[PATCH v2 08/12] lib/crypto: tests: Add Curve25519 benchmark

[Eric Biggers]

Add a benchmark to curve25519_kunit.  This brings it in line with the
other crypto KUnit tests and provides an easy way to measure
performance.

Signed-off-by: Eric Biggers <ebigg...@kernel.org>
---
 lib/crypto/tests/curve25519_kunit.c | 31 +++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/lib/crypto/tests/curve25519_kunit.c 
b/lib/crypto/tests/curve25519_kunit.c
index 0d1c46ca74018..355ad79a210d1 100644
--- a/lib/crypto/tests/curve25519_kunit.c
+++ b/lib/crypto/tests/curve25519_kunit.c
@@ -3,10 +3,11 @@
  * Copyright (C) 2015-2019 Jason A. Donenfeld <ja...@zx2c4.com>. All Rights 
Reserved.
  */
 
 #include <crypto/curve25519.h>
 #include <kunit/test.h>
+#include <linux/timekeeping.h>
 
 struct curve25519_test_vector {
        u8 private[CURVE25519_KEY_SIZE];
        u8 public[CURVE25519_KEY_SIZE];
        u8 result[CURVE25519_KEY_SIZE];
@@ -1314,13 +1315,43 @@ static void test_curve25519_basepoint(struct kunit 
*test)
                KUNIT_EXPECT_MEMEQ_MSG(test, out, out2, CURVE25519_KEY_SIZE,
                                       "in=%*phN", CURVE25519_KEY_SIZE, in);
        }
 }
 
+static void benchmark_curve25519(struct kunit *test)
+{
+       const u8 *private = curve25519_test_vectors[0].private;
+       const u8 *public = curve25519_test_vectors[0].public;
+       const size_t warmup_niter = 5000;
+       const size_t benchmark_niter = 1024;
+       u8 out[CURVE25519_KEY_SIZE];
+       bool ok = true;
+       u64 t;
+
+       if (!IS_ENABLED(CONFIG_CRYPTO_LIB_BENCHMARK))
+               kunit_skip(test, "not enabled");
+
+       /* Warm-up */
+       for (size_t i = 0; i < warmup_niter; i++)
+               ok &= curve25519(out, private, public);
+
+       /* Benchmark */
+       preempt_disable();
+       t = ktime_get_ns();
+       for (size_t i = 0; i < benchmark_niter; i++)
+               ok &= curve25519(out, private, public);
+       t = ktime_get_ns() - t;
+       preempt_enable();
+       KUNIT_EXPECT_TRUE(test, ok);
+       kunit_info(test, "%llu ops/s",
+                  div64_u64((u64)benchmark_niter * NSEC_PER_SEC, t ?: 1));
+}
+
 static struct kunit_case curve25519_test_cases[] = {
        KUNIT_CASE(test_curve25519),
        KUNIT_CASE(test_curve25519_basepoint),
+       KUNIT_CASE(benchmark_curve25519),
        {},
 };
 
 static struct kunit_suite curve25519_test_suite = {
        .name = "curve25519",
-- 
2.50.1