Pull x86 cpufeature updates from Thomas Gleixner:
- a workaround for the MONITOR instruction erratum of Goldmont CPUs
- small fixes and cleanups here and there
* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/cpu: Add workaround for MONITOR instruction erratum on Goldmont based CPUs
x86/cpu: Rename "WESTMERE2" family to "NEHALEM_G"
x86/amd_nb: Clean up init path
x86/cpufeature: Add helper macro for mask check macros
x86/cpufeature: Make sure DISABLED/REQUIRED macros are updated
x86/cpufeature: Update cpufeaure macros
Commit 5dcef69486 ("intel_idle: add BXT support") added an 8-element
lookup array with just a 2-bit value used for lookups. As per the SDM
that bit field is really 3 bits wide. While this is supposedly benign
here, future re-use of the code for other CPUs might expose the issue.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Since irtl_ns_units[] has itself zero entries, make sure the caller
recognized those cases along with the MSR read returning zero, as zero
is not a valid value for exit_latency and target_residency.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Len Brown noticed something was amiss in our INTEL_FAM6_*
definitions. It seems like model 0x1F was a Nehalem part,
marketed as "Intel Core i7 and i5 Processors" (according to the
SDM). But, although it was a Nehalem 0x1F had some uncore events
which were shared with Westmere.
Len also mentioned he thought it was called "Havendale", which
Wikipedia says was graphics-oriented and canceled:
https://en.wikipedia.org/wiki/Nehalem_(microarchitecture)
So either way, it's probably not imporant what we call it, but
call it Nehalem to be accurate, and add a "G" since it seems
graphics-related. If it were canceled that would be a good reason
why it's so sparsely and inconsistently referred to in the code.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20160629192737.949C41A8@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Denverton is an Intel Atom based micro server which shares the same
Goldmont architecture as Broxton. The available C-states on
Denverton is a subset of Broxton with only C1, C1e, and C6.
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The Kconfig for this driver is currently declared with:
config INTEL_IDLE
bool "Cpuidle Driver for Intel Processors"
...meaning that it currently is not being built as a module by anyone.
This was done in commit 6ce9cd8669
("intel_idle: disable module support") since "...the module capability
is cauing more trouble than it is worth."
This was done over 5y ago, and Daniel adds that:
...the modular support has been removed from almost all the cpuidle
drivers and the cpuidle framework is no longer assuming driver could
be unloaded.
Removing the modular dead code in the driver makes sense as this
what have been done in the others drivers.
So lets remove the modular code that is essentially orphaned, so that
when reading the driver there is no doubt it is builtin-only.
Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit. At a
later date we might want to consider whether subsys_init or another
init category seems more appropriate than device_init.
We replace module.h with moduleparam.h since the file does declare
some module parameters, and leaving them as such is currently the
easiest way to remain compatible with existing boot arg use cases.
Note that MODULE_DEVICE_TABLE is a no-op for non-modular code.
Also note that we can't remove intel_idle_cpuidle_devices_uninit() as
that is still used for unwind purposes if the init fails.
We also delete the MODULE_LICENSE tag etc. since all that information
is already contained at the top of the file in the comments.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Broxton has all the HSW C-states, except C3.
BXT C-state timing is slightly different.
Here we trust the IRTL MSRs as authority
on maximum C-state latency, and override the driver's tables
with the values found in the associated IRTL MSRs.
Further we set the target_residency to 1x maximum latency,
trusting the hardware demotion logic.
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This driver registers cpuidle devices when a CPU comes online, but it
leaves the registrations in place when a CPU goes offline. The module
exit code only unregisters the currently online CPUs, leaving the
devices for offline CPUs dangling.
This patch changes the driver to clean up all registrations on exit,
even those from CPUs that are offline.
Signed-off-by: Richard Cochran <rcochran@linutronix.de>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
If a cpuidle registration error occurs during the hot plug notifier
callback, we should really inform the hot plug machinery instead of
just ignoring the error. This patch changes the callback to properly
return on error.
Signed-off-by: Richard Cochran <rcochran@linutronix.de>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The helper function, intel_idle_cpu_init, registers one new device
with the cpuidle layer. If the registration should fail, that
function immediately calls intel_idle_cpuidle_devices_uninit() to
unregister every last CPU's device. However, it makes no sense to do
so, when called from the hot plug notifier callback.
This patch moves the call to intel_idle_cpuidle_devices_uninit()
outside of the helper function to the one call site that actually
needs to perform the de-registrations.
Signed-off-by: Richard Cochran <rcochran@linutronix.de>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This driver sets the broadcast tick quite early on during probe and does
not clean up again in cast of failure. This patch moves the setup call
after the registration, placing the on_each_cpu() calls within the global
CPU lock region.
Signed-off-by: Richard Cochran <rcochran@linutronix.de>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The helper function, intel_idle_cpuidle_devices_uninit, frees the
globally allocated per-CPU data. However, this function is invoked
from the hot plug notifier callback at a time when freeing that data
is not safe.
If the call to cpuidle_register_driver() should fail (say, due to lack
of memory), then the driver will free its per-CPU region. On the
*next* CPU_ONLINE event, the driver will happily use the region again
and even free it again if the failure repeats.
This patch fixes the issue by moving the call to free_percpu() outside
of the helper function at the two call sites that actually need to
free the per-CPU data.
Signed-off-by: Richard Cochran <rcochran@linutronix.de>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In the module_init() method, if the per-CPU allocation fails, then the
active cpuidle registration is not cleaned up. This patch fixes the
issue by attempting the allocation before registration, and then
cleaning it up again on registration failure.
Signed-off-by: Richard Cochran <rcochran@linutronix.de>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In the module_exit() method, this driver first frees its per-CPU
pointer, then unregisters a callback making use of the pointer.
Furthermore, the function, intel_idle_cpuidle_devices_uninit, is racy
against CPU hot plugging as it calls for_each_online_cpu().
This patch corrects the issues by unregistering first on the exit path
while holding the hot plug lock.
Signed-off-by: Richard Cochran <rcochran@linutronix.de>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The function, intel_idle_cpuidle_driver_init, makes calls on each CPU
to auto_demotion_disable() and c1e_promotion_disable(). These calls
are redundant, as intel_idle_cpu_init() does the same calls just a bit
later on. They are also premature, as the driver registration may yet
fail.
This patch removes the redundant code.
Signed-off-by: Richard Cochran <rcochran@linutronix.de>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The function, intel_idle_cpuidle_driver_init, delivers no error codes
at all. This patch changes the function to return 'void' instead of
returning zero.
Signed-off-by: Richard Cochran <rcochran@linutronix.de>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Some SKL-H configurations require "intel_idle.max_cstate=7" to boot.
While that is an effective workaround, it disables C10.
This patch detects the problematic configuration,
and disables C8 and C9, keeping C10 enabled.
Note that enabling SGX in BIOS SETUP can also prevent this issue,
if the system BIOS provides that option.
https://bugzilla.kernel.org/show_bug.cgi?id=109081
"Freezes with Intel i7 6700HQ (Skylake), unless intel_idle.max_cstate=7"
Signed-off-by: Len Brown <len.brown@intel.com>
Cc: stable@vger.kernel.org
Skylake Client CPU idle Power states (C-states)
are similar to the previous generation, Broadwell.
However, Skylake does get its own table with updated
worst-case latency and average energy-break-even residency values.
Signed-off-by: Len Brown <len.brown@intel.com>
intel_idle uses a NULL "enter" field in a cpuidle state
to recognize the invalid entry terminating a variable-length array.
Linux-4.0 added support for the system-wide "freeze" state
in cpuidle drivers via the new "enter_freeze" field.
The natural way to expose a deep idle state for freeze,
but not for run-time idle is to supply "enter_freeze" without "enter";
so we update the driver to accept such states.
Signed-off-by: Len Brown <len.brown@intel.com>
Linus Torvalds
Jan Beulich
Dave Hansen
Jacob Pan
Paul Gortmaker
Len Brown
Richard Cochran
Dasaratharaman Chandramouli