[patch 2/9] x86/msr: Prepare for including percpu.h

From: Thomas Gleixner
Date: Mon Mar 04 2024 - 05:14:18 EST


To cleanup the per CPU insanity of UP which causes sparse to be rightfully
unhappy and prevents the usage of the generic per cpu accessors on cpu_info
it is necessary to include linux/percpu.h into asm/msr.h.

Including percpu.h into msr.h is impossible because it ends up in header
dependency hell. The problem is that processor.h includes msr.h. The
inclusion of percpu.h results in a compile fail where the compiler cannot
longer handle an include in cpufeature.h which references boot_cpu_data
which is defined in processor.h

The only reason why msr.h is included in processor.h are the
set/get_debugctlmsr() inlines. They are defined there because processor.h
is such a nice dump ground for everything. In fact they belong obviously
into debugreg.h.

Move them to debugreg.h and fixup the resulting damage which is just
exposing the reliance on random include chains.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
arch/x86/events/intel/core.c | 1 +
arch/x86/events/intel/ds.c | 1 +
arch/x86/include/asm/debugreg.h | 24 ++++++++++++++++++++++++
arch/x86/include/asm/fsgsbase.h | 2 +-
arch/x86/include/asm/processor.h | 22 ----------------------
arch/x86/include/asm/special_insns.h | 4 ++--
arch/x86/kernel/cpu/intel_pconfig.c | 2 ++
arch/x86/kernel/cpu/rdrand.c | 1 +
arch/x86/kernel/fpu/bugs.c | 2 ++
arch/x86/kernel/step.c | 2 ++
10 files changed, 36 insertions(+), 25 deletions(-)

--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -17,6 +17,7 @@
#include <linux/kvm_host.h>

#include <asm/cpufeature.h>
+#include <asm/debugreg.h>
#include <asm/hardirq.h>
#include <asm/intel-family.h>
#include <asm/intel_pt.h>
--- a/arch/x86/events/intel/ds.c
+++ b/arch/x86/events/intel/ds.c
@@ -5,6 +5,7 @@
#include <linux/sched/clock.h>

#include <asm/cpu_entry_area.h>
+#include <asm/debugreg.h>
#include <asm/perf_event.h>
#include <asm/tlbflush.h>
#include <asm/insn.h>
--- a/arch/x86/include/asm/debugreg.h
+++ b/arch/x86/include/asm/debugreg.h
@@ -5,7 +5,9 @@
#include <linux/bug.h>
#include <linux/percpu.h>
#include <uapi/asm/debugreg.h>
+
#include <asm/cpufeature.h>
+#include <asm/msr.h>

DECLARE_PER_CPU(unsigned long, cpu_dr7);

@@ -159,4 +161,26 @@ static inline unsigned long amd_get_dr_a
}
#endif

+static inline unsigned long get_debugctlmsr(void)
+{
+ unsigned long debugctlmsr = 0;
+
+#ifndef CONFIG_X86_DEBUGCTLMSR
+ if (boot_cpu_data.x86 < 6)
+ return 0;
+#endif
+ rdmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
+
+ return debugctlmsr;
+}
+
+static inline void update_debugctlmsr(unsigned long debugctlmsr)
+{
+#ifndef CONFIG_X86_DEBUGCTLMSR
+ if (boot_cpu_data.x86 < 6)
+ return;
+#endif
+ wrmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
+}
+
#endif /* _ASM_X86_DEBUGREG_H */
--- a/arch/x86/include/asm/fsgsbase.h
+++ b/arch/x86/include/asm/fsgsbase.h
@@ -6,7 +6,7 @@

#ifdef CONFIG_X86_64

-#include <asm/msr-index.h>
+#include <asm/msr.h>

/*
* Read/write a task's FSBASE or GSBASE. This returns the value that
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -578,28 +578,6 @@ extern void cpu_init(void);
extern void cpu_init_exception_handling(void);
extern void cr4_init(void);

-static inline unsigned long get_debugctlmsr(void)
-{
- unsigned long debugctlmsr = 0;
-
-#ifndef CONFIG_X86_DEBUGCTLMSR
- if (boot_cpu_data.x86 < 6)
- return 0;
-#endif
- rdmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
-
- return debugctlmsr;
-}
-
-static inline void update_debugctlmsr(unsigned long debugctlmsr)
-{
-#ifndef CONFIG_X86_DEBUGCTLMSR
- if (boot_cpu_data.x86 < 6)
- return;
-#endif
- wrmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
-}
-
extern void set_task_blockstep(struct task_struct *task, bool on);

/* Boot loader type from the setup header: */
--- a/arch/x86/include/asm/special_insns.h
+++ b/arch/x86/include/asm/special_insns.h
@@ -2,11 +2,11 @@
#ifndef _ASM_X86_SPECIAL_INSNS_H
#define _ASM_X86_SPECIAL_INSNS_H

-
#ifdef __KERNEL__
-
#include <asm/nops.h>
#include <asm/processor-flags.h>
+
+#include <linux/errno.h>
#include <linux/irqflags.h>
#include <linux/jump_label.h>

--- a/arch/x86/kernel/cpu/intel_pconfig.c
+++ b/arch/x86/kernel/cpu/intel_pconfig.c
@@ -7,6 +7,8 @@
* Author:
* Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
*/
+#include <linux/bug.h>
+#include <linux/limits.h>

#include <asm/cpufeature.h>
#include <asm/intel_pconfig.h>
--- a/arch/x86/kernel/cpu/rdrand.c
+++ b/arch/x86/kernel/cpu/rdrand.c
@@ -6,6 +6,7 @@
* Authors: Fenghua Yu <fenghua.yu@xxxxxxxxx>,
* H. Peter Anvin <hpa@xxxxxxxxxxxxxxx>
*/
+#include <linux/printk.h>

#include <asm/processor.h>
#include <asm/archrandom.h>
--- a/arch/x86/kernel/fpu/bugs.c
+++ b/arch/x86/kernel/fpu/bugs.c
@@ -2,6 +2,8 @@
/*
* x86 FPU bug checks:
*/
+#include <linux/printk.h>
+
#include <asm/cpufeature.h>
#include <asm/fpu/api.h>

--- a/arch/x86/kernel/step.c
+++ b/arch/x86/kernel/step.c
@@ -6,7 +6,9 @@
#include <linux/sched/task_stack.h>
#include <linux/mm.h>
#include <linux/ptrace.h>
+
#include <asm/desc.h>
+#include <asm/debugreg.h>
#include <asm/mmu_context.h>

unsigned long convert_ip_to_linear(struct task_struct *child, struct pt_regs *regs)