lkml.org 
[lkml]   [2019]   [Feb]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[v4 PATCH 2/8] RISC-V: Move cpuid to hartid mapping to SMP.
Date
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: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
arch/riscv/include/asm/smp.h | 18 +++++++++++++-----
arch/riscv/kernel/setup.c | 9 ---------
arch/riscv/kernel/smp.c | 9 +++++++++
3 files changed, 22 insertions(+), 14 deletions(-)

diff --git a/arch/riscv/include/asm/smp.h b/arch/riscv/include/asm/smp.h
index 41aa73b4..636a934f 100644
--- a/arch/riscv/include/asm/smp.h
+++ b/arch/riscv/include/asm/smp.h
@@ -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)
{
- return 0;
+ 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,
diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
index fb09e013..61c81616 100644
--- a/arch/riscv/kernel/setup.c
+++ b/arch/riscv/kernel/setup.c
@@ -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)
{
diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c
index 246635ea..b69883c6 100644
--- a/arch/riscv/kernel/smp.c
+++ b/arch/riscv/kernel/smp.c
@@ -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;
--
2.7.4
\
 
 \ /
  Last update: 2019-02-12 12:11    [W:0.086 / U:0.424 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site