/*
* Copyright (c) 2016, Mellanox Technologies. All rights reserved.
*
* This software is available to you under a choice of one of two
* licenses. You may choose to be licensed under the terms of the GNU
* General Public License (GPL) Version 2, available from the file
* COPYING in the main directory of this source tree, or the
* OpenIB.org BSD license below:
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* - Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
*
* - Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include <linux/mlx5/driver.h>
#include <linux/mlx5/fs.h>
#include <linux/rbtree.h>
#include "mlx5_core.h"
#include "fs_core.h"
#include "fs_cmd.h"
#define MLX5_FC_STATS_PERIOD msecs_to_jiffies(1000)
/* Max number of counters to query in bulk read is 32K */
#define MLX5_SW_MAX_COUNTERS_BULK BIT(15)
struct mlx5_fc_cache {
u64 packets;
u64 bytes;
u64 lastuse;
};
struct mlx5_fc {
struct list_head list;
struct llist_node addlist;
struct llist_node dellist;
/* last{packets,bytes} members are used when calculating the delta since
* last reading
*/
u64 lastpackets;
u64 lastbytes;
u32 id;
bool aging;
struct mlx5_fc_cache cache ____cacheline_aligned_in_smp;
};
/* locking scheme:
*
* It is the responsibility of the user to prevent concurrent calls or bad
* ordering to mlx5_fc_create(), mlx5_fc_destroy() and accessing a reference
* to struct mlx5_fc.
* e.g en_tc.c is protected by RTNL lock of its caller, and will never call a
* dump (access to struct mlx5_fc) after a counter is destroyed.
*
* access to counter list:
* - create (user context)
* - mlx5_fc_create() only adds to an addlist to be used by
* mlx5_fc_stats_query_work(). addlist is a lockless single linked list
* that doesn't require any additional synchronization when adding single
* node.
* - spawn thread to do the actual destroy
*
* - destroy (user context)
* - add a counter to lockless dellist
* - spawn thread to do the actual del
*
* - dump (user context)
* user should not call dump after destroy
*
* - query (single thread workqueue context)
* destroy/dump - no conflict (see destroy)
* query/dump - packets and bytes might be inconsistent (since update is not
* atomic)
* query/create - no conflict (see create)
* since every create/destroy spawn the work, only after necessary time has
* elapsed, the thread will actually query the hardware.
*/
static struct list_head *mlx5_fc_counters_lookup_next(struct mlx5_core_dev *dev,
u32 id)
{
struct mlx5_fc_stats *fc_stats = &dev->priv.fc_stats;
unsigned long next_id = (unsigned long)id + 1;
struct mlx5_fc *counter;
unsigned long tmp;
rcu_read_lock();
/* skip counters that are in idr, but not yet in counters list */
idr_for_each_entry_continue_ul(&fc_stats->counters_idr,
counter, tmp, next_id) {
if (!list_empty(&counter->list))
break;
}
rcu_read_unlock();
return counter ? &counter->list : &fc_stats->counters;
}
static void mlx5_fc_stats_insert(struct mlx5_core_dev *dev,
struct mlx5_fc *counter)
{
struct list_head *next = mlx5_fc_counters_lookup_next(dev, counter->id);
list_add_tail(&counter->list, next);
}
static void mlx5_fc_stats_remove(struct mlx5_core_dev *dev,
struct mlx5_fc *counter)
{
struct mlx5_fc_stats *fc_stats = &dev->priv.fc_stats;
list_del(&counter->list);
spin_lock(&fc_stats->counters_idr_lock);
WARN_ON(!idr_remove(&fc_stats->counters_idr, counter->id));
spin_unlock(&fc_stats->counters_idr_lock);
}
/* The function returns the last counter that was queried so the caller
* function can continue calling it till all counters are queried.
*/
static struct mlx5_fc *mlx5_fc_stats_query(struct mlx5_core_dev *dev,
struct mlx5_fc *first,
u32 last_id)
{
struct mlx5_fc_stats *fc_stats = &dev->priv.fc_stats;
struct mlx5_fc *counter = NULL;
struct mlx5_cmd_fc_bulk *b;
bool more = false;
u32 afirst_id;
int num;
int err;
int max_bulk = min_t(int, MLX5_SW_MAX_COUNTERS_BULK,
(1 << MLX5_CAP_GEN(dev, log_max_flow_counter_bulk)));
/* first id must be aligned to 4 when using bulk query */
afirst_id = first->id & ~0x3;
/* number of counters to query inc. the last counter */
num = ALIGN(last_id - afirst_id + 1, 4);
if (num > max_bulk) {
num = max_bulk;
last_id = afirst_id + num - 1;
}
b = mlx5_cmd_fc_bulk_alloc(dev, afirst_id, num);
if (!b) {
mlx5_core_err(dev, "Error allocating resources for bulk query\n");
return NULL;
}
err = mlx5_cmd_fc_bulk_query(dev, b);
if (err) {
mlx5_core_err(dev, "Error doing bulk query: %d\n", err);
goto out;
}
counter = first;
list_for_each_entry_from(counter, &fc_stats->counters, list) {
struct mlx5_fc_cache *c = &counter->cache;
u64 packets;
u64 bytes;
if (counter->id > last_id) {
more = true;
break;
}
mlx5_cmd_fc_bulk_get(dev, b,
counter->id, &packets, &bytes);
if (c->packets == packets)
continue;
c->packets = packets;
c->bytes = bytes;
c->lastuse = jiffies;
}
out:
mlx5_cmd_fc_bulk_free(b);
return more ? counter : NULL;
}
static void mlx5_free_fc(struct mlx5_core_dev *dev,
struct mlx5_fc *counter)
{
mlx5_cmd_fc_free(dev, counter->id);
kfree(counter);
}
static void mlx5_fc_stats_work(struct work_struct *work)
{
struct mlx5_core_dev *dev = container_of(work, struct mlx5_core_dev,
priv.fc_stats.work.work);
struct mlx5_fc_stats *fc_stats = &dev->priv.fc_stats;
/* Take dellist first to ensure that counters cannot be deleted before
* they are inserted.
*/
struct llist_node *dellist = llist_del_all(&fc_stats->dellist);
struct llist_node *addlist = llist_del_all(&fc_stats->addlist);
struct mlx5_fc *counter = NULL, *last = NULL, *tmp;
unsigned long now = jiffies;
if (addlist || !list_empty(&fc_stats->counters))
queue_delayed_work(fc_stats->wq, &fc_stats->work,
fc_stats->sampling_interval);
llist_for_each_entry(counter, addlist, addlist)
mlx5_fc_stats_insert(dev, counter);
llist_for_each_entry_safe(counter, tmp, dellist, dellist) {
mlx5_fc_stats_remove(dev, counter);
mlx5_free_fc(dev, counter);
}
if (time_before(now, fc_stats->next_query) ||
list_empty(&fc_stats->counters))
return;
last = list_last_entry(&fc_stats->counters, struct mlx5_fc, list);
counter = list_first_entry(&fc_stats->counters, struct mlx5_fc,
list);
while (counter)
counter = mlx5_fc_stats_query(dev, counter, last->id);
fc_stats->next_query = now + fc_stats->sampling_interval;
}
struct mlx5_fc *mlx5_fc_create(struct mlx5_core_dev *dev, bool aging)
{
struct mlx5_fc_stats *fc_stats = &dev->priv.fc_stats;
struct mlx5_fc *counter;
int err;
counter = kzalloc(sizeof(*counter), GFP_KERNEL);
if (!counter)
return ERR_PTR(-ENOMEM);
INIT_LIST_HEAD(&counter->list);
err = mlx5_cmd_fc_alloc(dev, &counter->id);
if (err)
goto err_out;
if (aging) {
u32 id = counter->id;
counter->cache.lastuse = jiffies;
counter->aging = true;
idr_preload(GFP_KERNEL);
spin_lock(&fc_stats->counters_idr_lock);
err = idr_alloc_u32(&fc_stats->counters_idr, counter, &id, id,
GFP_NOWAIT);
spin_unlock(&fc_stats->counters_idr_lock);
idr_preload_end();
if (err)
goto err_out_alloc;
llist_add(&counter->addlist, &fc_stats->addlist);
mod_delayed_work(fc_stats->wq, &fc_stats->work, 0);
}
return counter;
err_out_alloc:
mlx5_cmd_fc_free(dev, counter->id);
err_out:
kfree(counter);
return ERR_PTR(err);
}
EXPORT_SYMBOL(mlx5_fc_create);
u32 mlx5_fc_id(struct mlx5_fc *counter)
{
return counter->id;
}
EXPORT_SYMBOL(mlx5_fc_id);
void mlx5_fc_destroy(struct mlx5_core_dev *dev, struct mlx5_fc *counter)
{
struct mlx5_fc_stats *fc_stats = &dev->priv.fc_stats;
if (!counter)
return;
if (counter->aging) {
llist_add(&counter->dellist, &fc_stats->dellist);
mod_delayed_work(fc_stats->wq, &fc_stats->work, 0);
return;
}
mlx5_free_fc(dev, counter);
}
EXPORT_SYMBOL(mlx5_fc_destroy);
int mlx5_init_fc_stats(struct mlx5_core_dev *dev)
{
struct mlx5_fc_stats *fc_stats = &dev->priv.fc_stats;
spin_lock_init(&fc_stats->counters_idr_lock);
idr_init(&fc_stats->counters_idr);
INIT_LIST_HEAD(&fc_stats->counters);
init_llist_head(&fc_stats->addlist);
init_llist_head(&fc_stats->dellist);
fc_stats->wq = create_singlethread_workqueue("mlx5_fc");
if (!fc_stats->wq)
return -ENOMEM;
fc_stats->sampling_interval = MLX5_FC_STATS_PERIOD;
INIT_DELAYED_WORK(&fc_stats->work, mlx5_fc_stats_work);
return 0;
}
void mlx5_cleanup_fc_stats(struct mlx5_core_dev *dev)
{
struct mlx5_fc_stats *fc_stats = &dev->priv.fc_stats;
struct llist_node *tmplist;
struct mlx5_fc *counter;
struct mlx5_fc *tmp;
cancel_delayed_work_sync(&dev->priv.fc_stats.work);
destroy_workqueue(dev->priv.fc_stats.wq);
dev->priv.fc_stats.wq = NULL;
idr_destroy(&fc_stats->counters_idr);
tmplist = llist_del_all(&fc_stats->addlist);
llist_for_each_entry_safe(counter, tmp, tmplist, addlist)
mlx5_free_fc(dev, counter);
list_for_each_entry_safe(counter, tmp, &fc_stats->counters, list)
mlx5_free_fc(dev, counter);
}
int mlx5_fc_query(struct mlx5_core_dev *dev, struct mlx5_fc *counter,
u64 *packets, u64 *bytes)
{
return mlx5_cmd_fc_query(dev, counter->id, packets, bytes);
}
EXPORT_SYMBOL(mlx5_fc_query);
u64 mlx5_fc_query_lastuse(struct mlx5_fc *counter)
{
return counter->cache.lastuse;
}
void mlx5_fc_query_cached(struct mlx5_fc *counter,
u64 *bytes, u64 *packets, u64 *lastuse)
{
struct mlx5_fc_cache c;
c = counter->cache;
*bytes = c.bytes - counter->lastbytes;
*packets = c.packets - counter->lastpackets;
*lastuse = c.lastuse;
counter->lastbytes = c.bytes;
counter->lastpackets = c.packets;
}
void mlx5_fc_queue_stats_work(struct mlx5_core_dev *dev,
struct delayed_work *dwork,
unsigned long delay)
{
struct mlx5_fc_stats *fc_stats = &dev->priv.fc_stats;
queue_delayed_work(fc_stats->wq, dwork, delay);
}
void mlx5_fc_update_sampling_interval(struct mlx5_core_dev *dev,
unsigned long interval)
{
struct mlx5_fc_stats *fc_stats = &dev->priv.fc_stats;
fc_stats->sampling_interval = min_t(unsigned long, interval,
fc_stats->sampling_interval);
}
