Commit 519be7da authored by Xin Li (Intel)'s avatar Xin Li (Intel) Committed by Ingo Molnar
Browse files

x86/msr: Convert __wrmsr() uses to native_wrmsr{,q}() uses 



__wrmsr() is the lowest level MSR write API, with native_wrmsr()
and native_wrmsrq() serving as higher-level wrappers around it:

  #define native_wrmsr(msr, low, high)                    \
          __wrmsr(msr, low, high)

  #define native_wrmsrl(msr, val)                         \
          __wrmsr((msr), (u32)((u64)(val)),               \
                         (u32)((u64)(val) >> 32))

However, __wrmsr() continues to be utilized in various locations.

MSR APIs are designed for different scenarios, such as native or
pvops, with or without trace, and safe or non-safe.  Unfortunately,
the current MSR API names do not adequately reflect these factors,
making it challenging to select the most appropriate API for
various situations.

To pave the way for improving MSR API names, convert __wrmsr()
uses to native_wrmsr{,q}() to ensure consistent usage.  Later,
these APIs can be renamed to better reflect their implications,
such as native or pvops, with or without trace, and safe or
non-safe.

No functional change intended.

Signed-off-by: default avatarXin Li (Intel) <xin@zytor.com>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
Acked-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Uros Bizjak <ubizjak@gmail.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20250427092027.1598740-8-xin@zytor.com
parent 5afa4cf5

arch/x86/events/amd/brs.c

+1 −1
Original line number Diff line number Diff line
@@ -44,7 +44,7 @@ static inline unsigned int brs_to(int idx) 
static __always_inline void set_debug_extn_cfg(u64 val)

{

	/* bits[4:3] must always be set to 11b */

	__wrmsr(MSR_AMD_DBG_EXTN_CFG, val | 3ULL << 3, val >> 32);

	native_wrmsrq(MSR_AMD_DBG_EXTN_CFG, val | 3ULL << 3);

}



static __always_inline u64 get_debug_extn_cfg(void)

arch/x86/include/asm/apic.h

+1 −1
Original line number Diff line number Diff line
@@ -214,7 +214,7 @@ static inline void native_apic_msr_write(u32 reg, u32 v) 


static inline void native_apic_msr_eoi(void)

{

	__wrmsr(APIC_BASE_MSR + (APIC_EOI >> 4), APIC_EOI_ACK, 0);

	native_wrmsrq(APIC_BASE_MSR + (APIC_EOI >> 4), APIC_EOI_ACK);

}



static inline u32 native_apic_msr_read(u32 reg)

arch/x86/include/asm/msr.h

+4 −2
Original line number Diff line number Diff line
@@ -127,10 +127,12 @@ static inline u64 native_read_msr_safe(u32 msr, int *err) 
static inline void notrace

native_write_msr(u32 msr, u32 low, u32 high)

{

	__wrmsr(msr, low, high);

	u64 val = (u64)high << 32 | low;



	native_wrmsrq(msr, val);



	if (tracepoint_enabled(write_msr))

		do_trace_write_msr(msr, ((u64)high << 32 | low), 0);

		do_trace_write_msr(msr, val, 0);

}



/* Can be uninlined because referenced by paravirt */

arch/x86/kernel/cpu/mce/core.c

+1 −1
Original line number Diff line number Diff line
@@ -1306,7 +1306,7 @@ static noinstr bool mce_check_crashing_cpu(void) 
		}



		if (mcgstatus & MCG_STATUS_RIPV) {

			__wrmsr(MSR_IA32_MCG_STATUS, 0, 0);

			native_wrmsrq(MSR_IA32_MCG_STATUS, 0);

			return true;

		}

	}

arch/x86/kernel/cpu/resctrl/pseudo_lock.c

+3 −3
Original line number Diff line number Diff line
@@ -483,7 +483,7 @@ int resctrl_arch_pseudo_lock_fn(void *_plr) 
	 * cache.

	 */

	saved_msr = __rdmsr(MSR_MISC_FEATURE_CONTROL);

	__wrmsr(MSR_MISC_FEATURE_CONTROL, prefetch_disable_bits, 0x0);

	native_wrmsrq(MSR_MISC_FEATURE_CONTROL, prefetch_disable_bits);

	closid_p = this_cpu_read(pqr_state.cur_closid);

	rmid_p = this_cpu_read(pqr_state.cur_rmid);

	mem_r = plr->kmem;
@@ -495,7 +495,7 @@ int resctrl_arch_pseudo_lock_fn(void *_plr) 
	 * pseudo-locked followed by reading of kernel memory to load it

	 * into the cache.

	 */

	__wrmsr(MSR_IA32_PQR_ASSOC, rmid_p, plr->closid);

	native_wrmsr(MSR_IA32_PQR_ASSOC, rmid_p, plr->closid);



	/*

	 * Cache was flushed earlier. Now access kernel memory to read it
@@ -532,7 +532,7 @@ int resctrl_arch_pseudo_lock_fn(void *_plr) 
	 * Critical section end: restore closid with capacity bitmask that

	 * does not overlap with pseudo-locked region.

	 */

	__wrmsr(MSR_IA32_PQR_ASSOC, rmid_p, closid_p);

	native_wrmsr(MSR_IA32_PQR_ASSOC, rmid_p, closid_p);



	/* Re-enable the hardware prefetcher(s) */

	wrmsrq(MSR_MISC_FEATURE_CONTROL, saved_msr);