Bump up the runtime for "short" benchmarks

Some benchmarks with a very short runtime show significantly
different results across runs on Aarch64 - up to tens of percents.
Increasing the runtime to 100ms+ makes the deviation under 5%.

Tested on Aarch64 and x86-64.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>

	* benchtests/bench-memccpy.c: Replace INNER_LOOP_ITERS
	with INNER_LOOP_ITERS_LARGE.
	* benchtests/bench-memchr.c: Likewise.
	* benchtests/bench-rawmemchr.c: Likewise.
	* benchtests/bench-strcat.c: Likewise.
	* benchtests/bench-strchr.c: Likewise.
	* benchtests/bench-string.h: Likewise.
	* benchtests/bench-strlen.c: Likewise.
	* benchtests/bench-strncpy.c: Likewise.
	* benchtests/bench-strnlen.c: Likewise.

10 files changed, 22 insertions, 8 deletions

diff --git a/ChangeLog b/ChangeLog
index 65129ff43a..718829d172 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,16 @@
+2019-06-28  Anton Youdkevitch  <anton.youdkevitch@bell-sw.com>
+
+	* benchtests/bench-memccpy.c: Replace INNER_LOOP_ITERS
+	with INNER_LOOP_ITERS_LARGE.
+	* benchtests/bench-memchr.c: Likewise.
+	* benchtests/bench-rawmemchr.c: Likewise.
+	* benchtests/bench-strcat.c: Likewise.
+	* benchtests/bench-strchr.c: Likewise.
+	* benchtests/bench-string.h: Likewise.
+	* benchtests/bench-strlen.c: Likewise.
+	* benchtests/bench-strncpy.c: Likewise.
+	* benchtests/bench-strnlen.c: Likewise.
+
 2019-06-28  Florian Weimer  <fweimer@redhat.com>
 
 	* sysdeps/unix/sysv/linux/tst-getdents64.c (large_buffer_checks):
diff --git a/benchtests/bench-memccpy.c b/benchtests/bench-memccpy.c
index d3a2df5e72..46f96d58c5 100644
--- a/benchtests/bench-memccpy.c
+++ b/benchtests/bench-memccpy.c
@@ -41,7 +41,7 @@ static void
 do_one_test (impl_t *impl, void *dst, const void *src, int c, size_t len,
 	     size_t n)
 {
-  size_t i, iters = INNER_LOOP_ITERS;
+  size_t i, iters = INNER_LOOP_ITERS_LARGE;
   timing_t start, stop, cur;
 
   TIMING_NOW (start);
diff --git a/benchtests/bench-memchr.c b/benchtests/bench-memchr.c
index 9bd07eba75..8a9909a984 100644
--- a/benchtests/bench-memchr.c
+++ b/benchtests/bench-memchr.c
@@ -56,7 +56,7 @@ SIMPLE_MEMCHR (const CHAR *s, int c, size_t n)
 static void
 do_one_test (impl_t *impl, const CHAR *s, int c, size_t n)
 {
-  size_t i, iters = INNER_LOOP_ITERS;
+  size_t i, iters = INNER_LOOP_ITERS_LARGE;
   timing_t start, stop, cur;
 
   TIMING_NOW (start);
diff --git a/benchtests/bench-rawmemchr.c b/benchtests/bench-rawmemchr.c
index 44f3114fd2..5cdfdf7227 100644
--- a/benchtests/bench-rawmemchr.c
+++ b/benchtests/bench-rawmemchr.c
@@ -39,7 +39,7 @@ IMPL (generic_rawmemchr, 0)
 static void
 do_one_test (impl_t *impl, const char *s, int c, char *exp_res)
 {
-  size_t i, iters = INNER_LOOP_ITERS;
+  size_t i, iters = INNER_LOOP_ITERS_LARGE;
   timing_t start, stop, cur;
   char *res = CALL (impl, s, c);
   if (res != exp_res)
diff --git a/benchtests/bench-strcat.c b/benchtests/bench-strcat.c
index 39d9fefb09..08841d037f 100644
--- a/benchtests/bench-strcat.c
+++ b/benchtests/bench-strcat.c
@@ -51,7 +51,7 @@ IMPL (generic_strcat, 0)
 static void
 do_one_test (impl_t *impl, CHAR *dst, const CHAR *src)
 {
-  size_t k = STRLEN (dst), i, iters = INNER_LOOP_ITERS;
+  size_t k = STRLEN (dst), i, iters = INNER_LOOP_ITERS_LARGE;
   timing_t start, stop, cur;
 
   if (CALL (impl, dst, src) != dst)
diff --git a/benchtests/bench-strchr.c b/benchtests/bench-strchr.c
index b8dba17cae..10d06feb23 100644
--- a/benchtests/bench-strchr.c
+++ b/benchtests/bench-strchr.c
@@ -76,7 +76,7 @@ IMPL (STRCHR, 1)
 static void
 do_one_test (impl_t *impl, const CHAR *s, int c, const CHAR *exp_res)
 {
-  size_t i, iters = INNER_LOOP_ITERS;
+  size_t i, iters = INNER_LOOP_ITERS_LARGE;
   timing_t start, stop, cur;
 
   TIMING_NOW (start);
diff --git a/benchtests/bench-string.h b/benchtests/bench-string.h
index e7fb015bc6..7d357914fd 100644
--- a/benchtests/bench-string.h
+++ b/benchtests/bench-string.h
@@ -125,6 +125,7 @@ extern impl_t __start_impls[], __stop_impls[];
 # define OPT_SEED 10002
 
 # define INNER_LOOP_ITERS 8192
+# define INNER_LOOP_ITERS_LARGE 131072
 # define INNER_LOOP_ITERS_MEDIUM 1024
 # define INNER_LOOP_ITERS_SMALL 32
 
diff --git a/benchtests/bench-strlen.c b/benchtests/bench-strlen.c
index 47363af0f7..1997ad75b4 100644
--- a/benchtests/bench-strlen.c
+++ b/benchtests/bench-strlen.c
@@ -48,7 +48,7 @@ IMPL (STRLEN, 1)
 static void
 do_one_test (json_ctx_t *json_ctx, impl_t *impl, const CHAR *s, size_t exp_len)
 {
-  size_t len = CALL (impl, s), i, iters = INNER_LOOP_ITERS;
+  size_t len = CALL (impl, s), i, iters = INNER_LOOP_ITERS_LARGE;
   timing_t start, stop, cur;
 
   if (len != exp_len)
diff --git a/benchtests/bench-strncpy.c b/benchtests/bench-strncpy.c
index 93bd6d54bf..c6a6799a2f 100644
--- a/benchtests/bench-strncpy.c
+++ b/benchtests/bench-strncpy.c
@@ -54,7 +54,7 @@ typedef CHAR *(*proto_t) (CHAR *, const CHAR *, size_t);
 static void
 do_one_test (impl_t *impl, CHAR *dst, const CHAR *src, size_t len, size_t n)
 {
-  size_t i, iters = INNER_LOOP_ITERS;
+  size_t i, iters = INNER_LOOP_ITERS_LARGE;
   timing_t start, stop, cur;
 
   if (CALL (impl, dst, src, n) != STRNCPY_RESULT (dst, len, n))
diff --git a/benchtests/bench-strnlen.c b/benchtests/bench-strnlen.c
index e9e51b27fc..72ec303977 100644
--- a/benchtests/bench-strnlen.c
+++ b/benchtests/bench-strnlen.c
@@ -51,7 +51,7 @@ IMPL (generic_strnlen, 0)
 static void
 do_one_test (impl_t *impl, const CHAR *s, size_t maxlen, size_t exp_len)
 {
-  size_t len = CALL (impl, s, maxlen), i, iters = INNER_LOOP_ITERS;
+  size_t len = CALL (impl, s, maxlen), i, iters = INNER_LOOP_ITERS_LARGE;
   timing_t start, stop, cur;
 
   if (len != exp_len)