提交 1751cc36 编写于 作者: A Alex Maftei (amaftei) 提交者: David S. Miller

sfc: move common rx code

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: NAlexandru-Mihai Maftei <amaftei@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
上级 5f999256
# SPDX-License-Identifier: GPL-2.0
sfc-y += efx.o efx_common.o efx_channels.o nic.o \
farch.o siena.o ef10.o \
tx.o rx.o \
tx.o rx.o rx_common.o \
selftest.o ethtool.o ptp.o tx_tso.o \
mcdi.o mcdi_port.o \
mcdi_mon.o
......
......@@ -5,6 +5,7 @@
*/
#include "net_driver.h"
#include "rx_common.h"
#include "ef10_regs.h"
#include "io.h"
#include "mcdi.h"
......
......@@ -128,17 +128,6 @@ static int efx_xdp_xmit(struct net_device *dev, int n, struct xdp_frame **xdpfs,
ASSERT_RTNL(); \
} while (0)
/**************************************************************************
*
* Channel handling
*
*************************************************************************/
void efx_schedule_slow_fill(struct efx_rx_queue *rx_queue)
{
mod_timer(&rx_queue->slow_fill, jiffies + msecs_to_jiffies(10));
}
/**************************************************************************
*
* Port handling
......
......@@ -37,6 +37,9 @@ static inline void efx_rx_flush_packet(struct efx_channel *channel)
__efx_rx_packet(channel);
}
void efx_init_rx_recycle_ring(struct efx_rx_queue *rx_queue);
struct page *efx_reuse_page(struct efx_rx_queue *rx_queue);
#define EFX_MAX_DMAQ_SIZE 4096UL
#define EFX_DEFAULT_DMAQ_SIZE 1024UL
#define EFX_MIN_DMAQ_SIZE 512UL
......
......@@ -43,23 +43,10 @@
/* Size of buffer allocated for skb header area. */
#define EFX_SKB_HEADERS 128u
/* 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;
/* Each packet can consume up to ceil(max_frame_len / buffer_size) buffers */
#define EFX_RX_MAX_FRAGS DIV_ROUND_UP(EFX_MAX_FRAME_LEN(EFX_MAX_MTU), \
EFX_RX_USR_BUF_SIZE)
/*
* 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 inline u8 *efx_rx_buf_va(struct efx_rx_buffer *buf)
{
return page_address(buf->page) + buf->page_offset;
......@@ -86,22 +73,8 @@ static inline void efx_sync_rx_buffer(struct efx_nic *efx,
DMA_FROM_DEVICE);
}
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);
}
/* Check the RX page recycle ring for a page that can be reused. */
static struct page *efx_reuse_page(struct efx_rx_queue *rx_queue)
struct page *efx_reuse_page(struct efx_rx_queue *rx_queue)
{
struct efx_nic *efx = rx_queue->efx;
struct page *page;
......@@ -134,106 +107,6 @@ static struct page *efx_reuse_page(struct efx_rx_queue *rx_queue)
return NULL;
}
/**
* 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.
*/
int efx_init_rx_buffers(struct efx_rx_queue *rx_queue, bool atomic)
{
struct efx_nic *efx = rx_queue->efx;
struct efx_rx_buffer *rx_buf;
struct page *page;
unsigned int page_offset;
struct efx_rx_page_state *state;
dma_addr_t dma_addr;
unsigned index, count;
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;
}
/* 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);
}
/* Attempt to recycle the page if there is an RX recycle ring; the page can
* only be added if this is the final RX buffer, to prevent pages being used in
* the descriptor ring and appearing in the recycle ring simultaneously.
......@@ -270,21 +143,6 @@ static void efx_recycle_rx_page(struct efx_channel *channel,
put_page(rx_buf->page);
}
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;
}
/* Recycle the pages that are used by buffers that have just been received. */
static void efx_recycle_rx_pages(struct efx_channel *channel,
struct efx_rx_buffer *rx_buf,
......@@ -309,78 +167,6 @@ static void efx_discard_rx_packet(struct efx_channel *channel,
efx_free_rx_buffers(rx_queue, rx_buf, n_frags);
}
/**
* 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);
}
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;
}
static void efx_rx_packet__check_len(struct efx_rx_queue *rx_queue,
struct efx_rx_buffer *rx_buf,
int len)
......@@ -797,41 +583,10 @@ void __efx_rx_packet(struct efx_channel *channel)
channel->rx_pkt_n_frags = 0;
}
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;
}
static void efx_init_rx_recycle_ring(struct efx_nic *efx,
struct efx_rx_queue *rx_queue)
void efx_init_rx_recycle_ring(struct efx_rx_queue *rx_queue)
{
unsigned int bufs_in_recycle_ring, page_ring_size;
struct efx_nic *efx = rx_queue->efx;
/* Set the RX recycle ring size */
#ifdef CONFIG_PPC64
......@@ -850,121 +605,6 @@ static void efx_init_rx_recycle_ring(struct efx_nic *efx,
rx_queue->page_ptr_mask = page_ring_size - 1;
}
void efx_init_rx_queue(struct efx_rx_queue *rx_queue)
{
struct efx_nic *efx = rx_queue->efx;
unsigned int max_fill, trigger, max_trigger;
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(efx, 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)
{
int i;
struct efx_nic *efx = rx_queue->efx;
struct efx_rx_buffer *rx_buf;
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 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;
}
module_param(rx_refill_threshold, uint, 0444);
MODULE_PARM_DESC(rx_refill_threshold,
"RX descriptor ring refill threshold (%)");
#ifdef CONFIG_RFS_ACCEL
static void efx_filter_rfs_work(struct work_struct *data)
......
// 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);
}
Markdown is supported
0% .
You are about to add 0 people to the discussion. Proceed with caution.
先完成此消息的编辑!
想要评论请 注册