btrace: honour scheduler-locking for all-stop targets

In all-stop mode, record btrace maintains the old behaviour of an implicit
scheduler-locking on.

Now that we added a scheduler-locking mode to model this old behaviour, we
don't need the respective code in record btrace anymore.  Remove it.

For all-stop targets, step inferior_ptid and continue other threads matching
the argument ptid.  Assert that inferior_ptid matches the argument ptid.

This should make record btrace honour scheduler-locking.

gdb/
	* record-btrace.c (record_btrace_resume): Honour scheduler-locking.

testsuite/
	* gdb.btrace/multi-thread-step.exp: Test scheduler-locking on, step,
	and replay.

2 files changed, 158 insertions, 74 deletions

diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index 23a957b..1b8e0e8 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,5 +1,10 @@
 2015-09-18  Markus Metzger  <markus.t.metzger@intel.com>
 
+	* gdb.btrace/multi-thread-step.exp: Test scheduler-locking on, step,
+	and replay.
+
+2015-09-18  Markus Metzger  <markus.t.metzger@intel.com>
+
 	* gdb.btrace/non-stop.c: New.
 	* gdb.btrace/non-stop.exp: New.
 
diff --git a/gdb/testsuite/gdb.btrace/multi-thread-step.exp b/gdb/testsuite/gdb.btrace/multi-thread-step.exp
index 2295f71..74748cc 100644
--- a/gdb/testsuite/gdb.btrace/multi-thread-step.exp
+++ b/gdb/testsuite/gdb.btrace/multi-thread-step.exp
@@ -37,9 +37,29 @@ set bp_2 [gdb_get_line_number "bp.2" $srcfile]
 set bp_3 [gdb_get_line_number "bp.3" $srcfile]
 
 proc gdb_cont_to_line { line } {
-	gdb_breakpoint $line
-	gdb_continue_to_breakpoint "cont to $line" ".*$line\r\n.*"
-	delete_breakpoints
+    gdb_breakpoint $line
+    gdb_continue_to_breakpoint "cont to $line" ".*$line\r\n.*"
+    delete_breakpoints
+}
+
+proc check_replay_insn { thread insn } {
+    gdb_test "thread apply $thread info record" \
+        "Replay in progress\.  At instruction $insn\."
+}
+
+proc check_not_replaying { thread } {
+    global gdb_prompt
+
+    set test "thread $thread not replaying"
+
+    gdb_test_multiple "thread apply $thread info record" $test {
+        -re "Replay in progress" {
+            fail $test
+        }
+        -re "$gdb_prompt $" {
+            pass $test
+        }
+    }
 }
 
 # trace the code between the two breakpoints
@@ -50,86 +70,145 @@ gdb_test "info threads" ".*"
 gdb_test_no_output "record btrace"
 gdb_cont_to_line $srcfile:$bp_2
 
-# navigate in the trace history for both threads
-with_test_prefix "navigate" {
-  gdb_test "thread 1" ".*"
-  with_test_prefix "thread 1" {
-    gdb_test "record goto begin" ".*"
-    gdb_test "info record" ".*Replay in progress\.  At instruction 1\."
-  }
-  gdb_test "thread 2" ".*"
-  with_test_prefix "thread 2" {
-    gdb_test "record goto begin" ".*"
-    gdb_test "info record" ".*Replay in progress\.  At instruction 1\."
-  }
+proc test_navigate {} {
+    with_test_prefix "navigate" {
+        gdb_test "thread 1" ".*"
+        with_test_prefix "thread 1" {
+            gdb_test "record goto begin" ".*"
+
+            check_replay_insn 1 1
+            check_not_replaying 2
+        }
+        gdb_test "thread 2" ".*"
+        with_test_prefix "thread 2" {
+            gdb_test "record goto begin" ".*"
+
+            check_replay_insn 1 1
+            check_replay_insn 2 1
+        }
+    }
 }
 
-# step both threads
-with_test_prefix "step" {
-  gdb_test "thread 1" ".*"
-  with_test_prefix "thread 1" {
-    gdb_test "info record" ".*Replay in progress\.  At instruction 1\."
-    gdb_test "stepi" ".*"
-    gdb_test "info record" ".*Replay in progress\.  At instruction 2\."
-  }
-  gdb_test "thread 2" ".*"
-  with_test_prefix "thread 2" {
-    gdb_test "info record" ".*Replay in progress\.  At instruction 1\."
-    gdb_test "stepi" ".*"
-    gdb_test "info record" ".*Replay in progress\.  At instruction 2\."
-  }
+proc test_step {} {
+    with_test_prefix "step" {
+        gdb_test "thread 1" ".*"
+        with_test_prefix "thread 1" {
+            gdb_test "stepi" ".*"
+
+            check_replay_insn 1 2
+            check_replay_insn 2 1
+        }
+        gdb_test "thread 2" ".*"
+        with_test_prefix "thread 2" {
+            gdb_test "stepi" ".*"
+
+            check_replay_insn 1 2
+            check_replay_insn 2 2
+        }
+    }
 }
 
-# run to the end of the history for both threads
-with_test_prefix "cont" {
-  gdb_test "thread 1" ".*"
-  with_test_prefix "thread 1" {
-    gdb_test "info record" ".*Replay in progress\.  At instruction 2\."
-    gdb_test "continue" "No more reverse-execution history.*"
-  }
-  gdb_test "thread 2" ".*"
-  with_test_prefix "thread 2" {
-    gdb_test "info record" ".*Replay in progress\.  At instruction 2\."
-    gdb_test "continue" "No more reverse-execution history.*"
-  }
+proc test_cont {} {
+    with_test_prefix "cont" {
+        gdb_test "thread 1" ".*"
+        with_test_prefix "thread 1" {
+            gdb_test "continue" "No more reverse-execution history.*"
+
+            check_not_replaying 1
+            check_replay_insn 2 2
+        }
+        gdb_test "thread 2" ".*"
+        with_test_prefix "thread 2" {
+            gdb_test "continue" "No more reverse-execution history.*"
+
+            check_not_replaying 1
+            check_not_replaying 2
+        }
+    }
 }
 
-# reverse-step both threads
-with_test_prefix "reverse-step" {
-  gdb_test "thread 1" ".*"
-  with_test_prefix "thread 1" {
-    gdb_test "reverse-stepi" ".*"
-    gdb_test "info record" ".*Replay in progress\..*"
-  }
-  gdb_test "thread 2" ".*"
-  with_test_prefix "thread 2" {
-    gdb_test "reverse-stepi" ".*"
-    gdb_test "info record" ".*Replay in progress\..*"
-  }
+proc test_cont_all {} {
+    with_test_prefix "cont-all" {
+        gdb_test "continue" "No more reverse-execution history.*"
+
+        # this works because we're lock-stepping threads that executed exactly
+        # the same code starting from the same instruction.
+
+        check_not_replaying 1
+        check_not_replaying 2
+    }
 }
 
-# both threads are still replaying
-with_test_prefix "check" {
-  gdb_test "thread 1" ".*"
-  with_test_prefix "thread 1" {
-    gdb_test "info record" ".*Replay in progress\..*"
-  }
-  gdb_test "thread 2" ".*"
-  with_test_prefix "thread 2" {
-    gdb_test "info record" ".*Replay in progress\..*"
-  }
+proc test_rstep {} {
+    with_test_prefix "reverse-step" {
+        gdb_test "thread apply all record goto 3"
+
+        gdb_test "thread 1" ".*"
+        with_test_prefix "thread 1" {
+            gdb_test "reverse-stepi" ".*"
+
+            check_replay_insn 1 2
+            check_replay_insn 2 3
+        }
+        gdb_test "thread 2" ".*"
+        with_test_prefix "thread 2" {
+            gdb_test "reverse-stepi" ".*"
+
+            check_replay_insn 1 2
+            check_replay_insn 2 2
+        }
+    }
+}
+
+proc test_goto_end {} {
+    with_test_prefix "goto-end" {
+        gdb_test "thread apply all record goto end"
+
+        check_not_replaying 1
+        check_not_replaying 2
+    }
+}
+
+foreach schedlock { "replay" "on" "step" } {
+    with_test_prefix "schedlock-$schedlock" {
+        gdb_test_no_output "set scheduler-locking $schedlock"
+
+        test_navigate
+        test_step
+        if { $schedlock == "step" } {
+            test_cont_all
+        } else {
+            test_cont
+        }
+        test_rstep
+        test_goto_end
+    }
 }
 
+# schedlock-off is difficult to test since we can't really say where the other
+# thread will be when the resumed thread stops.
+
 # navigate back into the history for thread 1 and continue thread 2
-with_test_prefix "cont" {
-  gdb_test "thread 1" ".*"
-  with_test_prefix "thread 1" {
-    gdb_test "record goto begin" ".*"
-    gdb_test "info record" ".*Replay in progress\.  At instruction 1\."
-  }
-  gdb_test "thread 2" ".*"
-  with_test_prefix "thread 2" {
-    gdb_test "record goto end" ".*"
-    gdb_cont_to_line $srcfile:$bp_3
-  }
+with_test_prefix "cont-to-end" {
+    # this test only works for scheduler-locking replay
+    gdb_test_no_output "set scheduler-locking replay"
+
+    gdb_test "thread 1" ".*"
+    with_test_prefix "thread 1" {
+        gdb_test "record goto begin" ".*"
+
+        check_replay_insn 1 1
+    }
+    gdb_test "thread 2" ".*"
+    with_test_prefix "thread 2" {
+        gdb_test "record goto end" ".*"
+
+        check_not_replaying 2
+
+        # if we reach the breakpoint, thread 2 terminated...
+        gdb_cont_to_line $srcfile:$bp_3
+
+        # and thread 1 stopped replaying
+        check_not_replaying 1
+    }
 }