[2/3] riscv: Remove unused members from struct cpu_operations
Commit Message
name is not used anywhere at all. cpu_prepare and cpu_disable do nothing
and always return 0 if implemented.
Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
---
arch/riscv/include/asm/cpu_ops.h | 10 ----------
arch/riscv/kernel/cpu-hotplug.c | 9 +--------
arch/riscv/kernel/cpu_ops.c | 2 --
arch/riscv/kernel/cpu_ops_sbi.c | 19 -------------------
arch/riscv/kernel/cpu_ops_spinwait.c | 11 -----------
arch/riscv/kernel/head.S | 1 -
arch/riscv/kernel/setup.c | 1 -
arch/riscv/kernel/smpboot.c | 6 ------
8 files changed, 1 insertion(+), 58 deletions(-)
Comments
On Tue, Nov 21, 2023 at 03:47:25PM -0800, Samuel Holland wrote:
> name is not used anywhere at all. cpu_prepare and cpu_disable do nothing
> and always return 0 if implemented.
>
> Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Part of me says this should be split so that it can be partially
reverted whenever we grow users for these, but I doubt that the
implementer of that will notice nor that anyone will remember you
removed them. Certainly wouldn't object if there was a split though.
I guess in general this was a case of copy-pasting stuff from arm64
that we did not yet have users for.
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Cheers,
Conor.
@@ -13,26 +13,16 @@
/**
* struct cpu_operations - Callback operations for hotplugging CPUs.
*
- * @name: Name of the boot protocol.
- * @cpu_prepare: Early one-time preparation step for a cpu. If there
- * is a mechanism for doing so, tests whether it is
- * possible to boot the given HART.
* @cpu_start: Boots a cpu into the kernel.
- * @cpu_disable: Prepares a cpu to die. May fail for some
- * mechanism-specific reason, which will cause the hot
- * unplug to be aborted. Called from the cpu to be killed.
* @cpu_stop: Makes a cpu leave the kernel. Must not fail. Called from
* the cpu being stopped.
* @cpu_is_stopped: Ensures a cpu has left the kernel. Called from another
* cpu.
*/
struct cpu_operations {
- const char *name;
- int (*cpu_prepare)(unsigned int cpu);
int (*cpu_start)(unsigned int cpu,
struct task_struct *tidle);
#ifdef CONFIG_HOTPLUG_CPU
- int (*cpu_disable)(unsigned int cpu);
void (*cpu_stop)(void);
int (*cpu_is_stopped)(unsigned int cpu);
#endif
@@ -29,25 +29,18 @@ bool cpu_has_hotplug(unsigned int cpu)
*/
int __cpu_disable(void)
{
- int ret = 0;
unsigned int cpu = smp_processor_id();
if (!cpu_ops[cpu] || !cpu_ops[cpu]->cpu_stop)
return -EOPNOTSUPP;
- if (cpu_ops[cpu]->cpu_disable)
- ret = cpu_ops[cpu]->cpu_disable(cpu);
-
- if (ret)
- return ret;
-
remove_cpu_topology(cpu);
numa_remove_cpu(cpu);
set_cpu_online(cpu, false);
riscv_ipi_disable();
irq_migrate_all_off_this_cpu();
- return ret;
+ return 0;
}
#ifdef CONFIG_HOTPLUG_CPU
@@ -18,8 +18,6 @@ const struct cpu_operations *cpu_ops[NR_CPUS] __ro_after_init;
extern const struct cpu_operations cpu_ops_sbi;
#ifndef CONFIG_RISCV_BOOT_SPINWAIT
const struct cpu_operations cpu_ops_spinwait = {
- .name = "",
- .cpu_prepare = NULL,
.cpu_start = NULL,
};
#endif
@@ -79,23 +79,7 @@ static int sbi_cpu_start(unsigned int cpuid, struct task_struct *tidle)
return sbi_hsm_hart_start(hartid, boot_addr, hsm_data);
}
-static int sbi_cpu_prepare(unsigned int cpuid)
-{
- if (!cpu_ops_sbi.cpu_start) {
- pr_err("cpu start method not defined for CPU [%d]\n", cpuid);
- return -ENODEV;
- }
- return 0;
-}
-
#ifdef CONFIG_HOTPLUG_CPU
-static int sbi_cpu_disable(unsigned int cpuid)
-{
- if (!cpu_ops_sbi.cpu_stop)
- return -EOPNOTSUPP;
- return 0;
-}
-
static void sbi_cpu_stop(void)
{
int ret;
@@ -118,11 +102,8 @@ static int sbi_cpu_is_stopped(unsigned int cpuid)
#endif
const struct cpu_operations cpu_ops_sbi = {
- .name = "sbi",
- .cpu_prepare = sbi_cpu_prepare,
.cpu_start = sbi_cpu_start,
#ifdef CONFIG_HOTPLUG_CPU
- .cpu_disable = sbi_cpu_disable,
.cpu_stop = sbi_cpu_stop,
.cpu_is_stopped = sbi_cpu_is_stopped,
#endif
@@ -39,15 +39,6 @@ static void cpu_update_secondary_bootdata(unsigned int cpuid,
WRITE_ONCE(__cpu_spinwait_task_pointer[hartid], tidle);
}
-static int spinwait_cpu_prepare(unsigned int cpuid)
-{
- if (!cpu_ops_spinwait.cpu_start) {
- pr_err("cpu start method not defined for CPU [%d]\n", cpuid);
- return -ENODEV;
- }
- return 0;
-}
-
static int spinwait_cpu_start(unsigned int cpuid, struct task_struct *tidle)
{
/*
@@ -64,7 +55,5 @@ static int spinwait_cpu_start(unsigned int cpuid, struct task_struct *tidle)
}
const struct cpu_operations cpu_ops_spinwait = {
- .name = "spinwait",
- .cpu_prepare = spinwait_cpu_prepare,
.cpu_start = spinwait_cpu_start,
};
@@ -11,7 +11,6 @@
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/csr.h>
-#include <asm/cpu_ops_sbi.h>
#include <asm/hwcap.h>
#include <asm/image.h>
#include <asm/scs.h>
@@ -26,7 +26,6 @@
#include <asm/alternative.h>
#include <asm/cacheflush.h>
#include <asm/cpufeature.h>
-#include <asm/cpu_ops.h>
#include <asm/early_ioremap.h>
#include <asm/pgtable.h>
#include <asm/setup.h>
@@ -49,7 +49,6 @@ void __init smp_prepare_boot_cpu(void)
void __init smp_prepare_cpus(unsigned int max_cpus)
{
int cpuid;
- int ret;
unsigned int curr_cpuid;
init_cpu_topology();
@@ -66,11 +65,6 @@ void __init smp_prepare_cpus(unsigned int max_cpus)
for_each_possible_cpu(cpuid) {
if (cpuid == curr_cpuid)
continue;
- if (cpu_ops[cpuid]->cpu_prepare) {
- ret = cpu_ops[cpuid]->cpu_prepare(cpuid);
- if (ret)
- continue;
- }
set_cpu_present(cpuid, true);
numa_store_cpu_info(cpuid);
}