[v8,11/15] xenpm: Print HWP/CPPC parameters

Commit Message

Jason Andryuk Aug. 7, 2023, 6:51 p.m. UTC

Print HWP-specific parameters.  Some are always present, but others
depend on hardware support.

Signed-off-by: Jason Andryuk <[e-mail]>
Reviewed-by: Jan Beulich <[e-mail]>
---
v2:
Style fixes
Declare i outside loop
Replace repearted hardware/configured limits with spaces
Fixup for hw_ removal
Use XEN_HWP_GOVERNOR
Use HWP_ACT_WINDOW_EXPONENT_*
Remove energy_perf hw autonomous - 0 doesn't mean autonomous

v4:
Return activity_window from calculate_hwp_activity_window
Use blanks instead of _ in output
Use MASK_EXTR
Check XEN_HWP_DRIVER name since governor is no longer returned
s/hwp/cppc

v5:
Add Jan's Reviewed-by

v8:
Switch from "if ( !hwp )" to "if ( hwp )" and re-org code.
Use %PRIu32 instead of %u - this lengthens some strings past 80 chars
---
 tools/misc/xenpm.c | 68 +++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 67 insertions(+), 1 deletion(-)

Comments

Anthony PERARD Aug. 8, 2023, 8:56 a.m. UTC | #1

On Mon, Aug 07, 2023 at 02:51:15PM -0400, Jason Andryuk wrote:
> Print HWP-specific parameters.  Some are always present, but others
> depend on hardware support.
> 
> Signed-off-by: Jason Andryuk <[e-mail]>
> Reviewed-by: Jan Beulich <[e-mail]>
> ---
> v8:
> Switch from "if ( !hwp )" to "if ( hwp )" and re-org code.
> Use %PRIu32 instead of %u - this lengthens some strings past 80 chars

Reviewed-by: Anthony PERARD <[e-mail]>

Thanks,

Patch

diff --git a/tools/misc/xenpm.c b/tools/misc/xenpm.c
index 3f5b2afcea..688529b59d 100644
--- a/tools/misc/xenpm.c
+++ b/tools/misc/xenpm.c
@@ -708,6 +708,46 @@  void start_gather_func(int argc, char *argv[])
     pause();
 }
 
+static unsigned int calculate_activity_window(const xc_cppc_para_t *cppc,
+                                              const char **units)
+{
+    unsigned int mantissa = MASK_EXTR(cppc->activity_window,
+                                      XEN_CPPC_ACT_WINDOW_MANTISSA_MASK);
+    unsigned int exponent = MASK_EXTR(cppc->activity_window,
+                                      XEN_CPPC_ACT_WINDOW_EXPONENT_MASK);
+    unsigned int multiplier = 1;
+    unsigned int i;
+
+    /*
+     * SDM only states a 0 register is hardware selected, and doesn't mention
+     * a 0 mantissa with a non-0 exponent.  Only special case a 0 register.
+     */
+    if ( cppc->activity_window == 0 )
+    {
+        *units = "hardware selected";
+
+        return 0;
+    }
+
+    if ( exponent >= 6 )
+    {
+        *units = "s";
+        exponent -= 6;
+    }
+    else if ( exponent >= 3 )
+    {
+        *units = "ms";
+        exponent -= 3;
+    }
+    else
+        *units = "us";
+
+    for ( i = 0; i < exponent; i++ )
+        multiplier *= 10;
+
+    return mantissa * multiplier;
+}
+
 /* print out parameters about cpu frequency */
 static void print_cpufreq_para(int cpuid, struct xc_get_cpufreq_para *p_cpufreq)
 {
@@ -733,7 +773,33 @@  static void print_cpufreq_para(int cpuid, struct xc_get_cpufreq_para *p_cpufreq)
 
     printf("scaling_driver       : %s\n", p_cpufreq->scaling_driver);
 
-    if ( !hwp )
+    if ( hwp )
+    {
+        const xc_cppc_para_t *cppc = &p_cpufreq->u.cppc_para;
+
+        printf("cppc variables       :\n");
+        printf("  hardware limits    : lowest [%"PRIu32"] lowest nonlinear [%"PRIu32"]\n",
+               cppc->lowest, cppc->lowest_nonlinear);
+        printf("                     : nominal [%"PRIu32"] highest [%"PRIu32"]\n",
+               cppc->nominal, cppc->highest);
+        printf("  configured limits  : min [%"PRIu32"] max [%"PRIu32"] energy perf [%"PRIu32"]\n",
+               cppc->minimum, cppc->maximum, cppc->energy_perf);
+
+        if ( cppc->features & XEN_SYSCTL_CPPC_FEAT_ACT_WINDOW )
+        {
+            unsigned int activity_window;
+            const char *units;
+
+            activity_window = calculate_activity_window(cppc, &units);
+            printf("                     : activity_window [%"PRIu32" %s]\n",
+                   activity_window, units);
+        }
+
+        printf("                     : desired [%"PRIu32"%s]\n",
+               cppc->desired,
+               cppc->desired ? "" : " hw autonomous");
+    }
+    else
     {
         printf("scaling_avail_gov    : %s\n",
                p_cpufreq->scaling_available_governors);