From 7bb312e4a2f323fa460bbf9f33eeb00b5dabdb6b Mon Sep 17 00:00:00 2001 From: Vu Pham Date: Sat, 26 Oct 2013 14:31:27 +0200 Subject: IB/srp: Make transport layer retry count configurable Allow the InfiniBand RC retry count to be configured by the user as an option in the target login string. Reducing this retry count allows to reduce the path failover time. Signed-off-by: Vu Pham [ bvanassche: Rewrote patch description / changed default retry count ] Signed-off-by: Bart Van Assche Acked-by: David Dillow Signed-off-by: Roland Dreier diff --git a/Documentation/ABI/stable/sysfs-driver-ib_srp b/Documentation/ABI/stable/sysfs-driver-ib_srp index 5c53d28..18e9b27 100644 --- a/Documentation/ABI/stable/sysfs-driver-ib_srp +++ b/Documentation/ABI/stable/sysfs-driver-ib_srp @@ -61,6 +61,8 @@ Description: Interface for making ib_srp connect to a new target. interrupt is handled by a different CPU then the comp_vector parameter can be used to spread the SRP completion workload over multiple CPU's. + * tl_retry_count, a number in the range 2..7 specifying the + IB RC retry count. What: /sys/class/infiniband_srp/srp--/ibdev Date: January 2, 2006 diff --git a/drivers/infiniband/ulp/srp/ib_srp.c b/drivers/infiniband/ulp/srp/ib_srp.c index f93baf8..11ebf3e 100644 --- a/drivers/infiniband/ulp/srp/ib_srp.c +++ b/drivers/infiniband/ulp/srp/ib_srp.c @@ -390,7 +390,7 @@ static int srp_send_req(struct srp_target_port *target) req->param.responder_resources = 4; req->param.remote_cm_response_timeout = 20; req->param.local_cm_response_timeout = 20; - req->param.retry_count = 7; + req->param.retry_count = target->tl_retry_count; req->param.rnr_retry_count = 7; req->param.max_cm_retries = 15; @@ -1907,6 +1907,14 @@ static ssize_t show_comp_vector(struct device *dev, return sprintf(buf, "%d\n", target->comp_vector); } +static ssize_t show_tl_retry_count(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct srp_target_port *target = host_to_target(class_to_shost(dev)); + + return sprintf(buf, "%d\n", target->tl_retry_count); +} + static ssize_t show_cmd_sg_entries(struct device *dev, struct device_attribute *attr, char *buf) { @@ -1934,6 +1942,7 @@ static DEVICE_ATTR(zero_req_lim, S_IRUGO, show_zero_req_lim, NULL); static DEVICE_ATTR(local_ib_port, S_IRUGO, show_local_ib_port, NULL); static DEVICE_ATTR(local_ib_device, S_IRUGO, show_local_ib_device, NULL); static DEVICE_ATTR(comp_vector, S_IRUGO, show_comp_vector, NULL); +static DEVICE_ATTR(tl_retry_count, S_IRUGO, show_tl_retry_count, NULL); static DEVICE_ATTR(cmd_sg_entries, S_IRUGO, show_cmd_sg_entries, NULL); static DEVICE_ATTR(allow_ext_sg, S_IRUGO, show_allow_ext_sg, NULL); @@ -1949,6 +1958,7 @@ static struct device_attribute *srp_host_attrs[] = { &dev_attr_local_ib_port, &dev_attr_local_ib_device, &dev_attr_comp_vector, + &dev_attr_tl_retry_count, &dev_attr_cmd_sg_entries, &dev_attr_allow_ext_sg, NULL @@ -2073,6 +2083,7 @@ enum { SRP_OPT_ALLOW_EXT_SG = 1 << 10, SRP_OPT_SG_TABLESIZE = 1 << 11, SRP_OPT_COMP_VECTOR = 1 << 12, + SRP_OPT_TL_RETRY_COUNT = 1 << 13, SRP_OPT_ALL = (SRP_OPT_ID_EXT | SRP_OPT_IOC_GUID | SRP_OPT_DGID | @@ -2094,6 +2105,7 @@ static const match_table_t srp_opt_tokens = { { SRP_OPT_ALLOW_EXT_SG, "allow_ext_sg=%u" }, { SRP_OPT_SG_TABLESIZE, "sg_tablesize=%u" }, { SRP_OPT_COMP_VECTOR, "comp_vector=%u" }, + { SRP_OPT_TL_RETRY_COUNT, "tl_retry_count=%u" }, { SRP_OPT_ERR, NULL } }; @@ -2257,6 +2269,15 @@ static int srp_parse_options(const char *buf, struct srp_target_port *target) target->comp_vector = token; break; + case SRP_OPT_TL_RETRY_COUNT: + if (match_int(args, &token) || token < 2 || token > 7) { + pr_warn("bad tl_retry_count parameter '%s' (must be a number between 2 and 7)\n", + p); + goto out; + } + target->tl_retry_count = token; + break; + default: pr_warn("unknown parameter or missing value '%s' in target creation request\n", p); @@ -2311,6 +2332,7 @@ static ssize_t srp_create_target(struct device *dev, target->cmd_sg_cnt = cmd_sg_entries; target->sg_tablesize = indirect_sg_entries ? : cmd_sg_entries; target->allow_ext_sg = allow_ext_sg; + target->tl_retry_count = 7; ret = srp_parse_options(buf, target); if (ret) diff --git a/drivers/infiniband/ulp/srp/ib_srp.h b/drivers/infiniband/ulp/srp/ib_srp.h index e641088..84d821b 100644 --- a/drivers/infiniband/ulp/srp/ib_srp.h +++ b/drivers/infiniband/ulp/srp/ib_srp.h @@ -157,6 +157,7 @@ struct srp_target_port { unsigned int scsi_id; unsigned int sg_tablesize; int comp_vector; + int tl_retry_count; struct ib_sa_path_rec path; __be16 orig_dgid[8]; -- cgit v0.10.2