mm: add infrastructure for get_user_pages_fast() benchmarking
Performance of get_user_pages_fast() is critical for some workloads, but
it's tricky to test it directly.
This patch provides /sys/kernel/debug/gup_benchmark that helps with
testing performance of it.
See tools/testing/selftests/vm/gup_benchmark.c for userspace
counterpart.
Link: http://lkml.kernel.org/r/20170908215603.9189-2-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thorsten Leemhuis <regressions@leemhuis.info>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/Kconfig b/mm/Kconfig
index 9c4bddd..03ff770 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -756,3 +756,12 @@
This feature collects and exposes statistics via debugfs. The
information includes global and per chunk statistics, which can
be used to help understand percpu memory usage.
+
+config GUP_BENCHMARK
+ bool "Enable infrastructure for get_user_pages_fast() benchmarking"
+ default n
+ help
+ Provides /sys/kernel/debug/gup_benchmark that helps with testing
+ performance of get_user_pages_fast().
+
+ See tools/testing/selftests/vm/gup_benchmark.c