Commit 4fb7d087 authored by Mike Travis's avatar Mike Travis Committed by Ingo Molnar
Browse files

x86/platform/uv: Account for UV Hubless in is_uvX_hub Ops 



The references in the is_uvX_hub() function uses the hub_info pointer
which will be NULL when the system is hubless.  This change avoids
that NULL dereference.  It is also an optimization in performance.

Signed-off-by: default avatarMike Travis <mike.travis@hpe.com>
Reviewed-by: default avatarSteve Wahl <steve.wahl@hpe.com>
Reviewed-by: default avatarDimitri Sivanich <dimitri.sivanich@hpe.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hedi Berriche <hedi.berriche@hpe.com>
Cc: Justin Ernst <justin.ernst@hpe.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russ Anderson <russ.anderson@hpe.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190910145840.294981941@stormcage.eag.rdlabs.hpecorp.net


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent df55029f

arch/x86/include/asm/uv/uv_hub.h

+20 −41
Original line number Diff line number Diff line
@@ -19,6 +19,7 @@ 
#include <linux/topology.h>

#include <asm/types.h>

#include <asm/percpu.h>

#include <asm/uv/uv.h>

#include <asm/uv/uv_mmrs.h>

#include <asm/uv/bios.h>

#include <asm/irq_vectors.h>
@@ -243,83 +244,61 @@ static inline int uv_hub_info_check(int version) 
#define UV4_HUB_REVISION_BASE		7

#define UV4A_HUB_REVISION_BASE		8	/* UV4 (fixed) rev 2 */



#ifdef	UV1_HUB_IS_SUPPORTED

/* WARNING: UVx_HUB_IS_SUPPORTED defines are deprecated and will be removed */

static inline int is_uv1_hub(void)

{

	return uv_hub_info->hub_revision < UV2_HUB_REVISION_BASE;

}

#ifdef	UV1_HUB_IS_SUPPORTED

	return is_uv_hubbed(uv(1));

#else

static inline int is_uv1_hub(void)

{

	return 0;

}

#endif

}



#ifdef	UV2_HUB_IS_SUPPORTED

static inline int is_uv2_hub(void)

{

	return ((uv_hub_info->hub_revision >= UV2_HUB_REVISION_BASE) &&

		(uv_hub_info->hub_revision < UV3_HUB_REVISION_BASE));

}

#ifdef	UV2_HUB_IS_SUPPORTED

	return is_uv_hubbed(uv(2));

#else

static inline int is_uv2_hub(void)

{

	return 0;

}

#endif

}



#ifdef	UV3_HUB_IS_SUPPORTED

static inline int is_uv3_hub(void)

{

	return ((uv_hub_info->hub_revision >= UV3_HUB_REVISION_BASE) &&

		(uv_hub_info->hub_revision < UV4_HUB_REVISION_BASE));

}

#ifdef	UV3_HUB_IS_SUPPORTED

	return is_uv_hubbed(uv(3));

#else

static inline int is_uv3_hub(void)

{

	return 0;

}

#endif

}



/* First test "is UV4A", then "is UV4" */

#ifdef	UV4A_HUB_IS_SUPPORTED

static inline int is_uv4a_hub(void)

{

	return (uv_hub_info->hub_revision >= UV4A_HUB_REVISION_BASE);

}

#else

static inline int is_uv4a_hub(void)

{

#ifdef	UV4A_HUB_IS_SUPPORTED

	if (is_uv_hubbed(uv(4)))

		return (uv_hub_info->hub_revision == UV4A_HUB_REVISION_BASE);

#endif

	return 0;

}

#endif



#ifdef	UV4_HUB_IS_SUPPORTED

static inline int is_uv4_hub(void)

{

	return uv_hub_info->hub_revision >= UV4_HUB_REVISION_BASE;

}

#ifdef	UV4_HUB_IS_SUPPORTED

	return is_uv_hubbed(uv(4));

#else

static inline int is_uv4_hub(void)

{

	return 0;

}

#endif

}



static inline int is_uvx_hub(void)

{

	if (uv_hub_info->hub_revision >= UV2_HUB_REVISION_BASE)

		return uv_hub_info->hub_revision;



	return 0;

	return (is_uv_hubbed(-2) >= uv(2));

}



static inline int is_uv_hub(void)

{

#ifdef	UV1_HUB_IS_SUPPORTED

	return uv_hub_info->hub_revision;

#endif

	return is_uvx_hub();

	return is_uv1_hub() || is_uvx_hub();

}



union uvh_apicid {

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