1 files changed, 103 insertions, 0 deletions
diff --git a/testsuite/systemtap.base/maxactive.exp b/testsuite/systemtap.base/maxactive.exp
new file mode 100644
index 00000000..d5fdd0d2
--- /dev/null
+++ b/testsuite/systemtap.base/maxactive.exp
@@ -0,0 +1,103 @@
+# maxactive.exp
+#
+# Check to see if using the 'maxactive(N)' limit on return probes
+# works, by seeing if skipped probes increases when using it.
+
+if {[info procs installtest_p] != "" && ![installtest_p]} {
+    untested "MAXACTIVE"
+    return
+}
+
+# stap_run variant that sets 'skipped_probes' to the number of skipped
+# probes in a run.
+#
+# stap_run_skipped TEST_NAME
+# TEST_NAME is path to the current test
+# Additional arguments are passed to stap as-is.
+proc stap_run_skipped { TEST_NAME args } {
+    global skipped_probes
+
+    # initialize skipped_probes to 0
+    set skipped_probes 0
+
+    set cmd [concat {stap -v} $args]
+    eval spawn $cmd
+    expect {
+	-re {^Pass\ ([1234]):[^\r]*\ in\ ([0-9]+)usr/([0-9]+)sys/([0-9]+)real\ ms.\r\n}
+	{set pass$expect_out(1,string) "\t$expect_out(2,string)\t$expect_out(3,string)\t$expect_out(4,string)"; exp_continue}
+	-re {^Pass\ ([34]): using cached .+\r\n}
+	{set pass$expect_out(1,string) "\t0\t0\t0"; exp_continue}
+	-re {^Pass 5: starting run.\r\n} {exp_continue}
+	-timeout 30 -re "^systemtap starting probe\r\n" {
+	    pass "$TEST_NAME startup"
+
+	    # check the output to see if it is sane
+	    set output "^systemtap ending probe\r\n"
+
+	    expect {
+		-re $output {
+		    pass "$TEST_NAME shutdown and output"
+		    expect {
+			-re {^Pass\ ([5]):[^\r]*\ in\ ([0-9]+)usr/([0-9]+)sys/([0-9]+)real\ ms.\r\n}
+			{set pass$expect_out(1,string) "\t$expect_out(2,string)\t$expect_out(3,string)\t$expect_out(4,string)"
+			    verbose -log "metric:\t$TEST_NAME $pass1$pass2$pass3$pass4$pass5"}
+			-re {^WARNING: Number of errors: 0, skipped probes: ([0-9]+)\r\n}
+			{set skipped_probes $expect_out(1,string)}
+		    }
+		}
+		timeout { fail "$TEST_NAME shutdown (timeout)" }
+		eof { fail "$TEST_NAME shutdown (eof)" }
+	    }
+	}
+	-re "semantic error:" { fail "$TEST_NAME compilation" }
+	timeout { fail "$TEST_NAME startup (timeout)"; send "\003" }
+	eof { fail "$TEST_NAME startup (eof)" }
+    }
+  catch close
+  wait
+}
+
+# Script1.  For 5 seconds, probe the return of "sys_select" and
+# "sys_read".  See if we skip any probes.
+set script1 {
+    probe kernel.function("sys_select").return,
+        kernel.function("sys_read").return { }
+
+    probe timer.ms(5000) { exit(); }
+    probe begin { log("systemtap starting probe"); }
+    probe end { log("systemtap ending probe"); }
+}
+
+# Run script1 and save the number of skipped probes (which will most
+# likely be 0).
+stap_run_skipped "MAXACTIVE01" -e $script1
+set skipped1 $skipped_probes
+
+# Script2.  For 5 seconds, probe the return of "sys_select" and
+# "sys_read", with a limit of 1 probe active at a time.  See if we
+# skip any probes.
+set script2 {
+    probe kernel.function("sys_select").return.maxactive(1),
+        kernel.function("sys_read").return.maxactive(1) { }
+
+    probe timer.ms(5000) { exit(); }
+    probe begin { log("systemtap starting probe"); }
+    probe end { log("systemtap ending probe"); }
+}
+
+# Run script2 and save the number of skipped probes.
+stap_run_skipped "MAXACTIVE02" -e $script2
+set skipped2 $skipped_probes
+
+# If the number of skipped probes for script 1 is less than the number
+# of skipped probes for script 2, we can assume that "maxactive(N)" is
+# working.
+#
+# Note that this isn't 100% accurate based on the system load at the
+# time of the scripts.
+set TEST_NAME "MAXACTIVE03"
+if {$skipped1 < $skipped2} {
+    pass "$TEST_NAME ($skipped1 skipped probes < $skipped2 skipped probes)"
+} else {
+    fail "$TEST_NAME ($skipped1 skipped probes > $skipped2 skipped probes)"
+}