Staging
v0.6.0
v0.6.0
Revision a0783cd0c810504427777e8aae20d5f4f8b652a0 authored by Corinna Vinschen on 19 November 2019, 09:09:39 UTC, committed by David S. Miller on 20 November 2019, 00:41:11 UTC
During performance testing, I found that one of my r8169 NICs suffered a major performance loss, a 8168c model. Running netperf's TCP_STREAM test didn't return the expected throughput of > 900 Mb/s, but rather only about 22 Mb/s. Strange enough, running the TCP_MAERTS and UDP_STREAM tests all returned with throughput > 900 Mb/s, as did TCP_STREAM with the other r8169 NICs I can test (either one of 8169s, 8168e, 8168f). Bisecting turned up commit 93681cd7d94f83903cb3f0f95433d10c28a7e9a5, "r8169: enable HW csum and TSO" as the culprit. I added my 8168c version, RTL_GIGA_MAC_VER_22, to the code special-casing the 8168evl as per the patch below. This fixed the performance problem for me. Fixes: 93681cd7d94f ("r8169: enable HW csum and TSO") Signed-off-by: Corinna Vinschen <vinschen@redhat.com> Reviewed-by: Heiner Kallweit <hkallweit1@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
1 parent c9d55b6
test_list_sort.c
// SPDX-License-Identifier: GPL-2.0-only
#define pr_fmt(fmt) "list_sort_test: " fmt
#include <linux/kernel.h>
#include <linux/list_sort.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/printk.h>
#include <linux/slab.h>
#include <linux/random.h>
/*
* The pattern of set bits in the list length determines which cases
* are hit in list_sort().
*/
#define TEST_LIST_LEN (512+128+2) /* not including head */
#define TEST_POISON1 0xDEADBEEF
#define TEST_POISON2 0xA324354C
struct debug_el {
unsigned int poison1;
struct list_head list;
unsigned int poison2;
int value;
unsigned serial;
};
/* Array, containing pointers to all elements in the test list */
static struct debug_el **elts __initdata;
static int __init check(struct debug_el *ela, struct debug_el *elb)
{
if (ela->serial >= TEST_LIST_LEN) {
pr_err("error: incorrect serial %d\n", ela->serial);
return -EINVAL;
}
if (elb->serial >= TEST_LIST_LEN) {
pr_err("error: incorrect serial %d\n", elb->serial);
return -EINVAL;
}
if (elts[ela->serial] != ela || elts[elb->serial] != elb) {
pr_err("error: phantom element\n");
return -EINVAL;
}
if (ela->poison1 != TEST_POISON1 || ela->poison2 != TEST_POISON2) {
pr_err("error: bad poison: %#x/%#x\n",
ela->poison1, ela->poison2);
return -EINVAL;
}
if (elb->poison1 != TEST_POISON1 || elb->poison2 != TEST_POISON2) {
pr_err("error: bad poison: %#x/%#x\n",
elb->poison1, elb->poison2);
return -EINVAL;
}
return 0;
}
static int __init cmp(void *priv, struct list_head *a, struct list_head *b)
{
struct debug_el *ela, *elb;
ela = container_of(a, struct debug_el, list);
elb = container_of(b, struct debug_el, list);
check(ela, elb);
return ela->value - elb->value;
}
static int __init list_sort_test(void)
{
int i, count = 1, err = -ENOMEM;
struct debug_el *el;
struct list_head *cur;
LIST_HEAD(head);
pr_debug("start testing list_sort()\n");
elts = kcalloc(TEST_LIST_LEN, sizeof(*elts), GFP_KERNEL);
if (!elts)
return err;
for (i = 0; i < TEST_LIST_LEN; i++) {
el = kmalloc(sizeof(*el), GFP_KERNEL);
if (!el)
goto exit;
/* force some equivalencies */
el->value = prandom_u32() % (TEST_LIST_LEN / 3);
el->serial = i;
el->poison1 = TEST_POISON1;
el->poison2 = TEST_POISON2;
elts[i] = el;
list_add_tail(&el->list, &head);
}
list_sort(NULL, &head, cmp);
err = -EINVAL;
for (cur = head.next; cur->next != &head; cur = cur->next) {
struct debug_el *el1;
int cmp_result;
if (cur->next->prev != cur) {
pr_err("error: list is corrupted\n");
goto exit;
}
cmp_result = cmp(NULL, cur, cur->next);
if (cmp_result > 0) {
pr_err("error: list is not sorted\n");
goto exit;
}
el = container_of(cur, struct debug_el, list);
el1 = container_of(cur->next, struct debug_el, list);
if (cmp_result == 0 && el->serial >= el1->serial) {
pr_err("error: order of equivalent elements not "
"preserved\n");
goto exit;
}
if (check(el, el1)) {
pr_err("error: element check failed\n");
goto exit;
}
count++;
}
if (head.prev != cur) {
pr_err("error: list is corrupted\n");
goto exit;
}
if (count != TEST_LIST_LEN) {
pr_err("error: bad list length %d", count);
goto exit;
}
err = 0;
exit:
for (i = 0; i < TEST_LIST_LEN; i++)
kfree(elts[i]);
kfree(elts);
return err;
}
module_init(list_sort_test);
MODULE_LICENSE("GPL");
Computing file changes ...