[PATCH] perf, tools: Add description of JIT interface

[Andi Kleen <andi@firstfloor.org>]

From: Andi Kleen <ak@linux.intel.com>

Add a description of the JIT interface in the perf symbol resolution
code. I reverse engineered the format from the source.

Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
---
 tools/perf/Documentation/jit-interface.txt |   16 ++++++++++++++++
 1 files changed, 16 insertions(+), 0 deletions(-)
 create mode 100644 tools/perf/Documentation/jit-interface.txt

diff --git a/tools/perf/Documentation/jit-interface.txt b/tools/perf/Documentation/jit-interface.txt
new file mode 100644
index 0000000..aa66735
--- /dev/null
+++ b/tools/perf/Documentation/jit-interface.txt
@@ -0,0 +1,16 @@
+perf supports a simple JIT interface to resolve symbols for dynamic code generated
+by a JIT.
+
+The JIT has to write a /tmp/perf-%d.map  (%d = pid of process) file
+
+This is a text file.
+
+Each line has the following format, fields separated with spaces.
+
+START SIZE symbolname
+
+START and SIZE are hex numbers without 0x
+symbolname is the rest of the line, so it could contain special characters.
+
+The ownership of the file has to match the process.
+
-- 
1.7.7.6