perf bench mem: Add mmap() workloads

Add two mmap() workloads: one that eagerly populates a region and
another that demand faults it in.

The intent is to probe the memory subsytem performance incurred
by mmap().

  $ perf bench mem mmap -s 4gb -p 4kb -l 10 -f populate
  # Running 'mem/mmap' benchmark:
  # function 'populate' (Eagerly populated map())
  # Copying 4gb bytes ...

       1.811691 GB/sec

  $ perf bench mem mmap -s 4gb -p 2mb -l 10 -f populate
  # Running 'mem/mmap' benchmark:
  # function 'populate' (Eagerly populated mmap())
  # Copying 4gb bytes ...

      12.272017 GB/sec

  $ perf bench mem mmap -s 4gb -p 1gb -l 10 -f populate
  # Running 'mem/mmap' benchmark:
  # function 'populate' (Eagerly populated mmap())
  # Copying 4gb bytes ...

      17.085927 GB/sec

Signed-off-by: Ankur Arora <ankur.a.arora@oracle.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Mateusz Guzik <mjguzik@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Raghavendra K T <raghavendra.kt@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 34 insertions, 0 deletions

diff --git a/tools/perf/Documentation/perf-bench.txt b/tools/perf/Documentation/perf-bench.txt
index 3d1455d880c3..1160224cb718 100644
--- a/tools/perf/Documentation/perf-bench.txt
+++ b/tools/perf/Documentation/perf-bench.txt
@@ -240,6 +240,40 @@ Repeat memset invocation this number of times.
 --cycles::
 Use perf's cpu-cycles event instead of gettimeofday syscall.
 
+*mmap*::
+Suite for evaluating memory subsystem performance for mmap()'d memory.
+
+Options of *mmap*
+^^^^^^^^^^^^^^^^^
+-s::
+--size::
+Specify size of memory to set (default: 1MB).
+Available units are B, KB, MB, GB and TB (case insensitive).
+
+-p::
+--page::
+Specify page-size for mapping memory buffers (default: 4KB).
+Available values are 4KB, 2MB, 1GB (case insensitive).
+
+-r::
+--randomize::
+Specify seed to randomize page access offset (default: 0, or not randomized).
+
+-f::
+--function::
+Specify function to set (default: all).
+Available functions are 'demand' and 'populate', with the first
+demand faulting pages in the region and the second using an eager
+mapping.
+
+-l::
+--nr_loops::
+Repeat mmap() invocation this number of times.
+
+-c::
+--cycles::
+Use perf's cpu-cycles event instead of gettimeofday syscall.
+
 SUITES FOR 'numa'
 ~~~~~~~~~~~~~~~~~
 *mem*::