Commit 7745f03e authored by Len Brown's avatar Len Brown Committed by Thomas Gleixner
Browse files

x86/topology: Add CPUID.1F multi-die/package support 



Some new systems have multiple software-visible die within each package.

Update Linux parsing of the Intel CPUID "Extended Topology Leaf" to handle
either CPUID.B, or the new CPUID.1F.

Add cpuinfo_x86.die_id and cpuinfo_x86.max_dies to store the result.

die_id will be non-zero only for multi-die/package systems.

Signed-off-by: default avatarLen Brown <len.brown@intel.com>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Reviewed-by: default avatarIngo Molnar <mingo@kernel.org>
Acked-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: linux-doc@vger.kernel.org
Link: https://lkml.kernel.org/r/7b23d2d26d717b8e14ba137c94b70943f1ae4b5c.1557769318.git.len.brown@intel.com
parent a188339c

Documentation/x86/topology.rst

+4 −0
Original line number Diff line number Diff line
@@ -49,6 +49,10 @@ Package-related topology information in the kernel: 


    The number of cores in a package. This information is retrieved via CPUID.



  - cpuinfo_x86.x86_max_dies:



    The number of dies in a package. This information is retrieved via CPUID.



  - cpuinfo_x86.phys_proc_id:



    The physical ID of the package. This information is retrieved via CPUID

arch/x86/include/asm/processor.h

+3 −1
Original line number Diff line number Diff line
@@ -106,6 +106,7 @@ struct cpuinfo_x86 { 
	unsigned long		loops_per_jiffy;

	/* cpuid returned max cores value: */

	u16			x86_max_cores;

	u16			x86_max_dies;

	u16			apicid;

	u16			initial_apicid;

	u16			x86_clflush_size;
@@ -117,6 +118,7 @@ struct cpuinfo_x86 { 
	u16			logical_proc_id;

	/* Core id: */

	u16			cpu_core_id;

	u16			cpu_die_id;

	/* Index into per_cpu list: */

	u16			cpu_index;

	u32			microcode;

arch/x86/kernel/cpu/topology.c

+66 −19
Original line number Diff line number Diff line
@@ -15,33 +15,63 @@ 
/* leaf 0xb SMT level */

#define SMT_LEVEL	0



/* leaf 0xb sub-leaf types */

/* extended topology sub-leaf types */

#define INVALID_TYPE	0

#define SMT_TYPE	1

#define CORE_TYPE	2

#define DIE_TYPE	5



#define LEAFB_SUBTYPE(ecx)		(((ecx) >> 8) & 0xff)

#define BITS_SHIFT_NEXT_LEVEL(eax)	((eax) & 0x1f)

#define LEVEL_MAX_SIBLINGS(ebx)		((ebx) & 0xffff)



int detect_extended_topology_early(struct cpuinfo_x86 *c)

{

#ifdef CONFIG_SMP

/*

 * Check if given CPUID extended toplogy "leaf" is implemented

 */

static int check_extended_topology_leaf(int leaf)

{

	unsigned int eax, ebx, ecx, edx;



	if (c->cpuid_level < 0xb)

		return -1;

	cpuid_count(leaf, SMT_LEVEL, &eax, &ebx, &ecx, &edx);



	cpuid_count(0xb, SMT_LEVEL, &eax, &ebx, &ecx, &edx);

	if (ebx == 0 || (LEAFB_SUBTYPE(ecx) != SMT_TYPE))

		return -1;



	return 0;

}

/*

	 * check if the cpuid leaf 0xb is actually implemented.

 * Return best CPUID Extended Toplogy Leaf supported

 */

	if (ebx == 0 || (LEAFB_SUBTYPE(ecx) != SMT_TYPE))

static int detect_extended_topology_leaf(struct cpuinfo_x86 *c)

{

	if (c->cpuid_level >= 0x1f) {

		if (check_extended_topology_leaf(0x1f) == 0)

			return 0x1f;

	}



	if (c->cpuid_level >= 0xb) {

		if (check_extended_topology_leaf(0xb) == 0)

			return 0xb;

	}



	return -1;

}

#endif



int detect_extended_topology_early(struct cpuinfo_x86 *c)

{

#ifdef CONFIG_SMP

	unsigned int eax, ebx, ecx, edx;

	int leaf;



	leaf = detect_extended_topology_leaf(c);

	if (leaf < 0)

		return -1;



	set_cpu_cap(c, X86_FEATURE_XTOPOLOGY);



	cpuid_count(leaf, SMT_LEVEL, &eax, &ebx, &ecx, &edx);

	/*

	 * initial apic id, which also represents 32-bit extended x2apic id.

	 */
@@ -52,7 +82,7 @@ int detect_extended_topology_early(struct cpuinfo_x86 *c) 
}



/*

 * Check for extended topology enumeration cpuid leaf 0xb and if it

 * Check for extended topology enumeration cpuid leaf, and if it

 * exists, use it for populating initial_apicid and cpu topology

 * detection.

 */
@@ -60,22 +90,28 @@ int detect_extended_topology(struct cpuinfo_x86 *c) 
{

#ifdef CONFIG_SMP

	unsigned int eax, ebx, ecx, edx, sub_index;

	unsigned int ht_mask_width, core_plus_mask_width;

	unsigned int ht_mask_width, core_plus_mask_width, die_plus_mask_width;

	unsigned int core_select_mask, core_level_siblings;

	unsigned int die_select_mask, die_level_siblings;

	int leaf;



	if (detect_extended_topology_early(c) < 0)

	leaf = detect_extended_topology_leaf(c);

	if (leaf < 0)

		return -1;



	/*

	 * Populate HT related information from sub-leaf level 0.

	 */

	cpuid_count(0xb, SMT_LEVEL, &eax, &ebx, &ecx, &edx);

	cpuid_count(leaf, SMT_LEVEL, &eax, &ebx, &ecx, &edx);

	c->initial_apicid = edx;

	core_level_siblings = smp_num_siblings = LEVEL_MAX_SIBLINGS(ebx);

	core_plus_mask_width = ht_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);

	die_level_siblings = LEVEL_MAX_SIBLINGS(ebx);

	die_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);



	sub_index = 1;

	do {

		cpuid_count(0xb, sub_index, &eax, &ebx, &ecx, &edx);

		cpuid_count(leaf, sub_index, &eax, &ebx, &ecx, &edx);



		/*

		 * Check for the Core type in the implemented sub leaves.
@@ -83,23 +119,34 @@ int detect_extended_topology(struct cpuinfo_x86 *c) 
		if (LEAFB_SUBTYPE(ecx) == CORE_TYPE) {

			core_level_siblings = LEVEL_MAX_SIBLINGS(ebx);

			core_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);

			break;

			die_level_siblings = core_level_siblings;

			die_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);

		}

		if (LEAFB_SUBTYPE(ecx) == DIE_TYPE) {

			die_level_siblings = LEVEL_MAX_SIBLINGS(ebx);

			die_plus_mask_width = BITS_SHIFT_NEXT_LEVEL(eax);

		}



		sub_index++;

	} while (LEAFB_SUBTYPE(ecx) != INVALID_TYPE);



	core_select_mask = (~(-1 << core_plus_mask_width)) >> ht_mask_width;



	c->cpu_core_id = apic->phys_pkg_id(c->initial_apicid, ht_mask_width)

						 & core_select_mask;

	c->phys_proc_id = apic->phys_pkg_id(c->initial_apicid, core_plus_mask_width);

	die_select_mask = (~(-1 << die_plus_mask_width)) >>

				core_plus_mask_width;



	c->cpu_core_id = apic->phys_pkg_id(c->initial_apicid,

				ht_mask_width) & core_select_mask;

	c->cpu_die_id = apic->phys_pkg_id(c->initial_apicid,

				core_plus_mask_width) & die_select_mask;

	c->phys_proc_id = apic->phys_pkg_id(c->initial_apicid,

				die_plus_mask_width);

	/*

	 * Reinit the apicid, now that we have extended initial_apicid.

	 */

	c->apicid = apic->phys_pkg_id(c->initial_apicid, 0);



	c->x86_max_cores = (core_level_siblings / smp_num_siblings);

	c->x86_max_dies = (die_level_siblings / core_level_siblings);

#endif

	return 0;

}

arch/x86/kernel/smpboot.c

+2 −0
Original line number Diff line number Diff line
@@ -389,6 +389,7 @@ static bool match_smt(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o) 
		int cpu1 = c->cpu_index, cpu2 = o->cpu_index;



		if (c->phys_proc_id == o->phys_proc_id &&

		    c->cpu_die_id == o->cpu_die_id &&

		    per_cpu(cpu_llc_id, cpu1) == per_cpu(cpu_llc_id, cpu2)) {

			if (c->cpu_core_id == o->cpu_core_id)

				return topology_sane(c, o, "smt");
@@ -400,6 +401,7 @@ static bool match_smt(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o) 
		}



	} else if (c->phys_proc_id == o->phys_proc_id &&

		   c->cpu_die_id == o->cpu_die_id &&

		   c->cpu_core_id == o->cpu_core_id) {

		return topology_sane(c, o, "smt");

	}

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