[patch 5/6] x86/idle: Let prefer_mwait_c1_over_halt() return bool

From: Thomas Gleixner
Date: Thu Feb 29 2024 - 09:25:02 EST


The return value is truly boolean. Make it so.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
arch/x86/kernel/process.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -853,21 +853,21 @@ void __noreturn stop_this_cpu(void *dumm
* Do not prefer MWAIT if MONITOR instruction has a bug or idle=nomwait
* is passed to kernel commandline parameter.
*/
-static int prefer_mwait_c1_over_halt(const struct cpuinfo_x86 *c)
+static bool prefer_mwait_c1_over_halt(const struct cpuinfo_x86 *c)
{
u32 eax, ebx, ecx, edx;

/* If override is enforced on the command line, fall back to HALT. */
if (boot_option_idle_override != IDLE_NO_OVERRIDE)
- return 0;
+ return false;

/* MWAIT is not supported on this platform. Fallback to HALT */
if (!cpu_has(c, X86_FEATURE_MWAIT))
- return 0;
+ return false;

/* Monitor has a bug or APIC stops in C1E. Fallback to HALT */
if (boot_cpu_has_bug(X86_BUG_MONITOR) || boot_cpu_has_bug(X86_BUG_AMD_APIC_C1E))
- return 0;
+ return false;

cpuid(CPUID_MWAIT_LEAF, &eax, &ebx, &ecx, &edx);

@@ -876,13 +876,13 @@ static int prefer_mwait_c1_over_halt(con
* with EAX=0, ECX=0.
*/
if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED))
- return 1;
+ return true;

/*
* If MWAIT extensions are available, there should be at least one
* MWAIT C1 substate present.
*/
- return (edx & MWAIT_C1_SUBSTATE_MASK);
+ return !!(edx & MWAIT_C1_SUBSTATE_MASK);
}

/*