staging/rdma/hfi1: Method to toggle "fast ECN" detection
Add a per port sysfs paramter to toggle cc_prescan/Fast ECN Detection and
remove the Kconfig option which was previously used to control this.
While am updating the sysfs documentation, fix the name of CCMgtA.
Reviewed-by: Arthur Kepner <arthur.kepner@intel.com>
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Vennila Megavannan <vennila.megavannan@intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
diff --git a/drivers/staging/rdma/hfi1/Kconfig b/drivers/staging/rdma/hfi1/Kconfig
index 846c240c..3e668d8 100644
--- a/drivers/staging/rdma/hfi1/Kconfig
+++ b/drivers/staging/rdma/hfi1/Kconfig
@@ -26,13 +26,3 @@
---help---
This is a configuration flag to enable verbose
SDMA debug
-config PRESCAN_RXQ
- bool "Enable prescanning of the RX queue for ECNs"
- depends on INFINIBAND_HFI1
- default n
- ---help---
- This option toggles the prescanning of the receive queue for
- Explicit Congestion Notifications. If an ECN is detected, it
- is processed as quickly as possible, the ECN is toggled off.
- After the prescanning step, the receive queue is processed as
- usual.
diff --git a/drivers/staging/rdma/hfi1/driver.c b/drivers/staging/rdma/hfi1/driver.c
index d848cc0..59ce85f 100644
--- a/drivers/staging/rdma/hfi1/driver.c
+++ b/drivers/staging/rdma/hfi1/driver.c
@@ -453,11 +453,6 @@
packet->rcv_flags = 0;
}
-#ifndef CONFIG_PRESCAN_RXQ
-static void prescan_rxq(struct hfi1_packet *packet) {}
-#else /* !CONFIG_PRESCAN_RXQ */
-static int prescan_receive_queue;
-
static void process_ecn(struct rvt_qp *qp, struct hfi1_ib_header *hdr,
struct hfi1_other_headers *ohdr,
u64 rhf, u32 bth1, struct ib_grh *grh)
@@ -581,15 +576,19 @@
* containing Excplicit Congestion Notifications (FECNs, or BECNs).
* When an ECN is found, process the Congestion Notification, and toggle
* it off.
+ * This is declared as a macro to allow quick checking of the port to avoid
+ * the overhead of a function call if not enabled.
*/
-static void prescan_rxq(struct hfi1_packet *packet)
+#define prescan_rxq(rcd, packet) \
+ do { \
+ if (rcd->ppd->cc_prescan) \
+ __prescan_rxq(packet); \
+ } while (0)
+static void __prescan_rxq(struct hfi1_packet *packet)
{
struct hfi1_ctxtdata *rcd = packet->rcd;
struct ps_mdata mdata;
- if (!prescan_receive_queue)
- return;
-
init_ps_mdata(&mdata, packet);
while (1) {
@@ -653,7 +652,6 @@
update_ps_mdata(&mdata, rcd);
}
}
-#endif /* CONFIG_PRESCAN_RXQ */
static inline int skip_rcv_packet(struct hfi1_packet *packet, int thread)
{
@@ -819,7 +817,7 @@
goto bail;
}
- prescan_rxq(&packet);
+ prescan_rxq(rcd, &packet);
while (last == RCV_PKT_OK) {
last = process_rcv_packet(&packet, thread);
@@ -850,7 +848,7 @@
}
smp_rmb(); /* prevent speculative reads of dma'ed hdrq */
- prescan_rxq(&packet);
+ prescan_rxq(rcd, &packet);
while (last == RCV_PKT_OK) {
last = process_rcv_packet(&packet, thread);
@@ -961,7 +959,7 @@
}
}
- prescan_rxq(&packet);
+ prescan_rxq(rcd, &packet);
while (last == RCV_PKT_OK) {
diff --git a/drivers/staging/rdma/hfi1/hfi.h b/drivers/staging/rdma/hfi1/hfi.h
index 76c369a..d19d6b7 100644
--- a/drivers/staging/rdma/hfi1/hfi.h
+++ b/drivers/staging/rdma/hfi1/hfi.h
@@ -734,6 +734,8 @@
/* Error events that will cause a port bounce. */
u32 port_error_action;
struct work_struct linkstate_active_work;
+ /* Does this port need to prescan for FECNs */
+ bool cc_prescan;
};
typedef int (*rhf_rcv_function_ptr)(struct hfi1_packet *packet);
diff --git a/drivers/staging/rdma/hfi1/sysfs.c b/drivers/staging/rdma/hfi1/sysfs.c
index d05b9f3..f1d47e7 100644
--- a/drivers/staging/rdma/hfi1/sysfs.c
+++ b/drivers/staging/rdma/hfi1/sysfs.c
@@ -99,10 +99,6 @@
/* nothing to do since memory is freed by hfi1_free_devdata() */
}
-static struct kobj_type port_cc_ktype = {
- .release = port_release,
-};
-
static struct bin_attribute cc_table_bin_attr = {
.attr = {.name = "cc_table_bin", .mode = 0444},
.read = read_cc_table_bin,
@@ -151,6 +147,68 @@
.size = PAGE_SIZE,
};
+struct hfi1_port_attr {
+ struct attribute attr;
+ ssize_t (*show)(struct hfi1_pportdata *, char *);
+ ssize_t (*store)(struct hfi1_pportdata *, const char *, size_t);
+};
+
+static ssize_t cc_prescan_show(struct hfi1_pportdata *ppd, char *buf)
+{
+ return sprintf(buf, "%s\n", ppd->cc_prescan ? "on" : "off");
+}
+
+static ssize_t cc_prescan_store(struct hfi1_pportdata *ppd, const char *buf,
+ size_t count)
+{
+ if (!memcmp(buf, "on", 2))
+ ppd->cc_prescan = true;
+ else if (!memcmp(buf, "off", 3))
+ ppd->cc_prescan = false;
+
+ return count;
+}
+
+static struct hfi1_port_attr cc_prescan_attr =
+ __ATTR(cc_prescan, 0600, cc_prescan_show, cc_prescan_store);
+
+static ssize_t cc_attr_show(struct kobject *kobj, struct attribute *attr,
+ char *buf)
+{
+ struct hfi1_port_attr *port_attr =
+ container_of(attr, struct hfi1_port_attr, attr);
+ struct hfi1_pportdata *ppd =
+ container_of(kobj, struct hfi1_pportdata, pport_cc_kobj);
+
+ return port_attr->show(ppd, buf);
+}
+
+static ssize_t cc_attr_store(struct kobject *kobj, struct attribute *attr,
+ const char *buf, size_t count)
+{
+ struct hfi1_port_attr *port_attr =
+ container_of(attr, struct hfi1_port_attr, attr);
+ struct hfi1_pportdata *ppd =
+ container_of(kobj, struct hfi1_pportdata, pport_cc_kobj);
+
+ return port_attr->store(ppd, buf, count);
+}
+
+static const struct sysfs_ops port_cc_sysfs_ops = {
+ .show = cc_attr_show,
+ .store = cc_attr_store
+};
+
+static struct attribute *port_cc_default_attributes[] = {
+ &cc_prescan_attr.attr
+};
+
+static struct kobj_type port_cc_ktype = {
+ .release = port_release,
+ .sysfs_ops = &port_cc_sysfs_ops,
+ .default_attrs = port_cc_default_attributes
+};
+
/* Start sc2vl */
#define HFI1_SC2VL_ATTR(N) \
static struct hfi1_sc2vl_attr hfi1_sc2vl_attr_##N = { \