[PATCH v4] nvme-pci: add module parameter for io queue depth
weiping zhang
zhangweiping at didichuxing.com
Mon Jul 10 01:46:59 PDT 2017
Adjust io queue depth more easily, and make sure io queue depth >= 2.
Signed-off-by: weiping zhang <zhangweiping at didichuxing.com>
---
drivers/nvme/host/pci.c | 25 ++++++++++++++++++++++---
1 file changed, 22 insertions(+), 3 deletions(-)
diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 73fddf2..8470503 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -35,7 +35,6 @@
#include "nvme.h"
-#define NVME_Q_DEPTH 1024
#define SQ_SIZE(depth) (depth * sizeof(struct nvme_command))
#define CQ_SIZE(depth) (depth * sizeof(struct nvme_completion))
@@ -57,6 +56,16 @@ module_param(max_host_mem_size_mb, uint, 0444);
MODULE_PARM_DESC(max_host_mem_size_mb,
"Maximum Host Memory Buffer (HMB) size per controller (in MiB)");
+static int io_queue_depth_set(const char *val, const struct kernel_param *kp);
+static const struct kernel_param_ops io_queue_depth_ops = {
+ .set = io_queue_depth_set,
+ .get = param_get_int,
+};
+
+static int io_queue_depth = 1024;
+module_param_cb(io_queue_depth, &io_queue_depth_ops, &io_queue_depth, 0644);
+MODULE_PARM_DESC(io_queue_depth, "set io queue depth, should >= 2");
+
struct nvme_dev;
struct nvme_queue;
@@ -104,6 +113,17 @@ struct nvme_dev {
void **host_mem_desc_bufs;
};
+static int io_queue_depth_set(const char *val, const struct kernel_param *kp)
+{
+ int n = 0, ret;
+
+ ret = kstrtoint(val, 10, &n);
+ if (ret != 0 || n < 2)
+ return -EINVAL;
+
+ return param_set_int(val, kp);
+}
+
static inline unsigned int sq_idx(unsigned int qid, u32 stride)
{
return qid * 2 * stride;
@@ -1892,8 +1912,7 @@ static int nvme_pci_enable(struct nvme_dev *dev)
dev->ctrl.cap = lo_hi_readq(dev->bar + NVME_REG_CAP);
- dev->q_depth = min_t(int, NVME_CAP_MQES(dev->ctrl.cap) + 1,
- NVME_Q_DEPTH);
+ dev->q_depth = min_t(int, NVME_CAP_MQES(cap) + 1, io_queue_depth);
dev->db_stride = 1 << NVME_CAP_STRIDE(dev->ctrl.cap);
dev->dbs = dev->bar + 4096;
--
2.9.4
More information about the Linux-nvme
mailing list