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authorLinus Torvalds <torvalds@linux-foundation.org>2025-12-05 21:29:02 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2025-12-05 21:29:02 -0800
commit416f99c3b16f582a3fc6d64a1f77f39d94b76de5 (patch)
tree8322813d7c49c3a99550eaf80c245bc163685b83 /drivers/base/arch_topology.c
parentb1ae17cd0f0a2ffe1e9da007587c8eebb1bf8c69 (diff)
parent473b9f331718267815649cd93801da832200db71 (diff)
Merge tag 'driver-core-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-coreHEADmainline
Pull driver core updates from Danilo Krummrich: "Arch Topology: - Move parse_acpi_topology() from arm64 to common code for reuse in RISC-V CPU: - Expose housekeeping CPUs through /sys/devices/system/cpu/housekeeping - Print a newline (or 0x0A) instead of '(null)' reading /sys/devices/system/cpu/nohz_full when nohz_full= is not set debugfs - Remove (broken) 'no-mount' mode - Remove redundant access mode checks in debugfs_get_tree() and debugfs_create_*() functions Devres: - Remove unused devm_free_percpu() helper - Move devm_alloc_percpu() from device.h to devres.h Firmware Loader: - Replace simple_strtol() with kstrtoint() - Do not call cancel_store() when no upload is in progress kernfs: - Increase struct super_block::maxbytes to MAX_LFS_FILESIZE - Fix a missing unwind path in __kernfs_new_node() Misc: - Increase the name size in struct auxiliary_device_id to 40 characters - Replace system_unbound_wq with system_dfl_wq and add WQ_PERCPU to alloc_workqueue() Platform: - Replace ERR_PTR() with IOMEM_ERR_PTR() in platform ioremap functions Rust: - Auxiliary: - Unregister auxiliary device on parent device unbind - Move parent() to impl Device; implement device context aware parent() for Device<Bound> - Illustrate how to safely obtain a driver's device private data when calling from an auxiliary driver into the parant device driver - DebugFs: - Implement support for binary large objects - Device: - Let probe() return the driver's device private data as pinned initializer, i.e. impl PinInit<Self, Error> - Implement safe accessor for a driver's device private data for Device<Bound> (returned reference can't out-live driver binding and guarantees the correct private data type) - Implement AsBusDevice trait, to be used by class device abstractions to derive the bus device type of the parent device - DMA: - Store raw pointer of allocation as NonNull - Use start_ptr() and start_ptr_mut() to inherit correct mutability of self - FS: - Add file::Offset type alias - I2C: - Add abstractions for I2C device / driver infrastructure - Implement abstractions for manual I2C device registrations - I/O: - Use "kernel vertical" style for imports - Define ResourceSize as resource_size_t - Move ResourceSize to top-level I/O module - Add type alias for phys_addr_t - Implement Rust version of read_poll_timeout_atomic() - PCI: - Use "kernel vertical" style for imports - Move I/O and IRQ infrastructure to separate files - Add support for PCI interrupt vectors - Implement TryInto<IrqRequest<'a>> for IrqVector<'a> to convert an IrqVector bound to specific pci::Device into an IrqRequest bound to the same pci::Device's parent Device - Leverage pin_init_scope() to get rid of redundant Result in IRQ methods - PinInit: - Add {pin_}init_scope() to execute code before creating an initializer - Platform: - Leverage pin_init_scope() to get rid of redundant Result in IRQ methods - Timekeeping: - Implement abstraction of udelay() - Uaccess: - Implement read_slice_partial() and read_slice_file() for UserSliceReader - Implement write_slice_partial() and write_slice_file() for UserSliceWriter sysfs: - Prepare the constification of struct attribute" * tag 'driver-core-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: (75 commits) rust: pci: fix build failure when CONFIG_PCI_MSI is disabled debugfs: Fix default access mode config check debugfs: Remove broken no-mount mode debugfs: Remove redundant access mode checks driver core: Check drivers_autoprobe for all added devices driver core: WQ_PERCPU added to alloc_workqueue users driver core: replace use of system_unbound_wq with system_dfl_wq tick/nohz: Expose housekeeping CPUs in sysfs tick/nohz: avoid showing '(null)' if nohz_full= not set sysfs/cpu: Use DEVICE_ATTR_RO for nohz_full attribute kernfs: fix memory leak of kernfs_iattrs in __kernfs_new_node fs/kernfs: raise sb->maxbytes to MAX_LFS_FILESIZE mod_devicetable: Bump auxiliary_device_id name size sysfs: simplify attribute definition macros samples/kobject: constify 'struct foo_attribute' samples/kobject: add is_visible() callback to attribute group sysfs: attribute_group: enable const variants of is_visible() sysfs: introduce __SYSFS_FUNCTION_ALTERNATIVE() sysfs: transparently handle const pointers in ATTRIBUTE_GROUPS() sysfs: attribute_group: allow registration of const attribute ...
Diffstat (limited to 'drivers/base/arch_topology.c')
-rw-r--r--drivers/base/arch_topology.c96
1 files changed, 95 insertions, 1 deletions
diff --git a/drivers/base/arch_topology.c b/drivers/base/arch_topology.c
index e1eff05bea4a..84ec92bff642 100644
--- a/drivers/base/arch_topology.c
+++ b/drivers/base/arch_topology.c
@@ -823,12 +823,106 @@ void remove_cpu_topology(unsigned int cpu)
clear_cpu_topology(cpu);
}
+#if defined(CONFIG_ARM64) || defined(CONFIG_RISCV)
+struct cpu_smt_info {
+ unsigned int thread_num;
+ int core_id;
+};
+
+static bool __init acpi_cpu_is_threaded(int cpu)
+{
+ int is_threaded = acpi_pptt_cpu_is_thread(cpu);
+
+ /*
+ * if the PPTT doesn't have thread information, check for architecture
+ * specific fallback if available
+ */
+ if (is_threaded < 0)
+ is_threaded = arch_cpu_is_threaded();
+
+ return !!is_threaded;
+}
+
+/*
+ * Propagate the topology information of the processor_topology_node tree to the
+ * cpu_topology array.
+ */
__weak int __init parse_acpi_topology(void)
{
+ unsigned int max_smt_thread_num = 1;
+ struct cpu_smt_info *entry;
+ struct xarray hetero_cpu;
+ unsigned long hetero_id;
+ int cpu, topology_id;
+
+ if (acpi_disabled)
+ return 0;
+
+ xa_init(&hetero_cpu);
+
+ for_each_possible_cpu(cpu) {
+ topology_id = find_acpi_cpu_topology(cpu, 0);
+ if (topology_id < 0)
+ return topology_id;
+
+ if (acpi_cpu_is_threaded(cpu)) {
+ cpu_topology[cpu].thread_id = topology_id;
+ topology_id = find_acpi_cpu_topology(cpu, 1);
+ cpu_topology[cpu].core_id = topology_id;
+
+ /*
+ * In the PPTT, CPUs below a node with the 'identical
+ * implementation' flag have the same number of threads.
+ * Count the number of threads for only one CPU (i.e.
+ * one core_id) among those with the same hetero_id.
+ * See the comment of find_acpi_cpu_topology_hetero_id()
+ * for more details.
+ *
+ * One entry is created for each node having:
+ * - the 'identical implementation' flag
+ * - its parent not having the flag
+ */
+ hetero_id = find_acpi_cpu_topology_hetero_id(cpu);
+ entry = xa_load(&hetero_cpu, hetero_id);
+ if (!entry) {
+ entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+ WARN_ON_ONCE(!entry);
+
+ if (entry) {
+ entry->core_id = topology_id;
+ entry->thread_num = 1;
+ xa_store(&hetero_cpu, hetero_id,
+ entry, GFP_KERNEL);
+ }
+ } else if (entry->core_id == topology_id) {
+ entry->thread_num++;
+ }
+ } else {
+ cpu_topology[cpu].thread_id = -1;
+ cpu_topology[cpu].core_id = topology_id;
+ }
+ topology_id = find_acpi_cpu_topology_cluster(cpu);
+ cpu_topology[cpu].cluster_id = topology_id;
+ topology_id = find_acpi_cpu_topology_package(cpu);
+ cpu_topology[cpu].package_id = topology_id;
+ }
+
+ /*
+ * This is a short loop since the number of XArray elements is the
+ * number of heterogeneous CPU clusters. On a homogeneous system
+ * there's only one entry in the XArray.
+ */
+ xa_for_each(&hetero_cpu, hetero_id, entry) {
+ max_smt_thread_num = max(max_smt_thread_num, entry->thread_num);
+ xa_erase(&hetero_cpu, hetero_id);
+ kfree(entry);
+ }
+
+ cpu_smt_set_num_threads(max_smt_thread_num, max_smt_thread_num);
+ xa_destroy(&hetero_cpu);
return 0;
}
-#if defined(CONFIG_ARM64) || defined(CONFIG_RISCV)
void __init init_cpu_topology(void)
{
int cpu, ret;