tracing: Fix hwlat kthread migration

The hwlat tracer creates a kernel thread at start of the tracer. It is
pinned to a single CPU and will move to the next CPU after each period of
running. If the user modifies the migration thread's affinity, it will not
change after that happens.

The original code created the thread at the first instance it was called,
but later was changed to destroy the thread after the tracer was finished,
and would not be created until the next instance of the tracer was
established. The code that initialized the affinity was only called on the
initial instantiation of the tracer. After that, it was not initialized, and
the previous affinity did not match the current newly created one, making
it appear that the user modified the thread's affinity when it did not, and
the thread failed to migrate again.

Cc: stable@vger.kernel.org
Fixes: 0330f7aa8ee6 ("tracing: Have hwlat trace migrate across tracing_cpumask CPUs")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

path: root/sound/usb/6fire/chip.h

/*
 * Linux driver for TerraTec DMX 6Fire USB
 *
 * Author:	Torsten Schenk <torsten.schenk@zoho.com>
 * Created:	Jan 01, 2011
 * Copyright:	(C) Torsten Schenk
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */
#ifndef USB6FIRE_CHIP_H
#define USB6FIRE_CHIP_H

#include "common.h"

struct sfire_chip {
	struct usb_device *dev;
	struct snd_card *card;
	int intf_count; /* number of registered interfaces */
	int regidx; /* index in module parameter arrays */
	bool shutdown;

	struct midi_runtime *midi;
	struct pcm_runtime *pcm;
	struct control_runtime *control;
	struct comm_runtime *comm;
};
#endif /* USB6FIRE_CHIP_H */