diff options
| -rw-r--r-- | drivers/nvdimm/nd.h | 1 | ||||
| -rw-r--r-- | drivers/nvdimm/region_devs.c | 17 |
2 files changed, 15 insertions, 3 deletions
diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h index 5912bd6b4234..40476399d227 100644 --- a/drivers/nvdimm/nd.h +++ b/drivers/nvdimm/nd.h @@ -52,6 +52,7 @@ struct nvdimm_drvdata { struct nd_region_data { int ns_count; int ns_active; + unsigned int flush_mask; void __iomem *flush_wpq[0][0]; }; diff --git a/drivers/nvdimm/region_devs.c b/drivers/nvdimm/region_devs.c index 5d97b127b715..e8d5ba7b29af 100644 --- a/drivers/nvdimm/region_devs.c +++ b/drivers/nvdimm/region_devs.c @@ -14,6 +14,7 @@ #include <linux/highmem.h> #include <linux/sched.h> #include <linux/slab.h> +#include <linux/hash.h> #include <linux/pmem.h> #include <linux/sort.h> #include <linux/io.h> @@ -28,6 +29,7 @@ #include <linux/io-64-nonatomic-hi-lo.h> static DEFINE_IDA(region_ida); +static DEFINE_PER_CPU(int, flush_idx); static int nvdimm_map_flush(struct device *dev, struct nvdimm *nvdimm, int dimm, struct nd_region_data *ndrd) @@ -67,7 +69,7 @@ static int nvdimm_map_flush(struct device *dev, struct nvdimm *nvdimm, int dimm, int nd_region_activate(struct nd_region *nd_region) { - int i; + int i, num_flush = 0; struct nd_region_data *ndrd; struct device *dev = &nd_region->dev; size_t flush_data_size = sizeof(void *); @@ -79,6 +81,7 @@ int nd_region_activate(struct nd_region *nd_region) /* at least one null hint slot per-dimm for the "no-hint" case */ flush_data_size += sizeof(void *); + num_flush = min_not_zero(num_flush, nvdimm->num_flush); if (!nvdimm->num_flush) continue; flush_data_size += nvdimm->num_flush * sizeof(void *); @@ -90,6 +93,7 @@ int nd_region_activate(struct nd_region *nd_region) return -ENOMEM; dev_set_drvdata(dev, ndrd); + ndrd->flush_mask = (1 << ilog2(num_flush)) - 1; for (i = 0; i < nd_region->ndr_mappings; i++) { struct nd_mapping *nd_mapping = &nd_region->mapping[i]; struct nvdimm *nvdimm = nd_mapping->nvdimm; @@ -878,7 +882,14 @@ EXPORT_SYMBOL_GPL(nvdimm_volatile_region_create); void nvdimm_flush(struct nd_region *nd_region) { struct nd_region_data *ndrd = dev_get_drvdata(&nd_region->dev); - int i; + int i, idx; + + /* + * Try to encourage some diversity in flush hint addresses + * across cpus assuming a limited number of flush hints. + */ + idx = this_cpu_read(flush_idx); + idx = this_cpu_add_return(flush_idx, hash_32(current->pid + idx, 8)); /* * The first wmb() is needed to 'sfence' all previous writes @@ -890,7 +901,7 @@ void nvdimm_flush(struct nd_region *nd_region) wmb(); for (i = 0; i < nd_region->ndr_mappings; i++) if (ndrd->flush_wpq[i][0]) - writeq(1, ndrd->flush_wpq[i][0]); + writeq(1, ndrd->flush_wpq[i][idx & ndrd->flush_mask]); wmb(); } EXPORT_SYMBOL_GPL(nvdimm_flush); |