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#ifndef __TRACE_STAT_H
#define __TRACE_STAT_H

#include <linux/seq_file.h>

/*
 * If you want to provide a stat file (one-shot statistics), fill
 * an iterator with stat_start/stat_next and a stat_show callbacks.
 * The others callbacks are optional.
 */
struct tracer_stat {
	/* The name of your stat file */
	const char		*name;
	/* Iteration over statistic entries */
	void			*(*stat_start)(struct tracer_stat *trace);
	void			*(*stat_next)(void *prev, int idx);
	/* Compare two entries for stats sorting */
	int			(*stat_cmp)(void *p1, void *p2);
	/* Print a stat entry */
	int			(*stat_show)(struct seq_file *s, void *p);
	/* Release an entry */
	void			(*stat_release)(void *stat);
	/* Print the headers of your stat entries */
	int			(*stat_headers)(struct seq_file *s);
};

/*
 * Destroy or create a stat file
 */
extern int register_stat_tracer(struct tracer_stat *trace);
extern void unregister_stat_tracer(struct tracer_stat *trace);

#endif /* __TRACE_STAT_H */
efficiency setting -- MSR_IA32_POWER_CTL BIT-EE, which is not recommended to be enabled on this SKU. On the failing systems, this BIOS issue was not discovered when the desktop motherboard was tested with Windows, because the BIOS also neglects to provide the ACPI/CPPC table, that Windows requires to enable HWP, and so Windows runs in legacy P-state mode, where this setting has no effect. Linux' intel_pstate driver does not require ACPI/CPPC to enable HWP, and so it runs in HWP mode, exposing this incorrect BIOS configuration. There are several ways to address this problem. First, Linux can also run in legacy P-state mode on this system. As intel_pstate is how Linux enables HWP, booting with "intel_pstate=disable" will run in acpi-cpufreq/ondemand legacy p-state mode. Or second, the "performance" governor can be used with intel_pstate, which will modify HWP.EPP to 0. Or third, starting in 4.10, the /sys/devices/system/cpu/cpufreq/policy*/energy_performance_preference attribute in can be updated from "balance_power" to "performance". Or fourth, apply this patch, which fixes the erroneous setting of MSR_IA32_POWER_CTL BIT_EE on this model, allowing the default configuration to function as designed. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Reviewed-by: Len Brown <len.brown@intel.com> Cc: 4.6+ <stable@vger.kernel.org> # 4.6+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'fs/autofs4')