1 files changed, 129 insertions, 0 deletions
diff --git a/runtime/print_flush.c b/runtime/print_flush.c
new file mode 100644
index 00000000..52017426
--- /dev/null
+++ b/runtime/print_flush.c
@@ -0,0 +1,129 @@
+/* -*- linux-c -*- 
+ * Print Flush Function
+ * Copyright (C) 2007-2008 Red Hat Inc.
+ *
+ * This file is part of systemtap, and is free software.  You can
+ * redistribute it and/or modify it under the terms of the GNU General
+ * Public License (GPL); either version 2, or (at your option) any
+ * later version.
+ */
+
+/** Send the print buffer to the transport now.
+ * Output accumulates in the print buffer until it
+ * is filled, or this is called. This MUST be called before returning
+ * from a probe or accumulated output in the print buffer will be lost.
+ *
+ * @note Preemption must be disabled to use this.
+ */
+
+static DEFINE_SPINLOCK(_stp_print_lock);
+
+void EXPORT_FN(stp_print_flush)(_stp_pbuf *pb)
+{
+	size_t len = pb->len;
+	void *entry = NULL;
+
+	/* check to see if there is anything in the buffer */
+	dbug_trans(1, "len = %zu\n", len);
+	if (likely(len == 0))
+		return;
+
+	pb->len = 0;
+
+	if (unlikely(_stp_transport_get_state() != STP_TRANSPORT_RUNNING))
+		return;
+
+#ifdef STP_BULKMODE
+#ifdef NO_PERCPU_HEADERS
+	{
+		char *bufp = pb->buf;
+
+		while (len > 0) {
+			size_t bytes_reserved;
+
+			bytes_reserved = _stp_data_write_reserve(len, &entry);
+			if (likely(entry && bytes_reserved > 0)) {
+				memcpy(_stp_data_entry_data(entry), bufp,
+				       bytes_reserved);
+				_stp_data_write_commit(entry);
+				bufp += bytes_reserved;
+				len -= bytes_reserved;
+			}
+			else {
+				atomic_inc(&_stp_transport_failures);
+				break;
+			}
+		}
+	}
+
+#else  /* !NO_PERCPU_HEADERS */
+
+	{
+		char *bufp = pb->buf;
+		struct _stp_trace t = {	.sequence = _stp_seq_inc(),
+					.pdu_len = len};
+		size_t bytes_reserved;
+
+		bytes_reserved = _stp_data_write_reserve(sizeof(struct _stp_trace), &entry);
+		if (likely(entry && bytes_reserved > 0)) {
+			/* prevent unaligned access by using memcpy() */
+			memcpy(_stp_data_entry_data(entry), &t, sizeof(t));
+			_stp_data_write_commit(entry);
+		}
+		else {
+			atomic_inc(&_stp_transport_failures);
+			return;
+		}
+
+		while (len > 0) {
+			bytes_reserved = _stp_data_write_reserve(len, &entry);
+			if (likely(entry && bytes_reserved > 0)) {
+				memcpy(_stp_data_entry_data(entry), bufp,
+				       bytes_reserved);
+				_stp_data_write_commit(entry);
+				bufp += bytes_reserved;
+				len -= bytes_reserved;
+			}
+			else {
+				atomic_inc(&_stp_transport_failures);
+				break;
+			}
+		}
+	}
+#endif /* !NO_PERCPU_HEADERS */
+
+#else  /* !STP_BULKMODE */
+
+#if STP_TRANSPORT_VERSION == 1
+
+	if (unlikely(_stp_ctl_write(STP_REALTIME_DATA, pb->buf, len) <= 0))
+		atomic_inc (&_stp_transport_failures);
+
+#else  /* STP_TRANSPORT_VERSION != 1 */
+	{
+		unsigned long flags;
+		char *bufp = pb->buf;
+
+		dbug_trans(1, "calling _stp_data_write...\n");
+		spin_lock_irqsave(&_stp_print_lock, flags);
+		while (len > 0) {
+			size_t bytes_reserved;
+
+			bytes_reserved = _stp_data_write_reserve(len, &entry);
+			if (likely(entry && bytes_reserved > 0)) {
+				memcpy(_stp_data_entry_data(entry), bufp,
+				       bytes_reserved);
+				_stp_data_write_commit(entry);
+				bufp += bytes_reserved;
+				len -= bytes_reserved;
+			}
+			else {
+			    atomic_inc(&_stp_transport_failures);
+			    break;
+			}
+		}
+		spin_unlock_irqrestore(&_stp_print_lock, flags);
+	}
+#endif /* STP_TRANSPORT_VERSION != 1 */
+#endif /* !STP_BULKMODE */
+}