Revision 6e474083f3daf3a3546737f5d7d502ad12eb257c authored by Wei Xu on 01 December 2017, 10:10:36 UTC, committed by David S. Miller on 03 December 2017, 02:31:03 UTC
Matthew found a roughly 40% tcp throughput regression with commit c67df11f(vhost_net: try batch dequing from skb array) as discussed in the following thread: https://www.mail-archive.com/netdev@vger.kernel.org/msg187936.html Eventually we figured out that it was a skb leak in handle_rx() when sending packets to the VM. This usually happens when a guest can not drain out vq as fast as vhost fills in, afterwards it sets off the traffic jam and leaks skb(s) which occurs as no headcount to send on the vq from vhost side. This can be avoided by making sure we have got enough headcount before actually consuming a skb from the batched rx array while transmitting, which is simply done by moving checking the zero headcount a bit ahead. Signed-off-by: Wei Xu <wexu@redhat.com> Reported-by: Matthew Rosato <mjrosato@linux.vnet.ibm.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
1 parent fa935ca
leds-88pm860x.c
/*
* LED driver for Marvell 88PM860x
*
* Copyright (C) 2009 Marvell International Ltd.
* Haojian Zhuang <haojian.zhuang@marvell.com>
*
* 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.
*
*/
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/i2c.h>
#include <linux/leds.h>
#include <linux/slab.h>
#include <linux/mfd/88pm860x.h>
#include <linux/module.h>
#define LED_PWM_MASK (0x1F)
#define LED_CURRENT_MASK (0x07 << 5)
#define LED_BLINK_MASK (0x7F)
#define LED_ON_CONTINUOUS (0x0F << 3)
#define LED1_BLINK_EN (1 << 1)
#define LED2_BLINK_EN (1 << 2)
struct pm860x_led {
struct led_classdev cdev;
struct i2c_client *i2c;
struct pm860x_chip *chip;
struct mutex lock;
char name[MFD_NAME_SIZE];
int port;
int iset;
unsigned char brightness;
unsigned char current_brightness;
int reg_control;
int reg_blink;
int blink_mask;
};
static int led_power_set(struct pm860x_chip *chip, int port, int on)
{
int ret = -EINVAL;
switch (port) {
case 0:
case 1:
case 2:
ret = on ? pm8606_osc_enable(chip, RGB1_ENABLE) :
pm8606_osc_disable(chip, RGB1_ENABLE);
break;
case 3:
case 4:
case 5:
ret = on ? pm8606_osc_enable(chip, RGB2_ENABLE) :
pm8606_osc_disable(chip, RGB2_ENABLE);
break;
}
return ret;
}
static int pm860x_led_set(struct led_classdev *cdev,
enum led_brightness value)
{
struct pm860x_led *led = container_of(cdev, struct pm860x_led, cdev);
struct pm860x_chip *chip;
unsigned char buf[3];
int ret;
chip = led->chip;
mutex_lock(&led->lock);
led->brightness = value >> 3;
if ((led->current_brightness == 0) && led->brightness) {
led_power_set(chip, led->port, 1);
if (led->iset) {
pm860x_set_bits(led->i2c, led->reg_control,
LED_CURRENT_MASK, led->iset);
}
pm860x_set_bits(led->i2c, led->reg_blink,
LED_BLINK_MASK, LED_ON_CONTINUOUS);
pm860x_set_bits(led->i2c, PM8606_WLED3B, led->blink_mask,
led->blink_mask);
}
pm860x_set_bits(led->i2c, led->reg_control, LED_PWM_MASK,
led->brightness);
if (led->brightness == 0) {
pm860x_bulk_read(led->i2c, led->reg_control, 3, buf);
ret = buf[0] & LED_PWM_MASK;
ret |= buf[1] & LED_PWM_MASK;
ret |= buf[2] & LED_PWM_MASK;
if (ret == 0) {
/* unset current since no led is lighting */
pm860x_set_bits(led->i2c, led->reg_control,
LED_CURRENT_MASK, 0);
pm860x_set_bits(led->i2c, PM8606_WLED3B,
led->blink_mask, 0);
led_power_set(chip, led->port, 0);
}
}
led->current_brightness = led->brightness;
dev_dbg(chip->dev, "Update LED. (reg:%d, brightness:%d)\n",
led->reg_control, led->brightness);
mutex_unlock(&led->lock);
return 0;
}
#ifdef CONFIG_OF
static int pm860x_led_dt_init(struct platform_device *pdev,
struct pm860x_led *data)
{
struct device_node *nproot, *np;
int iset = 0;
if (!pdev->dev.parent->of_node)
return -ENODEV;
nproot = of_get_child_by_name(pdev->dev.parent->of_node, "leds");
if (!nproot) {
dev_err(&pdev->dev, "failed to find leds node\n");
return -ENODEV;
}
for_each_child_of_node(nproot, np) {
if (!of_node_cmp(np->name, data->name)) {
of_property_read_u32(np, "marvell,88pm860x-iset",
&iset);
data->iset = PM8606_LED_CURRENT(iset);
of_node_put(np);
break;
}
}
of_node_put(nproot);
return 0;
}
#else
#define pm860x_led_dt_init(x, y) (-1)
#endif
static int pm860x_led_probe(struct platform_device *pdev)
{
struct pm860x_chip *chip = dev_get_drvdata(pdev->dev.parent);
struct pm860x_led_pdata *pdata = dev_get_platdata(&pdev->dev);
struct pm860x_led *data;
struct resource *res;
int ret = 0;
data = devm_kzalloc(&pdev->dev, sizeof(struct pm860x_led), GFP_KERNEL);
if (data == NULL)
return -ENOMEM;
res = platform_get_resource_byname(pdev, IORESOURCE_REG, "control");
if (!res) {
dev_err(&pdev->dev, "No REG resource for control\n");
return -ENXIO;
}
data->reg_control = res->start;
res = platform_get_resource_byname(pdev, IORESOURCE_REG, "blink");
if (!res) {
dev_err(&pdev->dev, "No REG resource for blink\n");
return -ENXIO;
}
data->reg_blink = res->start;
memset(data->name, 0, MFD_NAME_SIZE);
switch (pdev->id) {
case 0:
data->blink_mask = LED1_BLINK_EN;
sprintf(data->name, "led0-red");
break;
case 1:
data->blink_mask = LED1_BLINK_EN;
sprintf(data->name, "led0-green");
break;
case 2:
data->blink_mask = LED1_BLINK_EN;
sprintf(data->name, "led0-blue");
break;
case 3:
data->blink_mask = LED2_BLINK_EN;
sprintf(data->name, "led1-red");
break;
case 4:
data->blink_mask = LED2_BLINK_EN;
sprintf(data->name, "led1-green");
break;
case 5:
data->blink_mask = LED2_BLINK_EN;
sprintf(data->name, "led1-blue");
break;
}
data->chip = chip;
data->i2c = (chip->id == CHIP_PM8606) ? chip->client : chip->companion;
data->port = pdev->id;
if (pm860x_led_dt_init(pdev, data))
if (pdata)
data->iset = pdata->iset;
data->current_brightness = 0;
data->cdev.name = data->name;
data->cdev.brightness_set_blocking = pm860x_led_set;
mutex_init(&data->lock);
ret = devm_led_classdev_register(chip->dev, &data->cdev);
if (ret < 0) {
dev_err(&pdev->dev, "Failed to register LED: %d\n", ret);
return ret;
}
pm860x_led_set(&data->cdev, 0);
return 0;
}
static struct platform_driver pm860x_led_driver = {
.driver = {
.name = "88pm860x-led",
},
.probe = pm860x_led_probe,
};
module_platform_driver(pm860x_led_driver);
MODULE_DESCRIPTION("LED driver for Marvell PM860x");
MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:88pm860x-led");
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