From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: [PATCH v3 02/51] x86/idle: Replace x86_idle with a static_call Date: Thu, 12 Jan 2023 20:43:16 +0100 Message-ID: <20230112195539.453613251@infradead.org> References: <20230112194314.845371875@infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: DKIM-Filter: OpenDKIM Filter v2.11.0 smtp4.osuosl.org 8C0244009B DKIM-Filter: OpenDKIM Filter v2.11.0 smtp4.osuosl.org 3AE9641837 DKIM-Filter: OpenDKIM Filter v2.11.0 smtp4.osuosl.org 26BE74182E DKIM-Filter: OpenDKIM Filter v2.11.0 smtp4.osuosl.org AF09F4180F DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=Content-Type:MIME-Version:References: Subject:Cc:To:From:Date:Message-ID:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:In-Reply-To; bh=tPOdw9LFGiPCDTfwXmDjC03yH+Atd2yWpwgqK4SP6Bs=; b=MCFGk/zfAQ1MOxe655CfrxSndB KMsj8OM47QEIEF+dE7LPbkmxg/PQAts31gFJ5Xz3no3m62IuisxdrSXrLN8SYgr1mtDIwtR8p1Foy vgMnbz7h6ch5F50b53yunuqk9MFEuX5uEMORRcRhTqQRFnQzXIgNjlWLrzQ8IyZodgjiEI5j/hfm2 jtsLGmSu2xYww6Em1c+Sd7XPqSMSM0BgTy1Y9iUSaQMsmpIltEMs2Z+FvPcdV8LPGTs0uCR8XY70j Jdml4OVol/2E06Nb6eijodGglka4wn0K9TaSFCWA1YgF/306McxeUsk6Jgniwje3STV7G1K2gesSb SZObcOlw==; List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: virtualization-bounces@lists.linux-foundation.org Sender: "Virtualization" To: peterz@infradead.org Cc: juri.lelli@redhat.com, "Rafael J. Wysocki" , rafael@kernel.org, catalin.marinas@arm.com, linus.walleij@linaro.org, nsekhar@ti.com, bsegall@google.com, guoren@kernel.org, pavel@ucw.cz, agordeev@linux.ibm.com, linux-arch@vger.kernel.org, linux-samsung-soc@vger.kernel.org, vincent.guittot@linaro.org, mpe@ellerman.id.au, chenhuacai@kernel.org, christophe.leroy@csgroup.eu, linux-acpi@vger.kernel.org, agross@kernel.org, geert@linux-m68k.org, linux-imx@nxp.com, vgupta@kernel.org, mattst88@gmail.com, mturquette@baylibre.com, sammy@sammy.net, pmladek@suse.com, linux-pm@vger.kernel.org, Sascha Hauer , linux-um@lists.infradead.org, npiggin@gmail.com, tglx@linutronix.de, linux-omap@vger.kernel.org, dietmar.eggemann@arm.com, andreyknvl@gmail.com, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel. Typical boot time setup; no need to suffer an indirect call for that. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Frederic Weisbecker Reviewed-by: Rafael J. Wysocki Tested-by: Tony Lindgren Tested-by: Ulf Hansson --- arch/x86/kernel/process.c | 50 +++++++++++++++++++++++++--------------------- 1 file changed, 28 insertions(+), 22 deletions(-) --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -24,6 +24,7 @@ #include #include #include +#include #include #include #include @@ -692,7 +693,23 @@ void __switch_to_xtra(struct task_struct 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) @@ -715,28 +732,17 @@ 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; } @@ -859,20 +865,20 @@ void select_idle_routine(const struct cp 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) @@ -925,7 +931,7 @@ 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")) { /*