4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Greg Kroah-Hartman gregkh@linuxfoundation.org
This reverts commit 9bf9e352ed51d4cdee107675609ba12b42d00c5b which was commit a4e84aae8139aca9fbfbced1f45c51ca81b57488 upstream.
Ben writes: MQ IO schedulers were introduced in 4.11, so this shouldn't be needed in older branches. It also causes a performance regression (fixed upstream). Please revert this for 4.4 and 4.9.
So let's revert it!
Reported-by: Ben Hutchings ben.hutchings@codethink.co.uk Cc: Ming Lei ming.lei@redhat.com Cc: Jens Axboe axboe@fb.com Cc: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/block/mtip32xx/mtip32xx.c | 36 ++++++++++++------------------------ 1 file changed, 12 insertions(+), 24 deletions(-)
--- a/drivers/block/mtip32xx/mtip32xx.c +++ b/drivers/block/mtip32xx/mtip32xx.c @@ -169,25 +169,6 @@ static bool mtip_check_surprise_removal( return false; /* device present */ }
-/* we have to use runtime tag to setup command header */ -static void mtip_init_cmd_header(struct request *rq) -{ - struct driver_data *dd = rq->q->queuedata; - struct mtip_cmd *cmd = blk_mq_rq_to_pdu(rq); - u32 host_cap_64 = readl(dd->mmio + HOST_CAP) & HOST_CAP_64; - - /* Point the command headers at the command tables. */ - cmd->command_header = dd->port->command_list + - (sizeof(struct mtip_cmd_hdr) * rq->tag); - cmd->command_header_dma = dd->port->command_list_dma + - (sizeof(struct mtip_cmd_hdr) * rq->tag); - - if (host_cap_64) - cmd->command_header->ctbau = __force_bit2int cpu_to_le32((cmd->command_dma >> 16) >> 16); - - cmd->command_header->ctba = __force_bit2int cpu_to_le32(cmd->command_dma & 0xFFFFFFFF); -} - static struct mtip_cmd *mtip_get_int_command(struct driver_data *dd) { struct request *rq; @@ -199,9 +180,6 @@ static struct mtip_cmd *mtip_get_int_com if (IS_ERR(rq)) return NULL;
- /* Internal cmd isn't submitted via .queue_rq */ - mtip_init_cmd_header(rq); - return blk_mq_rq_to_pdu(rq); }
@@ -3840,8 +3818,6 @@ static int mtip_queue_rq(struct blk_mq_h struct request *rq = bd->rq; int ret;
- mtip_init_cmd_header(rq); - if (unlikely(mtip_check_unal_depth(hctx, rq))) return BLK_MQ_RQ_QUEUE_BUSY;
@@ -3873,6 +3849,7 @@ static int mtip_init_cmd(void *data, str { struct driver_data *dd = data; struct mtip_cmd *cmd = blk_mq_rq_to_pdu(rq); + u32 host_cap_64 = readl(dd->mmio + HOST_CAP) & HOST_CAP_64;
/* * For flush requests, request_idx starts at the end of the @@ -3889,6 +3866,17 @@ static int mtip_init_cmd(void *data, str
memset(cmd->command, 0, CMD_DMA_ALLOC_SZ);
+ /* Point the command headers at the command tables. */ + cmd->command_header = dd->port->command_list + + (sizeof(struct mtip_cmd_hdr) * request_idx); + cmd->command_header_dma = dd->port->command_list_dma + + (sizeof(struct mtip_cmd_hdr) * request_idx); + + if (host_cap_64) + cmd->command_header->ctbau = __force_bit2int cpu_to_le32((cmd->command_dma >> 16) >> 16); + + cmd->command_header->ctba = __force_bit2int cpu_to_le32(cmd->command_dma & 0xFFFFFFFF); + sg_init_table(cmd->sg, MTIP_MAX_SG); return 0; }