[patch 3/9] x86/msr: Add missing __percpu annotations

Thomas Gleixner
2024-03-04T10:12:22Z

sparse complains rightfully about using a plain pointer for per CPU
accessors:

msr-smp.c:15:23: sparse: warning: incorrect type in initializer (different address spaces)
msr-smp.c:15:23: sparse: expected void const [noderef] __percpu *__vpp_verify
msr-smp.c:15:23: sparse: got struct msr *

Add __percpu annotations to the related datastructure and function
arguments to cure this. This also cures the related sparse warnings at the
callsites in drivers/edac/amd64_edac.c.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
arch/x86/include/asm/msr.h | 26 ++++++++++++++------------
arch/x86/include/asm/processor.h | 1 -
arch/x86/include/asm/tsc.h | 3 ++-
arch/x86/lib/msr-smp.c | 12 +++++-------
arch/x86/lib/msr.c | 6 +++---
5 files changed, 24 insertions(+), 24 deletions(-)

--- a/arch/x86/include/asm/msr.h
+++ b/arch/x86/include/asm/msr.h
@@ -12,11 +12,13 @@
#include <uapi/asm/msr.h>
#include <asm/shared/msr.h>

+#include <linux/percpu.h>
+
struct msr_info {
- u32 msr_no;
- struct msr reg;
- struct msr *msrs;
- int err;
+ u32 msr_no;
+ struct msr reg;
+ struct msr __percpu *msrs;
+ int err;
};

struct msr_regs_info {
@@ -323,8 +325,8 @@ static inline int wrmsrl_safe(u32 msr, u
return wrmsr_safe(msr, (u32)val, (u32)(val >> 32));
}

-struct msr *msrs_alloc(void);
-void msrs_free(struct msr *msrs);
+struct msr __percpu *msrs_alloc(void);
+void msrs_free(struct msr __percpu *msrs);
int msr_set_bit(u32 msr, u8 bit);
int msr_clear_bit(u32 msr, u8 bit);

@@ -333,8 +335,8 @@ int rdmsr_on_cpu(unsigned int cpu, u32 m
int wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h);
int rdmsrl_on_cpu(unsigned int cpu, u32 msr_no, u64 *q);
int wrmsrl_on_cpu(unsigned int cpu, u32 msr_no, u64 q);
-void rdmsr_on_cpus(const struct cpumask *mask, u32 msr_no, struct msr *msrs);
-void wrmsr_on_cpus(const struct cpumask *mask, u32 msr_no, struct msr *msrs);
+void rdmsr_on_cpus(const struct cpumask *mask, u32 msr_no, struct msr __percpu *msrs);
+void wrmsr_on_cpus(const struct cpumask *mask, u32 msr_no, struct msr __percpu *msrs);
int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h);
int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h);
int rdmsrl_safe_on_cpu(unsigned int cpu, u32 msr_no, u64 *q);
@@ -363,14 +365,14 @@ static inline int wrmsrl_on_cpu(unsigned
return 0;
}
static inline void rdmsr_on_cpus(const struct cpumask *m, u32 msr_no,
- struct msr *msrs)
+ struct msr __percpu *msrs)
{
- rdmsr_on_cpu(0, msr_no, &(msrs[0].l), &(msrs[0].h));
+ rdmsr_on_cpu(0, msr_no, raw_cpu_ptr(&msrs->l), raw_cpu_ptr(&msrs->h));
}
static inline void wrmsr_on_cpus(const struct cpumask *m, u32 msr_no,
- struct msr *msrs)
+ struct msr __percpu *msrs)
{
- wrmsr_on_cpu(0, msr_no, msrs[0].l, msrs[0].h);
+ wrmsr_on_cpu(0, msr_no, raw_cpu_read(msrs->l), raw_cpu_read(msrs->h));
}
static inline int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no,
u32 *l, u32 *h)
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -20,7 +20,6 @@ struct vm86;
#include <asm/page.h>
#include <asm/pgtable_types.h>
#include <asm/percpu.h>
-#include <asm/msr.h>
#include <asm/desc_defs.h>
#include <asm/nops.h>
#include <asm/special_insns.h>
--- a/arch/x86/include/asm/tsc.h
+++ b/arch/x86/include/asm/tsc.h
@@ -5,8 +5,9 @@
#ifndef _ASM_X86_TSC_H
#define _ASM_X86_TSC_H

-#include <asm/processor.h>
#include <asm/cpufeature.h>
+#include <asm/processor.h>
+#include <asm/msr.h>

/*
* Standard way to access the cycle counter.
--- a/arch/x86/lib/msr-smp.c
+++ b/arch/x86/lib/msr-smp.c
@@ -9,10 +9,9 @@ static void __rdmsr_on_cpu(void *info)
{
struct msr_info *rv = info;
struct msr *reg;
- int this_cpu = raw_smp_processor_id();

if (rv->msrs)
- reg = per_cpu_ptr(rv->msrs, this_cpu);
+ reg = this_cpu_ptr(rv->msrs);
else
reg = &rv->reg;

@@ -23,10 +22,9 @@ static void __wrmsr_on_cpu(void *info)
{
struct msr_info *rv = info;
struct msr *reg;
- int this_cpu = raw_smp_processor_id();

if (rv->msrs)
- reg = per_cpu_ptr(rv->msrs, this_cpu);
+ reg = this_cpu_ptr(rv->msrs);
else
reg = &rv->reg;

@@ -97,7 +95,7 @@ int wrmsrl_on_cpu(unsigned int cpu, u32
EXPORT_SYMBOL(wrmsrl_on_cpu);

static void __rwmsr_on_cpus(const struct cpumask *mask, u32 msr_no,
- struct msr *msrs,
+ struct msr __percpu *msrs,
void (*msr_func) (void *info))
{
struct msr_info rv;
@@ -124,7 +122,7 @@ static void __rwmsr_on_cpus(const struct
* @msrs: array of MSR values
*
*/
-void rdmsr_on_cpus(const struct cpumask *mask, u32 msr_no, struct msr *msrs)
+void rdmsr_on_cpus(const struct cpumask *mask, u32 msr_no, struct msr __percpu *msrs)
{
__rwmsr_on_cpus(mask, msr_no, msrs, __rdmsr_on_cpu);
}
@@ -138,7 +136,7 @@ EXPORT_SYMBOL(rdmsr_on_cpus);
* @msrs: array of MSR values
*
*/
-void wrmsr_on_cpus(const struct cpumask *mask, u32 msr_no, struct msr *msrs)
+void wrmsr_on_cpus(const struct cpumask *mask, u32 msr_no, struct msr __percpu *msrs)
{
__rwmsr_on_cpus(mask, msr_no, msrs, __wrmsr_on_cpu);
}
--- a/arch/x86/lib/msr.c
+++ b/arch/x86/lib/msr.c
@@ -6,9 +6,9 @@
#define CREATE_TRACE_POINTS
#include <asm/msr-trace.h>

-struct msr *msrs_alloc(void)
+struct msr __percpu *msrs_alloc(void)
{
- struct msr *msrs = NULL;
+ struct msr __percpu *msrs = NULL;

msrs = alloc_percpu(struct msr);
if (!msrs) {
@@ -20,7 +20,7 @@ struct msr *msrs_alloc(void)
}
EXPORT_SYMBOL(msrs_alloc);

-void msrs_free(struct msr *msrs)
+void msrs_free(struct msr __percpu *msrs)
{
free_percpu(msrs);
}