freebsd-dev/sys/x86/cpufreq/hwpstate_intel.c
Pawel Biernacki 7029da5c36 Mark more nodes as CTLFLAG_MPSAFE or CTLFLAG_NEEDGIANT (17 of many)
r357614 added CTLFLAG_NEEDGIANT to make it easier to find nodes that are
still not MPSAFE (or already are but aren’t properly marked).
Use it in preparation for a general review of all nodes.

This is non-functional change that adds annotations to SYSCTL_NODE and
SYSCTL_PROC nodes using one of the soon-to-be-required flags.

Mark all obvious cases as MPSAFE.  All entries that haven't been marked
as MPSAFE before are by default marked as NEEDGIANT

Approved by:	kib (mentor, blanket)
Commented by:	kib, gallatin, melifaro
Differential Revision:	https://reviews.freebsd.org/D23718
2020-02-26 14:26:36 +00:00

638 lines
16 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2018 Intel Corporation
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted providing that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <sys/sbuf.h>
#include <sys/module.h>
#include <sys/systm.h>
#include <sys/errno.h>
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/bus.h>
#include <sys/cpu.h>
#include <sys/smp.h>
#include <sys/proc.h>
#include <sys/sched.h>
#include <machine/cpu.h>
#include <machine/md_var.h>
#include <machine/cputypes.h>
#include <machine/specialreg.h>
#include <contrib/dev/acpica/include/acpi.h>
#include <dev/acpica/acpivar.h>
#include <x86/cpufreq/hwpstate_intel_internal.h>
#include "acpi_if.h"
#include "cpufreq_if.h"
extern uint64_t tsc_freq;
static int intel_hwpstate_probe(device_t dev);
static int intel_hwpstate_attach(device_t dev);
static int intel_hwpstate_detach(device_t dev);
static int intel_hwpstate_suspend(device_t dev);
static int intel_hwpstate_resume(device_t dev);
static int intel_hwpstate_get(device_t dev, struct cf_setting *cf);
static int intel_hwpstate_type(device_t dev, int *type);
static device_method_t intel_hwpstate_methods[] = {
/* Device interface */
DEVMETHOD(device_identify, intel_hwpstate_identify),
DEVMETHOD(device_probe, intel_hwpstate_probe),
DEVMETHOD(device_attach, intel_hwpstate_attach),
DEVMETHOD(device_detach, intel_hwpstate_detach),
DEVMETHOD(device_suspend, intel_hwpstate_suspend),
DEVMETHOD(device_resume, intel_hwpstate_resume),
/* cpufreq interface */
DEVMETHOD(cpufreq_drv_get, intel_hwpstate_get),
DEVMETHOD(cpufreq_drv_type, intel_hwpstate_type),
DEVMETHOD_END
};
struct hwp_softc {
device_t dev;
bool hwp_notifications;
bool hwp_activity_window;
bool hwp_pref_ctrl;
bool hwp_pkg_ctrl;
bool hwp_pkg_ctrl_en;
bool hwp_perf_bias;
bool hwp_perf_bias_cached;
uint64_t req; /* Cached copy of HWP_REQUEST */
uint64_t hwp_energy_perf_bias; /* Cache PERF_BIAS */
uint8_t high;
uint8_t guaranteed;
uint8_t efficient;
uint8_t low;
};
static devclass_t hwpstate_intel_devclass;
static driver_t hwpstate_intel_driver = {
"hwpstate_intel",
intel_hwpstate_methods,
sizeof(struct hwp_softc),
};
DRIVER_MODULE(hwpstate_intel, cpu, hwpstate_intel_driver,
hwpstate_intel_devclass, NULL, NULL);
MODULE_VERSION(hwpstate_intel, 1);
static bool hwpstate_pkg_ctrl_enable = true;
SYSCTL_BOOL(_machdep, OID_AUTO, hwpstate_pkg_ctrl, CTLFLAG_RDTUN,
&hwpstate_pkg_ctrl_enable, 0,
"Set 1 (default) to enable package-level control, 0 to disable");
static int
intel_hwp_dump_sysctl_handler(SYSCTL_HANDLER_ARGS)
{
device_t dev;
struct pcpu *pc;
struct sbuf *sb;
struct hwp_softc *sc;
uint64_t data, data2;
int ret;
sc = (struct hwp_softc *)arg1;
dev = sc->dev;
pc = cpu_get_pcpu(dev);
if (pc == NULL)
return (ENXIO);
sb = sbuf_new(NULL, NULL, 1024, SBUF_FIXEDLEN | SBUF_INCLUDENUL);
sbuf_putc(sb, '\n');
thread_lock(curthread);
sched_bind(curthread, pc->pc_cpuid);
thread_unlock(curthread);
rdmsr_safe(MSR_IA32_PM_ENABLE, &data);
sbuf_printf(sb, "CPU%d: HWP %sabled\n", pc->pc_cpuid,
((data & 1) ? "En" : "Dis"));
if (data == 0) {
ret = 0;
goto out;
}
rdmsr_safe(MSR_IA32_HWP_CAPABILITIES, &data);
sbuf_printf(sb, "\tHighest Performance: %03ju\n", data & 0xff);
sbuf_printf(sb, "\tGuaranteed Performance: %03ju\n", (data >> 8) & 0xff);
sbuf_printf(sb, "\tEfficient Performance: %03ju\n", (data >> 16) & 0xff);
sbuf_printf(sb, "\tLowest Performance: %03ju\n", (data >> 24) & 0xff);
rdmsr_safe(MSR_IA32_HWP_REQUEST, &data);
data2 = 0;
if (sc->hwp_pkg_ctrl && (data & IA32_HWP_REQUEST_PACKAGE_CONTROL))
rdmsr_safe(MSR_IA32_HWP_REQUEST_PKG, &data2);
sbuf_putc(sb, '\n');
#define pkg_print(x, name, offset) do { \
if (!sc->hwp_pkg_ctrl || (data & x) != 0) \
sbuf_printf(sb, "\t%s: %03u\n", name, \
(unsigned)(data >> offset) & 0xff); \
else \
sbuf_printf(sb, "\t%s: %03u\n", name, \
(unsigned)(data2 >> offset) & 0xff); \
} while (0)
pkg_print(IA32_HWP_REQUEST_EPP_VALID,
"Requested Efficiency Performance Preference", 24);
pkg_print(IA32_HWP_REQUEST_DESIRED_VALID,
"Requested Desired Performance", 16);
pkg_print(IA32_HWP_REQUEST_MAXIMUM_VALID,
"Requested Maximum Performance", 8);
pkg_print(IA32_HWP_REQUEST_MINIMUM_VALID,
"Requested Minimum Performance", 0);
#undef pkg_print
sbuf_putc(sb, '\n');
out:
thread_lock(curthread);
sched_unbind(curthread);
thread_unlock(curthread);
ret = sbuf_finish(sb);
if (ret == 0)
ret = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb));
sbuf_delete(sb);
return (ret);
}
static inline int
percent_to_raw(int x)
{
MPASS(x <= 100 && x >= 0);
return (0xff * x / 100);
}
/*
* Given x * 10 in [0, 1000], round to the integer nearest x.
*
* This allows round-tripping nice human readable numbers through this
* interface. Otherwise, user-provided percentages such as 25, 50, 75 get
* rounded down to 24, 49, and 74, which is a bit ugly.
*/
static inline int
round10(int xtimes10)
{
return ((xtimes10 + 5) / 10);
}
static inline int
raw_to_percent(int x)
{
MPASS(x <= 0xff && x >= 0);
return (round10(x * 1000 / 0xff));
}
/* Range of MSR_IA32_ENERGY_PERF_BIAS is more limited: 0-0xf. */
static inline int
percent_to_raw_perf_bias(int x)
{
/*
* Round up so that raw values present as nice round human numbers and
* also round-trip to the same raw value.
*/
MPASS(x <= 100 && x >= 0);
return (((0xf * x) + 50) / 100);
}
static inline int
raw_to_percent_perf_bias(int x)
{
/* Rounding to nice human numbers despite a step interval of 6.67%. */
MPASS(x <= 0xf && x >= 0);
return (((x * 20) / 0xf) * 5);
}
static int
sysctl_epp_select(SYSCTL_HANDLER_ARGS)
{
struct hwp_softc *sc;
device_t dev;
struct pcpu *pc;
uint64_t epb;
uint32_t val;
int ret;
dev = oidp->oid_arg1;
sc = device_get_softc(dev);
if (!sc->hwp_pref_ctrl && !sc->hwp_perf_bias)
return (ENODEV);
pc = cpu_get_pcpu(dev);
if (pc == NULL)
return (ENXIO);
thread_lock(curthread);
sched_bind(curthread, pc->pc_cpuid);
thread_unlock(curthread);
if (sc->hwp_pref_ctrl) {
val = (sc->req & IA32_HWP_REQUEST_ENERGY_PERFORMANCE_PREFERENCE) >> 24;
val = raw_to_percent(val);
} else {
/*
* If cpuid indicates EPP is not supported, the HWP controller
* uses MSR_IA32_ENERGY_PERF_BIAS instead (Intel SDM §14.4.4).
* This register is per-core (but not HT).
*/
if (!sc->hwp_perf_bias_cached) {
ret = rdmsr_safe(MSR_IA32_ENERGY_PERF_BIAS, &epb);
if (ret)
goto out;
sc->hwp_energy_perf_bias = epb;
sc->hwp_perf_bias_cached = true;
}
val = sc->hwp_energy_perf_bias &
IA32_ENERGY_PERF_BIAS_POLICY_HINT_MASK;
val = raw_to_percent_perf_bias(val);
}
MPASS(val >= 0 && val <= 100);
ret = sysctl_handle_int(oidp, &val, 0, req);
if (ret || req->newptr == NULL)
goto out;
if (val > 100) {
ret = EINVAL;
goto out;
}
if (sc->hwp_pref_ctrl) {
val = percent_to_raw(val);
sc->req =
((sc->req & ~IA32_HWP_REQUEST_ENERGY_PERFORMANCE_PREFERENCE)
| (val << 24u));
if (sc->hwp_pkg_ctrl_en)
ret = wrmsr_safe(MSR_IA32_HWP_REQUEST_PKG, sc->req);
else
ret = wrmsr_safe(MSR_IA32_HWP_REQUEST, sc->req);
} else {
val = percent_to_raw_perf_bias(val);
MPASS((val & ~IA32_ENERGY_PERF_BIAS_POLICY_HINT_MASK) == 0);
sc->hwp_energy_perf_bias =
((sc->hwp_energy_perf_bias &
~IA32_ENERGY_PERF_BIAS_POLICY_HINT_MASK) | val);
ret = wrmsr_safe(MSR_IA32_ENERGY_PERF_BIAS,
sc->hwp_energy_perf_bias);
}
out:
thread_lock(curthread);
sched_unbind(curthread);
thread_unlock(curthread);
return (ret);
}
void
intel_hwpstate_identify(driver_t *driver, device_t parent)
{
if (device_find_child(parent, "hwpstate_intel", -1) != NULL)
return;
if (cpu_vendor_id != CPU_VENDOR_INTEL)
return;
if (resource_disabled("hwpstate_intel", 0))
return;
/*
* Intel SDM 14.4.1 (HWP Programming Interfaces):
* Availability of HWP baseline resource and capability,
* CPUID.06H:EAX[bit 7]: If this bit is set, HWP provides several new
* architectural MSRs: IA32_PM_ENABLE, IA32_HWP_CAPABILITIES,
* IA32_HWP_REQUEST, IA32_HWP_STATUS.
*/
if ((cpu_power_eax & CPUTPM1_HWP) == 0)
return;
if (BUS_ADD_CHILD(parent, 10, "hwpstate_intel", -1) == NULL)
return;
if (bootverbose)
device_printf(parent, "hwpstate registered\n");
}
static int
intel_hwpstate_probe(device_t dev)
{
device_set_desc(dev, "Intel Speed Shift");
return (BUS_PROBE_NOWILDCARD);
}
static int
set_autonomous_hwp(struct hwp_softc *sc)
{
struct pcpu *pc;
device_t dev;
uint64_t caps;
int ret;
dev = sc->dev;
pc = cpu_get_pcpu(dev);
if (pc == NULL)
return (ENXIO);
thread_lock(curthread);
sched_bind(curthread, pc->pc_cpuid);
thread_unlock(curthread);
/* XXX: Many MSRs aren't readable until feature is enabled */
ret = wrmsr_safe(MSR_IA32_PM_ENABLE, 1);
if (ret) {
/*
* This is actually a package-level MSR, and only the first
* write is not ignored. So it is harmless to enable it across
* all devices, and this allows us not to care especially in
* which order cores (and packages) are probed. This error
* condition should not happen given we gate on the HWP CPUID
* feature flag, if the Intel SDM is correct.
*/
device_printf(dev, "Failed to enable HWP for cpu%d (%d)\n",
pc->pc_cpuid, ret);
goto out;
}
ret = rdmsr_safe(MSR_IA32_HWP_REQUEST, &sc->req);
if (ret) {
device_printf(dev,
"Failed to read HWP request MSR for cpu%d (%d)\n",
pc->pc_cpuid, ret);
goto out;
}
ret = rdmsr_safe(MSR_IA32_HWP_CAPABILITIES, &caps);
if (ret) {
device_printf(dev,
"Failed to read HWP capabilities MSR for cpu%d (%d)\n",
pc->pc_cpuid, ret);
goto out;
}
/*
* High and low are static; "guaranteed" is dynamic; and efficient is
* also dynamic.
*/
sc->high = IA32_HWP_CAPABILITIES_HIGHEST_PERFORMANCE(caps);
sc->guaranteed = IA32_HWP_CAPABILITIES_GUARANTEED_PERFORMANCE(caps);
sc->efficient = IA32_HWP_CAPABILITIES_EFFICIENT_PERFORMANCE(caps);
sc->low = IA32_HWP_CAPABILITIES_LOWEST_PERFORMANCE(caps);
/* hardware autonomous selection determines the performance target */
sc->req &= ~IA32_HWP_DESIRED_PERFORMANCE;
/* enable HW dynamic selection of window size */
sc->req &= ~IA32_HWP_ACTIVITY_WINDOW;
/* IA32_HWP_REQUEST.Minimum_Performance = IA32_HWP_CAPABILITIES.Lowest_Performance */
sc->req &= ~IA32_HWP_MINIMUM_PERFORMANCE;
sc->req |= sc->low;
/* IA32_HWP_REQUEST.Maximum_Performance = IA32_HWP_CAPABILITIES.Highest_Performance. */
sc->req &= ~IA32_HWP_REQUEST_MAXIMUM_PERFORMANCE;
sc->req |= sc->high << 8;
/* If supported, request package-level control for this CPU. */
if (sc->hwp_pkg_ctrl_en)
ret = wrmsr_safe(MSR_IA32_HWP_REQUEST, sc->req |
IA32_HWP_REQUEST_PACKAGE_CONTROL);
else
ret = wrmsr_safe(MSR_IA32_HWP_REQUEST, sc->req);
if (ret) {
device_printf(dev,
"Failed to setup%s autonomous HWP for cpu%d\n",
sc->hwp_pkg_ctrl_en ? " PKG" : "", pc->pc_cpuid);
goto out;
}
/* If supported, write the PKG-wide control MSR. */
if (sc->hwp_pkg_ctrl_en) {
/*
* "The structure of the IA32_HWP_REQUEST_PKG MSR
* (package-level) is identical to the IA32_HWP_REQUEST MSR
* with the exception of the Package Control field, which does
* not exist." (Intel SDM §14.4.4)
*/
ret = wrmsr_safe(MSR_IA32_HWP_REQUEST_PKG, sc->req);
device_printf(dev,
"Failed to set autonomous HWP for package\n");
}
out:
thread_lock(curthread);
sched_unbind(curthread);
thread_unlock(curthread);
return (ret);
}
static int
intel_hwpstate_attach(device_t dev)
{
struct hwp_softc *sc;
int ret;
sc = device_get_softc(dev);
sc->dev = dev;
/* eax */
if (cpu_power_eax & CPUTPM1_HWP_NOTIFICATION)
sc->hwp_notifications = true;
if (cpu_power_eax & CPUTPM1_HWP_ACTIVITY_WINDOW)
sc->hwp_activity_window = true;
if (cpu_power_eax & CPUTPM1_HWP_PERF_PREF)
sc->hwp_pref_ctrl = true;
if (cpu_power_eax & CPUTPM1_HWP_PKG)
sc->hwp_pkg_ctrl = true;
/* Allow administrators to disable pkg-level control. */
sc->hwp_pkg_ctrl_en = (sc->hwp_pkg_ctrl && hwpstate_pkg_ctrl_enable);
/* ecx */
if (cpu_power_ecx & CPUID_PERF_BIAS)
sc->hwp_perf_bias = true;
ret = set_autonomous_hwp(sc);
if (ret)
return (ret);
SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev),
SYSCTL_STATIC_CHILDREN(_debug), OID_AUTO, device_get_nameunit(dev),
CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_SKIP | CTLFLAG_NEEDGIANT,
sc, 0, intel_hwp_dump_sysctl_handler, "A", "");
SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev),
SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), OID_AUTO,
"epp", CTLTYPE_INT | CTLFLAG_RWTUN | CTLFLAG_NEEDGIANT, dev, 0,
sysctl_epp_select, "I",
"Efficiency/Performance Preference "
"(range from 0, most performant, through 100, most efficient)");
return (cpufreq_register(dev));
}
static int
intel_hwpstate_detach(device_t dev)
{
return (cpufreq_unregister(dev));
}
static int
intel_hwpstate_get(device_t dev, struct cf_setting *set)
{
struct pcpu *pc;
uint64_t rate;
int ret;
if (set == NULL)
return (EINVAL);
pc = cpu_get_pcpu(dev);
if (pc == NULL)
return (ENXIO);
memset(set, CPUFREQ_VAL_UNKNOWN, sizeof(*set));
set->dev = dev;
ret = cpu_est_clockrate(pc->pc_cpuid, &rate);
if (ret == 0)
set->freq = rate / 1000000;
set->volts = CPUFREQ_VAL_UNKNOWN;
set->power = CPUFREQ_VAL_UNKNOWN;
set->lat = CPUFREQ_VAL_UNKNOWN;
return (0);
}
static int
intel_hwpstate_type(device_t dev, int *type)
{
if (type == NULL)
return (EINVAL);
*type = CPUFREQ_TYPE_ABSOLUTE | CPUFREQ_FLAG_INFO_ONLY | CPUFREQ_FLAG_UNCACHED;
return (0);
}
static int
intel_hwpstate_suspend(device_t dev)
{
return (0);
}
/*
* Redo a subset of set_autonomous_hwp on resume; untested. Without this,
* testers observed that on resume MSR_IA32_HWP_REQUEST was bogus.
*/
static int
intel_hwpstate_resume(device_t dev)
{
struct hwp_softc *sc;
struct pcpu *pc;
int ret;
sc = device_get_softc(dev);
pc = cpu_get_pcpu(dev);
if (pc == NULL)
return (ENXIO);
thread_lock(curthread);
sched_bind(curthread, pc->pc_cpuid);
thread_unlock(curthread);
ret = wrmsr_safe(MSR_IA32_PM_ENABLE, 1);
if (ret) {
device_printf(dev,
"Failed to enable HWP for cpu%d after suspend (%d)\n",
pc->pc_cpuid, ret);
goto out;
}
if (sc->hwp_pkg_ctrl_en)
ret = wrmsr_safe(MSR_IA32_HWP_REQUEST, sc->req |
IA32_HWP_REQUEST_PACKAGE_CONTROL);
else
ret = wrmsr_safe(MSR_IA32_HWP_REQUEST, sc->req);
if (ret) {
device_printf(dev,
"Failed to set%s autonomous HWP for cpu%d after suspend\n",
sc->hwp_pkg_ctrl_en ? " PKG" : "", pc->pc_cpuid);
goto out;
}
if (sc->hwp_pkg_ctrl_en) {
ret = wrmsr_safe(MSR_IA32_HWP_REQUEST_PKG, sc->req);
if (ret) {
device_printf(dev,
"Failed to set autonomous HWP for package after "
"suspend\n");
goto out;
}
}
if (!sc->hwp_pref_ctrl && sc->hwp_perf_bias_cached) {
ret = wrmsr_safe(MSR_IA32_ENERGY_PERF_BIAS,
sc->hwp_energy_perf_bias);
if (ret) {
device_printf(dev,
"Failed to set energy perf bias for cpu%d after "
"suspend\n", pc->pc_cpuid);
}
}
out:
thread_lock(curthread);
sched_unbind(curthread);
thread_unlock(curthread);
return (ret);
}