diff options
author | Arnd Bergmann <arnd@arndb.de> | 2018-12-10 22:34:39 +0100 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2018-12-10 14:44:56 -0700 |
commit | e4025e46f093d4549d3043c2c54d444cec480d2b (patch) | |
tree | d96d7141ef0bdcc4147fb55530b2d9857f7a93a7 /drivers/block | |
parent | 6f75723190d88e1319bea623bfe0292bf3917965 (diff) | |
download | linux-e4025e46f093d4549d3043c2c54d444cec480d2b.tar.bz2 |
mtip32xx: avoid using semaphores
The "cmd_slot_unal" semaphore is never used in a blocking way
but only as an atomic counter. Change the code to using
atomic_dec_if_positive() as a better API.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers/block')
-rw-r--r-- | drivers/block/mtip32xx/mtip32xx.c | 6 | ||||
-rw-r--r-- | drivers/block/mtip32xx/mtip32xx.h | 4 |
2 files changed, 5 insertions, 5 deletions
diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c index 2b0ac9d01e51..d7dc307d0cc8 100644 --- a/drivers/block/mtip32xx/mtip32xx.c +++ b/drivers/block/mtip32xx/mtip32xx.c @@ -2680,7 +2680,7 @@ static void mtip_softirq_done_fn(struct request *rq) cmd->direction); if (unlikely(cmd->unaligned)) - up(&dd->port->cmd_slot_unal); + atomic_inc(&dd->port->cmd_slot_unal); blk_mq_end_request(rq, cmd->status); } @@ -2990,7 +2990,7 @@ static int mtip_hw_init(struct driver_data *dd) else dd->unal_qdepth = 0; - sema_init(&dd->port->cmd_slot_unal, dd->unal_qdepth); + atomic_set(&dd->port->cmd_slot_unal, dd->unal_qdepth); /* Spinlock to prevent concurrent issue */ for (i = 0; i < MTIP_MAX_SLOT_GROUPS; i++) @@ -3533,7 +3533,7 @@ static bool mtip_check_unal_depth(struct blk_mq_hw_ctx *hctx, cmd->unaligned = 1; } - if (cmd->unaligned && down_trylock(&dd->port->cmd_slot_unal)) + if (cmd->unaligned && atomic_dec_if_positive(&dd->port->cmd_slot_unal) >= 0) return true; return false; diff --git a/drivers/block/mtip32xx/mtip32xx.h b/drivers/block/mtip32xx/mtip32xx.h index c33f8c3d9fb4..abce25f27f57 100644 --- a/drivers/block/mtip32xx/mtip32xx.h +++ b/drivers/block/mtip32xx/mtip32xx.h @@ -433,8 +433,8 @@ struct mtip_port { */ unsigned long ic_pause_timer; - /* Semaphore to control queue depth of unaligned IOs */ - struct semaphore cmd_slot_unal; + /* Counter to control queue depth of unaligned IOs */ + atomic_t cmd_slot_unal; /* Spinlock for working around command-issue bug. */ spinlock_t cmd_issue_lock[MTIP_MAX_SLOT_GROUPS]; |