Unverified Commit 78d1daa3 authored by Atish Patra's avatar Atish Patra Committed by Palmer Dabbelt
Browse files

RISC-V: Move cpuid to hartid mapping to SMP. 



Currently, logical CPU id to physical hartid mapping is defined for both
smp and non-smp configurations. This is not required as we need this
only for smp configuration.  The mapping function can define directly
boot_cpu_hartid for non-smp use case.

The reverse mapping function i.e. hartid to cpuid can be called for any
valid but not booted harts. So it should return default cpu 0 only if it
is a boot hartid.

Signed-off-by: default avatarAtish Patra <atish.patra@wdc.com>
Reviewed-by: default avatarAnup Patel <anup@brainfault.org>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarPalmer Dabbelt <palmer@sifive.com>
parent e15c6e37

arch/riscv/include/asm/smp.h

+13 −5
Original line number Diff line number Diff line
@@ -19,16 +19,17 @@ 
#include <linux/thread_info.h>



#define INVALID_HARTID ULONG_MAX



struct seq_file;

extern unsigned long boot_cpu_hartid;



#ifdef CONFIG_SMP

/*

 * Mapping between linux logical cpu index and hartid.

 */

extern unsigned long __cpuid_to_hartid_map[NR_CPUS];

#define cpuid_to_hartid_map(cpu)    __cpuid_to_hartid_map[cpu]



struct seq_file;



#ifdef CONFIG_SMP



/* print IPI stats */

void show_ipi_stats(struct seq_file *p, int prec);
@@ -58,7 +59,14 @@ static inline void show_ipi_stats(struct seq_file *p, int prec) 


static inline int riscv_hartid_to_cpuid(int hartid)

{

	if (hartid == boot_cpu_hartid)

		return 0;



	return -1;

}

static inline unsigned long cpuid_to_hartid_map(int cpu)

{

	return boot_cpu_hartid;

}



static inline void riscv_cpuid_to_hartid_mask(const struct cpumask *in,

arch/riscv/kernel/setup.c

+0 −9
Original line number Diff line number Diff line
@@ -61,15 +61,6 @@ EXPORT_SYMBOL(empty_zero_page); 
atomic_t hart_lottery;

unsigned long boot_cpu_hartid;



unsigned long __cpuid_to_hartid_map[NR_CPUS] = {

	[0 ... NR_CPUS-1] = INVALID_HARTID

};



void __init smp_setup_processor_id(void)

{

	cpuid_to_hartid_map(0) = boot_cpu_hartid;

}



#ifdef CONFIG_BLK_DEV_INITRD

static void __init setup_initrd(void)

{

arch/riscv/kernel/smp.c

+9 −0
Original line number Diff line number Diff line
@@ -36,6 +36,15 @@ enum ipi_message_type { 
	IPI_MAX

};



unsigned long __cpuid_to_hartid_map[NR_CPUS] = {

	[0 ... NR_CPUS-1] = INVALID_HARTID

};



void __init smp_setup_processor_id(void)

{

	cpuid_to_hartid_map(0) = boot_cpu_hartid;

}



/* A collection of single bit ipi messages.  */

static struct {

	unsigned long stats[IPI_MAX] ____cacheline_aligned;

CRA Git | Maintained and supported by SUSTech CRA and CCSE