/* * linux/mm/allocpercpu.c * * Separated from slab.c August 11, 2006 Christoph Lameter <clameter@sgi.com> */ #include <linux/mm.h> #include <linux/module.h> /** * percpu_depopulate - depopulate per-cpu data for given cpu * @__pdata: per-cpu data to depopulate * @cpu: depopulate per-cpu data for this cpu * * Depopulating per-cpu data for a cpu going offline would be a typical * use case. You need to register a cpu hotplug handler for that purpose. */ void percpu_depopulate(void *__pdata, int cpu) { struct percpu_data *pdata = __percpu_disguise(__pdata); kfree(pdata->ptrs[cpu]); pdata->ptrs[cpu] = NULL; } EXPORT_SYMBOL_GPL(percpu_depopulate); /** * percpu_depopulate_mask - depopulate per-cpu data for some cpu's * @__pdata: per-cpu data to depopulate * @mask: depopulate per-cpu data for cpu's selected through mask bits */ void __percpu_depopulate_mask(void *__pdata, cpumask_t *mask) { int cpu; for_each_cpu_mask(cpu, *mask) percpu_depopulate(__pdata, cpu); } EXPORT_SYMBOL_GPL(__percpu_depopulate_mask); /** * percpu_populate - populate per-cpu data for given cpu * @__pdata: per-cpu data to populate further * @size: size of per-cpu object * @gfp: may sleep or not etc. * @cpu: populate per-data for this cpu * * Populating per-cpu data for a cpu coming online would be a typical * use case. You need to register a cpu hotplug handler for that purpose. * Per-cpu object is populated with zeroed buffer. */ void *percpu_populate(void *__pdata, size_t size, gfp_t gfp, int cpu) { struct percpu_data *pdata = __percpu_disguise(__pdata); int node = cpu_to_node(cpu); BUG_ON(pdata->ptrs[cpu]); if (node_online(node)) pdata->ptrs[cpu] = kmalloc_node(size, gfp|__GFP_ZERO, node); else pdata->ptrs[cpu] = kzalloc(size, gfp); return pdata->ptrs[cpu]; } EXPORT_SYMBOL_GPL(percpu_populate); /** * percpu_populate_mask - populate per-cpu data for more cpu's * @__pdata: per-cpu data to populate further * @size: size of per-cpu object * @gfp: may sleep or not etc. * @mask: populate per-cpu data for cpu's selected through mask bits * * Per-cpu objects are populated with zeroed buffers. */ int __percpu_populate_mask(void *__pdata, size_t size, gfp_t gfp, cpumask_t *mask) { cpumask_t populated = CPU_MASK_NONE; int cpu; for_each_cpu_mask(cpu, *mask) if (unlikely(!percpu_populate(__pdata, size, gfp, cpu))) { __percpu_depopulate_mask(__pdata, &populated); return -ENOMEM; } else cpu_set(cpu, populated); return 0; } EXPORT_SYMBOL_GPL(__percpu_populate_mask); /** * percpu_alloc_mask - initial setup of per-cpu data * @size: size of per-cpu object * @gfp: may sleep or not etc. * @mask: populate per-data for cpu's selected through mask bits * * Populating per-cpu data for all online cpu's would be a typical use case, * which is simplified by the percpu_alloc() wrapper. * Per-cpu objects are populated with zeroed buffers. */ void *__percpu_alloc_mask(size_t size, gfp_t gfp, cpumask_t *mask) { void *pdata = kzalloc(nr_cpu_ids * sizeof(void *), gfp); void *__pdata = __percpu_disguise(pdata); if (unlikely(!pdata)) return NULL; if (likely(!__percpu_populate_mask(__pdata, size, gfp, mask))) return __pdata; kfree(pdata); return NULL; } EXPORT_SYMBOL_GPL(__percpu_alloc_mask); /** * percpu_free - final cleanup of per-cpu data * @__pdata: object to clean up * * We simply clean up any per-cpu object left. No need for the client to * track and specify through a bis mask which per-cpu objects are to free. */ void percpu_free(void *__pdata) { if (unlikely(!__pdata)) return; __percpu_depopulate_mask(__pdata, &cpu_possible_map); kfree(__percpu_disguise(__pdata)); } EXPORT_SYMBOL_GPL(percpu_free);