Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
nvme-pci: remove last_sq_tail
The nvme driver does not have enough tags to wrap the queue, and blk-mq
will no longer call commit_rqs() when there are no new submissions to
notify.
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
authored by
Keith Busch
and committed by
Jens Axboe
54b2fcee
74943d45
+4
-19
+4
-19
drivers/nvme/host/pci.c
+4
-19
drivers/nvme/host/pci.c
···
173
173
u16 q_depth;
174
174
u16 cq_vector;
175
175
u16 sq_tail;
176
-
u16 last_sq_tail;
177
176
u16 cq_head;
178
177
u16 qid;
179
178
u8 cq_phase;
···
445
446
return 0;
446
447
}
447
448
448
-
/*
449
-
* Write sq tail if we are asked to, or if the next command would wrap.
450
-
*/
451
-
static inline void nvme_write_sq_db(struct nvme_queue *nvmeq, bool write_sq)
449
+
static inline void nvme_write_sq_db(struct nvme_queue *nvmeq)
452
450
{
453
-
if (!write_sq) {
454
-
u16 next_tail = nvmeq->sq_tail + 1;
455
-
456
-
if (next_tail == nvmeq->q_depth)
457
-
next_tail = 0;
458
-
if (next_tail != nvmeq->last_sq_tail)
459
-
return;
460
-
}
461
-
462
451
if (nvme_dbbuf_update_and_check_event(nvmeq->sq_tail,
463
452
nvmeq->dbbuf_sq_db, nvmeq->dbbuf_sq_ei))
464
453
writel(nvmeq->sq_tail, nvmeq->q_db);
465
-
nvmeq->last_sq_tail = nvmeq->sq_tail;
466
454
}
467
455
468
456
/**
···
466
480
cmd, sizeof(*cmd));
467
481
if (++nvmeq->sq_tail == nvmeq->q_depth)
468
482
nvmeq->sq_tail = 0;
469
-
nvme_write_sq_db(nvmeq, write_sq);
483
+
if (write_sq)
484
+
nvme_write_sq_db(nvmeq);
470
485
spin_unlock(&nvmeq->sq_lock);
471
486
}
472
487
···
476
489
struct nvme_queue *nvmeq = hctx->driver_data;
477
490
478
491
spin_lock(&nvmeq->sq_lock);
479
-
if (nvmeq->sq_tail != nvmeq->last_sq_tail)
480
-
nvme_write_sq_db(nvmeq, true);
492
+
nvme_write_sq_db(nvmeq);
481
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spin_unlock(&nvmeq->sq_lock);
482
494
}
483
495
···
1480
1494
struct nvme_dev *dev = nvmeq->dev;
1481
1495
1482
1496
nvmeq->sq_tail = 0;
1483
-
nvmeq->last_sq_tail = 0;
1484
1497
nvmeq->cq_head = 0;
1485
1498
nvmeq->cq_phase = 1;
1486
1499
nvmeq->q_db = &dev->dbs[qid * 2 * dev->db_stride];