From 29e2616aeeb82605a6efe1dbc574b499781eafbe Mon Sep 17 00:00:00 2001
From: Josh Stone <jistone@redhat.com>
Date: Wed, 20 May 2009 14:46:25 -0700
Subject: PR10177: init/kill time in sleepy context only

Previously, _stp_init_time and _stp_kill_time were being called from
begin/end/error probes, which will run with preemption disabled.  The
BUG reported on RT kernels showed that cpufreq_unregister_notifier can
end up sleeping, which violates our preemption block.

This patch moves the init/kill into systemtap_module_init/exit, where it
is safe to sleep.  The code maintains a new predicate with the define
STAP_NEED_GETTIMEOFDAY, so we don't still incur any timer overhead if
it's not used.
---
 testsuite/buildok/gtod_init.stp | 13 +++++++++++++
 1 file changed, 13 insertions(+)
 create mode 100755 testsuite/buildok/gtod_init.stp

(limited to 'testsuite/buildok/gtod_init.stp')

diff --git a/testsuite/buildok/gtod_init.stp b/testsuite/buildok/gtod_init.stp
new file mode 100755
index 00000000..1d76aeab
--- /dev/null
+++ b/testsuite/buildok/gtod_init.stp
@@ -0,0 +1,13 @@
+#! stap -gp4
+
+# check that STAP_NEED_GETTIMEOFDAY is defined with a gettimeofday
+function check() %{
+#ifndef STAP_NEED_GETTIMEOFDAY
+#error "gettimeofday should define STAP_NEED_GETTIMEOFDAY!"
+#endif
+%}
+
+probe begin {
+    check()
+    println(gettimeofday_s())
+}
-- 
cgit