[PATCH 13/17] btrace: non-stop

[Markus Metzger <markus.t.metzger@intel.com>]

Support non-stop mode in record btrace.

2015-09-09  Markus Metzger <markus.t.metzger@intel.com>

gdb/
	* record-btrace.c (record_btrace_open): Remove non_stop check.
	* NEWS: Announce that record btrace supports non-stop mode.

testsuite/
	* gdb.btrace/non-stop.c: New.
	* gdb.btrace/non-stop.exp: New.
---
 gdb/NEWS                              |   2 +
 gdb/record-btrace.c                   |   3 -
 gdb/testsuite/gdb.btrace/non-stop.c   |  45 ++++++
 gdb/testsuite/gdb.btrace/non-stop.exp | 264 ++++++++++++++++++++++++++++++++++
 4 files changed, 311 insertions(+), 3 deletions(-)
 create mode 100644 gdb/testsuite/gdb.btrace/non-stop.c
 create mode 100644 gdb/testsuite/gdb.btrace/non-stop.exp

diff --git a/gdb/NEWS b/gdb/NEWS
index 0cf51e1..1fa1862 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -3,6 +3,8 @@
 
 *** Changes since GDB 7.10
 
+* Record btrace now supports non-stop mode.
+
 * Support for tracepoints on aarch64-linux was added in GDBserver.
 
 * The 'record instruction-history' command now indicates speculative execution
diff --git a/gdb/record-btrace.c b/gdb/record-btrace.c
index 119bf92..f3e6abe 100644
--- a/gdb/record-btrace.c
+++ b/gdb/record-btrace.c
@@ -216,9 +216,6 @@ record_btrace_open (const char *args, int from_tty)
   if (!target_has_execution)
     error (_("The program is not being run."));
 
-  if (non_stop)
-    error (_("Record btrace can't debug inferior in non-stop mode."));
-
   gdb_assert (record_btrace_thread_observer == NULL);
 
   disable_chain = make_cleanup (null_cleanup, NULL);
diff --git a/gdb/testsuite/gdb.btrace/non-stop.c b/gdb/testsuite/gdb.btrace/non-stop.c
new file mode 100644
index 0000000..2fc8dfb
--- /dev/null
+++ b/gdb/testsuite/gdb.btrace/non-stop.c
@@ -0,0 +1,45 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2015 Free Software Foundation, Inc.
+
+   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 <pthread.h>
+
+static int global;
+
+static void *
+test (void *arg)
+{
+  unsigned int i;
+
+  i = 0; /* bp.1 */
+  for (; i < 10; ++i) global += i; /* loop */
+
+  return arg; /* bp.2 */
+}
+
+int
+main (void)
+{
+  pthread_t th;
+
+  pthread_create (&th, NULL, test, NULL);
+
+  test (NULL);
+
+  pthread_join (th, NULL);
+
+  return 0; /* bp.3 */
+}
diff --git a/gdb/testsuite/gdb.btrace/non-stop.exp b/gdb/testsuite/gdb.btrace/non-stop.exp
new file mode 100644
index 0000000..ee7d1b6
--- /dev/null
+++ b/gdb/testsuite/gdb.btrace/non-stop.exp
@@ -0,0 +1,264 @@
+# This testcase is part of GDB, the GNU debugger.
+#
+# Copyright 2015 Free Software Foundation, Inc.
+#
+# 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/>.
+
+# check for btrace support
+if { [skip_btrace_tests] } { return -1 }
+
+
+# start inferior
+standard_testfile
+if {[gdb_compile_pthreads "$srcdir/$subdir/$srcfile" "$binfile" executable {debug}] != "" } {
+    return -1
+}
+clean_restart $testfile
+
+gdb_test_no_output "set non-stop on"
+
+if ![runto_main] {
+    return -1
+}
+
+# set up breakpoints
+set bp_1 [gdb_get_line_number "bp.1" $srcfile]
+set bp_2 [gdb_get_line_number "bp.2" $srcfile]
+set bp_3 [gdb_get_line_number "bp.3" $srcfile]
+
+gdb_breakpoint $bp_1
+gdb_breakpoint $bp_2
+
+# get the line number containing most of the trace
+set loop [gdb_get_line_number "loop" $srcfile]
+
+# a stop on the above line as reported by GDB
+set loop_line "$loop\[^\\\r\\\n\]*/\\\* loop \\\*/"
+
+# make sure $line matches the full expected output per thread.
+# and let's hope that GDB never mixes the output from different threads.
+#
+# this is quite fragile, mostly because the prompt appears somewhere in
+# the middle of the output.
+proc gdb_cont_to { threads cmd line nthreads } {
+    global gdb_prompt
+    set full_cmd "thread apply $threads $cmd"
+    set prompt_seen 0
+
+    send_gdb "$full_cmd\n"
+
+    for {set i 0} {$i < $nthreads} {incr i} {
+        set test "$full_cmd: thread $i"
+
+        # check for the prompt.  it may be in front of one of the lines we
+        # try to match.
+        gdb_test_multiple "" "$test: check prompt" {
+            -notransfer -re "$gdb_prompt " {
+                set prompt_seen 1
+            }
+        }
+
+        # check for the line.  and for a typical error.
+        gdb_test_multiple "" $test {
+            -re "Cannot execute this command \[^\\\r\\\n\]* is running\." {
+                fail $test
+            }
+            -re "$line\[^\\\r\\\n\]*\r\n" {
+                pass $test
+            }
+        }
+    }
+
+    # make sure we consume the prompt if we have not skipped it before.
+    if {$prompt_seen == 0} {
+        set test "$full_cmd: consume prompt"
+        gdb_test_multiple "" $test {
+            -re "$gdb_prompt " {
+                pass $test
+            }
+        }
+    }
+}
+
+proc gdb_cont_to_bp_line { line threads nthreads } {
+    gdb_cont_to $threads "continue" \
+        [multi_line \
+             "Breakpoint\[^\\\r\\\n\]*$line" \
+             "\[^\\\r\\\n\]*" \
+            ] \
+        $nthreads
+}
+
+proc gdb_cont_to_no_history { threads cmd nthreads } {
+    gdb_cont_to $threads $cmd \
+        [multi_line \
+             "No more reverse-execution history\." \
+             "\[^\\\r\\\n\]*" \
+             "\[^\\\r\\\n\]*" \
+            ] \
+        $nthreads
+}
+
+# trace the code between the two breakpoints
+gdb_cont_to_bp_line "$srcfile:$bp_1" all 2
+gdb_test_no_output "record btrace"
+gdb_cont_to_bp_line "$srcfile:$bp_2" all 2
+
+# we don't need those breakpoints any longer.
+# they will only disturb our stepping.
+delete_breakpoints
+
+# show the threads - this is useful for debugging fails
+gdb_test "thread apply all info rec" ".*"
+gdb_test "info threads" ".*"
+
+with_test_prefix "navigate" {
+    gdb_test "thread apply 1 record goto 2" "$loop_line"
+    gdb_test "thread apply 2 record goto 4" "$loop_line"
+    gdb_test "thread apply 1 info record" \
+        ".*Replay in progress\.  At instruction 2\."
+    gdb_test "thread apply 2 info record" \
+        ".*Replay in progress\.  At instruction 4\."
+
+    gdb_test "thread apply all record goto 5" "$loop_line"
+    gdb_test "thread apply 1 info record" \
+        ".*Replay in progress\.  At instruction 5\."
+    gdb_test "thread apply 2 info record" \
+        ".*Replay in progress\.  At instruction 5\."
+}
+
+with_test_prefix "step" {
+    with_test_prefix "thread 1" {
+        gdb_test "thread apply 1 stepi 2" "$loop_line"
+        gdb_test "thread apply 1 info record" \
+            ".*Replay in progress\.  At instruction 7\."
+        gdb_test "thread apply 2 info record" \
+            ".*Replay in progress\.  At instruction 5\."
+    }
+
+    with_test_prefix "thread 2" {
+        gdb_test "thread apply 2 stepi 3" "$loop_line"
+        gdb_test "thread apply 1 info record" \
+            ".*Replay in progress\.  At instruction 7\."
+        gdb_test "thread apply 2 info record" \
+            ".*Replay in progress\.  At instruction 8\."
+    }
+
+    with_test_prefix "all" {
+        gdb_cont_to all "stepi 4" "$loop_line" 2
+        gdb_test "thread apply 1 info record" \
+            ".*Replay in progress\.  At instruction 11\."
+        gdb_test "thread apply 2 info record" \
+            ".*Replay in progress\.  At instruction 12\."
+    }
+}
+
+with_test_prefix "reverse-step" {
+    with_test_prefix "thread 1" {
+        gdb_test "thread apply 1 reverse-stepi 2" "$loop_line"
+        gdb_test "thread apply 1 info record" \
+            ".*Replay in progress\.  At instruction 9\."
+        gdb_test "thread apply 2 info record" \
+            ".*Replay in progress\.  At instruction 12\."
+    }
+
+    with_test_prefix "thread 2" {
+        gdb_test "thread apply 2 reverse-stepi 3" "$loop_line"
+        gdb_test "thread apply 1 info record" \
+            ".*Replay in progress\.  At instruction 9\."
+        gdb_test "thread apply 2 info record" \
+            ".*Replay in progress\.  At instruction 9\."
+    }
+
+    with_test_prefix "all" {
+        gdb_cont_to all "reverse-stepi 4" "$loop_line" 2
+        gdb_test "thread apply 1 info record" \
+            ".*Replay in progress\.  At instruction 5\."
+        gdb_test "thread apply 2 info record" \
+            ".*Replay in progress\.  At instruction 5\."
+    }
+}
+
+with_test_prefix "continue" {
+    with_test_prefix "thread 1" {
+        gdb_cont_to_no_history 1 "continue" 1
+        gdb_test "thread apply 1 info record" \
+            ".*Recorded \[0-9\]+ instructions \[^\\\r\\\n\]*"
+        gdb_test "thread apply 2 info record" \
+            ".*Replay in progress\.  At instruction 5\."
+
+        gdb_cont_to_no_history 1 "reverse-continue" 1
+        gdb_test "thread apply 1 info record" \
+            ".*Replay in progress\.  At instruction 1\."
+        gdb_test "thread apply 2 info record" \
+            ".*Replay in progress\.  At instruction 5\."
+    }
+
+    with_test_prefix "thread 2" {
+        gdb_cont_to_no_history 2 "continue" 1
+        gdb_test "thread apply 1 info record" \
+            ".*Replay in progress\.  At instruction 1\."
+        gdb_test "thread apply 2 info record" \
+            ".*Recorded \[0-9\]+ instructions \[^\\\r\\\n\]*"
+
+        gdb_cont_to_no_history 2 "reverse-continue" 1
+        gdb_test "thread apply 1 info record" \
+            ".*Replay in progress\.  At instruction 1\."
+        gdb_test "thread apply 2 info record" \
+            ".*Replay in progress\.  At instruction 1\."
+    }
+}
+
+# a thread may only resume if no thread is still replaying
+with_test_prefix "no progress" {
+    with_test_prefix "thread 1" {
+        gdb_test "thread apply 1 record goto end" ".*"
+        gdb_test "thread apply 2 record goto begin" ".*"
+
+        gdb_cont_to_no_history 1 "continue" 1
+        gdb_cont_to_no_history 1 "step" 1
+        gdb_test "thread apply 1 info record" \
+            ".*Recorded \[0-9\]+ instructions \[^\\\r\\\n\]*"
+        gdb_test "thread apply 2 info record" \
+            ".*Replay in progress\.  At instruction 1\."
+    }
+
+    with_test_prefix "thread 2" {
+        gdb_test "thread apply 1 record goto begin" ".*"
+        gdb_test "thread apply 2 record goto end" ".*"
+
+        gdb_cont_to_no_history 2 "continue" 1
+        gdb_cont_to_no_history 2 "step" 1
+        gdb_test "thread apply 1 info record" \
+            ".*Replay in progress\.  At instruction 1\."
+        gdb_test "thread apply 2 info record" \
+            ".*Recorded \[0-9\]+ instructions \[^\\\r\\\n\]*"
+    }
+
+    with_test_prefix "all" {
+        gdb_test "thread apply all record goto begin" ".*"
+
+        gdb_cont_to_no_history all "continue" 2
+        gdb_test "thread apply 1 info record" \
+            ".*Recorded \[0-9\]+ instructions \[^\\\r\\\n\]*"
+        gdb_test "thread apply 2 info record" \
+            ".*Recorded \[0-9\]+ instructions \[^\\\r\\\n\]*"
+    }
+}
+
+# now that both threads stopped replaying we may resume recording
+with_test_prefix "cont to end" {
+    gdb_breakpoint $bp_3
+    gdb_cont_to_bp_line "$srcfile:$bp_3" all 1
+}
-- 
1.8.3.1