If "capacity-dmips-mhz" is not set, raw_capacity is null and we skip the
normalization step which includes setting per_cpu capacity_freq_ref.
Always register the notifier but skip the capacity normalization if
raw_capacity is null.
Fixes: 9942cb22ea ("sched/topology: Add a new arch_scale_freq_ref() method")
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Pierre Gondois <pierre.gondois@arm.com>
Tested-by: Mark Brown <broonie@kernel.org>
Tested-by: Paul Barker <paul.barker.ct@bp.renesas.com>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Link: https://lore.kernel.org/r/20240117190545.596057-1-vincent.guittot@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Here are the set of driver core and kernfs changes for 6.8-rc1. Nothing
major in here this release cycle, just lots of small cleanups and some
tweaks on kernfs that in the very end, got reverted and will come back
in a safer way next release cycle.
Included in here are:
- more driver core 'const' cleanups and fixes
- fw_devlink=rpm is now the default behavior
- kernfs tiny changes to remove some string functions
- cpu handling in the driver core is updated to work better on many
systems that add topologies and cpus after booting
- other minor changes and cleanups
All of the cpu handling patches have been acked by the respective
maintainers and are coming in here in one series. Everything has been
in linux-next for a while with no reported issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
"Here are the set of driver core and kernfs changes for 6.8-rc1.
Nothing major in here this release cycle, just lots of small cleanups
and some tweaks on kernfs that in the very end, got reverted and will
come back in a safer way next release cycle.
Included in here are:
- more driver core 'const' cleanups and fixes
- fw_devlink=rpm is now the default behavior
- kernfs tiny changes to remove some string functions
- cpu handling in the driver core is updated to work better on many
systems that add topologies and cpus after booting
- other minor changes and cleanups
All of the cpu handling patches have been acked by the respective
maintainers and are coming in here in one series. Everything has been
in linux-next for a while with no reported issues"
* tag 'driver-core-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (51 commits)
Revert "kernfs: convert kernfs_idr_lock to an irq safe raw spinlock"
kernfs: convert kernfs_idr_lock to an irq safe raw spinlock
class: fix use-after-free in class_register()
PM: clk: make pm_clk_add_notifier() take a const pointer
EDAC: constantify the struct bus_type usage
kernfs: fix reference to renamed function
driver core: device.h: fix Excess kernel-doc description warning
driver core: class: fix Excess kernel-doc description warning
driver core: mark remaining local bus_type variables as const
driver core: container: make container_subsys const
driver core: bus: constantify subsys_register() calls
driver core: bus: make bus_sort_breadthfirst() take a const pointer
kernfs: d_obtain_alias(NULL) will do the right thing...
driver core: Better advertise dev_err_probe()
kernfs: Convert kernfs_path_from_node_locked() from strlcpy() to strscpy()
kernfs: Convert kernfs_name_locked() from strlcpy() to strscpy()
kernfs: Convert kernfs_walk_ns() from strlcpy() to strscpy()
initramfs: Expose retained initrd as sysfs file
fs/kernfs/dir: obey S_ISGID
kernel/cgroup: use kernfs_create_dir_ns()
...
Use the new capacity_ref_freq() method to set the ratio that is used by AMU for
computing the arch_scale_freq_capacity().
This helps to keep everything aligned using the same reference for
computing CPUs capacity.
The default value of the ratio (stored in per_cpu(arch_max_freq_scale))
ensures that arch_scale_freq_capacity() returns max capacity until it is
set to its correct value with the cpu capacity and capacity_ref_freq().
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20231211104855.558096-8-vincent.guittot@linaro.org
Save the frequency associated to the performance that has been used when
initializing the capacity of CPUs.
Also, cppc cpufreq driver can register an artificial energy model. In such
case, it needs the frequency for this compute capacity.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Pierre Gondois <pierre.gondois@arm.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://lore.kernel.org/r/20231211104855.558096-7-vincent.guittot@linaro.org
Create a new method to get a unique and fixed max frequency. Currently
cpuinfo.max_freq or the highest (or last) state of performance domain are
used as the max frequency when computing the frequency for a level of
utilization, but:
- cpuinfo_max_freq can change at runtime. boost is one example of
such change.
- cpuinfo.max_freq and last item of the PD can be different leading to
different results between cpufreq and energy model.
We need to save the reference frequency that has been used when computing
the CPUs capacity and use this fixed and coherent value to convert between
frequency and CPU's capacity.
In fact, we already save the frequency that has been used when computing
the capacity of each CPU. We extend the precision to save kHz instead of
MHz currently and we modify the type to be aligned with other variables
used when converting frequency to capacity and the other way.
[ mingo: Minor edits. ]
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Lukasz Luba <lukasz.luba@arm.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Link: https://lore.kernel.org/r/20231211104855.558096-2-vincent.guittot@linaro.org
register_cpu_capacity_sysctl() adds a property to sysfs that describes
the CPUs capacity. This is done from a subsys_initcall() that assumes
all possible CPUs are registered.
With CPU hotplug, possible CPUs aren't registered until they become
present, (or for arm64 enabled). This leads to messages during boot:
| register_cpu_capacity_sysctl: too early to get CPU1 device!
and once these CPUs are added to the system, the file is missing.
Move this to a cpuhp callback, so that the file is created once
CPUs are brought online. This covers CPUs that are added late by
mechanisms like hotplug.
One observable difference is the file is now missing for offline CPUs.
Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: "Russell King (Oracle)" <rmk+kernel@armlinux.org.uk>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/E1r5R2g-00CsyV-Ss@rmk-PC.armlinux.org.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fetch_cache_info() tries to get the number of cache leaves/levels
for each CPU in order to pre-allocate memory for cacheinfo struct.
Allocating this memory later triggers a:
'BUG: sleeping function called from invalid context'
in PREEMPT_RT kernels.
If there is no cache related information available in DT or ACPI,
fetch_cache_info() fails and an error message is printed:
'Early cacheinfo failed, ret = ...'
Not having cache information should be a valid configuration.
Remove the error message if fetch_cache_info() fails with -ENOENT.
Suggested-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/all/20230404-hatred-swimmer-6fecdf33b57a@spud/
Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230414081453.244787-4-pierre.gondois@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Recent work enables cacheinfo memory for secondary CPUs to be allocated
early, while still running on the primary CPU. That allows cacheinfo
memory to be allocated safely on RT kernels. To make that work, the
number of cache levels/leaves must be defined in the device tree or ACPI
tables. Further work adds a path for early detection of the number of
cache levels/leaves, which makes it possible to allocate the cacheinfo
memory early without requiring extra DT/ACPI information.
This patch addresses a specific issue with ACPI systems with no PPTT. In
that case, parse_acpi_topology() returns an error code, which in turn
makes init_cpu_topology() return early, before fetch_cache_info() is
called. In that case, the early cache level detection doesn't run.
The solution is to simply remove the "return" statement and let the code
flow fall through to calling fetch_cache_info().
Signed-off-by: Radu Rendec <rrendec@redhat.com>
Reported-by: Pierre Gondois <pierre.gondois@arm.com>
Link: https://lore.kernel.org/all/dea94484-797f-3034-7b86-6d88801c0d91@arm.com/
Reviewed-by: Pierre Gondois <pierre.gondois@arm.com>
Link: https://lore.kernel.org/r/20230412185759.755408-4-rrendec@redhat.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
commit 3fcbf1c77d ("arch_topology: Fix cache attributes detection
in the CPU hotplug path")
adds a call to detect_cache_attributes() to populate the cacheinfo
before updating the siblings mask. detect_cache_attributes() allocates
memory and can take the PPTT mutex (on ACPI platforms). On PREEMPT_RT
kernels, on secondary CPUs, this triggers a:
'BUG: sleeping function called from invalid context' [1]
as the code is executed with preemption and interrupts disabled.
The primary CPU was previously storing the cache information using
the now removed (struct cpu_topology).llc_id:
commit 5b8dc787ce ("arch_topology: Drop LLC identifier stash from
the CPU topology")
allocate_cache_info() tries to build the cacheinfo from the primary
CPU prior secondary CPUs boot, if the DT/ACPI description
contains cache information.
If allocate_cache_info() fails, then fallback to the current state
for the cacheinfo allocation. [1] will be triggered in such case.
When unplugging a CPU, the cacheinfo memory cannot be freed. If it
was, then the memory would be allocated early by the re-plugged
CPU and would trigger [1].
Note that populate_cache_leaves() might be called multiple times
due to populate_leaves being moved up. This is required since
detect_cache_attributes() might be called with per_cpu_cacheinfo(cpu)
being allocated but not populated.
[1]:
| BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:46
| in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: 0, name: swapper/111
| preempt_count: 1, expected: 0
| RCU nest depth: 1, expected: 1
| 3 locks held by swapper/111/0:
| #0: (&pcp->lock){+.+.}-{3:3}, at: get_page_from_freelist+0x218/0x12c8
| #1: (rcu_read_lock){....}-{1:3}, at: rt_spin_trylock+0x48/0xf0
| #2: (&zone->lock){+.+.}-{3:3}, at: rmqueue_bulk+0x64/0xa80
| irq event stamp: 0
| hardirqs last enabled at (0): 0x0
| hardirqs last disabled at (0): copy_process+0x5dc/0x1ab8
| softirqs last enabled at (0): copy_process+0x5dc/0x1ab8
| softirqs last disabled at (0): 0x0
| Preemption disabled at:
| migrate_enable+0x30/0x130
| CPU: 111 PID: 0 Comm: swapper/111 Tainted: G W 6.0.0-rc4-rt6-[...]
| Call trace:
| __kmalloc+0xbc/0x1e8
| detect_cache_attributes+0x2d4/0x5f0
| update_siblings_masks+0x30/0x368
| store_cpu_topology+0x78/0xb8
| secondary_start_kernel+0xd0/0x198
| __secondary_switched+0xb0/0xb4
Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Link: https://lore.kernel.org/r/20230104183033.755668-7-pierre.gondois@arm.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
* Improvements to the CPU topology subsystem, which fix some issues
where RISC-V would report bad topology information.
* The default NR_CPUS has increased to XLEN, and the maximum
configurable value is 512.
* The CD-ROM filesystems have been enabled in the defconfig.
* Support for THP_SWAP has been added for rv64 systems.
There are also a handful of cleanups and fixes throughout the tree.
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Merge tag 'riscv-for-linus-6.1-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V updates from Palmer Dabbelt:
- Improvements to the CPU topology subsystem, which fix some issues
where RISC-V would report bad topology information.
- The default NR_CPUS has increased to XLEN, and the maximum
configurable value is 512.
- The CD-ROM filesystems have been enabled in the defconfig.
- Support for THP_SWAP has been added for rv64 systems.
There are also a handful of cleanups and fixes throughout the tree.
* tag 'riscv-for-linus-6.1-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: enable THP_SWAP for RV64
RISC-V: Print SSTC in canonical order
riscv: compat: s/failed/unsupported if compat mode isn't supported
RISC-V: Increase range and default value of NR_CPUS
cpuidle: riscv-sbi: Fix CPU_PM_CPU_IDLE_ENTER_xyz() macro usage
perf: RISC-V: throttle perf events
perf: RISC-V: exclude invalid pmu counters from SBI calls
riscv: enable CD-ROM file systems in defconfig
riscv: topology: fix default topology reporting
arm64: topology: move store_cpu_topology() to shared code
Merge new material related to CPPC, PCC, APEI and OSI strings handling
for 6.1-rc1:
- Disable frequency invariance in the CPPC library if registers used
by cppc_get_perf_ctrs() are accessed via PCC (Jeremy Linton).
- Add ACPI disabled check to acpi_cpc_valid() (Perry Yuan).
- Fix Tx acknowledge in the PCC address space handler (Huisong Li).
- Use wait_for_completion_timeout() for PCC mailbox operations (Huisong
Li).
- Release resources on PCC address space setup failure path (Rafael
Mendonca).
- Remove unneeded result variables from APEI code (ye xingchen).
- Print total number of records found during BERT log parsing (Dmitry
Monakhov).
- Drop support for 3 _OSI strings that should not be necessary any
more and update documentation on custom _OSI strings so that adding
new ones is not encouraged any more (Mario Limonciello).
* acpi-cppc:
ACPI: CPPC: Disable FIE if registers in PCC regions
ACPI: CPPC: Add ACPI disabled check to acpi_cpc_valid()
* acpi-pcc:
ACPI: PCC: Fix Tx acknowledge in the PCC address space handler
ACPI: PCC: replace wait_for_completion()
ACPI: PCC: Release resources on address space setup failure path
* acpi-apei:
ACPI: APEI: Remove unneeded result variables
ACPI: APEI: Add BERT error log footer
* acpi-osi:
ACPI: OSI: Update Documentation on custom _OSI strings
ACPI: OSI: Remove Linux-HPI-Hybrid-Graphics _OSI string
ACPI: OSI: Remove Linux-Lenovo-NV-HDMI-Audio _OSI string
ACPI: OSI: Remove Linux-Dell-Video _OSI string
Currently cpu_clustergroup_mask() will return CPU mask if cluster span more
or the same CPUs as cpu_coregroup_mask(). This will result topology borken
on non-Cluster SMT machines when building with CONFIG_SCHED_CLUSTER=y.
Test with:
qemu-system-aarch64 -enable-kvm -machine virt \
-net none \
-cpu host \
-bios ./QEMU_EFI.fd \
-m 2G \
-smp 48,sockets=2,cores=12,threads=2 \
-kernel $Image \
-initrd $Rootfs \
-nographic
-append "rdinit=init console=ttyAMA0 sched_verbose loglevel=8"
We'll get below error:
[ 3.084568] BUG: arch topology borken
[ 3.084570] the SMT domain not a subset of the CLS domain
Since cluster is a level higher than SMT, fix this by making cluster
spans at least SMT CPUs.
Fixes: bfcc439743 ("arch_topology: Limit span of cpu_clustergroup_mask()")
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Ionela Voinescu <ionela.voinescu@arm.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
Link: https://lore.kernel.org/r/20220905122615.12946-1-yangyicong@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 6b66ca0bac as it
breaks the build on some arches as reported by the kernel test robot.
Link: https://lore.kernel.org/r/202209030824.SouwDV5M-lkp@intel.com
Reported-by: kernel test robot <lkp@intel.com>
Fixes: 6b66ca0bac ("arch_topology: Make cluster topology span at least SMT CPUs")
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Ionela Voinescu <ionela.voinescu@arm.com>
Cc: Yicong Yang <yangyicong@hisilicon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently cpu_clustergroup_mask() will return CPU mask if cluster span more
or the same CPUs as cpu_coregroup_mask(). This will result topology borken
on non-Cluster SMT machines when building with CONFIG_SCHED_CLUSTER=y.
Test with:
qemu-system-aarch64 -enable-kvm -machine virt \
-net none \
-cpu host \
-bios ./QEMU_EFI.fd \
-m 2G \
-smp 48,sockets=2,cores=12,threads=2 \
-kernel $Image \
-initrd $Rootfs \
-nographic \
-append "rdinit=init console=ttyAMA0 sched_verbose loglevel=8"
We'll get below error:
[ 3.084568] BUG: arch topology borken
[ 3.084570] the SMT domain not a subset of the CLS domain
Since cluster is a level higher than SMT, fix this by making cluster
spans at least SMT CPUs.
Fixes: bfcc439743 ("arch_topology: Limit span of cpu_clustergroup_mask()")
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Ionela Voinescu <ionela.voinescu@arm.com>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Reviewed-by: Ionela Voinescu <ionela.voinescu@arm.com>
Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
Link: https://lore.kernel.org/r/20220825092007.8129-1-yangyicong@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Architectures which do not have cacheinfo such as ARM 32-bit would spit
out the following during boot:
Early cacheinfo failed, ret = -2
Treat -ENOENT specifically to silence this error since it means that the
platform does not support reporting its cache information.
Fixes: 3fcbf1c77d ("arch_topology: Fix cache attributes detection in the CPU hotplug path")
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Michael Walle <michael@walle.cc>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/20220805230736.1562801-1-f.fainelli@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make acpi_cpc_valid() check if ACPI is disabled, so that its callers
don't need to check that separately. This will also cause the AMD
pstate driver to refuse to load right away when ACPI is disabled.
Also update the warning message in amd_pstate_init() to mention the
ACPI disabled case for completeness.
Signed-off-by: Perry Yuan <Perry.Yuan@amd.com>
[ rjw: Subject edits, new changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
arm64's method of defining a default cpu topology requires only minimal
changes to apply to RISC-V also. The current arm64 implementation exits
early in a uniprocessor configuration by reading MPIDR & claiming that
uniprocessor can rely on the default values.
This is appears to be a hangover from prior to '3102bc0e6ac7 ("arm64:
topology: Stop using MPIDR for topology information")', because the
current code just assigns default values for multiprocessor systems.
With the MPIDR references removed, store_cpu_topolgy() can be moved to
the common arch_topology code.
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
init_cpu_topology() is called only once at the boot and all the cache
attributes are detected early for all the possible CPUs. However when
the CPUs are hotplugged out, the cacheinfo gets removed. While the
attributes are added back when the CPUs are hotplugged back in as part
of CPU hotplug state machine, it ends up called quite late after the
update_siblings_masks() are called in the secondary_start_kernel()
resulting in wrong llc_sibling_masks.
Move the call to detect_cache_attributes() inside update_siblings_masks()
to ensure the cacheinfo is updated before the LLC sibling masks are
updated. This will fix the incorrect LLC sibling masks generated when
the CPUs are hotplugged out and hotplugged back in again.
Reported-by: Ionela Voinescu <ionela.voinescu@arm.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Ionela Voinescu <ionela.voinescu@arm.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Ionela Voinescu <ionela.voinescu@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Link: https://lore.kernel.org/r/20220720-arch_topo_fixes-v3-3-43d696288e84@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We don't support the topology for clusters of CPU clusters while the
DT and ACPI bindings theoritcally support the same. Just warn about the
same so that it is clear to the users of arch_topology that the nested
clusters are not yet supported.
Link: https://lore.kernel.org/r/20220704101605.1318280-21-sudeep.holla@arm.com
Tested-by: Ionela Voinescu <ionela.voinescu@arm.com>
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Finally let us add support for socket nodes in /cpu-map in the device
tree. Since this may not be present in all the old platforms and even
most of the existing platforms, we need to assume absence of the socket
node indicates that it is a single socket system and handle appropriately.
Also it is likely that most single socket systems skip to as the node
since it is optional.
Link: https://lore.kernel.org/r/20220704101605.1318280-20-sudeep.holla@arm.com
Tested-by: Ionela Voinescu <ionela.voinescu@arm.com>
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Ionela Voinescu <ionela.voinescu@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Let us set the cluster identifier as parsed from the device tree
cluster nodes within /cpu-map.
We don't support nesting of clusters yet as there are no real hardware
to support clusters of clusters.
Link: https://lore.kernel.org/r/20220704101605.1318280-19-sudeep.holla@arm.com
Tested-by: Ionela Voinescu <ionela.voinescu@arm.com>
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Ionela Voinescu <ionela.voinescu@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Currently the cluster identifier is not set on DT based platforms.
The reset or default value is -1 for all the CPUs. Once we assign the
cluster identifier values correctly, the cluster_sibling mask will be
populated and returned by cpu_clustergroup_mask() to contribute in the
creation of the CLS scheduling domain level, if SCHED_CLUSTER is
enabled.
To avoid topologies that will result in questionable or incorrect
scheduling domains, impose restrictions regarding the span of clusters,
as presented to scheduling domains building code: cluster_sibling should
not span more or the same CPUs as cpu_coregroup_mask().
This is needed in order to obtain a strict separation between the MC and
CLS levels, and maintain the same domains for existing platforms in
the presence of CONFIG_SCHED_CLUSTER, where the new cluster information
is redundant and irrelevant for the scheduler.
While previously the scheduling domain builder code would have removed MC
as redundant and kept CLS if SCHED_CLUSTER was enabled and the
cpu_coregroup_mask() and cpu_clustergroup_mask() spanned the same CPUs,
now CLS will be removed and MC kept.
Link: https://lore.kernel.org/r/20220704101605.1318280-18-sudeep.holla@arm.com
Cc: Darren Hart <darren@os.amperecomputing.com>
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Acked-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Currently as we parse the CPU topology from /cpu-map node from the
device tree, we assign generated cluster count as the physical package
identifier for each CPU which is wrong.
The device tree bindings for CPU topology supports sockets to infer
the socket or physical package identifier for a given CPU. Since it is
fairly new and not supported on most of the old and existing systems, we
can assume all such systems have single socket/physical package.
Fix the physical package identifier to 0 by removing the assignment of
cluster identifier to the same.
Link: https://lore.kernel.org/r/20220704101605.1318280-17-sudeep.holla@arm.com
Tested-by: Ionela Voinescu <ionela.voinescu@arm.com>
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Ionela Voinescu <ionela.voinescu@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
There is no point in looping through all the CPU's physical package
identifier to check if it is valid or not once a CPU which is outside
the topology(i.e. outlier CPU) is found.
Let us just break out of the loop early in such case.
Link: https://lore.kernel.org/r/20220704101605.1318280-16-sudeep.holla@arm.com
Tested-by: Ionela Voinescu <ionela.voinescu@arm.com>
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Instead of just comparing the cpu topology IDs with -1 to check their
validity, improve that by checking for a valid non-negative value.
Link: https://lore.kernel.org/r/20220704101605.1318280-15-sudeep.holla@arm.com
Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Tested-by: Ionela Voinescu <ionela.voinescu@arm.com>
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Currently the cluster identifier is not set on the DT based platforms.
The reset or default value is -1 for all the CPUs. Once we assign the
cluster identifier values correctly that may result in getting the thread
siblings wrong as the core identifiers can be same for 2 different CPUs
belonging to 2 different cluster.
So, in order to get the thread sibling cpumasks correct, we need to
update them only if the cores they belong are in the same cluster within
the socket. Let us skip updation of the thread sibling cpumaks if the
cluster identifier doesn't match.
This change won't affect even if the cluster identifiers are not set
currently but will avoid any breakage once we set the same correctly.
Link: https://lore.kernel.org/r/20220704101605.1318280-14-sudeep.holla@arm.com
Tested-by: Gavin Shan <gshan@redhat.com>
Tested-by: Ionela Voinescu <ionela.voinescu@arm.com>
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Since the cacheinfo LLC information is used directly in arch_topology,
there is no need to parse and store the LLC ID information only for
ACPI systems in the CPU topology.
Remove the redundant LLC ID from the generic CPU arch_topology
information.
Link: https://lore.kernel.org/r/20220704101605.1318280-13-sudeep.holla@arm.com
Tested-by: Ionela Voinescu <ionela.voinescu@arm.com>
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
The cacheinfo is now initialised early along with the CPU topology
initialisation. Instead of relying on the LLC ID information parsed
separately only with ACPI PPTT elsewhere, migrate to use the similar
information from the cacheinfo.
This is generic for both DT and ACPI systems. The ACPI LLC ID information
parsed separately can now be removed from arch specific code.
Link: https://lore.kernel.org/r/20220704101605.1318280-11-sudeep.holla@arm.com
Tested-by: Ionela Voinescu <ionela.voinescu@arm.com>
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Currently ACPI populates just the minimum information about the last
level cache from PPTT in order to feed the same to build sched_domains.
Similar support for DT platforms is not present.
In order to enable the same, the entire cache hierarchy information can
be built as part of CPU topoplogy parsing both on ACPI and DT platforms.
Note that this change builds the cacheinfo early even on ACPI systems,
but the current mechanism of building llc_sibling mask remains unchanged.
Link: https://lore.kernel.org/r/20220704101605.1318280-10-sudeep.holla@arm.com
Tested-by: Ionela Voinescu <ionela.voinescu@arm.com>
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Add trace event to capture the moment of the call for updating the thermal
pressure value. It's helpful to investigate how often those events occur
in a system dealing with throttling. This trace event is needed since the
old 'cdev_update' might not be used by some drivers.
The old 'cdev_update' trace event only provides a cooling state
value: [0, n]. That state value then needs additional tools to translate
it: state -> freq -> capacity -> thermal pressure. This new trace event
just stores proper thermal pressure value in the trace buffer, no need
for additional logic. This is helpful for cooperation when someone can
simply sends to the list the trace buffer output from the platform (no
need from additional information from other subsystems).
There are also platforms which due to some design reasons don't use
cooling devices and thus don't trigger old 'cdev_update' trace event.
They are also important and measuring latency for the thermal signal
raising/decaying characteristics is in scope. This new trace event
would cover them as well.
We already have a trace point 'pelt_thermal_tp' which after a change to
trace event can be paired with this new 'thermal_pressure_update' and
derive more insight what is going on in the system under thermal pressure
(and why).
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Link: https://lore.kernel.org/r/20220427080806.1906-1-lukasz.luba@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When ACPI is not enabled, cpuid_topo->llc_id = cpu_topo->llc_id = -1, which
will set llc_sibling 0xff(...), this is misleading.
Don't set llc_sibling(default 0) if we don't know the cache topology.
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Wang Qing <wangqing@vivo.com>
Fixes: 37c3ec2d81 ("arm64: topology: divorce MC scheduling domain from core_siblings")
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/1649644580-54626-1-git-send-email-wangqing@vivo.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ampere Altra defines CPU clusters in the ACPI PPTT. They share a Snoop
Control Unit, but have no shared CPU-side last level cache.
cpu_coregroup_mask() will return a cpumask with weight 1, while
cpu_clustergroup_mask() will return a cpumask with weight 2.
As a result, build_sched_domain() will BUG() once per CPU with:
BUG: arch topology borken
the CLS domain not a subset of the MC domain
The MC level cpumask is then extended to that of the CLS child, and is
later removed entirely as redundant. This sched domain topology is an
improvement over previous topologies, or those built without
SCHED_CLUSTER, particularly for certain latency sensitive workloads.
With the current scheduler model and heuristics, this is a desirable
default topology for Ampere Altra and Altra Max system.
Rather than create a custom sched domains topology structure and
introduce new logic in arch/arm64 to detect these systems, update the
core_mask so coregroup is never a subset of clustergroup, extending it
to cluster_siblings if necessary. Only do this if CONFIG_SCHED_CLUSTER
is enabled to avoid also changing the topology (MC) when
CONFIG_SCHED_CLUSTER is disabled.
This has the added benefit over a custom topology of working for both
symmetric and asymmetric topologies. It does not address systems where
the CLUSTER topology is above a populated MC topology, but these are not
considered today and can be addressed separately if and when they
appear.
The final sched domain topology for a 2 socket Ampere Altra system is
unchanged with or without CONFIG_SCHED_CLUSTER, and the BUG is avoided:
For CPU0:
CONFIG_SCHED_CLUSTER=y
CLS [0-1]
DIE [0-79]
NUMA [0-159]
CONFIG_SCHED_CLUSTER is not set
DIE [0-79]
NUMA [0-159]
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: D. Scott Phillips <scott@os.amperecomputing.com>
Cc: Ilkka Koskinen <ilkka@os.amperecomputing.com>
Cc: <stable@vger.kernel.org> # 5.16.x
Suggested-by: Barry Song <song.bao.hua@hisilicon.com>
Reviewed-by: Barry Song <song.bao.hua@hisilicon.com>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Darren Hart <darren@os.amperecomputing.com>
Link: https://lore.kernel.org/r/c8fe9fce7c86ed56b4c455b8c902982dc2303868.1649696956.git.darren@os.amperecomputing.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Define topology_init_cpu_capacity_cppc() to use highest performance
values from _CPC objects to obtain and set maximum capacity information
for each CPU. acpi_cppc_processor_probe() is a good point at which to
trigger the initialization of CPU (u-arch) capacity values, as at this
point the highest performance values can be obtained from each CPU's
_CPC objects. Architectures can therefore use this functionality
through arch_init_invariance_cppc().
The performance scale used by CPPC is a unified scale for all CPUs in
the system. Therefore, by obtaining the raw highest performance values
from the _CPC objects, and normalizing them on the [0, 1024] capacity
scale, used by the task scheduler, we obtain the CPU capacity of each
CPU.
While an ACPI Notify(0x85) could alert about a change in the highest
performance value, which should in turn retrigger the CPU capacity
computations, this notification is not currently handled by the ACPI
processor driver. When supported, a call to arch_init_invariance_cppc()
would perform the update.
Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
Tested-by: Yicong Yang <yangyicong@hisilicon.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
There is no need of this function (and related) since code has been
converted to use the new arch_update_thermal_pressure() API. The old
code can be removed.
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
The thermal pressure is a mechanism which is used for providing
information about reduced CPU performance to the scheduler. Usually code
has to convert the value from frequency units into capacity units,
which are understandable by the scheduler. Create a common conversion code
which can be just used via a handy API.
Internally, the topology_update_thermal_pressure() operates on frequency
in MHz and max CPU frequency is taken from 'freq_factor' (per-cpu).
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Reviewed-by: Thara Gopinath <thara.gopinath@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Here is the big set of driver core changes for 5.16-rc1.
All of these have been in linux-next for a while now with no reported
problems.
Included in here are:
- big update and cleanup of the sysfs abi documentation files
and scripts from Mauro. We are almost at the place where we
can properly check that the running kernel's sysfs abi is
documented fully.
- firmware loader updates
- dyndbg updates
- kernfs cleanups and fixes from Christoph
- device property updates
- component fix
- other minor driver core cleanups and fixes
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
"Here is the big set of driver core changes for 5.16-rc1.
All of these have been in linux-next for a while now with no reported
problems.
Included in here are:
- big update and cleanup of the sysfs abi documentation files and
scripts from Mauro. We are almost at the place where we can
properly check that the running kernel's sysfs abi is documented
fully.
- firmware loader updates
- dyndbg updates
- kernfs cleanups and fixes from Christoph
- device property updates
- component fix
- other minor driver core cleanups and fixes"
* tag 'driver-core-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (122 commits)
device property: Drop redundant NULL checks
x86/build: Tuck away built-in firmware under FW_LOADER
vmlinux.lds.h: wrap built-in firmware support under FW_LOADER
firmware_loader: move struct builtin_fw to the only place used
x86/microcode: Use the firmware_loader built-in API
firmware_loader: remove old DECLARE_BUILTIN_FIRMWARE()
firmware_loader: formalize built-in firmware API
component: do not leave master devres group open after bind
dyndbg: refine verbosity 1-4 summary-detail
gpiolib: acpi: Replace custom code with device_match_acpi_handle()
i2c: acpi: Replace custom function with device_match_acpi_handle()
driver core: Provide device_match_acpi_handle() helper
dyndbg: fix spurious vNpr_info change
dyndbg: no vpr-info on empty queries
dyndbg: vpr-info on remove-module complete, not starting
device property: Add missed header in fwnode.h
Documentation: dyndbg: Improve cli param examples
dyndbg: Remove support for ddebug_query param
dyndbg: make dyndbg a known cli param
dyndbg: show module in vpr-info in dd-exec-queries
...
Both ACPI and DT provide the ability to describe additional layers of
topology between that of individual cores and higher level constructs
such as the level at which the last level cache is shared.
In ACPI this can be represented in PPTT as a Processor Hierarchy
Node Structure [1] that is the parent of the CPU cores and in turn
has a parent Processor Hierarchy Nodes Structure representing
a higher level of topology.
For example Kunpeng 920 has 6 or 8 clusters in each NUMA node, and each
cluster has 4 cpus. All clusters share L3 cache data, but each cluster
has local L3 tag. On the other hand, each clusters will share some
internal system bus.
+-----------------------------------+ +---------+
| +------+ +------+ +--------------------------+ |
| | CPU0 | | cpu1 | | +-----------+ | |
| +------+ +------+ | | | | |
| +----+ L3 | | |
| +------+ +------+ cluster | | tag | | |
| | CPU2 | | CPU3 | | | | | |
| +------+ +------+ | +-----------+ | |
| | | |
+-----------------------------------+ | |
+-----------------------------------+ | |
| +------+ +------+ +--------------------------+ |
| | | | | | +-----------+ | |
| +------+ +------+ | | | | |
| | | L3 | | |
| +------+ +------+ +----+ tag | | |
| | | | | | | | | |
| +------+ +------+ | +-----------+ | |
| | | |
+-----------------------------------+ | L3 |
| data |
+-----------------------------------+ | |
| +------+ +------+ | +-----------+ | |
| | | | | | | | | |
| +------+ +------+ +----+ L3 | | |
| | | tag | | |
| +------+ +------+ | | | | |
| | | | | | +-----------+ | |
| +------+ +------+ +--------------------------+ |
+-----------------------------------| | |
+-----------------------------------| | |
| +------+ +------+ +--------------------------+ |
| | | | | | +-----------+ | |
| +------+ +------+ | | | | |
| +----+ L3 | | |
| +------+ +------+ | | tag | | |
| | | | | | | | | |
| +------+ +------+ | +-----------+ | |
| | | |
+-----------------------------------+ | |
+-----------------------------------+ | |
| +------+ +------+ +--------------------------+ |
| | | | | | +-----------+ | |
| +------+ +------+ | | | | |
| | | L3 | | |
| +------+ +------+ +---+ tag | | |
| | | | | | | | | |
| +------+ +------+ | +-----------+ | |
| | | |
+-----------------------------------+ | |
+-----------------------------------+ | |
| +------+ +------+ +--------------------------+ |
| | | | | | +-----------+ | |
| +------+ +------+ | | | | |
| | | L3 | | |
| +------+ +------+ +--+ tag | | |
| | | | | | | | | |
| +------+ +------+ | +-----------+ | |
| | +---------+
+-----------------------------------+
That means spreading tasks among clusters will bring more bandwidth
while packing tasks within one cluster will lead to smaller cache
synchronization latency. So both kernel and userspace will have
a chance to leverage this topology to deploy tasks accordingly to
achieve either smaller cache latency within one cluster or an even
distribution of load among clusters for higher throughput.
This patch exposes cluster topology to both kernel and userspace.
Libraried like hwloc will know cluster by cluster_cpus and related
sysfs attributes. PoC of HWLOC support at [2].
Note this patch only handle the ACPI case.
Special consideration is needed for SMT processors, where it is
necessary to move 2 levels up the hierarchy from the leaf nodes
(thus skipping the processor core level).
Note that arm64 / ACPI does not provide any means of identifying
a die level in the topology but that may be unrelate to the cluster
level.
[1] ACPI Specification 6.3 - section 5.2.29.1 processor hierarchy node
structure (Type 0)
[2] https://github.com/hisilicon/hwloc/tree/linux-cluster
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210924085104.44806-2-21cnbao@gmail.com
arch_topology.c hasn't use any macro or function declared in linux/percpu.h,
linux/smp.h and linux/string.h.
Thus, these files can be removed from arch_topology.c safely without
affecting the compilation of the drivers/base/ module
Signed-off-by: Mianhan Liu <liumh1@shanghaitech.edu.cn>
Link: https://lore.kernel.org/r/20210928193138.24192-1-liumh1@shanghaitech.edu.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add interrupt support to notify the kernel of h/w initiated frequency
throttling by LMh. Convey this to scheduler via thermal presssure
interface.
Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org>
[Viresh: Added changes for arch_topology.c to fix build errors ]
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Currently topology_scale_freq_tick() (which gets called from
scheduler_tick()) may end up using a pointer to "struct
scale_freq_data", which was previously cleared by
topology_clear_scale_freq_source(), as there is no protection in place
here. The users of topology_clear_scale_freq_source() though needs a
guarantee that the previously cleared scale_freq_data isn't used
anymore, so they can free the related resources.
Since topology_scale_freq_tick() is called from scheduler tick, we don't
want to add locking in there. Use the RCU update mechanism instead
(which is already used by the scheduler's utilization update path) to
guarantee race free updates here.
synchronize_rcu() makes sure that all RCU critical sections that started
before it is called, will finish before it returns. And so the callers
of topology_clear_scale_freq_source() don't need to worry about their
callback getting called anymore.
Cc: Paul E. McKenney <paulmck@kernel.org>
Fixes: 01e055c120 ("arch_topology: Allow multiple entities to provide sched_freq_tick() callback")
Tested-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Ionela Voinescu <ionela.voinescu@arm.com>
Tested-by: Qian Cai <quic_qiancai@quicinc.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
It is possible now for other parts of the kernel to provide their own
implementation of sched_freq_tick() and they can very well be modules
themselves (like CPPC cpufreq driver, which is going to use these in a
later commit).
Export arch_freq_scale and topology_{set|clear}_scale_freq_source().
Reviewed-by: Ionela Voinescu <ionela.voinescu@arm.com>
Tested-by: Ionela Voinescu <ionela.voinescu@arm.com>
Tested-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
This patch attempts to make it generic enough so other parts of the
kernel can also provide their own implementation of scale_freq_tick()
callback, which is called by the scheduler periodically to update the
per-cpu arch_freq_scale variable.
The implementations now need to provide 'struct scale_freq_data' for the
CPUs for which they have hardware counters available, and a callback
gets registered for each possible CPU in a per-cpu variable.
The arch specific (or ARM AMU) counters are updated to adapt to this and
they take the highest priority if they are available, i.e. they will be
used instead of CPPC based counters for example.
The special code to rebuild the sched domains, in case invariance status
change for the system, is moved out of arm64 specific code and is added
to arch_topology.c.
Note that this also defines SCALE_FREQ_SOURCE_CPUFREQ but doesn't use it
and it is added to show that cpufreq is also acts as source of
information for FIE and will be used by default if no other counters are
supported for a platform.
Reviewed-by: Ionela Voinescu <ionela.voinescu@arm.com>
Tested-by: Ionela Voinescu <ionela.voinescu@arm.com>
Acked-by: Will Deacon <will@kernel.org> # for arm64
Tested-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Rename freq_scale to a less generic name, as it will get exported soon
for modules. Since x86 already names its own implementation of this as
arch_freq_scale, lets stick to that.
Suggested-by: Will Deacon <will@kernel.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Here is the "big" set of driver core patches for 5.10-rc1
They include a lot of different things, all related to the driver core
and/or some driver logic:
- sysfs common write functions to make it easier to audit sysfs
attributes
- device connection cleanups and fixes
- devm helpers for a few functions
- NOIO allocations for when devices are being removed
- minor cleanups and fixes
All have been in linux-next for a while with no reported issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
"Here is the "big" set of driver core patches for 5.10-rc1
They include a lot of different things, all related to the driver core
and/or some driver logic:
- sysfs common write functions to make it easier to audit sysfs
attributes
- device connection cleanups and fixes
- devm helpers for a few functions
- NOIO allocations for when devices are being removed
- minor cleanups and fixes
All have been in linux-next for a while with no reported issues"
* tag 'driver-core-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (31 commits)
regmap: debugfs: use semicolons rather than commas to separate statements
platform/x86: intel_pmc_core: do not create a static struct device
drivers core: node: Use a more typical macro definition style for ACCESS_ATTR
drivers core: Use sysfs_emit for shared_cpu_map_show and shared_cpu_list_show
mm: and drivers core: Convert hugetlb_report_node_meminfo to sysfs_emit
drivers core: Miscellaneous changes for sysfs_emit
drivers core: Reindent a couple uses around sysfs_emit
drivers core: Remove strcat uses around sysfs_emit and neaten
drivers core: Use sysfs_emit and sysfs_emit_at for show(device *...) functions
sysfs: Add sysfs_emit and sysfs_emit_at to format sysfs output
dyndbg: use keyword, arg varnames for query term pairs
driver core: force NOIO allocations during unplug
platform_device: switch to simpler IDA interface
driver core: platform: Document return type of more functions
Revert "driver core: Annotate dev_err_probe() with __must_check"
Revert "test_firmware: Test platform fw loading on non-EFI systems"
iio: adc: xilinx-xadc: use devm_krealloc()
hwmon: pmbus: use more devres helpers
devres: provide devm_krealloc()
syscore: Use pm_pr_dbg() for syscore_{suspend,resume}()
...
Compared to other arch_* functions, arch_set_freq_scale() has an atypical
weak definition that can be replaced by a strong architecture specific
implementation.
The more typical support for architectural functions involves defining
an empty stub in a header file if the symbol is not already defined in
architecture code. Some examples involve:
- #define arch_scale_freq_capacity topology_get_freq_scale
- #define arch_scale_freq_invariant topology_scale_freq_invariant
- #define arch_scale_cpu_capacity topology_get_cpu_scale
- #define arch_update_cpu_topology topology_update_cpu_topology
- #define arch_scale_thermal_pressure topology_get_thermal_pressure
- #define arch_set_thermal_pressure topology_set_thermal_pressure
Bring arch_set_freq_scale() in line with these functions by renaming it to
topology_set_freq_scale() in the arch topology driver, and by defining the
arch_set_freq_scale symbol to point to the new function for arm and arm64.
While there are other users of the arch_topology driver, this patch defines
arch_set_freq_scale for arm and arm64 only, due to their existing
definitions of arch_scale_freq_capacity. This is the getter function of the
frequency invariance scale factor and without a getter function, the
setter function - arch_set_freq_scale() has not purpose.
Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Sudeep Holla <sudeep.holla@arm.com> (BL_SWITCHER and topology parts)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
arch_scale_freq_invariant() is used by schedutil to determine whether
the scheduler's load-tracking signals are frequency invariant. Its
definition is overridable, though by default it is hardcoded to 'true'
if arch_scale_freq_capacity() is defined ('false' otherwise).
This behaviour is not overridden on arm, arm64 and other users of the
generic arch topology driver, which is somewhat precarious:
arch_scale_freq_capacity() will always be defined, yet not all cpufreq
drivers are guaranteed to drive the frequency invariance scale factor
setting. In other words, the load-tracking signals may very well *not*
be frequency invariant.
Now that cpufreq can be queried on whether the current driver is driving
the Frequency Invariance (FI) scale setting, the current situation can
be improved. This combines the query of whether cpufreq supports the
setting of the frequency scale factor, with whether all online CPUs are
counter-based FI enabled.
While cpufreq FI enablement applies at system level, for all CPUs,
counter-based FI support could also be used for only a subset of CPUs to
set the invariance scale factor. Therefore, if cpufreq-based FI support
is present, we consider the system to be invariant. If missing, we
require all online CPUs to be counter-based FI enabled in order for the
full system to be considered invariant.
If the system ends up not being invariant, a new condition is needed in
the counter initialization code that disables all scale factor setting
based on counters.
Precedence of counters over cpufreq use is not important here. The
invariant status is only given to the system if all CPUs have at least
one method of setting the frequency scale factor.
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The passed cpumask arguments to arch_set_freq_scale() and
arch_freq_counters_available() are only iterated over, so reflect this
in the prototype. This also allows to pass system cpumasks like
cpu_online_mask without getting a warning.
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The current frequency passed to arch_set_freq_scale() could end up
being 0, signaling an error in setting a new frequency. Also, if the
maximum frequency in 0, this will result in a division by 0 error.
Therefore, validate these input values before using them for the
setting of the frequency scale factor.
Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
