[CRIU] [PATCH] parasite: Add a comment about interrupt/cont tail calls

[Cyrill Gorcunov]

This patch adds comment why we need interrupt/cont tail
calls in parasite callers code.

Signed-off-by: Cyrill Gorcunov <gorcunov at openvz.org>
---
 parasite-syscall.c |    9 ++++++++-
 1 files changed, 8 insertions(+), 1 deletions(-)

diff --git a/parasite-syscall.c b/parasite-syscall.c
index 5df8ce5..36f5355 100644
--- a/parasite-syscall.c
+++ b/parasite-syscall.c
@@ -185,7 +185,14 @@ retry_signal:
 	}
 
 	/*
-	 * Our code is done.
+	 * Our code is done. But we reach this point when SIGTRAP
+	 * received from the parasite's int3. Drive the tracee back
+	 * to jobctl trap.
+	 *
+	 * This is a bit redundant in our particular case (ie in case
+	 * how we do use ptrace here, since we don't use PTRACE_LISTEN
+	 * at all), but better to be solid in overall design. At least
+	 * for now.
 	 */
 	if (ptrace(PTRACE_INTERRUPT, pid, NULL, NULL)) {
 		pr_err("Can't interrupt (pid: %d)\n", pid);
-- 
1.7.7.6