[PATCH 3/5] async remote notification 'Trace'.

Yao Qi
2014-01-24T09:43:22Z

Hi,
This patch adds a new async remote notification 'Trace' to report the
trace-status-related changes in the stub. So far, it is only used for
reporting 'tracing status change', like this,

%Trace:status:T0;tstop::0;tframes:0;tcreated:0;tfree:500000;tsize:500000;circular:0;disconn:0;starttime:001355728912543287;stoptime:001355728912543768;username::;notes:666f6f:\n

V8:
GDBserver sends async notification Trace when tracing is started or
stopped, in order to keep the order of events correct in GDB side.

gdb/gdbserver:

* notif.c (notifs): Add "notif_trace".
* notif.h (ontif_trace): Declare.
* tracepoint.c [!IN_PROCESS_AGENT]: Include "notif.h".
[!IN_PROCESS_AGENT] (notif_reply_trace): New function.
[!IN_PROCESS_AGENT] (notif_trace): New variable.
(stop_tracing): Call notif_push.
(start_tracing): Call notif_push.

gdb:

* Makefile.in (REMOTE_OBS): Append remote-notif-trace.o
(SFILES): Add remote-notif-trace.c
* remote-notif.c (notifs): Add "notif_client_trace".
* remote-notif.h (notif_client_trace): Declare.
(REMOTE_NOTIF_TRACE): New enum
* remote-notif-trace.c: New.

gdb/doc:

* gdb.texinfo (Packets): Add "vTraced".
(Notification Packets): Add doc about "Trace" notification
and "vTraced" packet.
(General Query Packets): Document NotifTrace feature and reply of
qSupported.
---
gdb/Makefile.in | 5 ++-
gdb/doc/gdb.texinfo | 22 +++++++++++++
gdb/gdbserver/notif.c | 1 +
gdb/gdbserver/notif.h | 1 +
gdb/gdbserver/tracepoint.c | 35 ++++++++++++++++++++
gdb/remote-notif-trace.c | 76 ++++++++++++++++++++++++++++++++++++++++++++
gdb/remote-notif.c | 1 +
gdb/remote-notif.h | 2 +
8 files changed, 141 insertions(+), 2 deletions(-)
create mode 100644 gdb/remote-notif-trace.c

diff --git a/gdb/Makefile.in b/gdb/Makefile.in
index ed84e35..0978440 100644
--- a/gdb/Makefile.in
+++ b/gdb/Makefile.in
@@ -531,7 +531,7 @@ SER_HARDWIRE = @SER_HARDWIRE@
# The `remote' debugging target is supported for most architectures,
# but not all (e.g. 960)
REMOTE_OBS = remote.o dcache.o tracepoint.o ax-general.o ax-gdb.o remote-fileio.o \
- remote-notif.o ctf.o
+ remote-notif.o ctf.o remote-notif-trace.o

# This is remote-sim.o if a simulator is to be linked in.
SIM_OBS = @SIM_OBS@
@@ -762,7 +762,8 @@ SFILES = ada-exp.y ada-lang.c ada-typeprint.c ada-valprint.c ada-tasks.c \
p-exp.y p-lang.c p-typeprint.c p-valprint.c parse.c printcmd.c \
proc-service.list progspace.c \
prologue-value.c psymtab.c \
- regcache.c reggroups.c remote.c remote-fileio.c remote-notif.c reverse.c \
+ regcache.c reggroups.c remote.c remote-fileio.c remote-notif.c \
+ remote-notif-trace.c reverse.c \
sentinel-frame.c \
serial.c ser-base.c ser-unix.c skip.c \
solib.c solib-target.c source.c \
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index a990d2a..573bc83 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -38658,6 +38658,8 @@ for success (@pxref{Stop Reply Packets})

@item vStopped
@cindex @samp{vStopped} packet
+@itemx vTraced
+@cindex @samp{vTraced} packet
@xref{Notification Packets}.

@item X @var{addr},@var{length}:@var{XX@dots{}}
@@ -39491,6 +39493,10 @@ description.
This feature indicates whether @value{GDBN} supports the
@samp{qRelocInsn} packet (@pxref{Tracepoint Packets,,Relocate
instruction reply packet}).
+
+@item NotifTrace
+This feature indicates that @value{GDBN} supports the async remote
+notification trace (@pxref{Notification Packets}).
@end table

Stubs should ignore any unknown values for
@@ -39709,6 +39715,11 @@ These are the currently defined stub features and their properties:
@tab @samp{-}
@tab No

+@item @samp{NotifTrace}
+@tab No
+@tab @samp{-}
+@tab No
+
@end multitable

These are the currently defined stub features, in more detail:
@@ -39876,6 +39887,10 @@ See @ref{Bytecode Descriptions} for details about the bytecode.
The remote stub supports running a breakpoint's command list itself,
rather than reporting the hit to @value{GDBN}.

+@item NotifTrace
+@cindex async notification trace, in remote protocol
+The remote stub supports the async notification trace.
+
@item Qbtrace:off
The remote stub understands the @samp{Qbtrace:off} packet.

@@ -40668,6 +40683,7 @@ continue the tracing run, while 0 tells the target to stop tracing if
@value{GDBN} is no longer in the picture.

@item qTStatus
+@anchor{qTStatus packet}
@cindex @samp{qTStatus} packet
Ask the stub if there is a trace experiment running right now.

@@ -41198,6 +41214,12 @@ for information on how these notifications are acknowledged by
@value{GDBN}.
@tab Report an asynchronous stop event in non-stop mode.

+@item Trace
+@tab vTraced
+@tab @var{status}. The @var{reply} has the form of the reply to
+packet @samp{qTStatus}, as described in @ref{qTStatus packet}.
+@tab Report an asynchronous event related to trace status.
+
@end multitable

@node Remote Non-Stop
diff --git a/gdb/gdbserver/notif.c b/gdb/gdbserver/notif.c
index 3847110..437a9d0 100644
--- a/gdb/gdbserver/notif.c
+++ b/gdb/gdbserver/notif.c
@@ -52,6 +52,7 @@
static struct notif_server *notifs[] =
{
&notif_stop,
+ &notif_trace,
};

/* Write another event or an OK, if there are no more left, to
diff --git a/gdb/gdbserver/notif.h b/gdb/gdbserver/notif.h
index 671ef32..2934d97 100644
--- a/gdb/gdbserver/notif.h
+++ b/gdb/gdbserver/notif.h
@@ -58,6 +58,7 @@ typedef struct notif_server
} *notif_server_p;

extern struct notif_server notif_stop;
+extern struct notif_server notif_trace;

int handle_notif_ack (char *own_buf, int packet_len);
void notif_write_event (struct notif_server *notif, char *own_buf);
diff --git a/gdb/gdbserver/tracepoint.c b/gdb/gdbserver/tracepoint.c
index 3706577..22f88d9 100644
--- a/gdb/gdbserver/tracepoint.c
+++ b/gdb/gdbserver/tracepoint.c
@@ -3201,6 +3201,25 @@ install_tracepoint (struct tracepoint *tpoint, char *own_buf)
write_ok (own_buf);
}

+#ifndef IN_PROCESS_AGENT
+#include "notif.h"
+
+static void cmd_qtstatus (char *packet);
+
+static void
+notif_reply_trace (struct notif_event *event, char *own_buf)
+{
+ sprintf (own_buf, "status:");
+ cmd_qtstatus (own_buf + 7);
+}
+
+struct notif_server notif_trace =
+{
+ "vTraced", "Trace", NULL, notif_reply_trace, 0,
+};
+
+#endif
+
static void download_tracepoint_1 (struct tracepoint *tpoint);

static void
@@ -3394,6 +3413,14 @@ cmd_qtstart (char *packet)
unpause_all (1);

write_ok (packet);
+
+ if (notif_trace.supported)
+ {
+ struct notif_event *event
+ = xmalloc (sizeof (struct notif_event));
+
+ notif_push (&notif_trace, event);
+ }
}

/* End a tracing run, filling in a stop reason to report back to GDB,
@@ -3496,6 +3523,14 @@ stop_tracing (void)
}

unpause_all (1);
+
+ if (notif_trace.supported)
+ {
+ struct notif_event *event
+ = xmalloc (sizeof (struct notif_event));
+
+ notif_push (&notif_trace, event);
+ }
}

static int
diff --git a/gdb/remote-notif-trace.c b/gdb/remote-notif-trace.c
new file mode 100644
index 0000000..9ae1d33
--- /dev/null
+++ b/gdb/remote-notif-trace.c
@@ -0,0 +1,76 @@
+/* Async remote notification on trace.
+
+ Copyright (C) 2014 Free Software Foundation, Inc.
+
+ This file is part of GDB.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
+
+#include "defs.h"
+#include <string.h>
+#include "remote.h"
+#include "tracepoint.h"
+#include "remote-notif.h"
+
+static void
+remote_notif_trace_parse (struct notif_client *self, char *buf,
+ struct notif_event *event)
+{
+ if (strncmp (buf, "status:", 7) == 0)
+ {
+ struct trace_status *ts = current_trace_status ();
+
+ if (buf[7] != 'T')
+ error (_("Unknown trace status in trace notification."));
+ parse_trace_status (buf + 7 + 1, ts);
+ }
+ else
+ error (_("Unknown trace notification."));
+}
+
+static void
+remote_notif_trace_ack (struct notif_client *self, char *buf,
+ struct notif_event *event)
+{
+ /* acknowledge */
+ putpkt ((char *) self->ack_command);
+}
+
+static int
+remote_notif_trace_can_get_pending_events (struct notif_client *self)
+{
+ return 1;
+}
+
+static struct notif_event *
+remote_notif_trace_alloc_event (void)
+{
+ struct notif_event *event = xmalloc (sizeof (struct notif_event));
+
+ event->dtr = NULL;
+
+ return event;
+}
+
+/* A client of notification 'Trace'. */
+
+struct notif_client notif_client_trace =
+{
+ "Trace", "vTraced",
+ remote_notif_trace_parse,
+ remote_notif_trace_ack,
+ remote_notif_trace_can_get_pending_events,
+ remote_notif_trace_alloc_event,
+ REMOTE_NOTIF_TRACE,
+};
diff --git a/gdb/remote-notif.c b/gdb/remote-notif.c
index ee2c2c4..8672696 100644
--- a/gdb/remote-notif.c
+++ b/gdb/remote-notif.c
@@ -49,6 +49,7 @@ int notif_debug = 0;
static struct notif_client *notifs[] =
{
&notif_client_stop,
+ &notif_client_trace,
};

gdb_static_assert (ARRAY_SIZE (notifs) == REMOTE_NOTIF_LAST);
diff --git a/gdb/remote-notif.h b/gdb/remote-notif.h
index 6fd58bf..1b55aab 100644
--- a/gdb/remote-notif.h
+++ b/gdb/remote-notif.h
@@ -36,6 +36,7 @@ struct notif_event
enum REMOTE_NOTIF_ID
{
REMOTE_NOTIF_STOP = 0,
+ REMOTE_NOTIF_TRACE,
REMOTE_NOTIF_LAST,
};

@@ -123,6 +124,7 @@ struct notif_client *remote_notif_find (const char *name);
char *remote_notif_qsupported (char *buf);

extern struct notif_client notif_client_stop;
+extern struct notif_client notif_client_trace;

extern int notif_debug;

--
1.7.7.6