trace: Format strings must begin/end with double quotes
Document the restriction that format strings must begin and end with
double quotes. This is for easy parsing since we don't run cpp over
trace-events.
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
diff --git a/docs/tracing.txt b/docs/tracing.txt
index 5504850..963c504 100644
--- a/docs/tracing.txt
+++ b/docs/tracing.txt
@@ -74,7 +74,10 @@
Format strings should reflect the types defined in the trace event. Take
special care to use PRId64 and PRIu64 for int64_t and uint64_t types,
-respectively. This ensures portability between 32- and 64-bit platforms.
+respectively. This ensures portability between 32- and 64-bit platforms. Note
+that format strings must begin and end with double quotes. When using
+portability macros, ensure they are preceded and followed by double quotes:
+"value %"PRIx64"".
=== Hints for adding new trace events ===
