IB/qib: Add congestion control agent implementation

Add a congestion control agent in the driver that handles gets and
sets from the congestion control manager in the fabric for the
Performance Scale Messaging (PSM) library.

Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

1 files changed, 149 insertions, 9 deletions

diff --git a/drivers/infiniband/hw/qib/qib_sysfs.c b/drivers/infiniband/hw/qib/qib_sysfs.c
index dd9cd49d0979..ae78305b59d0 100644
--- a/drivers/infiniband/hw/qib/qib_sysfs.c
+++ b/drivers/infiniband/hw/qib/qib_sysfs.c
@@ -1,5 +1,6 @@
 /*
- * Copyright (c) 2006, 2007, 2008, 2009 QLogic Corporation. All rights reserved.
+ * Copyright (c) 2012 Intel Corporation.  All rights reserved.
+ * Copyright (c) 2006 - 2012 QLogic Corporation. All rights reserved.
  * Copyright (c) 2006 PathScale, Inc. All rights reserved.
  *
  * This software is available to you under a choice of one of two
@@ -33,6 +34,7 @@
 #include <linux/ctype.h>
 
 #include "qib.h"
+#include "qib_mad.h"
 
 /**
  * qib_parse_ushort - parse an unsigned short value in an arbitrary base
@@ -231,6 +233,98 @@ static struct attribute *port_default_attributes[] = {
 	NULL
 };
 
+/*
+ * Start of per-port congestion control structures and support code
+ */
+
+/*
+ * Congestion control table size followed by table entries
+ */
+static ssize_t read_cc_table_bin(struct file *filp, struct kobject *kobj,
+		struct bin_attribute *bin_attr,
+		char *buf, loff_t pos, size_t count)
+{
+	int ret;
+	struct qib_pportdata *ppd =
+		container_of(kobj, struct qib_pportdata, pport_cc_kobj);
+
+	if (!qib_cc_table_size || !ppd->ccti_entries_shadow)
+		return -EINVAL;
+
+	ret = ppd->total_cct_entry * sizeof(struct ib_cc_table_entry_shadow)
+		 + sizeof(__be16);
+
+	if (pos > ret)
+		return -EINVAL;
+
+	if (count > ret - pos)
+		count = ret - pos;
+
+	if (!count)
+		return count;
+
+	spin_lock(&ppd->cc_shadow_lock);
+	memcpy(buf, ppd->ccti_entries_shadow, count);
+	spin_unlock(&ppd->cc_shadow_lock);
+
+	return count;
+}
+
+static void qib_port_release(struct kobject *kobj)
+{
+	/* nothing to do since memory is freed by qib_free_devdata() */
+}
+
+static struct kobj_type qib_port_cc_ktype = {
+	.release = qib_port_release,
+};
+
+static struct bin_attribute cc_table_bin_attr = {
+	.attr = {.name = "cc_table_bin", .mode = 0444},
+	.read = read_cc_table_bin,
+	.size = PAGE_SIZE,
+};
+
+/*
+ * Congestion settings: port control, control map and an array of 16
+ * entries for the congestion entries - increase, timer, event log
+ * trigger threshold and the minimum injection rate delay.
+ */
+static ssize_t read_cc_setting_bin(struct file *filp, struct kobject *kobj,
+		struct bin_attribute *bin_attr,
+		char *buf, loff_t pos, size_t count)
+{
+	int ret;
+	struct qib_pportdata *ppd =
+		container_of(kobj, struct qib_pportdata, pport_cc_kobj);
+
+	if (!qib_cc_table_size || !ppd->congestion_entries_shadow)
+		return -EINVAL;
+
+	ret = sizeof(struct ib_cc_congestion_setting_attr_shadow);
+
+	if (pos > ret)
+		return -EINVAL;
+	if (count > ret - pos)
+		count = ret - pos;
+
+	if (!count)
+		return count;
+
+	spin_lock(&ppd->cc_shadow_lock);
+	memcpy(buf, ppd->congestion_entries_shadow, count);
+	spin_unlock(&ppd->cc_shadow_lock);
+
+	return count;
+}
+
+static struct bin_attribute cc_setting_bin_attr = {
+	.attr = {.name = "cc_settings_bin", .mode = 0444},
+	.read = read_cc_setting_bin,
+	.size = PAGE_SIZE,
+};
+
+
 static ssize_t qib_portattr_show(struct kobject *kobj,
 	struct attribute *attr, char *buf)
 {
@@ -253,10 +347,6 @@ static ssize_t qib_portattr_store(struct kobject *kobj,
 	return pattr->store(ppd, buf, len);
 }
 
-static void qib_port_release(struct kobject *kobj)
-{
-	/* nothing to do since memory is freed by qib_free_devdata() */
-}
 
 static const struct sysfs_ops qib_port_ops = {
 	.show = qib_portattr_show,
@@ -670,7 +760,7 @@ int qib_create_port_files(struct ib_device *ibdev, u8 port_num,
 	if (ret) {
 		qib_dev_err(dd, "Skipping sl2vl sysfs info, "
 			    "(err %d) port %u\n", ret, port_num);
-		goto bail_sl;
+		goto bail_link;
 	}
 	kobject_uevent(&ppd->sl2vl_kobj, KOBJ_ADD);
 
@@ -679,15 +769,57 @@ int qib_create_port_files(struct ib_device *ibdev, u8 port_num,
 	if (ret) {
 		qib_dev_err(dd, "Skipping diag_counters sysfs info, "
 			    "(err %d) port %u\n", ret, port_num);
-		goto bail_diagc;
+		goto bail_sl;
 	}
 	kobject_uevent(&ppd->diagc_kobj, KOBJ_ADD);
 
+	if (!qib_cc_table_size || !ppd->congestion_entries_shadow)
+		return 0;
+
+	ret = kobject_init_and_add(&ppd->pport_cc_kobj, &qib_port_cc_ktype,
+				kobj, "CCMgtA");
+	if (ret) {
+		qib_dev_err(dd,
+		 "Skipping Congestion Control sysfs info, (err %d) port %u\n",
+		 ret, port_num);
+		goto bail_diagc;
+	}
+
+	kobject_uevent(&ppd->pport_cc_kobj, KOBJ_ADD);
+
+	ret = sysfs_create_bin_file(&ppd->pport_cc_kobj,
+				&cc_setting_bin_attr);
+	if (ret) {
+		qib_dev_err(dd,
+		 "Skipping Congestion Control setting sysfs info, (err %d) port %u\n",
+		 ret, port_num);
+		goto bail_cc;
+	}
+
+	ret = sysfs_create_bin_file(&ppd->pport_cc_kobj,
+				&cc_table_bin_attr);
+	if (ret) {
+		qib_dev_err(dd,
+		 "Skipping Congestion Control table sysfs info, (err %d) port %u\n",
+		 ret, port_num);
+		goto bail_cc_entry_bin;
+	}
+
+	qib_devinfo(dd->pcidev,
+		"IB%u: Congestion Control Agent enabled for port %d\n",
+		dd->unit, port_num);
+
 	return 0;
 
+bail_cc_entry_bin:
+	sysfs_remove_bin_file(&ppd->pport_cc_kobj, &cc_setting_bin_attr);
+bail_cc:
+	kobject_put(&ppd->pport_cc_kobj);
 bail_diagc:
-	kobject_put(&ppd->sl2vl_kobj);
+	kobject_put(&ppd->diagc_kobj);
 bail_sl:
+	kobject_put(&ppd->sl2vl_kobj);
+bail_link:
 	kobject_put(&ppd->pport_kobj);
 bail:
 	return ret;
@@ -720,7 +852,15 @@ void qib_verbs_unregister_sysfs(struct qib_devdata *dd)
 
 	for (i = 0; i < dd->num_pports; i++) {
 		ppd = &dd->pport[i];
-		kobject_put(&ppd->pport_kobj);
+		if (qib_cc_table_size &&
+			ppd->congestion_entries_shadow) {
+			sysfs_remove_bin_file(&ppd->pport_cc_kobj,
+				&cc_setting_bin_attr);
+			sysfs_remove_bin_file(&ppd->pport_cc_kobj,
+				&cc_table_bin_attr);
+			kobject_put(&ppd->pport_cc_kobj);
+		}
 		kobject_put(&ppd->sl2vl_kobj);
+		kobject_put(&ppd->pport_kobj);
 	}
 }