From 1ae899e413105aa81068d0282ab6e22974891d74 Mon Sep 17 00:00:00 2001 From: Uros Bizjak Date: Wed, 2 Apr 2025 20:08:05 +0200 Subject: [PATCH] x86/idle: Standardize argument types for MONITOR{,X} and MWAIT{,X} instruction wrappers on 'u32' MONITOR and MONITORX expect 32-bit unsigned integer arguments in the %ecx and %edx registers. MWAIT and MWAITX expect 32-bit usigned int argument in %eax and %ecx registers. Some of the helpers around these instructions in are using too wide types (long), standardize on u32 instead that makes it clear that this is a hardware ABI. [ mingo: Cleaned up the changelog. ] Signed-off-by: Uros Bizjak Signed-off-by: Ingo Molnar Cc: Andy Lutomirski Cc: Brian Gerst Cc: Juergen Gross Cc: Andrew Cooper Cc: Rik van Riel Cc: "H. Peter Anvin" Cc: Peter Zijlstra Cc: Rafael J. Wysocki Cc: Linus Torvalds Link: https://lore.kernel.org/r/20250402180827.3762-1-ubizjak@gmail.com --- arch/x86/include/asm/mwait.h | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) diff --git a/arch/x86/include/asm/mwait.h b/arch/x86/include/asm/mwait.h index 54dc313bcdf01..3377869ff2e8b 100644 --- a/arch/x86/include/asm/mwait.h +++ b/arch/x86/include/asm/mwait.h @@ -25,23 +25,21 @@ #define TPAUSE_C01_STATE 1 #define TPAUSE_C02_STATE 0 -static __always_inline void __monitor(const void *eax, unsigned long ecx, - unsigned long edx) +static __always_inline void __monitor(const void *eax, u32 ecx, u32 edx) { /* "monitor %eax, %ecx, %edx;" */ asm volatile(".byte 0x0f, 0x01, 0xc8;" :: "a" (eax), "c" (ecx), "d"(edx)); } -static __always_inline void __monitorx(const void *eax, unsigned long ecx, - unsigned long edx) +static __always_inline void __monitorx(const void *eax, u32 ecx, u32 edx) { /* "monitorx %eax, %ecx, %edx;" */ asm volatile(".byte 0x0f, 0x01, 0xfa;" :: "a" (eax), "c" (ecx), "d"(edx)); } -static __always_inline void __mwait(unsigned long eax, unsigned long ecx) +static __always_inline void __mwait(u32 eax, u32 ecx) { mds_idle_clear_cpu_buffers(); @@ -76,8 +74,7 @@ static __always_inline void __mwait(unsigned long eax, unsigned long ecx) * EAX (logical) address to monitor * ECX #GP if not zero */ -static __always_inline void __mwaitx(unsigned long eax, unsigned long ebx, - unsigned long ecx) +static __always_inline void __mwaitx(u32 eax, u32 ebx, u32 ecx) { /* No MDS buffer clear as this is AMD/HYGON only */ @@ -95,7 +92,7 @@ static __always_inline void __mwaitx(unsigned long eax, unsigned long ebx, * executing mwait, it would otherwise go unnoticed and the next tick * would not be reprogrammed accordingly before mwait ever wakes up. */ -static __always_inline void __sti_mwait(unsigned long eax, unsigned long ecx) +static __always_inline void __sti_mwait(u32 eax, u32 ecx) { mds_idle_clear_cpu_buffers(); /* "mwait %eax, %ecx;" */ -- 2.39.5