Commit 0f532a78 authored by Lakshmi Sowjanya D's avatar Lakshmi Sowjanya D Committed by Thomas Gleixner
Browse files

x86/tsc: Remove obsolete ART to TSC conversion functions 



convert_art_to_tsc() and convert_art_ns_to_tsc() interfaces are no
longer required. The conversion is now handled by the core code.

Signed-off-by: default avatarLakshmi Sowjanya D <lakshmi.sowjanya.d@intel.com>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240513103813.5666-9-lakshmi.sowjanya.d@intel.com
parent d4bea547

arch/x86/include/asm/tsc.h

+0 −3
Original line number Diff line number Diff line
@@ -28,9 +28,6 @@ static inline cycles_t get_cycles(void) 
}

#define get_cycles get_cycles



extern struct system_counterval_t convert_art_to_tsc(u64 art);

extern struct system_counterval_t convert_art_ns_to_tsc(u64 art_ns);



extern void tsc_early_init(void);

extern void tsc_init(void);

extern void mark_tsc_unstable(char *reason);

arch/x86/kernel/tsc.c

+0 −60
Original line number Diff line number Diff line
@@ -1297,66 +1297,6 @@ int unsynchronized_tsc(void) 
	return 0;

}



/*

 * Convert ART to TSC given numerator/denominator found in detect_art()

 */

struct system_counterval_t convert_art_to_tsc(u64 art)

{

	u64 tmp, res, rem;



	rem = do_div(art, art_base_clk.denominator);



	res = art * art_base_clk.numerator;

	tmp = rem * art_base_clk.numerator;



	do_div(tmp, art_base_clk.denominator);

	res += tmp + art_base_clk.offset;



	return (struct system_counterval_t) {

		.cs_id	= have_art ? CSID_X86_TSC : CSID_GENERIC,

		.cycles	= res,

	};

}

EXPORT_SYMBOL(convert_art_to_tsc);



/**

 * convert_art_ns_to_tsc() - Convert ART in nanoseconds to TSC.

 * @art_ns: ART (Always Running Timer) in unit of nanoseconds

 *

 * PTM requires all timestamps to be in units of nanoseconds. When user

 * software requests a cross-timestamp, this function converts system timestamp

 * to TSC.

 *

 * This is valid when CPU feature flag X86_FEATURE_TSC_KNOWN_FREQ is set

 * indicating the tsc_khz is derived from CPUID[15H]. Drivers should check

 * that this flag is set before conversion to TSC is attempted.

 *

 * Return:

 * struct system_counterval_t - system counter value with the ID of the

 *	corresponding clocksource:

 *	cycles:		System counter value

 *	cs_id:		The clocksource ID for validating comparability

 */



struct system_counterval_t convert_art_ns_to_tsc(u64 art_ns)

{

	u64 tmp, res, rem;



	rem = do_div(art_ns, USEC_PER_SEC);



	res = art_ns * tsc_khz;

	tmp = rem * tsc_khz;



	do_div(tmp, USEC_PER_SEC);

	res += tmp;



	return (struct system_counterval_t) {

		.cs_id	= have_art ? CSID_X86_TSC : CSID_GENERIC,

		.cycles	= res,

	};

}

EXPORT_SYMBOL(convert_art_ns_to_tsc);



static void tsc_refine_calibration_work(struct work_struct *work);

static DECLARE_DELAYED_WORK(tsc_irqwork, tsc_refine_calibration_work);

/**