[dpdk-stable] [20.11.3] test/power: fix CPU frequency when turbo enabled

[dpdk-stable] [20.11.3] test/power: fix CPU frequency when turbo enabled

[David Hunt]

On arm platform, the value in "/sys/.../cpuinfo_cur_freq" may not
be exactly the same as what was set when using CPPC cpufreq driver.
For other cpufreq driver, no need to round it currently, or else
this check will fail with turbo enabled. For example, with acpi_cpufreq,
cpuinfo_cur_freq can be 2401000 which is equal to freqs[0].It should
not be rounded to 2400000.

This is a version of the patch for 20.11.3 that fixes this issue
withouth the dependency of having the CPPC support applied first
(modified version of 29343b9030e38e8c3519ba01cb66724d45b13dc8)

Fixes: 606a234c6d360 ("test/power: round CPU frequency to check")
Cc: stable@dpdk.org

Signed-off-by: David Hunt <david.hunt@intel.com>
---
 app/test/test_power_cpufreq.c | 25 ++++++++++++++++---------
 1 file changed, 16 insertions(+), 9 deletions(-)

diff --git a/app/test/test_power_cpufreq.c b/app/test/test_power_cpufreq.c
index 1c9d5cb48e..94a38010e2 100644
--- a/app/test/test_power_cpufreq.c
+++ b/app/test/test_power_cpufreq.c
@@ -55,7 +55,9 @@ check_cur_freq(unsigned int lcore_id, uint32_t idx, bool turbo)
 	FILE *f;
 	char fullpath[PATH_MAX];
 	char buf[BUFSIZ];
+	enum power_management_env env;
 	uint32_t cur_freq;
+	uint32_t freq_conv;
 	int ret = -1;
 	int i;
 
@@ -80,15 +82,20 @@ check_cur_freq(unsigned int lcore_id, uint32_t idx, bool turbo)
 			goto fail_all;
 
 		cur_freq = strtoul(buf, NULL, TEST_POWER_CONVERT_TO_DECIMAL);
-
-		/* 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;
+		freq_conv = cur_freq;
+
+		env = rte_power_get_env();
+
+		if (env == PM_ENV_PSTATE_CPUFREQ) {
+			/* 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;
+		}
 
 		if (turbo)
 			ret = (freqs[idx] <= freq_conv ? 0 : -1);
-- 
2.17.1

Re: [dpdk-stable] [20.11.3] test/power: fix CPU frequency when turbo enabled

[Luca Boccassi]

On Fri, 2021-08-13 at 15:18 +0100, David Hunt wrote:
> On arm platform, the value in "/sys/.../cpuinfo_cur_freq" may not
> be exactly the same as what was set when using CPPC cpufreq driver.
> For other cpufreq driver, no need to round it currently, or else
> this check will fail with turbo enabled. For example, with acpi_cpufreq,
> cpuinfo_cur_freq can be 2401000 which is equal to freqs[0].It should
> not be rounded to 2400000.
> 
> This is a version of the patch for 20.11.3 that fixes this issue
> withouth the dependency of having the CPPC support applied first
> (modified version of 29343b9030e38e8c3519ba01cb66724d45b13dc8)
> 
> Fixes: 606a234c6d360 ("test/power: round CPU frequency to check")
> Cc: stable@dpdk.org
> 
> Signed-off-by: David Hunt <david.hunt@intel.com>
> ---
>  app/test/test_power_cpufreq.c | 25 ++++++++++++++++---------
>  1 file changed, 16 insertions(+), 9 deletions(-)

Acked-by: Luca Boccassi <luca.boccassi@microsoft.com>

Applied and pushed, thanks (next time, please don't include 
dev@dpdk.org but only stable, given it's a backport - otherwise it gets
filtered).

-- 
Kind regards,
Luca Boccassi