Revision 2bbd00aef0671bfe3c2ca5ba67097246257de125 authored by Johannes Weiner on 26 February 2021, 01:16:47 UTC, committed by Linus Torvalds on 26 February 2021, 17:41:00 UTC
On NOHZ, the periodic vmstat flushers on each CPU can go to sleep and
won't wake up until stat changes are detected in the per-cpu deltas of the
zone vmstat counters.

In commit 75ef71840539 ("mm, vmstat: add infrastructure for per-node
vmstats") per-node counters were introduced, and subsequently most stats
were moved from the zone to the node level.  However, the node counters
weren't added to the NOHZ wakeup detection.

In theory this can cause per-cpu errors to remain in the user-reported
stats indefinitely.  In practice this only affects a handful of sub
counters (file_mapped, dirty and writeback e.g.) because other page state
changes at the node level likely involve a change at the zone level as
well (alloc and free, lru ops).  Also, nobody has complained.

Fix it up for completeness: wake up vmstat refreshing on node changes.
Also remove the BUILD_BUG_ONs that assert counter size; we haven't relied
on it since we added sizeof() to the range calculation in commit
13c9aaf7fa01 ("mm/vmstat.c: fix NUMA statistics updates").

Link: https://lkml.kernel.org/r/20210202184342.118513-1-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent a052d4d
Raw File
hid-sjoy.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  Force feedback support for SmartJoy PLUS PS2->USB adapter
 *
 *  Copyright (c) 2009 Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
 *
 *  Based of hid-pl.c and hid-gaff.c
 *   Copyright (c) 2007, 2009 Anssi Hannula <anssi.hannula@gmail.com>
 *   Copyright (c) 2008 Lukasz Lubojanski <lukasz@lubojanski.info>
 */

/*
 */

/* #define DEBUG */

#include <linux/input.h>
#include <linux/slab.h>
#include <linux/hid.h>
#include <linux/module.h>
#include "hid-ids.h"

#ifdef CONFIG_SMARTJOYPLUS_FF

struct sjoyff_device {
	struct hid_report *report;
};

static int hid_sjoyff_play(struct input_dev *dev, void *data,
			 struct ff_effect *effect)
{
	struct hid_device *hid = input_get_drvdata(dev);
	struct sjoyff_device *sjoyff = data;
	u32 left, right;

	left = effect->u.rumble.strong_magnitude;
	right = effect->u.rumble.weak_magnitude;
	dev_dbg(&dev->dev, "called with 0x%08x 0x%08x\n", left, right);

	left = left * 0xff / 0xffff;
	right = (right != 0); /* on/off only */

	sjoyff->report->field[0]->value[1] = right;
	sjoyff->report->field[0]->value[2] = left;
	dev_dbg(&dev->dev, "running with 0x%02x 0x%02x\n", left, right);
	hid_hw_request(hid, sjoyff->report, HID_REQ_SET_REPORT);

	return 0;
}

static int sjoyff_init(struct hid_device *hid)
{
	struct sjoyff_device *sjoyff;
	struct hid_report *report;
	struct hid_input *hidinput;
	struct list_head *report_list =
			&hid->report_enum[HID_OUTPUT_REPORT].report_list;
	struct list_head *report_ptr = report_list;
	struct input_dev *dev;
	int error;

	if (list_empty(report_list)) {
		hid_err(hid, "no output reports found\n");
		return -ENODEV;
	}

	list_for_each_entry(hidinput, &hid->inputs, list) {
		report_ptr = report_ptr->next;

		if (report_ptr == report_list) {
			hid_err(hid, "required output report is missing\n");
			return -ENODEV;
		}

		report = list_entry(report_ptr, struct hid_report, list);
		if (report->maxfield < 1) {
			hid_err(hid, "no fields in the report\n");
			return -ENODEV;
		}

		if (report->field[0]->report_count < 3) {
			hid_err(hid, "not enough values in the field\n");
			return -ENODEV;
		}

		sjoyff = kzalloc(sizeof(struct sjoyff_device), GFP_KERNEL);
		if (!sjoyff)
			return -ENOMEM;

		dev = hidinput->input;

		set_bit(FF_RUMBLE, dev->ffbit);

		error = input_ff_create_memless(dev, sjoyff, hid_sjoyff_play);
		if (error) {
			kfree(sjoyff);
			return error;
		}

		sjoyff->report = report;
		sjoyff->report->field[0]->value[0] = 0x01;
		sjoyff->report->field[0]->value[1] = 0x00;
		sjoyff->report->field[0]->value[2] = 0x00;
		hid_hw_request(hid, sjoyff->report, HID_REQ_SET_REPORT);
	}

	hid_info(hid, "Force feedback for SmartJoy PLUS PS2/USB adapter\n");

	return 0;
}
#else
static inline int sjoyff_init(struct hid_device *hid)
{
	return 0;
}
#endif

static int sjoy_probe(struct hid_device *hdev, const struct hid_device_id *id)
{
	int ret;

	hdev->quirks |= id->driver_data;

	ret = hid_parse(hdev);
	if (ret) {
		hid_err(hdev, "parse failed\n");
		goto err;
	}

	ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT & ~HID_CONNECT_FF);
	if (ret) {
		hid_err(hdev, "hw start failed\n");
		goto err;
	}

	sjoyff_init(hdev);

	return 0;
err:
	return ret;
}

static const struct hid_device_id sjoy_devices[] = {
	{ HID_USB_DEVICE(USB_VENDOR_ID_WISEGROUP_LTD, USB_DEVICE_ID_SUPER_JOY_BOX_3_PRO),
		.driver_data = HID_QUIRK_NOGET },
	{ HID_USB_DEVICE(USB_VENDOR_ID_WISEGROUP_LTD, USB_DEVICE_ID_SUPER_DUAL_BOX_PRO),
		.driver_data = HID_QUIRK_MULTI_INPUT | HID_QUIRK_NOGET |
			       HID_QUIRK_SKIP_OUTPUT_REPORTS },
	{ HID_USB_DEVICE(USB_VENDOR_ID_WISEGROUP_LTD, USB_DEVICE_ID_SUPER_JOY_BOX_5_PRO),
		.driver_data = HID_QUIRK_MULTI_INPUT | HID_QUIRK_NOGET |
			       HID_QUIRK_SKIP_OUTPUT_REPORTS },
	{ HID_USB_DEVICE(USB_VENDOR_ID_WISEGROUP, USB_DEVICE_ID_SMARTJOY_PLUS) },
	{ HID_USB_DEVICE(USB_VENDOR_ID_WISEGROUP, USB_DEVICE_ID_SUPER_JOY_BOX_3) },
	{ HID_USB_DEVICE(USB_VENDOR_ID_WISEGROUP, USB_DEVICE_ID_DUAL_USB_JOYPAD),
		.driver_data = HID_QUIRK_MULTI_INPUT |
			       HID_QUIRK_SKIP_OUTPUT_REPORTS },
	{ HID_USB_DEVICE(USB_VENDOR_ID_PLAYDOTCOM, USB_DEVICE_ID_PLAYDOTCOM_EMS_USBII),
		.driver_data = HID_QUIRK_MULTI_INPUT |
			       HID_QUIRK_SKIP_OUTPUT_REPORTS },
	{ }
};
MODULE_DEVICE_TABLE(hid, sjoy_devices);

static struct hid_driver sjoy_driver = {
	.name = "smartjoyplus",
	.id_table = sjoy_devices,
	.probe = sjoy_probe,
};
module_hid_driver(sjoy_driver);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Jussi Kivilinna");

back to top