Make hw.setperf percentages proportional to the enhanced speed step

frequencies on intel processors. This way, the default hw.setperf=99
corresponds to the maximum ordinary speed while setting it to 100
enables turbo mode.

Tested in snaps for a week, positive feedback from several.

diff --git a/sys/arch/amd64/amd64/est.c b/sys/arch/amd64/amd64/est.c
index 547ae08..9565de6 100644 (file)
--- a/sys/arch/amd64/amd64/est.c
+++ b/sys/arch/amd64/amd64/est.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: est.c,v 1.39 2016/03/06 22:41:24 naddy Exp $ */
+/*     $OpenBSD: est.c,v 1.40 2021/08/11 18:15:50 tb Exp $ */
 /*
  * Copyright (c) 2003 Michael Eriksson.
  * All rights reserved.
@@ -83,6 +83,7 @@
 struct est_op {
        uint16_t ctrl;
        uint16_t mhz;
+       uint16_t pct;
 };
 
 struct fqlist {
@@ -229,10 +230,16 @@ est_acpi_init(void)
        struct acpicpu_pss *pss;
        struct fqlist *acpilist;
        int nstates, i;
+       int high, low;
 
        if ((nstates = acpicpu_fetch_pss(&pss)) == 0)
                goto nolist;
 
+       high = pss[0].pss_core_freq;
+       low = pss[nstates - 1].pss_core_freq;
+       if (high - low <= 0)
+               goto nolist;
+
        if ((acpilist = malloc(sizeof(struct fqlist), M_DEVBUF, M_NOWAIT))
            == NULL)
                goto nolist;
@@ -246,6 +253,8 @@ est_acpi_init(void)
        for (i = 0; i < nstates; i++) {
                acpilist->table[i].mhz = pss[i].pss_core_freq;
                acpilist->table[i].ctrl = pss[i].pss_ctrl;
+               acpilist->table[i].pct =
+                   (pss[i].pss_core_freq - low) * 100 / (high - low);
        }
 
        acpicpu_set_notify(est_acpi_pss_changed);
@@ -264,12 +273,21 @@ est_acpi_pss_changed(struct acpicpu_pss *pss, int npss)
 {
        struct fqlist *acpilist;
        int needtran = 1, i;
+       int high, low;
        u_int64_t msr;
        u_int16_t cur;
 
        msr = rdmsr(MSR_PERF_STATUS);
        cur = msr & 0xffff;
 
+       high = pss[0].pss_core_freq;
+       low = pss[npss - 1].pss_core_freq;
+       if (high - low <= 0) {
+               printf("est_acpi_pss_changed: new est state has no "
+                   "speed step\n");
+               return;
+       }
+
        if ((acpilist = malloc(sizeof(struct fqlist), M_DEVBUF, M_NOWAIT))
            == NULL) {
                printf("est_acpi_pss_changed: cannot allocate memory for new "
@@ -288,6 +306,8 @@ est_acpi_pss_changed(struct acpicpu_pss *pss, int npss)
        for (i = 0; i < npss; i++) {
                acpilist->table[i].mhz = pss[i].pss_core_freq;
                acpilist->table[i].ctrl = pss[i].pss_ctrl;
+               acpilist->table[i].pct =
+                   (pss[i].pss_core_freq - low) * 100 / (high - low);
                if (pss[i].pss_ctrl == cur)
                        needtran = 0;
        }
@@ -392,18 +412,25 @@ est_init(struct cpu_info *ci)
                        printf("%s: using only highest and lowest power "
                               "states\n", cpu_device);
 
+                       fake_table[0].pct = 51;
+
                        fake_table[1].ctrl = idlo;
                        fake_table[1].mhz = MSR2MHZ(idlo, bus_clock);
+                       fake_table[1].pct = 0;
                        fake_fqlist->n = 2;
                } else {
                        printf("%s: using only highest, current and lowest "
                            "power states\n", cpu_device);
 
+                       fake_table[0].pct = 67;
+
                        fake_table[1].ctrl = cur;
                        fake_table[1].mhz = MSR2MHZ(cur, bus_clock);
+                       fake_table[1].pct = 34;
 
                        fake_table[2].ctrl = idlo;
                        fake_table[2].mhz = MSR2MHZ(idlo, bus_clock);
+                       fake_table[2].pct = 0;
                        fake_fqlist->n = 3;
                }
 
@@ -454,10 +481,10 @@ est_setperf(int level)
        if (est_fqlist == NULL)
                return;
 
-       i = ((level * est_fqlist->n) + 1) / 101;
-       if (i >= est_fqlist->n)
-               i = est_fqlist->n - 1;
-       i = est_fqlist->n - 1 - i;
+       for (i = 0; i < est_fqlist->n; i++) {
+               if (level >= est_fqlist->table[i].pct)
+                       break;
+       }
 
        msr = rdmsr(MSR_PERF_CTL);
        msr &= ~0xffffULL;