[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20230112195539.453613251@infradead.org>
Date: Thu, 12 Jan 2023 20:43:16 +0100
From: Peter Zijlstra <peterz@...radead.org>
To: peterz@...radead.org
Cc: richard.henderson@...aro.org, ink@...assic.park.msu.ru,
mattst88@...il.com, vgupta@...nel.org, linux@...linux.org.uk,
nsekhar@...com, brgl@...ev.pl, ulli.kroll@...glemail.com,
linus.walleij@...aro.org, shawnguo@...nel.org,
Sascha Hauer <s.hauer@...gutronix.de>, kernel@...gutronix.de,
festevam@...il.com, linux-imx@....com, tony@...mide.com,
khilman@...nel.org, krzysztof.kozlowski@...aro.org,
alim.akhtar@...sung.com, catalin.marinas@....com, will@...nel.org,
guoren@...nel.org, bcain@...cinc.com, chenhuacai@...nel.org,
kernel@...0n.name, geert@...ux-m68k.org, sammy@...my.net,
monstr@...str.eu, tsbogend@...ha.franken.de, dinguyen@...nel.org,
jonas@...thpole.se, stefan.kristiansson@...nalahti.fi,
shorne@...il.com, James.Bottomley@...senPartnership.com,
deller@....de, mpe@...erman.id.au, npiggin@...il.com,
christophe.leroy@...roup.eu, paul.walmsley@...ive.com,
palmer@...belt.com, aou@...s.berkeley.edu, hca@...ux.ibm.com,
gor@...ux.ibm.com, agordeev@...ux.ibm.com,
borntraeger@...ux.ibm.com, svens@...ux.ibm.com,
ysato@...rs.sourceforge.jp, dalias@...c.org, davem@...emloft.net,
richard@....at, anton.ivanov@...bridgegreys.com,
johannes@...solutions.net, tglx@...utronix.de, mingo@...hat.com,
bp@...en8.de, dave.hansen@...ux.intel.com, x86@...nel.org,
hpa@...or.com, acme@...nel.org, mark.rutland@....com,
alexander.shishkin@...ux.intel.com, jolsa@...nel.org,
namhyung@...nel.org, jgross@...e.com, srivatsa@...il.mit.edu,
amakhalov@...are.com, pv-drivers@...are.com,
boris.ostrovsky@...cle.com, chris@...kel.net, jcmvbkbc@...il.com,
rafael@...nel.org, lenb@...nel.org, pavel@....cz,
gregkh@...uxfoundation.org, mturquette@...libre.com,
sboyd@...nel.org, daniel.lezcano@...aro.org, lpieralisi@...nel.org,
sudeep.holla@....com, agross@...nel.org, andersson@...nel.org,
konrad.dybcio@...aro.org, anup@...infault.org,
thierry.reding@...il.com, jonathanh@...dia.com,
jacob.jun.pan@...ux.intel.com, atishp@...shpatra.org,
Arnd Bergmann <arnd@...db.de>, yury.norov@...il.com,
andriy.shevchenko@...ux.intel.com, linux@...musvillemoes.dk,
dennis@...nel.org, tj@...nel.org, cl@...ux.com,
rostedt@...dmis.org, mhiramat@...nel.org, frederic@...nel.org,
paulmck@...nel.org, pmladek@...e.com, senozhatsky@...omium.org,
john.ogness@...utronix.de, juri.lelli@...hat.com,
vincent.guittot@...aro.org, dietmar.eggemann@....com,
bsegall@...gle.com, mgorman@...e.de, bristot@...hat.com,
vschneid@...hat.com, ryabinin.a.a@...il.com, glider@...gle.com,
andreyknvl@...il.com, dvyukov@...gle.com,
vincenzo.frascino@....com,
Andrew Morton <akpm@...ux-foundation.org>, jpoimboe@...nel.org,
linux-alpha@...r.kernel.org, linux-kernel@...r.kernel.org,
linux-snps-arc@...ts.infradead.org, linux-omap@...r.kernel.org,
linux-samsung-soc@...r.kernel.org, linux-csky@...r.kernel.org,
linux-hexagon@...r.kernel.org, linux-ia64@...r.kernel.org,
loongarch@...ts.linux.dev, linux-m68k@...ts.linux-m68k.org,
linux-mips@...r.kernel.org, openrisc@...ts.librecores.org,
linux-parisc@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org,
linux-riscv@...ts.infradead.org, linux-s390@...r.kernel.org,
linux-sh@...r.kernel.org, sparclinux@...r.kernel.org,
linux-um@...ts.infradead.org, linux-perf-users@...r.kernel.org,
virtualization@...ts.linux-foundation.org,
linux-xtensa@...ux-xtensa.org, linux-acpi@...r.kernel.org,
linux-pm@...r.kernel.org, linux-clk@...r.kernel.org,
linux-arm-msm@...r.kernel.org, linux-tegra@...r.kernel.org,
linux-arch@...r.kernel.org, linux-mm@...ck.org,
linux-trace-kernel@...r.kernel.org, kasan-dev@...glegroups.com,
"Rafael J. Wysocki" <rafael.j.wysocki@...el.com>,
Ulf Hansson <ulf.hansson@...aro.org>
Subject: [PATCH v3 02/51] x86/idle: Replace x86_idle with a static_call
Typical boot time setup; no need to suffer an indirect call for that.
Signed-off-by: Peter Zijlstra (Intel) <peterz@...radead.org>
Reviewed-by: Frederic Weisbecker <frederic@...nel.org>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@...el.com>
Tested-by: Tony Lindgren <tony@...mide.com>
Tested-by: Ulf Hansson <ulf.hansson@...aro.org>
---
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 <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>
@@ -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")) {
/*
Powered by blists - more mailing lists