[COMMITTED] benchtests: Update README to include instructions for bench-build target

[COMMITTED] benchtests: Update README to include instructions for bench-build target

[Siddhesh Poyarekar]

---
 ChangeLog         |  3 +++
 benchtests/README | 17 +++++++++++++++++
 2 files changed, 20 insertions(+)

diff --git a/ChangeLog b/ChangeLog
index 9f9270b..74f57db 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,8 @@
 2016-04-20  Siddhesh Poyarekar  <sid@reserved-bit.com>
 
+	benchtests/README: Update README to include instructions on
+	using bench-build.
+
 	Makefile.in (bench-build): New target.
 	Rules (PHONY): Add bench-build target.
 	benchtests/Makefile (bench): Depend on bench-build.
diff --git a/benchtests/README b/benchtests/README
index 999d268..847df87 100644
--- a/benchtests/README
+++ b/benchtests/README
@@ -34,6 +34,23 @@ the benchmark to use clock_gettime by invoking make as follows:
 
 Again, one must run `make bench-clean' before changing the measurement method.
 
+Running benchmarks on another target:
+====================================
+
+If the target where you want to run benchmarks is not capable of building the
+code or you're cross-building, you could build and execute the benchmark in
+separate steps.  On the build system run:
+
+  $ make bench-build
+
+and then copy the source and build directories to the target and run the
+benchmarks from the build directory as usual:
+
+  $ make bench
+
+make sure the copy preserves timestamps by using either rsync or scp -p
+otherwise the above command may try to build the benchmark again.
+
 Adding a function to benchtests:
 ===============================
 
-- 
2.5.5