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Commit 3aefbe07 authored by Andi Kleen's avatar Andi Kleen Committed by Andi Kleen
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[PATCH] i386: Implement X86_FEATURE_SYNC_RDTSC on i386 



Syncs up with x86-64.

Signed-off-by: default avatarAndi Kleen <ak@suse.de>
parent e859dc55

arch/i386/kernel/cpu/intel.c

+3 −1
Original line number Diff line number Diff line
@@ -188,8 +188,10 @@ static void __cpuinit init_intel(struct cpuinfo_x86 *c) 
	}

#endif



	if (c->x86 == 15)

	if (c->x86 == 15) {

		set_bit(X86_FEATURE_P4, c->x86_capability);

		set_bit(X86_FEATURE_SYNC_RDTSC, c->x86_capability);

	}

	if (c->x86 == 6) 

		set_bit(X86_FEATURE_P3, c->x86_capability);

	if ((c->x86 == 0xf && c->x86_model >= 0x03) ||

include/asm-i386/cpufeature.h

+1 −0
Original line number Diff line number Diff line
@@ -79,6 +79,7 @@ 
#define X86_FEATURE_PEBS	(3*32+12)  /* Precise-Event Based Sampling */

#define X86_FEATURE_BTS		(3*32+13)  /* Branch Trace Store */

#define X86_FEATURE_LAPIC_TIMER_BROKEN (3*32+ 14) /* lapic timer broken in C1 */

#define X86_FEATURE_SYNC_RDTSC	(3*32+15)  /* RDTSC synchronizes the CPU */



/* Intel-defined CPU features, CPUID level 0x00000001 (ecx), word 4 */

#define X86_FEATURE_XMM3	(4*32+ 0) /* Streaming SIMD Extensions-3 */

include/asm-i386/tsc.h

+0 −4
Original line number Diff line number Diff line
@@ -35,7 +35,6 @@ static inline cycles_t get_cycles(void) 
static __always_inline cycles_t get_cycles_sync(void)

{

	unsigned long long ret;

#ifdef X86_FEATURE_SYNC_RDTSC

	unsigned eax;



	/*
@@ -44,9 +43,6 @@ static __always_inline cycles_t get_cycles_sync(void) 
	 */

	alternative_io("cpuid", ASM_NOP2, X86_FEATURE_SYNC_RDTSC,

			  "=a" (eax), "0" (1) : "ebx","ecx","edx","memory");

#else

	sync_core();

#endif

	rdtscll(ret);



	return ret;