diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2023-01-12 20:43:16 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2023-01-13 11:03:21 +0100 |
| commit | aaa3896b969bdf946e0fd6aa6199da17b5da8d5c (patch) | |
| tree | bb31f436d3d9622cbf96bc09322f2ed22903e59e /arch/x86/kernel/process.c | |
| parent | 1f7c232ee080f01ded1236685a357f8926e8c7d5 (diff) | |
x86/idle: Replace 'x86_idle' function pointer with a static_call
Typical boot time setup; no need to suffer an indirect call for that.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/20230112195539.453613251@infradead.org
Diffstat (limited to 'arch/x86/kernel/process.c')
| -rw-r--r-- | arch/x86/kernel/process.c | 50 |
1 files changed, 28 insertions, 22 deletions
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index 40d156a31676..8481fbefe282 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -24,6 +24,7 @@ #include <linux/cpuidle.h> #include <linux/acpi.h> #include <linux/elf-randomize.h> +#include <linux/static_call.h> #include <trace/events/power.h> #include <linux/hw_breakpoint.h> #include <asm/cpu.h> @@ -694,7 +695,23 @@ void __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p) unsigned long boot_option_idle_override = IDLE_NO_OVERRIDE; EXPORT_SYMBOL(boot_option_idle_override); -static void (*x86_idle)(void); +/* + * We use this if we don't have any better idle routine.. + */ +void __cpuidle default_idle(void) +{ + raw_safe_halt(); +} +#if defined(CONFIG_APM_MODULE) || defined(CONFIG_HALTPOLL_CPUIDLE_MODULE) +EXPORT_SYMBOL(default_idle); +#endif + +DEFINE_STATIC_CALL_NULL(x86_idle, default_idle); + +static bool x86_idle_set(void) +{ + return !!static_call_query(x86_idle); +} #ifndef CONFIG_SMP static inline void play_dead(void) @@ -717,28 +734,17 @@ void arch_cpu_idle_dead(void) /* * Called from the generic idle code. */ -void arch_cpu_idle(void) -{ - x86_idle(); -} - -/* - * We use this if we don't have any better idle routine.. - */ -void __cpuidle default_idle(void) +void __cpuidle arch_cpu_idle(void) { - raw_safe_halt(); + static_call(x86_idle)(); } -#if defined(CONFIG_APM_MODULE) || defined(CONFIG_HALTPOLL_CPUIDLE_MODULE) -EXPORT_SYMBOL(default_idle); -#endif #ifdef CONFIG_XEN bool xen_set_default_idle(void) { - bool ret = !!x86_idle; + bool ret = x86_idle_set(); - x86_idle = default_idle; + static_call_update(x86_idle, default_idle); return ret; } @@ -880,20 +886,20 @@ void select_idle_routine(const struct cpuinfo_x86 *c) if (boot_option_idle_override == IDLE_POLL && smp_num_siblings > 1) pr_warn_once("WARNING: polling idle and HT enabled, performance may degrade\n"); #endif - if (x86_idle || boot_option_idle_override == IDLE_POLL) + if (x86_idle_set() || boot_option_idle_override == IDLE_POLL) return; if (boot_cpu_has_bug(X86_BUG_AMD_E400)) { pr_info("using AMD E400 aware idle routine\n"); - x86_idle = amd_e400_idle; + static_call_update(x86_idle, amd_e400_idle); } else if (prefer_mwait_c1_over_halt(c)) { pr_info("using mwait in idle threads\n"); - x86_idle = mwait_idle; + static_call_update(x86_idle, mwait_idle); } else if (cpu_feature_enabled(X86_FEATURE_TDX_GUEST)) { pr_info("using TDX aware idle routine\n"); - x86_idle = tdx_safe_halt; + static_call_update(x86_idle, tdx_safe_halt); } else - x86_idle = default_idle; + static_call_update(x86_idle, default_idle); } void amd_e400_c1e_apic_setup(void) @@ -946,7 +952,7 @@ static int __init idle_setup(char *str) * To continue to load the CPU idle driver, don't touch * the boot_option_idle_override. */ - x86_idle = default_idle; + static_call_update(x86_idle, default_idle); boot_option_idle_override = IDLE_HALT; } else if (!strcmp(str, "nomwait")) { /* |