linux_dsm_epyc7002/net/core/hwbm.c
Sebastian Andrzej Siewior 6dcdd884e2 net: hwbm: Make the hwbm_pool lock a mutex
Based on review, `lock' is only acquired in hwbm_pool_add() which is
invoked via ->probe(), ->resume() and ->ndo_change_mtu(). Based on this
the lock can become a mutex and there is no need to disable interrupts
during the procedure.
Now that the lock is a mutex, hwbm_pool_add() no longer invokes
hwbm_pool_refill() in an atomic context so we can pass GFP_KERNEL to
hwbm_pool_refill() and remove the `gfp' argument from hwbm_pool_add().

Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-09 19:40:10 -07:00

86 lines
1.9 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/* Support for hardware buffer manager.
*
* Copyright (C) 2016 Marvell
*
* Gregory CLEMENT <gregory.clement@free-electrons.com>
*/
#include <linux/kernel.h>
#include <linux/printk.h>
#include <linux/skbuff.h>
#include <net/hwbm.h>
void hwbm_buf_free(struct hwbm_pool *bm_pool, void *buf)
{
if (likely(bm_pool->frag_size <= PAGE_SIZE))
skb_free_frag(buf);
else
kfree(buf);
}
EXPORT_SYMBOL_GPL(hwbm_buf_free);
/* Refill processing for HW buffer management */
int hwbm_pool_refill(struct hwbm_pool *bm_pool, gfp_t gfp)
{
int frag_size = bm_pool->frag_size;
void *buf;
if (likely(frag_size <= PAGE_SIZE))
buf = netdev_alloc_frag(frag_size);
else
buf = kmalloc(frag_size, gfp);
if (!buf)
return -ENOMEM;
if (bm_pool->construct)
if (bm_pool->construct(bm_pool, buf)) {
hwbm_buf_free(bm_pool, buf);
return -ENOMEM;
}
return 0;
}
EXPORT_SYMBOL_GPL(hwbm_pool_refill);
int hwbm_pool_add(struct hwbm_pool *bm_pool, unsigned int buf_num)
{
int err, i;
mutex_lock(&bm_pool->buf_lock);
if (bm_pool->buf_num == bm_pool->size) {
pr_warn("pool already filled\n");
mutex_unlock(&bm_pool->buf_lock);
return bm_pool->buf_num;
}
if (buf_num + bm_pool->buf_num > bm_pool->size) {
pr_warn("cannot allocate %d buffers for pool\n",
buf_num);
mutex_unlock(&bm_pool->buf_lock);
return 0;
}
if ((buf_num + bm_pool->buf_num) < bm_pool->buf_num) {
pr_warn("Adding %d buffers to the %d current buffers will overflow\n",
buf_num, bm_pool->buf_num);
mutex_unlock(&bm_pool->buf_lock);
return 0;
}
for (i = 0; i < buf_num; i++) {
err = hwbm_pool_refill(bm_pool, GFP_KERNEL);
if (err < 0)
break;
}
/* Update BM driver with number of buffers added to pool */
bm_pool->buf_num += i;
pr_debug("hwpm pool: %d of %d buffers added\n", i, buf_num);
mutex_unlock(&bm_pool->buf_lock);
return i;
}
EXPORT_SYMBOL_GPL(hwbm_pool_add);