Quelle  spectrum_cnt.c   Sprache: C

// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/* Copyright (c) 2017-2018 Mellanox Technologies. All rights reserved */

#include <linux/kernel.h>
#include <linux/bitops.h>
#include <linux/spinlock.h>

#include "spectrum_cnt.h"

struct mlxsw_sp_counter_sub_pool {
 u64 size;
 unsigned int base_index;
 enum mlxsw_res_id entry_size_res_id;
 const char *resource_name; /* devlink resource name */
 u64 resource_id; /* devlink resource id */
 unsigned int entry_size;
 unsigned int bank_count;
 atomic_t active_entries_count;
};

struct mlxsw_sp_counter_pool {
 u64 pool_size;
 unsigned long *usage; /* Usage bitmap */
 spinlock_t counter_pool_lock; /* Protects counter pool allocations */
 atomic_t active_entries_count;
 unsigned int sub_pools_count;
 struct mlxsw_sp_counter_sub_pool sub_pools[] __counted_by(sub_pools_count);
};

static const struct mlxsw_sp_counter_sub_pool mlxsw_sp_counter_sub_pools[] = {
 [MLXSW_SP_COUNTER_SUB_POOL_FLOW] = {
  .entry_size_res_id = MLXSW_RES_ID_COUNTER_SIZE_PACKETS_BYTES,
  .resource_name = MLXSW_SP_RESOURCE_NAME_COUNTERS_FLOW,
  .resource_id = MLXSW_SP_RESOURCE_COUNTERS_FLOW,
  .bank_count = 6,
 },
 [MLXSW_SP_COUNTER_SUB_POOL_RIF] = {
  .entry_size_res_id = MLXSW_RES_ID_COUNTER_SIZE_ROUTER_BASIC,
  .resource_name = MLXSW_SP_RESOURCE_NAME_COUNTERS_RIF,
  .resource_id = MLXSW_SP_RESOURCE_COUNTERS_RIF,
  .bank_count = 2,
 }
};

static u64 mlxsw_sp_counter_sub_pool_occ_get(void *priv)
{
 const struct mlxsw_sp_counter_sub_pool *sub_pool = priv;

 return atomic_read(&sub_pool->active_entries_count);
}

static int mlxsw_sp_counter_sub_pools_init(struct mlxsw_sp *mlxsw_sp)
{
 struct mlxsw_sp_counter_pool *pool = mlxsw_sp->counter_pool;
 struct devlink *devlink = priv_to_devlink(mlxsw_sp->core);
 struct mlxsw_sp_counter_sub_pool *sub_pool;
 unsigned int base_index = 0;
 enum mlxsw_res_id res_id;
 int err;
 int i;

 for (i = 0; i < pool->sub_pools_count; i++) {
  sub_pool = &pool->sub_pools[i];
  res_id = sub_pool->entry_size_res_id;

  if (!mlxsw_core_res_valid(mlxsw_sp->core, res_id))
   return -EIO;
  sub_pool->entry_size = mlxsw_core_res_get(mlxsw_sp->core,
         res_id);
  err = devl_resource_size_get(devlink,
          sub_pool->resource_id,
          &sub_pool->size);
  if (err)
   goto err_resource_size_get;

  devl_resource_occ_get_register(devlink,
            sub_pool->resource_id,
            mlxsw_sp_counter_sub_pool_occ_get,
            sub_pool);

  sub_pool->base_index = base_index;
  base_index += sub_pool->size;
  atomic_set(&sub_pool->active_entries_count, 0);
 }
 return 0;

err_resource_size_get:
 for (i--; i >= 0; i--) {
  sub_pool = &pool->sub_pools[i];

  devl_resource_occ_get_unregister(devlink,
       sub_pool->resource_id);
 }
 return err;
}

static void mlxsw_sp_counter_sub_pools_fini(struct mlxsw_sp *mlxsw_sp)
{
 struct mlxsw_sp_counter_pool *pool = mlxsw_sp->counter_pool;
 struct devlink *devlink = priv_to_devlink(mlxsw_sp->core);
 struct mlxsw_sp_counter_sub_pool *sub_pool;
 int i;

 for (i = 0; i < pool->sub_pools_count; i++) {
  sub_pool = &pool->sub_pools[i];

  WARN_ON(atomic_read(&sub_pool->active_entries_count));
  devl_resource_occ_get_unregister(devlink,
       sub_pool->resource_id);
 }
}

static u64 mlxsw_sp_counter_pool_occ_get(void *priv)
{
 const struct mlxsw_sp_counter_pool *pool = priv;

 return atomic_read(&pool->active_entries_count);
}

int mlxsw_sp_counter_pool_init(struct mlxsw_sp *mlxsw_sp)
{
 unsigned int sub_pools_count = ARRAY_SIZE(mlxsw_sp_counter_sub_pools);
 struct devlink *devlink = priv_to_devlink(mlxsw_sp->core);
 struct mlxsw_sp_counter_pool *pool;
 int err;

 pool = kzalloc(struct_size(pool, sub_pools, sub_pools_count),
         GFP_KERNEL);
 if (!pool)
  return -ENOMEM;
 mlxsw_sp->counter_pool = pool;
 pool->sub_pools_count = sub_pools_count;
 memcpy(pool->sub_pools, mlxsw_sp_counter_sub_pools,
        flex_array_size(pool, sub_pools, pool->sub_pools_count));
 spin_lock_init(&pool->counter_pool_lock);
 atomic_set(&pool->active_entries_count, 0);

 err = devl_resource_size_get(devlink, MLXSW_SP_RESOURCE_COUNTERS,
         &pool->pool_size);
 if (err)
  goto err_pool_resource_size_get;
 devl_resource_occ_get_register(devlink, MLXSW_SP_RESOURCE_COUNTERS,
           mlxsw_sp_counter_pool_occ_get, pool);

 pool->usage = bitmap_zalloc(pool->pool_size, GFP_KERNEL);
 if (!pool->usage) {
  err = -ENOMEM;
  goto err_usage_alloc;
 }

 err = mlxsw_sp_counter_sub_pools_init(mlxsw_sp);
 if (err)
  goto err_sub_pools_init;

 return 0;

err_sub_pools_init:
 bitmap_free(pool->usage);
err_usage_alloc:
 devl_resource_occ_get_unregister(devlink,
      MLXSW_SP_RESOURCE_COUNTERS);
err_pool_resource_size_get:
 kfree(pool);
 return err;
}

void mlxsw_sp_counter_pool_fini(struct mlxsw_sp *mlxsw_sp)
{
 struct mlxsw_sp_counter_pool *pool = mlxsw_sp->counter_pool;
 struct devlink *devlink = priv_to_devlink(mlxsw_sp->core);

 mlxsw_sp_counter_sub_pools_fini(mlxsw_sp);
 WARN_ON(find_first_bit(pool->usage, pool->pool_size) !=
          pool->pool_size);
 WARN_ON(atomic_read(&pool->active_entries_count));
 bitmap_free(pool->usage);
 devl_resource_occ_get_unregister(devlink,
      MLXSW_SP_RESOURCE_COUNTERS);
 kfree(pool);
}

int mlxsw_sp_counter_alloc(struct mlxsw_sp *mlxsw_sp,
      enum mlxsw_sp_counter_sub_pool_id sub_pool_id,
      unsigned int *p_counter_index)
{
 struct mlxsw_sp_counter_pool *pool = mlxsw_sp->counter_pool;
 struct mlxsw_sp_counter_sub_pool *sub_pool;
 unsigned int entry_index;
 unsigned int stop_index;
 int i, err;

 sub_pool = &pool->sub_pools[sub_pool_id];
 stop_index = sub_pool->base_index + sub_pool->size;
 entry_index = sub_pool->base_index;

 spin_lock(&pool->counter_pool_lock);
 entry_index = find_next_zero_bit(pool->usage, stop_index, entry_index);
 if (entry_index == stop_index) {
  err = -ENOBUFS;
  goto err_alloc;
 }
 /* The sub-pools can contain non-integer number of entries
 * so we must check for overflow
 */
 if (entry_index + sub_pool->entry_size > stop_index) {
  err = -ENOBUFS;
  goto err_alloc;
 }
 for (i = 0; i < sub_pool->entry_size; i++)
  __set_bit(entry_index + i, pool->usage);
 spin_unlock(&pool->counter_pool_lock);

 *p_counter_index = entry_index;
 atomic_add(sub_pool->entry_size, &sub_pool->active_entries_count);
 atomic_add(sub_pool->entry_size, &pool->active_entries_count);
 return 0;

err_alloc:
 spin_unlock(&pool->counter_pool_lock);
 return err;
}

void mlxsw_sp_counter_free(struct mlxsw_sp *mlxsw_sp,
      enum mlxsw_sp_counter_sub_pool_id sub_pool_id,
      unsigned int counter_index)
{
 struct mlxsw_sp_counter_pool *pool = mlxsw_sp->counter_pool;
 struct mlxsw_sp_counter_sub_pool *sub_pool;
 int i;

 if (WARN_ON(counter_index >= pool->pool_size))
  return;
 sub_pool = &pool->sub_pools[sub_pool_id];
 spin_lock(&pool->counter_pool_lock);
 for (i = 0; i < sub_pool->entry_size; i++)
  __clear_bit(counter_index + i, pool->usage);
 spin_unlock(&pool->counter_pool_lock);
 atomic_sub(sub_pool->entry_size, &sub_pool->active_entries_count);
 atomic_sub(sub_pool->entry_size, &pool->active_entries_count);
}

int mlxsw_sp_counter_resources_register(struct mlxsw_core *mlxsw_core)
{
 static struct devlink_resource_size_params size_params;
 struct devlink *devlink = priv_to_devlink(mlxsw_core);
 const struct mlxsw_sp_counter_sub_pool *sub_pool;
 unsigned int total_bank_config;
 u64 sub_pool_size;
 u64 base_index;
 u64 pool_size;
 u64 bank_size;
 int err;
 int i;

 if (!MLXSW_CORE_RES_VALID(mlxsw_core, COUNTER_POOL_SIZE) ||
     !MLXSW_CORE_RES_VALID(mlxsw_core, COUNTER_BANK_SIZE))
  return -EIO;

 pool_size = MLXSW_CORE_RES_GET(mlxsw_core, COUNTER_POOL_SIZE);
 bank_size = MLXSW_CORE_RES_GET(mlxsw_core, COUNTER_BANK_SIZE);

 devlink_resource_size_params_init(&size_params, pool_size,
       pool_size, bank_size,
       DEVLINK_RESOURCE_UNIT_ENTRY);
 err = devl_resource_register(devlink,
         MLXSW_SP_RESOURCE_NAME_COUNTERS,
         pool_size,
         MLXSW_SP_RESOURCE_COUNTERS,
         DEVLINK_RESOURCE_ID_PARENT_TOP,
         &size_params);
 if (err)
  return err;

 /* Allocation is based on bank count which should be
 * specified for each sub pool statically.
 */
 total_bank_config = 0;
 base_index = 0;
 for (i = 0; i < ARRAY_SIZE(mlxsw_sp_counter_sub_pools); i++) {
  sub_pool = &mlxsw_sp_counter_sub_pools[i];
  sub_pool_size = sub_pool->bank_count * bank_size;
  /* The last bank can't be fully used */
  if (base_index + sub_pool_size > pool_size)
   sub_pool_size = pool_size - base_index;
  base_index += sub_pool_size;

  devlink_resource_size_params_init(&size_params, sub_pool_size,
        sub_pool_size, bank_size,
        DEVLINK_RESOURCE_UNIT_ENTRY);
  err = devl_resource_register(devlink,
          sub_pool->resource_name,
          sub_pool_size,
          sub_pool->resource_id,
          MLXSW_SP_RESOURCE_COUNTERS,
          &size_params);
  if (err)
   return err;
  total_bank_config += sub_pool->bank_count;
 }

 /* Check config is valid, no bank over subscription */
 if (WARN_ON(total_bank_config > div64_u64(pool_size, bank_size) + 1))
  return -EINVAL;

 return 0;
}