[dpdk-dev] [PATCH v3 1/3] test/power: round cpuinfo cur freq value in cpufreq autotest

[Richael Zhuang <richael.zhuang@arm.com>]

The value in "/sys/.../cpuinfo_cur_freq" may not be exactly the
same as what was set. For example, if "2400000" is written to
"/sys/.../cpufreq/scaling_setspeed" to set the frequency, then the
value in "/sys/.../cpuinfo_cur_freq" may be "2401222". So need to
round the value.

Fixes: ed7c51a6a680 ("app/test: vm power management")
Cc: alan.carew@intel.com
Cc: stable@dpdk.org

Signed-off-by: Richael Zhuang <richael.zhuang@arm.com>
---
 app/test/test_power_cpufreq.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/app/test/test_power_cpufreq.c b/app/test/test_power_cpufreq.c
index 731c6b4dc..1f4d8bb05 100644
--- a/app/test/test_power_cpufreq.c
+++ b/app/test/test_power_cpufreq.c
@@ -34,6 +34,10 @@ test_power_caps(void)
 #define TEST_POWER_LCORE_INVALID ((unsigned)RTE_MAX_LCORE)
 #define TEST_POWER_FREQS_NUM_MAX ((unsigned)RTE_MAX_LCORE_FREQS)
 
+/* macros used for rounding frequency to nearest 100000 */
+#define TEST_FREQ_ROUNDING_DELTA 50000
+#define TEST_ROUND_FREQ_TO_N_100000 100000
+
 #define TEST_POWER_SYSFILE_CUR_FREQ \
 	"/sys/devices/system/cpu/cpu%u/cpufreq/cpuinfo_cur_freq"
 
@@ -62,7 +66,17 @@ check_cur_freq(unsigned lcore_id, uint32_t idx)
 		goto fail_get_cur_freq;
 	}
 	cur_freq = strtoul(buf, NULL, TEST_POWER_CONVERT_TO_DECIMAL);
-	ret = (freqs[idx] == cur_freq ? 0 : -1);
+
+	/* convert the frequency to nearest 100000 value
+	 * Ex: if cur_freq=1396789 then freq_conv=1400000
+	 * Ex: if cur_freq=800030 then freq_conv=800000
+	 */
+	unsigned int freq_conv = 0;
+	freq_conv = (cur_freq + TEST_FREQ_ROUNDING_DELTA)
+				/ TEST_ROUND_FREQ_TO_N_100000;
+	freq_conv = freq_conv * TEST_ROUND_FREQ_TO_N_100000;
+
+	ret = (freqs[idx] == freq_conv ? 0 : -1);
 
 fail_get_cur_freq:
 	fclose(f);
-- 
2.20.1