X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=mm%2Fallocpercpu.c;h=df34ceae0c678569446930eaf5ceb982a496f8b9;hb=89ccf465abe6b20d804a63ae20307970c441369d;hp=b2486cf887a06c1ecbd3c3d60d10682e2e5fc7d0;hpb=a120586873d3d64de93bd6d593d237e131994e58;p=safe%2Fjmp%2Flinux-2.6 diff --git a/mm/allocpercpu.c b/mm/allocpercpu.c index b2486cf..df34cea 100644 --- a/mm/allocpercpu.c +++ b/mm/allocpercpu.c @@ -1,10 +1,16 @@ /* * linux/mm/allocpercpu.c * - * Separated from slab.c August 11, 2006 Christoph Lameter + * Separated from slab.c August 11, 2006 Christoph Lameter */ #include #include +#include +#include + +#ifndef cache_line_size +#define cache_line_size() L1_CACHE_BYTES +#endif /** * percpu_depopulate - depopulate per-cpu data for given cpu @@ -14,27 +20,28 @@ * 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) +static 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) +static void __percpu_depopulate_mask(void *__pdata, const cpumask_t *mask) { int cpu; - for_each_cpu_mask(cpu, *mask) + for_each_cpu_mask_nr(cpu, *mask) percpu_depopulate(__pdata, cpu); } -EXPORT_SYMBOL_GPL(__percpu_depopulate_mask); + +#define percpu_depopulate_mask(__pdata, mask) \ + __percpu_depopulate_mask((__pdata), &(mask)) /** * percpu_populate - populate per-cpu data for given cpu @@ -47,22 +54,23 @@ EXPORT_SYMBOL_GPL(__percpu_depopulate_mask); * 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) +static 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); + /* + * We should make sure each CPU gets private memory. + */ + size = roundup(size, cache_line_size()); + BUG_ON(pdata->ptrs[cpu]); - if (node_online(node)) { - /* FIXME: kzalloc_node(size, gfp, node) */ - pdata->ptrs[cpu] = kmalloc_node(size, gfp, node); - if (pdata->ptrs[cpu]) - memset(pdata->ptrs[cpu], 0, size); - } else + 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 @@ -73,13 +81,14 @@ EXPORT_SYMBOL_GPL(percpu_populate); * * Per-cpu objects are populated with zeroed buffers. */ -int __percpu_populate_mask(void *__pdata, size_t size, gfp_t gfp, - cpumask_t *mask) +static int __percpu_populate_mask(void *__pdata, size_t size, gfp_t gfp, + cpumask_t *mask) { - cpumask_t populated = CPU_MASK_NONE; + cpumask_t populated; int cpu; - for_each_cpu_mask(cpu, *mask) + cpus_clear(populated); + for_each_cpu_mask_nr(cpu, *mask) if (unlikely(!percpu_populate(__pdata, size, gfp, cpu))) { __percpu_depopulate_mask(__pdata, &populated); return -ENOMEM; @@ -87,44 +96,82 @@ int __percpu_populate_mask(void *__pdata, size_t size, gfp_t gfp, cpu_set(cpu, populated); return 0; } -EXPORT_SYMBOL_GPL(__percpu_populate_mask); + +#define percpu_populate_mask(__pdata, size, gfp, mask) \ + __percpu_populate_mask((__pdata), (size), (gfp), &(mask)) /** - * percpu_alloc_mask - initial setup of per-cpu data + * alloc_percpu - 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 + * @align: alignment * - * 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. + * Allocate dynamic percpu area. Percpu objects are populated with + * zeroed buffers. */ -void *__percpu_alloc_mask(size_t size, gfp_t gfp, cpumask_t *mask) +void *__alloc_percpu(size_t size, size_t align) { - void *pdata = kzalloc(sizeof(struct percpu_data), gfp); + /* + * We allocate whole cache lines to avoid false sharing + */ + size_t sz = roundup(nr_cpu_ids * sizeof(void *), cache_line_size()); + void *pdata = kzalloc(sz, GFP_KERNEL); void *__pdata = __percpu_disguise(pdata); + /* + * Can't easily make larger alignment work with kmalloc. WARN + * on it. Larger alignment should only be used for module + * percpu sections on SMP for which this path isn't used. + */ + WARN_ON_ONCE(align > SMP_CACHE_BYTES); + if (unlikely(!pdata)) return NULL; - if (likely(!__percpu_populate_mask(__pdata, size, gfp, mask))) + if (likely(!__percpu_populate_mask(__pdata, size, GFP_KERNEL, + &cpu_possible_map))) return __pdata; kfree(pdata); return NULL; } -EXPORT_SYMBOL_GPL(__percpu_alloc_mask); +EXPORT_SYMBOL_GPL(__alloc_percpu); /** - * percpu_free - final cleanup of per-cpu data + * free_percpu - 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) +void free_percpu(void *__pdata) { if (unlikely(!__pdata)) return; - __percpu_depopulate_mask(__pdata, &cpu_possible_map); + __percpu_depopulate_mask(__pdata, cpu_possible_mask); kfree(__percpu_disguise(__pdata)); } -EXPORT_SYMBOL_GPL(percpu_free); +EXPORT_SYMBOL_GPL(free_percpu); + +/* + * Generic percpu area setup. + */ +#ifndef CONFIG_HAVE_SETUP_PER_CPU_AREA +unsigned long __per_cpu_offset[NR_CPUS] __read_mostly; + +EXPORT_SYMBOL(__per_cpu_offset); + +void __init setup_per_cpu_areas(void) +{ + unsigned long size, i; + char *ptr; + unsigned long nr_possible_cpus = num_possible_cpus(); + + /* Copy section for each CPU (we discard the original) */ + size = ALIGN(PERCPU_ENOUGH_ROOM, PAGE_SIZE); + ptr = alloc_bootmem_pages(size * nr_possible_cpus); + + for_each_possible_cpu(i) { + __per_cpu_offset[i] = ptr - __per_cpu_start; + memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start); + ptr += size; + } +} +#endif /* CONFIG_HAVE_SETUP_PER_CPU_AREA */