// SPDX-License-Identifier: GPL-2.0 // Copyright (C) 2017 Thomas Gleixner <[email protected]> #include <linux/spinlock.h> #include <linux/seq_file.h> #include <linux/bitmap.h> #include <linux/percpu.h> #include <linux/cpu.h> #include <linux/irq.h> struct cpumap { … }; struct irq_matrix { … }; #define CREATE_TRACE_POINTS #include <trace/events/irq_matrix.h> /** * irq_alloc_matrix - Allocate a irq_matrix structure and initialize it * @matrix_bits: Number of matrix bits must be <= IRQ_MATRIX_BITS * @alloc_start: From which bit the allocation search starts * @alloc_end: At which bit the allocation search ends, i.e first * invalid bit */ __init struct irq_matrix *irq_alloc_matrix(unsigned int matrix_bits, unsigned int alloc_start, unsigned int alloc_end) { … } /** * irq_matrix_online - Bring the local CPU matrix online * @m: Matrix pointer */ void irq_matrix_online(struct irq_matrix *m) { … } /** * irq_matrix_offline - Bring the local CPU matrix offline * @m: Matrix pointer */ void irq_matrix_offline(struct irq_matrix *m) { … } static unsigned int matrix_alloc_area(struct irq_matrix *m, struct cpumap *cm, unsigned int num, bool managed) { … } /* Find the best CPU which has the lowest vector allocation count */ static unsigned int matrix_find_best_cpu(struct irq_matrix *m, const struct cpumask *msk) { … } /* Find the best CPU which has the lowest number of managed IRQs allocated */ static unsigned int matrix_find_best_cpu_managed(struct irq_matrix *m, const struct cpumask *msk) { … } /** * irq_matrix_assign_system - Assign system wide entry in the matrix * @m: Matrix pointer * @bit: Which bit to reserve * @replace: Replace an already allocated vector with a system * vector at the same bit position. * * The BUG_ON()s below are on purpose. If this goes wrong in the * early boot process, then the chance to survive is about zero. * If this happens when the system is life, it's not much better. */ void irq_matrix_assign_system(struct irq_matrix *m, unsigned int bit, bool replace) { … } /** * irq_matrix_reserve_managed - Reserve a managed interrupt in a CPU map * @m: Matrix pointer * @msk: On which CPUs the bits should be reserved. * * Can be called for offline CPUs. Note, this will only reserve one bit * on all CPUs in @msk, but it's not guaranteed that the bits are at the * same offset on all CPUs */ int irq_matrix_reserve_managed(struct irq_matrix *m, const struct cpumask *msk) { … } /** * irq_matrix_remove_managed - Remove managed interrupts in a CPU map * @m: Matrix pointer * @msk: On which CPUs the bits should be removed * * Can be called for offline CPUs * * This removes not allocated managed interrupts from the map. It does * not matter which one because the managed interrupts free their * allocation when they shut down. If not, the accounting is screwed, * but all what can be done at this point is warn about it. */ void irq_matrix_remove_managed(struct irq_matrix *m, const struct cpumask *msk) { … } /** * irq_matrix_alloc_managed - Allocate a managed interrupt in a CPU map * @m: Matrix pointer * @msk: Which CPUs to search in * @mapped_cpu: Pointer to store the CPU for which the irq was allocated */ int irq_matrix_alloc_managed(struct irq_matrix *m, const struct cpumask *msk, unsigned int *mapped_cpu) { … } /** * irq_matrix_assign - Assign a preallocated interrupt in the local CPU map * @m: Matrix pointer * @bit: Which bit to mark * * This should only be used to mark preallocated vectors */ void irq_matrix_assign(struct irq_matrix *m, unsigned int bit) { … } /** * irq_matrix_reserve - Reserve interrupts * @m: Matrix pointer * * This is merely a book keeping call. It increments the number of globally * reserved interrupt bits w/o actually allocating them. This allows to * setup interrupt descriptors w/o assigning low level resources to it. * The actual allocation happens when the interrupt gets activated. */ void irq_matrix_reserve(struct irq_matrix *m) { … } /** * irq_matrix_remove_reserved - Remove interrupt reservation * @m: Matrix pointer * * This is merely a book keeping call. It decrements the number of globally * reserved interrupt bits. This is used to undo irq_matrix_reserve() when the * interrupt was never in use and a real vector allocated, which undid the * reservation. */ void irq_matrix_remove_reserved(struct irq_matrix *m) { … } /** * irq_matrix_alloc - Allocate a regular interrupt in a CPU map * @m: Matrix pointer * @msk: Which CPUs to search in * @reserved: Allocate previously reserved interrupts * @mapped_cpu: Pointer to store the CPU for which the irq was allocated */ int irq_matrix_alloc(struct irq_matrix *m, const struct cpumask *msk, bool reserved, unsigned int *mapped_cpu) { … } /** * irq_matrix_free - Free allocated interrupt in the matrix * @m: Matrix pointer * @cpu: Which CPU map needs be updated * @bit: The bit to remove * @managed: If true, the interrupt is managed and not accounted * as available. */ void irq_matrix_free(struct irq_matrix *m, unsigned int cpu, unsigned int bit, bool managed) { … } /** * irq_matrix_available - Get the number of globally available irqs * @m: Pointer to the matrix to query * @cpudown: If true, the local CPU is about to go down, adjust * the number of available irqs accordingly */ unsigned int irq_matrix_available(struct irq_matrix *m, bool cpudown) { … } /** * irq_matrix_reserved - Get the number of globally reserved irqs * @m: Pointer to the matrix to query */ unsigned int irq_matrix_reserved(struct irq_matrix *m) { … } /** * irq_matrix_allocated - Get the number of allocated non-managed irqs on the local CPU * @m: Pointer to the matrix to search * * This returns number of allocated non-managed interrupts. */ unsigned int irq_matrix_allocated(struct irq_matrix *m) { … } #ifdef CONFIG_GENERIC_IRQ_DEBUGFS /** * irq_matrix_debug_show - Show detailed allocation information * @sf: Pointer to the seq_file to print to * @m: Pointer to the matrix allocator * @ind: Indentation for the print format * * Note, this is a lockless snapshot. */ void irq_matrix_debug_show(struct seq_file *sf, struct irq_matrix *m, int ind) { … } #endif