2013-10-10 18:30:00

by Matias Bjørling

Subject: [PATCH 0/2] NVMe: Refactoring

Two refactor patches that increases the code clarity.

The to-be blk-mq proposal patchset utilizes these as part of its transformation.
They are also useful for the current codebase and therefore submitted upfront.

Matias Bjorling (2):
NVMe: Refactor doorbell
NVMe: Extract admin queue size

drivers/block/nvme-core.c | 32 +++++++++++++++-----------------
1 file changed, 15 insertions(+), 17 deletions(-)

--
1.8.1.2

2013-10-10 18:30:05

by Matias Bjørling

Subject: [PATCH 2/2] NVMe: Extract admin queue size

The queue size of the admin queue should be defined as a constant for use in
multiple places.

Signed-off-by: Matias Bjorling <[email protected]>
---
drivers/block/nvme-core.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c
index 1e940e8..d4f01d4 100644
--- a/drivers/block/nvme-core.c
+++ b/drivers/block/nvme-core.c
@@ -44,6 +44,7 @@
#include <asm-generic/io-64-nonatomic-lo-hi.h>

#define NVME_Q_DEPTH 1024
+#define NVME_ADMIN_Q_DEPTH 64
#define SQ_SIZE(depth) (depth * sizeof(struct nvme_command))
#define CQ_SIZE(depth) (depth * sizeof(struct nvme_completion))
#define NVME_MINORS 64
@@ -1261,7 +1262,7 @@ static int nvme_configure_admin_queue(struct nvme_dev *dev)

nvmeq = dev->queues[0];
if (!nvmeq) {
- nvmeq = nvme_alloc_queue(dev, 0, 64, 0);
+ nvmeq = nvme_alloc_queue(dev, 0, NVME_ADMIN_Q_DEPTH, 0);
if (!nvmeq)
return -ENOMEM;
dev->queues[0] = nvmeq;
--
1.8.1.2

2013-10-10 18:30:03

by Matias Bjørling

Subject: [PATCH 1/2] NVMe: Refactor doorbell

The doorbell code is repeated various places. Refactor it into its own function
for clarity.

Signed-off-by: Matias Bjorling <[email protected]>
---
drivers/block/nvme-core.c | 29 +++++++++++++----------------
1 file changed, 13 insertions(+), 16 deletions(-)

diff --git a/drivers/block/nvme-core.c b/drivers/block/nvme-core.c
index da52092..1e940e8 100644
--- a/drivers/block/nvme-core.c
+++ b/drivers/block/nvme-core.c
@@ -242,6 +242,13 @@ void put_nvmeq(struct nvme_queue *nvmeq)
put_cpu();
}

+static inline void nvme_ring_doorbell(struct nvme_queue *nvmeq)
+{
+ if (++nvmeq->sq_tail == nvmeq->q_depth)
+ nvmeq->sq_tail = 0;
+ writel(nvmeq->sq_tail, nvmeq->q_db);
+}
+
/**
* nvme_submit_cmd() - Copy a command into a queue and ring the doorbell
* @nvmeq: The queue to use
@@ -252,14 +259,10 @@ void put_nvmeq(struct nvme_queue *nvmeq)
static int nvme_submit_cmd(struct nvme_queue *nvmeq, struct nvme_command *cmd)
{
unsigned long flags;
- u16 tail;
+
spin_lock_irqsave(&nvmeq->q_lock, flags);
- tail = nvmeq->sq_tail;
- memcpy(&nvmeq->sq_cmds[tail], cmd, sizeof(*cmd));
- if (++tail == nvmeq->q_depth)
- tail = 0;
- writel(tail, nvmeq->q_db);
- nvmeq->sq_tail = tail;
+ memcpy(&nvmeq->sq_cmds[nvmeq->sqtail], cmd, sizeof(*cmd));
+ nvme_ring_doorbell(nvmeq);
spin_unlock_irqrestore(&nvmeq->q_lock, flags);

return 0;
@@ -619,9 +622,7 @@ static int nvme_submit_discard(struct nvme_queue *nvmeq, struct nvme_ns *ns,
cmnd->dsm.nr = 0;
cmnd->dsm.attributes = cpu_to_le32(NVME_DSMGMT_AD);

- if (++nvmeq->sq_tail == nvmeq->q_depth)
- nvmeq->sq_tail = 0;
- writel(nvmeq->sq_tail, nvmeq->q_db);
+ nvme_ring_doorbell(nvmeq);

return 0;
}
@@ -636,9 +637,7 @@ static int nvme_submit_flush(struct nvme_queue *nvmeq, struct nvme_ns *ns,
cmnd->common.command_id = cmdid;
cmnd->common.nsid = cpu_to_le32(ns->ns_id);

- if (++nvmeq->sq_tail == nvmeq->q_depth)
- nvmeq->sq_tail = 0;
- writel(nvmeq->sq_tail, nvmeq->q_db);
+ nvme_ring_doorbell(nvmeq);

return 0;
}
@@ -729,9 +728,7 @@ static int nvme_submit_bio_queue(struct nvme_queue *nvmeq, struct nvme_ns *ns,
cmnd->rw.dsmgmt = cpu_to_le32(dsmgmt);

nvme_start_io_acct(bio);
- if (++nvmeq->sq_tail == nvmeq->q_depth)
- nvmeq->sq_tail = 0;
- writel(nvmeq->sq_tail, nvmeq->q_db);
+ nvme_ring_doorbell(nvmeq);

return 0;

--
1.8.1.2