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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
| commit | 4352b8aee98005853aa63f57d6377282de17a33f (patch) | |
| tree | 27614d7a9ef05c32d089004e104364ce42324837 /lib/cpumask.c | |
| download | linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip | |
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni:
"A new driver this cycle, for the AMD AXI I3C controller.
There are also new features such as IBI wakeup support, SETAASA device
discovery and ACPI support for the the DAA methods, meaning we can now
communicate with the SPD devices on DDR5 modules.
New driver:
- AMD AXI I3C master controller
Subsystem:
- I3C Common Command Code (CCC) handling improvements, especially
around GET CCCs
- SETAASA device discovery support
- ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
well as I2C devices on I3C bus
- IBI-based wakeup support
Drivers:
- dw: SETAASA support
- mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
controller support, PIO queue management support for HCI v1.2
- renesas: improve suspend to RAM support, add runtime PM support"
* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
i3c: dw: reduce do_daa time if there's no client
i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
i3c: dw: rename "pclk" to "apb" to match dt-binding
i3c: dw: make struct dw_i3c_cmd smaller
i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
i3c: renesas: Don't register devices when ENTDAA times out
i3c: master: dw-i3c-master: fix OD timing for first broadcast
i3c: mipi-i3c-hci: Advertise IBI wakeup capability
i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
i3c: master: Reject IBI requests from non-IBI-capable devices
i3c: master: Add helper to query bus wakeup requirements
i3c: master: Report wakeup events for IBIs
i3c: master: Support IBI-based wakeup capability
i3c: master: Fix potential UAF in i3c_device_match()
i3c: master: Fix potential UAF in i3c_device_uevent()
i3c: Make dev->desc locking assumptions explicit
i3c: master: Fix use-after-free of master->this
...
Diffstat (limited to 'lib/cpumask.c')
| -rw-r--r-- | lib/cpumask.c | 168 |
1 files changed, 168 insertions, 0 deletions
diff --git a/lib/cpumask.c b/lib/cpumask.c new file mode 100644 index 000000000..5adb9874f --- /dev/null +++ b/lib/cpumask.c @@ -0,0 +1,168 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/slab.h> +#include <linux/kernel.h> +#include <linux/bitops.h> +#include <linux/cpumask.h> +#include <linux/export.h> +#include <linux/memblock.h> +#include <linux/numa.h> + +/* These are not inline because of header tangles. */ +#ifdef CONFIG_CPUMASK_OFFSTACK +/** + * alloc_cpumask_var_node - allocate a struct cpumask on a given node + * @mask: pointer to cpumask_var_t where the cpumask is returned + * @flags: GFP_ flags + * @node: memory node from which to allocate or %NUMA_NO_NODE + * + * Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is + * a nop returning a constant 1 (in <linux/cpumask.h>). + * + * Return: TRUE if memory allocation succeeded, FALSE otherwise. + * + * In addition, mask will be NULL if this fails. Note that gcc is + * usually smart enough to know that mask can never be NULL if + * CONFIG_CPUMASK_OFFSTACK=n, so does code elimination in that case + * too. + */ +bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node) +{ + *mask = kmalloc_node(cpumask_size(), flags, node); + +#ifdef CONFIG_DEBUG_PER_CPU_MAPS + if (!*mask) { + printk(KERN_ERR "=> alloc_cpumask_var: failed!\n"); + dump_stack(); + } +#endif + + return *mask != NULL; +} +EXPORT_SYMBOL(alloc_cpumask_var_node); + +/** + * alloc_bootmem_cpumask_var - allocate a struct cpumask from the bootmem arena. + * @mask: pointer to cpumask_var_t where the cpumask is returned + * + * Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is + * a nop (in <linux/cpumask.h>). + * Either returns an allocated (zero-filled) cpumask, or causes the + * system to panic. + */ +void __init alloc_bootmem_cpumask_var(cpumask_var_t *mask) +{ + *mask = memblock_alloc_or_panic(cpumask_size(), SMP_CACHE_BYTES); +} + +/** + * free_cpumask_var - frees memory allocated for a struct cpumask. + * @mask: cpumask to free + * + * This is safe on a NULL mask. + */ +void free_cpumask_var(cpumask_var_t mask) +{ + kfree(mask); +} +EXPORT_SYMBOL(free_cpumask_var); + +/** + * free_bootmem_cpumask_var - frees result of alloc_bootmem_cpumask_var + * @mask: cpumask to free + */ +void __init free_bootmem_cpumask_var(cpumask_var_t mask) +{ + memblock_free(mask, cpumask_size()); +} +#endif + +/** + * cpumask_local_spread - select the i'th cpu based on NUMA distances + * @i: index number + * @node: local numa_node + * + * Return: online CPU according to a numa aware policy; local cpus are returned + * first, followed by non-local ones, then it wraps around. + * + * For those who wants to enumerate all CPUs based on their NUMA distances, + * i.e. call this function in a loop, like: + * + * for (i = 0; i < num_online_cpus(); i++) { + * cpu = cpumask_local_spread(i, node); + * do_something(cpu); + * } + * + * There's a better alternative based on for_each()-like iterators: + * + * for_each_numa_hop_mask(mask, node) { + * for_each_cpu_andnot(cpu, mask, prev) + * do_something(cpu); + * prev = mask; + * } + * + * It's simpler and more verbose than above. Complexity of iterator-based + * enumeration is O(sched_domains_numa_levels * nr_cpu_ids), while + * cpumask_local_spread() when called for each cpu is + * O(sched_domains_numa_levels * nr_cpu_ids * log(nr_cpu_ids)). + */ +unsigned int cpumask_local_spread(unsigned int i, int node) +{ + unsigned int cpu; + + /* Wrap: we always want a cpu. */ + i %= num_online_cpus(); + + cpu = sched_numa_find_nth_cpu(cpu_online_mask, i, node); + + WARN_ON(cpu >= nr_cpu_ids); + return cpu; +} +EXPORT_SYMBOL(cpumask_local_spread); + +static DEFINE_PER_CPU(int, distribute_cpu_mask_prev); + +/** + * cpumask_any_and_distribute - Return an arbitrary cpu within src1p & src2p. + * @src1p: first &cpumask for intersection + * @src2p: second &cpumask for intersection + * + * Iterated calls using the same srcp1 and srcp2 will be distributed within + * their intersection. + * + * Return: >= nr_cpu_ids if the intersection is empty. + */ +unsigned int cpumask_any_and_distribute(const struct cpumask *src1p, + const struct cpumask *src2p) +{ + unsigned int next, prev; + + /* NOTE: our first selection will skip 0. */ + prev = __this_cpu_read(distribute_cpu_mask_prev); + + next = cpumask_next_and_wrap(prev, src1p, src2p); + if (next < nr_cpu_ids) + __this_cpu_write(distribute_cpu_mask_prev, next); + + return next; +} +EXPORT_SYMBOL(cpumask_any_and_distribute); + +/** + * cpumask_any_distribute - Return an arbitrary cpu from srcp + * @srcp: &cpumask for selection + * + * Return: >= nr_cpu_ids if the intersection is empty. + */ +unsigned int cpumask_any_distribute(const struct cpumask *srcp) +{ + unsigned int next, prev; + + /* NOTE: our first selection will skip 0. */ + prev = __this_cpu_read(distribute_cpu_mask_prev); + next = cpumask_next_wrap(prev, srcp); + if (next < nr_cpu_ids) + __this_cpu_write(distribute_cpu_mask_prev, next); + + return next; +} +EXPORT_SYMBOL(cpumask_any_distribute); |
