ + +/* Emitted when we send an XOFF cell. */ +TRACEPOINT_EVENT(tor_cc, flow_decide_xoff_sending, + TP_ARGS(const edge_connection_t *, stream), + TP_FIELDS( + ctf_integer(uint64_t, stream_id, TO_CONN(stream)->global_identifier) + ctf_integer(uint32_t, drained_bytes_current, stream->drained_bytes) + ctf_integer(uint32_t, drained_bytes_previous, stream->prev_drained_bytes) + ctf_integer(uint32_t, ewma_drain_rate_last, stream->ewma_rate_last_sent) + ctf_integer(uint32_t, ewma_drain_rate_current, stream->ewma_drain_rate) + ctf_integer(size_t, outbuf_len, + connection_get_outbuf_len(TO_CONN(stream))) + ) +) + +/* + * Congestion Control + */ + +/* Emitted when the BDP value has been updated. */ +TRACEPOINT_EVENT(tor_cc, bdp_update, + TP_ARGS(const circuit_t *, circ, const congestion_control_t *, cc, + uint64_t, curr_rtt_usec, uint64_t, sendme_rate_bdp), + TP_FIELDS( + ctf_integer(uint64_t, circuit_ptr, circ) + ctf_integer(uint32_t, n_circ_id, circ->n_circ_id) + ctf_integer(uint64_t, min_rtt_usec, cc->min_rtt_usec) + ctf_integer(uint64_t, curr_rtt_usec, curr_rtt_usec) + ctf_integer(uint64_t, ewma_rtt_usec, cc->ewma_rtt_usec) + ctf_integer(uint64_t, max_rtt_usec, cc->max_rtt_usec) + ctf_integer(uint64_t, bdp_inflight_rtt, cc->bdp[BDP_ALG_INFLIGHT_RTT]) + ctf_integer(uint64_t, bdp_cwnd_rtt, cc->bdp[BDP_ALG_CWND_RTT]) + ctf_integer(uint64_t, bdp_sendme_rate, cc->bdp[BDP_ALG_SENDME_RATE]) + ctf_integer(uint64_t, bdp_piecewise, cc->bdp[BDP_ALG_PIECEWISE]) + ctf_integer(uint64_t, sendme_rate_bdp, sendme_rate_bdp) + ) +) + +#endif /* LTTNG_CC_INC || TRACEPOINT_HEADER_MULTI_READ */ + +/* Must be included after the probes declaration. */ +#include <lttng/tracepoint-event.h> + +#endif /* USE_TRACING_INSTRUMENTATION_LTTNG */ diff --git a/src/core/or/trace_probes_cc.c b/src/core/or/trace_probes_cc.c new file mode 100644 index 0000000000..d52646da4f --- /dev/null +++ b/src/core/or/trace_probes_cc.c @@ -0,0 +1,33 @@ +/* Copyright (c) 2021, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * \file trace_probes_cc.c + * \brief Tracepoint provider source file for the cc subsystem. Probes + * are generated within this C file for LTTng-UST + **/ + +#include "orconfig.h" + +/* + * Following section is specific to LTTng-UST. + */ +#ifdef USE_TRACING_INSTRUMENTATION_LTTNG + +/* Header files that the probes need. */ +#include "core/or/or.h" +#include "core/or/channel.h" +#include "core/or/circuit_st.h" +#include "core/or/circuitlist.h" +#include "core/or/congestion_control_st.h" +#include "core/or/connection_st.h" +#include "core/or/edge_connection_st.h" +#include "core/or/or_circuit_st.h" +#include "core/or/origin_circuit_st.h" + +#define TRACEPOINT_DEFINE +#define TRACEPOINT_CREATE_PROBES + +#include "core/or/trace_probes_cc.h" + +#endif /* defined(USE_TRACING_INSTRUMENTATION_LTTNG) */ diff --git a/src/core/or/trace_probes_cc.h b/src/core/or/trace_probes_cc.h new file mode 100644 index 0000000000..1f87528723 --- /dev/null +++ b/src/core/or/trace_probes_cc.h @@ -0,0 +1,22 @@ +/* Copyright (c) 2021, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * \file trace_probes_cc.c + * \brief The tracing probes for the congestion control subsystem. + * Currently, only LTTng-UST probes are available. + **/ + +#ifndef TOR_TRACE_PROBES_CC_H +#define TOR_TRACE_PROBES_CC_H + +#include "lib/trace/events.h" + +/* We only build the following if LTTng instrumentation has been enabled. */ +#ifdef USE_TRACING_INSTRUMENTATION_LTTNG + +#include "core/or/lttng_cc.inc" + +#endif /* USE_TRACING_INSTRUMENTATION_LTTNG */ + +#endif /* !defined(TOR_TRACE_PROBES_CC_H) */