lkml.org 
[lkml]   [2018]   [Dec]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 2/3] 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 usecase.

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>
---
arch/riscv/include/asm/smp.h | 13 +++++++++++--
arch/riscv/kernel/setup.c | 2 ++
2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/arch/riscv/include/asm/smp.h b/arch/riscv/include/asm/smp.h
index 41aa73b4..8f30300f 100644
--- a/arch/riscv/include/asm/smp.h
+++ b/arch/riscv/include/asm/smp.h
@@ -22,12 +22,13 @@
/*
* 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]

+extern unsigned long boot_cpu_hartid;
struct seq_file;

#ifdef CONFIG_SMP
+extern unsigned long __cpuid_to_hartid_map[NR_CPUS];
+#define cpuid_to_hartid_map(cpu) __cpuid_to_hartid_map[cpu]

/* print IPI stats */
void show_ipi_stats(struct seq_file *p, int prec);
@@ -58,7 +59,15 @@ 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;
+ else
+ 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 2c290e6a..bd4d7b85 100644
--- a/arch/riscv/kernel/setup.c
+++ b/arch/riscv/kernel/setup.c
@@ -83,6 +83,7 @@ EXPORT_SYMBOL(empty_zero_page);
atomic_t hart_lottery;
unsigned long boot_cpu_hartid;

+#ifdef CONFIG_SMP
unsigned long __cpuid_to_hartid_map[NR_CPUS] = {
[0 ... NR_CPUS-1] = INVALID_HARTID
};
@@ -91,6 +92,7 @@ void __init smp_setup_processor_id(void)
{
cpuid_to_hartid_map(0) = boot_cpu_hartid;
}
+#endif

#ifdef CONFIG_BLK_DEV_INITRD
static void __init setup_initrd(void)
--
2.7.4
\
 
 \ /
  Last update: 2018-12-27 00:10    [W:0.062 / U:0.568 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site