1 files changed, 40 insertions, 14 deletions

diff --git a/trace-recorder.c b/trace-recorder.c
index 2a754b9..e57ef9b 100644
--- a/trace-recorder.c
+++ b/trace-recorder.c
@@ -128,11 +128,39 @@ struct tracecmd_recorder *tracecmd_create_recorder(const char *file, int cpu)
         return recorder;
 }
 
+/*
+ * Returns -1 on error.
+ *          or bytes of data read.
+ */
+static long splice_data(struct tracecmd_recorder *recorder)
+{
+        long ret;
+
+        ret = splice(recorder->trace_fd, NULL, recorder->brass[1], NULL,
+                     recorder->page_size, 1 /* SPLICE_F_MOVE */);
+        if (ret < 0) {
+                warning("recorder error in splice input");
+                return -1;
+        }
+
+        ret = splice(recorder->brass[0], NULL, recorder->fd, NULL,
+                     recorder->page_size, 3 /* and NON_BLOCK */);
+        if (ret < 0) {
+                if (errno != EAGAIN) {
+                        warning("recorder error in splice output");
+                        return -1;
+                }
+                ret = 0;
+        }
+
+        return ret;
+}
+
 int tracecmd_start_recording(struct tracecmd_recorder *recorder, unsigned long sleep)
 {
         struct timespec req;
         char *buf[recorder->page_size];
-        int ret;
+        long ret;
 
         recorder->stop = 0;
 
@@ -142,21 +170,19 @@ int tracecmd_start_recording(struct tracecmd_recorder *recorder, unsigned long s
                         req.tv_nsec = (sleep % 1000000) * 1000;
                         nanosleep(&req, NULL);
                 }
-
-                ret = splice(recorder->trace_fd, NULL, recorder->brass[1], NULL,
-                             recorder->page_size, 1 /* SPLICE_F_MOVE */);
-                if (ret < 0) {
-                        warning("recorder error in splice input");
-                        return -1;
-                }
-                ret = splice(recorder->brass[0], NULL, recorder->fd, NULL,
-                             recorder->page_size, 3 /* and NON_BLOCK */);
-                if (ret < 0 && errno != EAGAIN) {
-                        warning("recorder error in splice output");
-                        return -1;
-                }
+                ret = splice_data(recorder);
+                if (ret < 0)
+                        return ret;
         } while (!recorder->stop);
 
+        /* Flush via splice first */
+        do {
+                ret = splice_data(recorder);
+        } while (ret > 0);
+
+        if (ret < 0)
+                return ret;
+
         /* splice only reads full pages */
         do {
                 ret = read(recorder->trace_fd, buf, recorder->page_size);