ib_srpt: Convert to percpu_ida tag allocation

This patch converts ib_srpt to use existing percpu_ida tag
pre-allocation for struct srpt_send_ioctx.

This allows ib_srpt to drop it's internal pre-allocation
mechanisms with the extra spin_lock_irqsave, and use
percpu_ida common code for doing this.

Cc: Vu Pham <vu@mellanox.com>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This commit is contained in:
Nicholas Bellinger 2016-01-29 22:47:58 -08:00
parent 91973cd60e
commit 0fd10721fe
2 changed files with 17 additions and 40 deletions

View File

@ -1261,40 +1261,26 @@ static int srpt_map_sg_to_ib_sge(struct srpt_rdma_ch *ch,
*/
static struct srpt_send_ioctx *srpt_get_send_ioctx(struct srpt_rdma_ch *ch)
{
struct se_session *se_sess;
struct srpt_send_ioctx *ioctx;
unsigned long flags;
int tag;
BUG_ON(!ch);
se_sess = ch->sess;
ioctx = NULL;
spin_lock_irqsave(&ch->spinlock, flags);
if (!list_empty(&ch->free_list)) {
ioctx = list_first_entry(&ch->free_list,
struct srpt_send_ioctx, free_list);
list_del(&ioctx->free_list);
tag = percpu_ida_alloc(&se_sess->sess_tag_pool, TASK_RUNNING);
if (tag < 0) {
pr_err("Unable to obtain tag for srpt_send_ioctx\n");
return NULL;
}
spin_unlock_irqrestore(&ch->spinlock, flags);
if (!ioctx)
return ioctx;
BUG_ON(ioctx->ch != ch);
ioctx = &((struct srpt_send_ioctx *)se_sess->sess_cmd_map)[tag];
memset(ioctx, 0, sizeof(struct srpt_send_ioctx));
ioctx->ch = ch;
spin_lock_init(&ioctx->spinlock);
ioctx->state = SRPT_STATE_NEW;
ioctx->n_rbuf = 0;
ioctx->rbufs = NULL;
ioctx->n_rdma = 0;
ioctx->n_rdma_wrs = 0;
ioctx->rdma_wrs = NULL;
ioctx->mapped_sg_count = 0;
init_completion(&ioctx->tx_done);
ioctx->queue_status_only = false;
/*
* transport_init_se_cmd() does not initialize all fields, so do it
* here.
*/
memset(&ioctx->cmd, 0, sizeof(ioctx->cmd));
memset(&ioctx->sense_data, 0, sizeof(ioctx->sense_data));
ioctx->cmd.map_tag = tag;
return ioctx;
}
@ -2241,7 +2227,7 @@ static int srpt_cm_req_recv(struct ib_cm_id *cm_id,
struct ib_cm_rep_param *rep_param;
struct srpt_rdma_ch *ch, *tmp_ch;
u32 it_iu_len;
int i, ret = 0;
int ret = 0;
unsigned char *p;
WARN_ON_ONCE(irqs_disabled());
@ -2370,12 +2356,6 @@ static int srpt_cm_req_recv(struct ib_cm_id *cm_id,
if (!ch->ioctx_ring)
goto free_ch;
INIT_LIST_HEAD(&ch->free_list);
for (i = 0; i < ch->rq_size; i++) {
ch->ioctx_ring[i]->ch = ch;
list_add_tail(&ch->ioctx_ring[i]->free_list, &ch->free_list);
}
ret = srpt_create_ch_ib(ch);
if (ret) {
rej->reason = cpu_to_be32(
@ -2406,7 +2386,8 @@ static int srpt_cm_req_recv(struct ib_cm_id *cm_id,
p = &ch->sess_name[0];
try_again:
ch->sess = target_alloc_session(&sport->port_tpg_1, 0, 0,
ch->sess = target_alloc_session(&sport->port_tpg_1, ch->rq_size,
sizeof(struct srpt_send_ioctx),
TARGET_PROT_NORMAL, p, ch, NULL);
if (IS_ERR(ch->sess)) {
pr_info("Rejected login because no ACL has been"
@ -3194,7 +3175,7 @@ static void srpt_release_cmd(struct se_cmd *se_cmd)
struct srpt_send_ioctx *ioctx = container_of(se_cmd,
struct srpt_send_ioctx, cmd);
struct srpt_rdma_ch *ch = ioctx->ch;
unsigned long flags;
struct se_session *se_sess = ch->sess;
WARN_ON(ioctx->state != SRPT_STATE_DONE);
WARN_ON(ioctx->mapped_sg_count != 0);
@ -3205,9 +3186,7 @@ static void srpt_release_cmd(struct se_cmd *se_cmd)
ioctx->n_rbuf = 0;
}
spin_lock_irqsave(&ch->spinlock, flags);
list_add(&ioctx->free_list, &ch->free_list);
spin_unlock_irqrestore(&ch->spinlock, flags);
percpu_ida_free(&se_sess->sess_tag_pool, se_cmd->map_tag);
}
/**

View File

@ -179,7 +179,6 @@ struct srpt_recv_ioctx {
* struct srpt_send_ioctx - SRPT send I/O context.
* @ioctx: See above.
* @ch: Channel pointer.
* @free_list: Node in srpt_rdma_ch.free_list.
* @n_rbuf: Number of data buffers in the received SRP command.
* @rbufs: Pointer to SRP data buffer array.
* @single_rbuf: SRP data buffer if the command has only a single buffer.
@ -202,7 +201,6 @@ struct srpt_send_ioctx {
struct srp_direct_buf *rbufs;
struct srp_direct_buf single_rbuf;
struct scatterlist *sg;
struct list_head free_list;
spinlock_t spinlock;
enum srpt_command_state state;
struct se_cmd cmd;