mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-10-30 08:02:30 +00:00
1751cc365f
The moved code deals with managing rx buffers and queues. A tiny bit of refactoring was required in other files to stitch the code together. Signed-off-by: Alexandru-Mihai Maftei <amaftei@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
375 lines
11 KiB
C
375 lines
11 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/****************************************************************************
|
|
* Driver for Solarflare network controllers and boards
|
|
* Copyright 2018 Solarflare Communications Inc.
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify it
|
|
* under the terms of the GNU General Public License version 2 as published
|
|
* by the Free Software Foundation, incorporated herein by reference.
|
|
*/
|
|
|
|
#include "net_driver.h"
|
|
#include <linux/module.h>
|
|
#include "efx.h"
|
|
#include "nic.h"
|
|
#include "rx_common.h"
|
|
|
|
/* This is the percentage fill level below which new RX descriptors
|
|
* will be added to the RX descriptor ring.
|
|
*/
|
|
static unsigned int rx_refill_threshold;
|
|
module_param(rx_refill_threshold, uint, 0444);
|
|
MODULE_PARM_DESC(rx_refill_threshold,
|
|
"RX descriptor ring refill threshold (%)");
|
|
|
|
/* RX maximum head room required.
|
|
*
|
|
* This must be at least 1 to prevent overflow, plus one packet-worth
|
|
* to allow pipelined receives.
|
|
*/
|
|
#define EFX_RXD_HEAD_ROOM (1 + EFX_RX_MAX_FRAGS)
|
|
|
|
static void efx_fini_rx_buffer(struct efx_rx_queue *rx_queue,
|
|
struct efx_rx_buffer *rx_buf)
|
|
{
|
|
/* Release the page reference we hold for the buffer. */
|
|
if (rx_buf->page)
|
|
put_page(rx_buf->page);
|
|
|
|
/* If this is the last buffer in a page, unmap and free it. */
|
|
if (rx_buf->flags & EFX_RX_BUF_LAST_IN_PAGE) {
|
|
efx_unmap_rx_buffer(rx_queue->efx, rx_buf);
|
|
efx_free_rx_buffers(rx_queue, rx_buf, 1);
|
|
}
|
|
rx_buf->page = NULL;
|
|
}
|
|
|
|
int efx_probe_rx_queue(struct efx_rx_queue *rx_queue)
|
|
{
|
|
struct efx_nic *efx = rx_queue->efx;
|
|
unsigned int entries;
|
|
int rc;
|
|
|
|
/* Create the smallest power-of-two aligned ring */
|
|
entries = max(roundup_pow_of_two(efx->rxq_entries), EFX_MIN_DMAQ_SIZE);
|
|
EFX_WARN_ON_PARANOID(entries > EFX_MAX_DMAQ_SIZE);
|
|
rx_queue->ptr_mask = entries - 1;
|
|
|
|
netif_dbg(efx, probe, efx->net_dev,
|
|
"creating RX queue %d size %#x mask %#x\n",
|
|
efx_rx_queue_index(rx_queue), efx->rxq_entries,
|
|
rx_queue->ptr_mask);
|
|
|
|
/* Allocate RX buffers */
|
|
rx_queue->buffer = kcalloc(entries, sizeof(*rx_queue->buffer),
|
|
GFP_KERNEL);
|
|
if (!rx_queue->buffer)
|
|
return -ENOMEM;
|
|
|
|
rc = efx_nic_probe_rx(rx_queue);
|
|
if (rc) {
|
|
kfree(rx_queue->buffer);
|
|
rx_queue->buffer = NULL;
|
|
}
|
|
|
|
return rc;
|
|
}
|
|
|
|
void efx_init_rx_queue(struct efx_rx_queue *rx_queue)
|
|
{
|
|
unsigned int max_fill, trigger, max_trigger;
|
|
struct efx_nic *efx = rx_queue->efx;
|
|
int rc = 0;
|
|
|
|
netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
|
|
"initialising RX queue %d\n", efx_rx_queue_index(rx_queue));
|
|
|
|
/* Initialise ptr fields */
|
|
rx_queue->added_count = 0;
|
|
rx_queue->notified_count = 0;
|
|
rx_queue->removed_count = 0;
|
|
rx_queue->min_fill = -1U;
|
|
efx_init_rx_recycle_ring(rx_queue);
|
|
|
|
rx_queue->page_remove = 0;
|
|
rx_queue->page_add = rx_queue->page_ptr_mask + 1;
|
|
rx_queue->page_recycle_count = 0;
|
|
rx_queue->page_recycle_failed = 0;
|
|
rx_queue->page_recycle_full = 0;
|
|
|
|
/* Initialise limit fields */
|
|
max_fill = efx->rxq_entries - EFX_RXD_HEAD_ROOM;
|
|
max_trigger =
|
|
max_fill - efx->rx_pages_per_batch * efx->rx_bufs_per_page;
|
|
if (rx_refill_threshold != 0) {
|
|
trigger = max_fill * min(rx_refill_threshold, 100U) / 100U;
|
|
if (trigger > max_trigger)
|
|
trigger = max_trigger;
|
|
} else {
|
|
trigger = max_trigger;
|
|
}
|
|
|
|
rx_queue->max_fill = max_fill;
|
|
rx_queue->fast_fill_trigger = trigger;
|
|
rx_queue->refill_enabled = true;
|
|
|
|
/* Initialise XDP queue information */
|
|
rc = xdp_rxq_info_reg(&rx_queue->xdp_rxq_info, efx->net_dev,
|
|
rx_queue->core_index);
|
|
|
|
if (rc) {
|
|
netif_err(efx, rx_err, efx->net_dev,
|
|
"Failure to initialise XDP queue information rc=%d\n",
|
|
rc);
|
|
efx->xdp_rxq_info_failed = true;
|
|
} else {
|
|
rx_queue->xdp_rxq_info_valid = true;
|
|
}
|
|
|
|
/* Set up RX descriptor ring */
|
|
efx_nic_init_rx(rx_queue);
|
|
}
|
|
|
|
void efx_fini_rx_queue(struct efx_rx_queue *rx_queue)
|
|
{
|
|
struct efx_nic *efx = rx_queue->efx;
|
|
struct efx_rx_buffer *rx_buf;
|
|
int i;
|
|
|
|
netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
|
|
"shutting down RX queue %d\n", efx_rx_queue_index(rx_queue));
|
|
|
|
del_timer_sync(&rx_queue->slow_fill);
|
|
|
|
/* Release RX buffers from the current read ptr to the write ptr */
|
|
if (rx_queue->buffer) {
|
|
for (i = rx_queue->removed_count; i < rx_queue->added_count;
|
|
i++) {
|
|
unsigned int index = i & rx_queue->ptr_mask;
|
|
|
|
rx_buf = efx_rx_buffer(rx_queue, index);
|
|
efx_fini_rx_buffer(rx_queue, rx_buf);
|
|
}
|
|
}
|
|
|
|
/* Unmap and release the pages in the recycle ring. Remove the ring. */
|
|
for (i = 0; i <= rx_queue->page_ptr_mask; i++) {
|
|
struct page *page = rx_queue->page_ring[i];
|
|
struct efx_rx_page_state *state;
|
|
|
|
if (page == NULL)
|
|
continue;
|
|
|
|
state = page_address(page);
|
|
dma_unmap_page(&efx->pci_dev->dev, state->dma_addr,
|
|
PAGE_SIZE << efx->rx_buffer_order,
|
|
DMA_FROM_DEVICE);
|
|
put_page(page);
|
|
}
|
|
kfree(rx_queue->page_ring);
|
|
rx_queue->page_ring = NULL;
|
|
|
|
if (rx_queue->xdp_rxq_info_valid)
|
|
xdp_rxq_info_unreg(&rx_queue->xdp_rxq_info);
|
|
|
|
rx_queue->xdp_rxq_info_valid = false;
|
|
}
|
|
|
|
void efx_remove_rx_queue(struct efx_rx_queue *rx_queue)
|
|
{
|
|
netif_dbg(rx_queue->efx, drv, rx_queue->efx->net_dev,
|
|
"destroying RX queue %d\n", efx_rx_queue_index(rx_queue));
|
|
|
|
efx_nic_remove_rx(rx_queue);
|
|
|
|
kfree(rx_queue->buffer);
|
|
rx_queue->buffer = NULL;
|
|
}
|
|
|
|
/* Unmap a DMA-mapped page. This function is only called for the final RX
|
|
* buffer in a page.
|
|
*/
|
|
void efx_unmap_rx_buffer(struct efx_nic *efx,
|
|
struct efx_rx_buffer *rx_buf)
|
|
{
|
|
struct page *page = rx_buf->page;
|
|
|
|
if (page) {
|
|
struct efx_rx_page_state *state = page_address(page);
|
|
|
|
dma_unmap_page(&efx->pci_dev->dev,
|
|
state->dma_addr,
|
|
PAGE_SIZE << efx->rx_buffer_order,
|
|
DMA_FROM_DEVICE);
|
|
}
|
|
}
|
|
|
|
void efx_free_rx_buffers(struct efx_rx_queue *rx_queue,
|
|
struct efx_rx_buffer *rx_buf,
|
|
unsigned int num_bufs)
|
|
{
|
|
do {
|
|
if (rx_buf->page) {
|
|
put_page(rx_buf->page);
|
|
rx_buf->page = NULL;
|
|
}
|
|
rx_buf = efx_rx_buf_next(rx_queue, rx_buf);
|
|
} while (--num_bufs);
|
|
}
|
|
|
|
void efx_rx_slow_fill(struct timer_list *t)
|
|
{
|
|
struct efx_rx_queue *rx_queue = from_timer(rx_queue, t, slow_fill);
|
|
|
|
/* Post an event to cause NAPI to run and refill the queue */
|
|
efx_nic_generate_fill_event(rx_queue);
|
|
++rx_queue->slow_fill_count;
|
|
}
|
|
|
|
void efx_schedule_slow_fill(struct efx_rx_queue *rx_queue)
|
|
{
|
|
mod_timer(&rx_queue->slow_fill, jiffies + msecs_to_jiffies(10));
|
|
}
|
|
|
|
/* efx_init_rx_buffers - create EFX_RX_BATCH page-based RX buffers
|
|
*
|
|
* @rx_queue: Efx RX queue
|
|
*
|
|
* This allocates a batch of pages, maps them for DMA, and populates
|
|
* struct efx_rx_buffers for each one. Return a negative error code or
|
|
* 0 on success. If a single page can be used for multiple buffers,
|
|
* then the page will either be inserted fully, or not at all.
|
|
*/
|
|
static int efx_init_rx_buffers(struct efx_rx_queue *rx_queue, bool atomic)
|
|
{
|
|
unsigned int page_offset, index, count;
|
|
struct efx_nic *efx = rx_queue->efx;
|
|
struct efx_rx_page_state *state;
|
|
struct efx_rx_buffer *rx_buf;
|
|
dma_addr_t dma_addr;
|
|
struct page *page;
|
|
|
|
count = 0;
|
|
do {
|
|
page = efx_reuse_page(rx_queue);
|
|
if (page == NULL) {
|
|
page = alloc_pages(__GFP_COMP |
|
|
(atomic ? GFP_ATOMIC : GFP_KERNEL),
|
|
efx->rx_buffer_order);
|
|
if (unlikely(page == NULL))
|
|
return -ENOMEM;
|
|
dma_addr =
|
|
dma_map_page(&efx->pci_dev->dev, page, 0,
|
|
PAGE_SIZE << efx->rx_buffer_order,
|
|
DMA_FROM_DEVICE);
|
|
if (unlikely(dma_mapping_error(&efx->pci_dev->dev,
|
|
dma_addr))) {
|
|
__free_pages(page, efx->rx_buffer_order);
|
|
return -EIO;
|
|
}
|
|
state = page_address(page);
|
|
state->dma_addr = dma_addr;
|
|
} else {
|
|
state = page_address(page);
|
|
dma_addr = state->dma_addr;
|
|
}
|
|
|
|
dma_addr += sizeof(struct efx_rx_page_state);
|
|
page_offset = sizeof(struct efx_rx_page_state);
|
|
|
|
do {
|
|
index = rx_queue->added_count & rx_queue->ptr_mask;
|
|
rx_buf = efx_rx_buffer(rx_queue, index);
|
|
rx_buf->dma_addr = dma_addr + efx->rx_ip_align +
|
|
XDP_PACKET_HEADROOM;
|
|
rx_buf->page = page;
|
|
rx_buf->page_offset = page_offset + efx->rx_ip_align +
|
|
XDP_PACKET_HEADROOM;
|
|
rx_buf->len = efx->rx_dma_len;
|
|
rx_buf->flags = 0;
|
|
++rx_queue->added_count;
|
|
get_page(page);
|
|
dma_addr += efx->rx_page_buf_step;
|
|
page_offset += efx->rx_page_buf_step;
|
|
} while (page_offset + efx->rx_page_buf_step <= PAGE_SIZE);
|
|
|
|
rx_buf->flags = EFX_RX_BUF_LAST_IN_PAGE;
|
|
} while (++count < efx->rx_pages_per_batch);
|
|
|
|
return 0;
|
|
}
|
|
|
|
void efx_rx_config_page_split(struct efx_nic *efx)
|
|
{
|
|
efx->rx_page_buf_step = ALIGN(efx->rx_dma_len + efx->rx_ip_align +
|
|
XDP_PACKET_HEADROOM,
|
|
EFX_RX_BUF_ALIGNMENT);
|
|
efx->rx_bufs_per_page = efx->rx_buffer_order ? 1 :
|
|
((PAGE_SIZE - sizeof(struct efx_rx_page_state)) /
|
|
efx->rx_page_buf_step);
|
|
efx->rx_buffer_truesize = (PAGE_SIZE << efx->rx_buffer_order) /
|
|
efx->rx_bufs_per_page;
|
|
efx->rx_pages_per_batch = DIV_ROUND_UP(EFX_RX_PREFERRED_BATCH,
|
|
efx->rx_bufs_per_page);
|
|
}
|
|
|
|
/* efx_fast_push_rx_descriptors - push new RX descriptors quickly
|
|
* @rx_queue: RX descriptor queue
|
|
*
|
|
* This will aim to fill the RX descriptor queue up to
|
|
* @rx_queue->@max_fill. If there is insufficient atomic
|
|
* memory to do so, a slow fill will be scheduled.
|
|
*
|
|
* The caller must provide serialisation (none is used here). In practise,
|
|
* this means this function must run from the NAPI handler, or be called
|
|
* when NAPI is disabled.
|
|
*/
|
|
void efx_fast_push_rx_descriptors(struct efx_rx_queue *rx_queue, bool atomic)
|
|
{
|
|
struct efx_nic *efx = rx_queue->efx;
|
|
unsigned int fill_level, batch_size;
|
|
int space, rc = 0;
|
|
|
|
if (!rx_queue->refill_enabled)
|
|
return;
|
|
|
|
/* Calculate current fill level, and exit if we don't need to fill */
|
|
fill_level = (rx_queue->added_count - rx_queue->removed_count);
|
|
EFX_WARN_ON_ONCE_PARANOID(fill_level > rx_queue->efx->rxq_entries);
|
|
if (fill_level >= rx_queue->fast_fill_trigger)
|
|
goto out;
|
|
|
|
/* Record minimum fill level */
|
|
if (unlikely(fill_level < rx_queue->min_fill)) {
|
|
if (fill_level)
|
|
rx_queue->min_fill = fill_level;
|
|
}
|
|
|
|
batch_size = efx->rx_pages_per_batch * efx->rx_bufs_per_page;
|
|
space = rx_queue->max_fill - fill_level;
|
|
EFX_WARN_ON_ONCE_PARANOID(space < batch_size);
|
|
|
|
netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev,
|
|
"RX queue %d fast-filling descriptor ring from"
|
|
" level %d to level %d\n",
|
|
efx_rx_queue_index(rx_queue), fill_level,
|
|
rx_queue->max_fill);
|
|
|
|
do {
|
|
rc = efx_init_rx_buffers(rx_queue, atomic);
|
|
if (unlikely(rc)) {
|
|
/* Ensure that we don't leave the rx queue empty */
|
|
efx_schedule_slow_fill(rx_queue);
|
|
goto out;
|
|
}
|
|
} while ((space -= batch_size) >= batch_size);
|
|
|
|
netif_vdbg(rx_queue->efx, rx_status, rx_queue->efx->net_dev,
|
|
"RX queue %d fast-filled descriptor ring "
|
|
"to level %d\n", efx_rx_queue_index(rx_queue),
|
|
rx_queue->added_count - rx_queue->removed_count);
|
|
|
|
out:
|
|
if (rx_queue->notified_count != rx_queue->added_count)
|
|
efx_nic_notify_rx_desc(rx_queue);
|
|
}
|