Commit 31e3adba authored by Jim Harris's avatar Jim Harris Committed by Konrad Sztyber
Browse files

spdk_nvme_perf: use rand_r() twice when choosing random I/O offset 



Fixes issue #3494.

Signed-off-by: default avatarJim Harris <jim.harris@samsung.com>
Change-Id: I5b86c1ab7e532730e365fccb96b5964051f07b76
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/24622


Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: default avatarKonrad Sztyber <konrad.sztyber@intel.com>
Reviewed-by: default avatarShuhei Matsumoto <smatsumoto@nvidia.com>
Community-CI: Mellanox Build Bot
parent 682732fe

app/spdk_nvme_perf/perf.c

+9 −2
Original line number Diff line number Diff line
@@ -1487,7 +1487,7 @@ register_ctrlr(struct spdk_nvme_ctrlr *ctrlr, struct trid_entry *trid_entry) 
static inline void

submit_single_io(struct perf_task *task)

{

	uint64_t		offset_in_ios;

	uint64_t		rand_value, offset_in_ios;

	int			rc;

	struct ns_worker_ctx	*ns_ctx = task->ns_ctx;

	struct ns_entry		*entry = ns_ctx->entry;
@@ -1497,7 +1497,14 @@ submit_single_io(struct perf_task *task) 
	if (entry->zipf) {

		offset_in_ios = spdk_zipf_generate(entry->zipf);

	} else if (g_is_random) {

		offset_in_ios = rand_r(&entry->seed) % entry->size_in_ios;

		/* rand_r() returns int, so we need to use two calls to ensure

		 * we get a large enough value to cover a very large block

		 * device.

		 */

		rand_value = (uint64_t)rand_r(&entry->seed) *

			     ((uint64_t)RAND_MAX + 1) +

			     rand_r(&entry->seed);

		offset_in_ios = rand_value % entry->size_in_ios;

	} else {

		offset_in_ios = ns_ctx->offset_in_ios++;

		if (ns_ctx->offset_in_ios == entry->size_in_ios) {