net/mlx5: Split irq_pool_affinity logic to new file

The downstream patches add more functionality to irq_pool_affinity.
Move the irq_pool_affinity logic to a new file in order to ease the
coding and maintenance of it.

Signed-off-by: Shay Drory <shayd@nvidia.com>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
This commit is contained in:
Shay Drory 2021-11-23 10:48:07 +02:00 committed by Saeed Mahameed
parent 30c6afa735
commit 424544df97
5 changed files with 157 additions and 97 deletions

View file

@ -109,7 +109,7 @@ mlx5_core-$(CONFIG_MLX5_SW_STEERING) += steering/dr_domain.o steering/dr_table.o
#
# SF device
#
mlx5_core-$(CONFIG_MLX5_SF) += sf/vhca_event.o sf/dev/dev.o sf/dev/driver.o
mlx5_core-$(CONFIG_MLX5_SF) += sf/vhca_event.o sf/dev/dev.o sf/dev/driver.o irq_affinity.o
#
# SF manager

View file

@ -0,0 +1,99 @@
// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
/* Copyright (c) 2021, NVIDIA CORPORATION & AFFILIATES. All rights reserved. */
#include "mlx5_core.h"
#include "mlx5_irq.h"
#include "pci_irq.h"
/* Creating an IRQ from irq_pool */
static struct mlx5_irq *
irq_pool_request_irq(struct mlx5_irq_pool *pool, const struct cpumask *req_mask)
{
u32 irq_index;
int err;
err = xa_alloc(&pool->irqs, &irq_index, NULL, pool->xa_num_irqs,
GFP_KERNEL);
if (err)
return ERR_PTR(err);
return mlx5_irq_alloc(pool, irq_index, req_mask);
}
/* Looking for the IRQ with the smallest refcount and the same mask */
static struct mlx5_irq *
irq_pool_find_least_loaded(struct mlx5_irq_pool *pool, const struct cpumask *req_mask)
{
int start = pool->xa_num_irqs.min;
int end = pool->xa_num_irqs.max;
struct mlx5_irq *irq = NULL;
struct mlx5_irq *iter;
int irq_refcount = 0;
unsigned long index;
lockdep_assert_held(&pool->lock);
xa_for_each_range(&pool->irqs, index, iter, start, end) {
struct cpumask *iter_mask = mlx5_irq_get_affinity_mask(iter);
int iter_refcount = mlx5_irq_read_locked(iter);
if (!cpumask_equal(iter_mask, req_mask))
/* If a user request a mask, skip IRQs that's aren't a match */
continue;
if (iter_refcount < pool->min_threshold)
/* If we found an IRQ with less than min_thres, return it */
return iter;
if (!irq || iter_refcount < irq_refcount) {
/* In case we won't find an IRQ with less than min_thres,
* keep a pointer to the least used IRQ
*/
irq_refcount = iter_refcount;
irq = iter;
}
}
return irq;
}
/**
* mlx5_irq_affinity_request - request an IRQ according to the given mask.
* @pool: IRQ pool to request from.
* @req_mask: cpumask requested for this IRQ.
*
* This function returns a pointer to IRQ, or ERR_PTR in case of error.
*/
struct mlx5_irq *
mlx5_irq_affinity_request(struct mlx5_irq_pool *pool, const struct cpumask *req_mask)
{
struct mlx5_irq *least_loaded_irq, *new_irq;
mutex_lock(&pool->lock);
least_loaded_irq = irq_pool_find_least_loaded(pool, req_mask);
if (least_loaded_irq &&
mlx5_irq_read_locked(least_loaded_irq) < pool->min_threshold)
goto out;
/* We didn't find an IRQ with less than min_thres, try to allocate a new IRQ */
new_irq = irq_pool_request_irq(pool, req_mask);
if (IS_ERR(new_irq)) {
if (!least_loaded_irq) {
/* We failed to create an IRQ and we didn't find an IRQ */
mlx5_core_err(pool->dev, "Didn't find a matching IRQ. err = %ld\n",
PTR_ERR(new_irq));
mutex_unlock(&pool->lock);
return new_irq;
}
/* We failed to create a new IRQ for the requested affinity,
* sharing existing IRQ.
*/
goto out;
}
least_loaded_irq = new_irq;
goto unlock;
out:
mlx5_irq_get_locked(least_loaded_irq);
if (mlx5_irq_read_locked(least_loaded_irq) > pool->max_threshold)
mlx5_core_dbg(pool->dev, "IRQ %u overloaded, pool_name: %s, %u EQs on this irq\n",
pci_irq_vector(pool->dev->pdev,
mlx5_irq_get_index(least_loaded_irq)), pool->name,
mlx5_irq_read_locked(least_loaded_irq) / MLX5_EQ_REFS_PER_IRQ);
unlock:
mutex_unlock(&pool->lock);
return least_loaded_irq;
}

View file

@ -31,4 +31,15 @@ int mlx5_irq_detach_nb(struct mlx5_irq *irq, struct notifier_block *nb);
struct cpumask *mlx5_irq_get_affinity_mask(struct mlx5_irq *irq);
int mlx5_irq_get_index(struct mlx5_irq *irq);
struct mlx5_irq_pool;
#ifdef CONFIG_MLX5_SF
struct mlx5_irq *mlx5_irq_affinity_request(struct mlx5_irq_pool *pool,
const struct cpumask *req_mask);
#else
static inline struct mlx5_irq *
mlx5_irq_affinity_request(struct mlx5_irq_pool *pool, const struct cpumask *req_mask)
{
return ERR_PTR(-EOPNOTSUPP);
}
#endif
#endif /* __MLX5_IRQ_H__ */

View file

@ -7,15 +7,12 @@
#include <linux/mlx5/driver.h>
#include "mlx5_core.h"
#include "mlx5_irq.h"
#include "pci_irq.h"
#include "lib/sf.h"
#ifdef CONFIG_RFS_ACCEL
#include <linux/cpu_rmap.h>
#endif
#define MLX5_MAX_IRQ_NAME (32)
/* max irq_index is 2047, so four chars */
#define MLX5_MAX_IRQ_IDX_CHARS (4)
#define MLX5_SFS_PER_CTRL_IRQ 64
#define MLX5_IRQ_CTRL_SF_MAX 8
/* min num of vectors for SFs to be enabled */
@ -25,7 +22,6 @@
#define MLX5_EQ_SHARE_IRQ_MAX_CTRL (UINT_MAX)
#define MLX5_EQ_SHARE_IRQ_MIN_COMP (1)
#define MLX5_EQ_SHARE_IRQ_MIN_CTRL (4)
#define MLX5_EQ_REFS_PER_IRQ (2)
struct mlx5_irq {
struct atomic_notifier_head nh;
@ -37,16 +33,6 @@ struct mlx5_irq {
int irqn;
};
struct mlx5_irq_pool {
char name[MLX5_MAX_IRQ_NAME - MLX5_MAX_IRQ_IDX_CHARS];
struct xa_limit xa_num_irqs;
struct mutex lock; /* sync IRQs creations */
struct xarray irqs;
u32 max_threshold;
u32 min_threshold;
struct mlx5_core_dev *dev;
};
struct mlx5_irq_table {
struct mlx5_irq_pool *pf_pool;
struct mlx5_irq_pool *sf_ctrl_pool;
@ -164,7 +150,13 @@ static void irq_put(struct mlx5_irq *irq)
mutex_unlock(&pool->lock);
}
static int irq_get_locked(struct mlx5_irq *irq)
int mlx5_irq_read_locked(struct mlx5_irq *irq)
{
lockdep_assert_held(&irq->pool->lock);
return irq->refcount;
}
int mlx5_irq_get_locked(struct mlx5_irq *irq)
{
lockdep_assert_held(&irq->pool->lock);
if (WARN_ON_ONCE(!irq->refcount))
@ -178,7 +170,7 @@ static int irq_get(struct mlx5_irq *irq)
int err;
mutex_lock(&irq->pool->lock);
err = irq_get_locked(irq);
err = mlx5_irq_get_locked(irq);
mutex_unlock(&irq->pool->lock);
return err;
}
@ -215,8 +207,8 @@ static bool irq_pool_is_sf_pool(struct mlx5_irq_pool *pool)
return !strncmp("mlx5_sf", pool->name, strlen("mlx5_sf"));
}
static struct mlx5_irq *irq_request(struct mlx5_irq_pool *pool, int i,
struct cpumask *affinity)
struct mlx5_irq *mlx5_irq_alloc(struct mlx5_irq_pool *pool, int i,
const struct cpumask *affinity)
{
struct mlx5_core_dev *dev = pool->dev;
char name[MLX5_MAX_IRQ_NAME];
@ -306,79 +298,6 @@ int mlx5_irq_get_index(struct mlx5_irq *irq)
/* irq_pool API */
/* creating an irq from irq_pool */
static struct mlx5_irq *irq_pool_create_irq(struct mlx5_irq_pool *pool,
struct cpumask *affinity)
{
u32 irq_index;
int err;
err = xa_alloc(&pool->irqs, &irq_index, NULL, pool->xa_num_irqs,
GFP_KERNEL);
if (err)
return ERR_PTR(err);
return irq_request(pool, irq_index, affinity);
}
/* looking for the irq with the smallest refcount and the same affinity */
static struct mlx5_irq *irq_pool_find_least_loaded(struct mlx5_irq_pool *pool,
struct cpumask *affinity)
{
int start = pool->xa_num_irqs.min;
int end = pool->xa_num_irqs.max;
struct mlx5_irq *irq = NULL;
struct mlx5_irq *iter;
unsigned long index;
lockdep_assert_held(&pool->lock);
xa_for_each_range(&pool->irqs, index, iter, start, end) {
if (!cpumask_equal(iter->mask, affinity))
continue;
if (iter->refcount < pool->min_threshold)
return iter;
if (!irq || iter->refcount < irq->refcount)
irq = iter;
}
return irq;
}
/* requesting an irq from a given pool according to given affinity */
static struct mlx5_irq *irq_pool_request_affinity(struct mlx5_irq_pool *pool,
struct cpumask *affinity)
{
struct mlx5_irq *least_loaded_irq, *new_irq;
mutex_lock(&pool->lock);
least_loaded_irq = irq_pool_find_least_loaded(pool, affinity);
if (least_loaded_irq &&
least_loaded_irq->refcount < pool->min_threshold)
goto out;
new_irq = irq_pool_create_irq(pool, affinity);
if (IS_ERR(new_irq)) {
if (!least_loaded_irq) {
mlx5_core_err(pool->dev, "Didn't find a matching IRQ. err = %ld\n",
PTR_ERR(new_irq));
mutex_unlock(&pool->lock);
return new_irq;
}
/* We failed to create a new IRQ for the requested affinity,
* sharing existing IRQ.
*/
goto out;
}
least_loaded_irq = new_irq;
goto unlock;
out:
irq_get_locked(least_loaded_irq);
if (least_loaded_irq->refcount > pool->max_threshold)
mlx5_core_dbg(pool->dev, "IRQ %u overloaded, pool_name: %s, %u EQs on this irq\n",
least_loaded_irq->irqn, pool->name,
least_loaded_irq->refcount / MLX5_EQ_REFS_PER_IRQ);
unlock:
mutex_unlock(&pool->lock);
return least_loaded_irq;
}
/* requesting an irq from a given pool according to given index */
static struct mlx5_irq *
irq_pool_request_vector(struct mlx5_irq_pool *pool, int vecidx,
@ -389,10 +308,10 @@ irq_pool_request_vector(struct mlx5_irq_pool *pool, int vecidx,
mutex_lock(&pool->lock);
irq = xa_load(&pool->irqs, vecidx);
if (irq) {
irq_get_locked(irq);
mlx5_irq_get_locked(irq);
goto unlock;
}
irq = irq_request(pool, vecidx, affinity);
irq = mlx5_irq_alloc(pool, vecidx, affinity);
unlock:
mutex_unlock(&pool->lock);
return irq;
@ -457,7 +376,7 @@ struct mlx5_irq *mlx5_ctrl_irq_request(struct mlx5_core_dev *dev)
/* Allocate the IRQ in the last index of the pool */
irq = irq_pool_request_vector(pool, pool->xa_num_irqs.max, req_mask);
} else {
irq = irq_pool_request_affinity(pool, req_mask);
irq = mlx5_irq_affinity_request(pool, req_mask);
}
free_cpumask_var(req_mask);
@ -489,7 +408,7 @@ struct mlx5_irq *mlx5_irq_request(struct mlx5_core_dev *dev, u16 vecidx,
/* In case an SF user request IRQ with vecidx */
irq = irq_pool_request_vector(pool, vecidx, NULL);
else
irq = irq_pool_request_affinity(pool, affinity);
irq = mlx5_irq_affinity_request(pool, affinity);
goto out;
}
pf_irq:

View file

@ -0,0 +1,31 @@
/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
/* Copyright (c) 2021, NVIDIA CORPORATION & AFFILIATES. All rights reserved. */
#ifndef __PCI_IRQ_H__
#define __PCI_IRQ_H__
#include <linux/mlx5/driver.h>
#define MLX5_MAX_IRQ_NAME (32)
/* max irq_index is 2047, so four chars */
#define MLX5_MAX_IRQ_IDX_CHARS (4)
#define MLX5_EQ_REFS_PER_IRQ (2)
struct mlx5_irq;
struct mlx5_irq_pool {
char name[MLX5_MAX_IRQ_NAME - MLX5_MAX_IRQ_IDX_CHARS];
struct xa_limit xa_num_irqs;
struct mutex lock; /* sync IRQs creations */
struct xarray irqs;
u32 max_threshold;
u32 min_threshold;
struct mlx5_core_dev *dev;
};
struct mlx5_irq *mlx5_irq_alloc(struct mlx5_irq_pool *pool, int i,
const struct cpumask *affinity);
int mlx5_irq_get_locked(struct mlx5_irq *irq);
int mlx5_irq_read_locked(struct mlx5_irq *irq);
#endif /* __PCI_IRQ_H__ */