path: root/include/linux/irq.h
diff options
authorThomas Gleixner <tglx@linutronix.de>2017-09-13 23:29:14 +0200
committerThomas Gleixner <tglx@linutronix.de>2017-09-25 20:38:26 +0200
commit2f75d9e1c90511bff6d1ce4de94503cc28fec032 (patch)
treeeb17ed8cb0cbd6c10cc3119267e790d8a4a1bb8c /include/linux/irq.h
parent22d0b12f3560d3b3264ee79faa1c05a5060fb916 (diff)
genirq: Implement bitmap matrix allocator
Implement the infrastructure for a simple bitmap based allocator, which will replace the x86 vector allocator. It's in the core code as other architectures might be able to reuse/extend it. For now it only implements allocations for single CPUs, but it's simple to add multi CPU allocation support if required. The concept is rather simple: Global information: system_vector bitmap global accounting PerCPU information: allocation bitmap managed allocation bitmap local accounting The system vector bitmap is used to exclude vectors system wide from the allocation space. The allocation bitmap is used to keep track of per cpu used vectors. The managed allocation bitmap is used to reserve vectors for managed interrupts. When a regular (non managed) interrupt allocation happens then the following rule applies: tmpmap = system_map | alloc_map | managed_map find_zero_bit(tmpmap) Oring the bitmaps together gives the real available space. The same rule applies for reserving a managed interrupt vector. But contrary to the regular interrupts the reservation only marks the bit in the managed map and therefor excludes it from the regular allocations. The managed map is only cleaned out when the a managed interrupt is completely released and it stays alive accross CPU offline/online operations. For managed interrupt allocations the rule is: tmpmap = managed_map & ~alloc_map find_first_bit(tmpmap) This returns the first bit which is in the managed map, but not yet allocated in the allocation map. The allocation marks it in the allocation map and hands it back to the caller for use. The rest of the code are helper functions to handle the various requirements and the accounting which are necessary to replace the x86 vector allocation code. The result is a single patch as the evolution of this infrastructure cannot be represented in bits and pieces. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Tested-by: Yu Chen <yu.c.chen@intel.com> Acked-by: Juergen Gross <jgross@suse.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Alok Kataria <akataria@vmware.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Rui Zhang <rui.zhang@intel.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: Len Brown <lenb@kernel.org> Link: https://lkml.kernel.org/r/20170913213153.185437174@linutronix.de
Diffstat (limited to 'include/linux/irq.h')
1 files changed, 22 insertions, 0 deletions
diff --git a/include/linux/irq.h b/include/linux/irq.h
index d4728bf6a537..fda8da7c45e7 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -1113,6 +1113,28 @@ static inline u32 irq_reg_readl(struct irq_chip_generic *gc,
return readl(gc->reg_base + reg_offset);
+struct irq_matrix;
+struct irq_matrix *irq_alloc_matrix(unsigned int matrix_bits,
+ unsigned int alloc_start,
+ unsigned int alloc_end);
+void irq_matrix_online(struct irq_matrix *m);
+void irq_matrix_offline(struct irq_matrix *m);
+void irq_matrix_assign_system(struct irq_matrix *m, unsigned int bit, bool replace);
+int irq_matrix_reserve_managed(struct irq_matrix *m, const struct cpumask *msk);
+void irq_matrix_remove_managed(struct irq_matrix *m, const struct cpumask *msk);
+int irq_matrix_alloc_managed(struct irq_matrix *m, unsigned int cpu);
+void irq_matrix_reserve(struct irq_matrix *m);
+void irq_matrix_remove_reserved(struct irq_matrix *m);
+int irq_matrix_alloc(struct irq_matrix *m, const struct cpumask *msk,
+ bool reserved, unsigned int *mapped_cpu);
+void irq_matrix_free(struct irq_matrix *m, unsigned int cpu,
+ unsigned int bit, bool managed);
+void irq_matrix_assign(struct irq_matrix *m, unsigned int bit);
+unsigned int irq_matrix_available(struct irq_matrix *m, bool cpudown);
+unsigned int irq_matrix_allocated(struct irq_matrix *m);
+unsigned int irq_matrix_reserved(struct irq_matrix *m);
+void irq_matrix_debug_show(struct seq_file *sf, struct irq_matrix *m, int ind);
/* Contrary to Linux irqs, for hardware irqs the irq number 0 is valid */
#define INVALID_HWIRQ (~0UL)
irq_hw_number_t ipi_get_hwirq(unsigned int irq, unsigned int cpu);