Support signalfd4 in syscalls2.stp tapset.

* tapset/aux_syscalls.stp (_signalfd4_flags_str): New utility function.
* tapset/syscalls2.stp (syscall.signalfd[.return]): Handle signalfd4 variant
  when available.
* testsuite/systemtap.syscall/signalfd.c: New test.

3 files changed, 75 insertions, 5 deletions

diff --git a/tapset/aux_syscalls.stp b/tapset/aux_syscalls.stp
index 6179719c..bd62817d 100644
--- a/tapset/aux_syscalls.stp
+++ b/tapset/aux_syscalls.stp
@@ -1685,6 +1685,29 @@ function _eventfd2_flag_str:string(f:long)
 %}
 
 %{
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,22)
+#include <linux/signalfd.h>
+#endif
+%}
+function _signalfd4_flags_str:string(f:long)
+%{ /* pure */
+  long flags = THIS->f;
+  char *str = THIS->__retvalue;
+  int len;
+
+#if defined(SFD_CLOEXEC) && defined(SFD_NONBLOCK)
+  if (flags & SFD_NONBLOCK)
+    strlcat(str, "SFD_NONBLOCK|", MAXSTRINGLEN);
+  if (flags & SFD_CLOEXEC)
+    strlcat(str, "SFD_CLOEXEC|", MAXSTRINGLEN);
+#endif
+
+  len = strlen(str);
+  if (len)
+    str[strlen(str)-1] = 0;
+%}
+
+%{
 #include <linux/inotify.h>
 %}
 function _inotify_init1_flag_str:string(f:long)
diff --git a/tapset/syscalls2.stp b/tapset/syscalls2.stp
index da6b637e..31a29560 100644
--- a/tapset/syscalls2.stp
+++ b/tapset/syscalls2.stp
@@ -2524,16 +2524,28 @@ probe syscall.signal.return = kernel.function("SyS_signal").return !,
 # long compat_sys_signalfd(int ufd, const compat_sigset_t __user *sigmask,
 # 		 compat_size_t sigsetsize)
 #
-probe syscall.signalfd = kernel.function("SyS_signalfd").call !,
+probe syscall.signalfd = kernel.function("SyS_signalfd4").call !,
+                         kernel.function("sys_signalfd4").call !,
+                         kernel.function("SyS_signalfd").call !,
                          kernel.function("sys_signalfd").call ?
 {
-	name = "signalfd"
-	argstr = sprintf("%d, %p, %d", $ufd, $user_mask, $sizemask)
+	flags = @defined($flags) ? $flags : 0;
+	if (flags == 0) {
+		name = "signalfd"
+		argstr = sprintf("%d, %p, %d", $ufd, $user_mask, $sizemask)
+	} else {
+		name = "signalfd4"
+		argstr = sprintf("%d, %p, %d, %s", $ufd, $user_mask,
+		       	 	 $sizemask, _signalfd4_flags_str($flags))
+	}
 }
-probe syscall.signalfd.return = kernel.function("SyS_signalfd").return !,
+probe syscall.signalfd.return = kernel.function("SyS_signalfd4").return !,
+                                kernel.function("sys_signalfd4").return !,
+                                kernel.function("SyS_signalfd").return !,
                                 kernel.function("sys_signalfd").return ?
 {
-	name = "signalfd"
+	flags = @defined($flags) ? $flags : 0;
+	name = (flags == 0) ? "signalfd" : "signalfd4"
 	retstr = returnstr(1)
 }
 probe syscall.compat_signalfd = kernel.function("compat_sys_signalfd").call ?
diff --git a/testsuite/systemtap.syscall/signalfd.c b/testsuite/systemtap.syscall/signalfd.c
new file mode 100644
index 00000000..e4621bf9
--- /dev/null
+++ b/testsuite/systemtap.syscall/signalfd.c
@@ -0,0 +1,35 @@
+/* COVERAGE: signalfd */
+#include <sys/signalfd.h>
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <signal.h>
+#include <string.h>
+
+int main()
+{
+  sigset_t mask;
+  int sfd;
+
+  sigemptyset(&mask);
+  sigaddset(&mask, SIGINT);
+  sigaddset(&mask, SIGQUIT);
+  sfd = signalfd(-1, &mask, 0);
+  //staptest// signalfd (-1, XXXX, NNNN) = NNNN
+
+  sigaddset(&mask, SIGUSR1);
+  sigaddset(&mask, SIGUSR2);
+  sfd = signalfd(sfd, &mask, 0);
+  //staptest// signalfd (NNNN, XXXX, NNNN) = NNNN
+
+#if defined(SFD_NONBLOCK) && defined(SFD_CLOEXEC)
+  sfd = signalfd(-1, &mask, SFD_NONBLOCK);
+  //staptest// signalfd4 (-1, XXXX, NNNN, SFD_NONBLOCK) = NNNN
+  sfd = signalfd(-1, &mask, SFD_CLOEXEC);
+  //staptest// signalfd4 (-1, XXXX, NNNN, SFD_CLOEXEC) = NNNN
+  sfd = signalfd(-1, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
+  //staptest// signalfd4 (-1, XXXX, NNNN, SFD_NONBLOCK|SFD_CLOEXEC) = NNNN
+#endif
+
+  return 0;
+}