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Bottomley" , Helge Deller , Scott Wood , Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , "Christophe Leroy (CS GROUP)" , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Yoshinori Sato , Rich Felker , John Paul Adrian Glaubitz , "David S. Miller" , Andreas Larsson , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , , "H. Peter Anvin" , Chris Zankel , Max Filippov CC: LKML , Srikar Dronamraju , Dietmar Eggemann , Kees Cook , mrigendrachaubey , Marc Zyngier , Pengjie Zhang , Thierry Reding , Xi Ruoyao , "Rafael J. Wysocki (Intel)" , Tiezhu Yang , Rong Bao , Hui Wang , Frederic Weisbecker , Thorsten Blum , Josh Poimboeuf , , , , , , , , , , References: <20261016095711.1364609-1-srikar@linux.ibm.com> From: Jinjie Ruan In-Reply-To: <20261016095711.1364609-1-srikar@linux.ibm.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit X-ClientProxiedBy: kwepems100002.china.huawei.com (7.221.188.206) To kwepemk200008.china.huawei.com (7.202.194.74) 在 2026/10/16 17:56, Srikar Dronamraju 写道: > Commit 21641bd9a7a7 ("lazy tlb: fix hotplug exit race with > MMU_LAZY_TLB_SHOOTDOWN") moved the handling previously performed by > idle_task_exit() into the scheduler CPU hotplug path using > sched_force_init_mm(). > > As a result, idle_task_exit() is now an empty stub and the remaining > architecture call sites have no effect. Reviewed-by: Jinjie Ruan > > Remove the calls to idle_task_exit() and the now unused stub. > > Signed-off-by: Srikar Dronamraju > --- > arch/arm/kernel/smp.c | 2 -- > arch/arm64/kernel/smp.c | 2 -- > arch/csky/kernel/smp.c | 2 -- > arch/loongarch/kernel/smp.c | 2 -- > arch/mips/cavium-octeon/smp.c | 1 - > arch/mips/kernel/smp-bmips.c | 1 - > arch/mips/kernel/smp-cps.c | 1 - > arch/mips/loongson64/smp.c | 1 - > arch/parisc/kernel/process.c | 2 -- > arch/powerpc/platforms/85xx/smp.c | 2 -- > arch/powerpc/platforms/powermac/smp.c | 2 -- > arch/powerpc/platforms/powernv/smp.c | 1 - > arch/powerpc/platforms/pseries/hotplug-cpu.c | 2 -- > arch/powerpc/platforms/pseries/pmem.c | 1 - > arch/riscv/kernel/cpu-hotplug.c | 2 -- > arch/s390/kernel/smp.c | 1 - > arch/sh/kernel/smp.c | 1 - > arch/sparc/kernel/smp_64.c | 2 -- > arch/x86/kernel/smpboot.c | 2 -- > arch/xtensa/kernel/smp.c | 1 - > include/linux/sched/hotplug.h | 2 -- > 21 files changed, 33 deletions(-) > > diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c > index b5fb4697bc3f..bbfbbe728b7a 100644 > --- a/arch/arm/kernel/smp.c > +++ b/arch/arm/kernel/smp.c > @@ -319,8 +319,6 @@ void __noreturn arch_cpu_idle_dead(void) > { > unsigned int cpu = smp_processor_id(); > > - idle_task_exit(); > - > local_irq_disable(); > > /* > diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c > index a61dc3016a11..afb5aa65d737 100644 > --- a/arch/arm64/kernel/smp.c > +++ b/arch/arm64/kernel/smp.c > @@ -370,8 +370,6 @@ void __noreturn cpu_die(void) > unsigned int cpu = smp_processor_id(); > const struct cpu_operations *ops = get_cpu_ops(cpu); > > - idle_task_exit(); > - > local_daif_mask(); > > /* Tell cpuhp_bp_sync_dead() that this CPU is now safe to dispose of */ > diff --git a/arch/csky/kernel/smp.c b/arch/csky/kernel/smp.c > index 92dbbf3e0205..e6333ccc335a 100644 > --- a/arch/csky/kernel/smp.c > +++ b/arch/csky/kernel/smp.c > @@ -294,8 +294,6 @@ void arch_cpuhp_cleanup_dead_cpu(unsigned int cpu) > > void __noreturn arch_cpu_idle_dead(void) > { > - idle_task_exit(); > - > cpuhp_ap_report_dead(); > > while (!secondary_stack) > diff --git a/arch/loongarch/kernel/smp.c b/arch/loongarch/kernel/smp.c > index 11f54837f56c..6b21af1c25e0 100644 > --- a/arch/loongarch/kernel/smp.c > +++ b/arch/loongarch/kernel/smp.c > @@ -478,7 +478,6 @@ static void __noreturn idle_play_dead(void) > register uint64_t addr; > register void (*init_fn)(void); > > - idle_task_exit(); > local_irq_enable(); > set_csr_ecfg(ECFGF_IPI); > __this_cpu_write(cpu_state, CPU_DEAD); > @@ -503,7 +502,6 @@ static void __noreturn poll_play_dead(void) > register uint64_t addr; > register void (*init_fn)(void); > > - idle_task_exit(); > __this_cpu_write(cpu_state, CPU_DEAD); > > __smp_mb(); > diff --git a/arch/mips/cavium-octeon/smp.c b/arch/mips/cavium-octeon/smp.c > index 054e331b3202..0e557e76d616 100644 > --- a/arch/mips/cavium-octeon/smp.c > +++ b/arch/mips/cavium-octeon/smp.c > @@ -344,7 +344,6 @@ void play_dead(void) > { > int cpu = cpu_number_map(cvmx_get_core_num()); > > - idle_task_exit(); > cpuhp_ap_report_dead(); > octeon_processor_boot = 0xff; > per_cpu(cpu_state, cpu) = CPU_DEAD; > diff --git a/arch/mips/kernel/smp-bmips.c b/arch/mips/kernel/smp-bmips.c > index 35b8d810833c..e4a523b7c988 100644 > --- a/arch/mips/kernel/smp-bmips.c > +++ b/arch/mips/kernel/smp-bmips.c > @@ -391,7 +391,6 @@ static void bmips_cpu_die(unsigned int cpu) > > void __ref play_dead(void) > { > - idle_task_exit(); > cpuhp_ap_report_dead(); > > /* flush data cache */ > diff --git a/arch/mips/kernel/smp-cps.c b/arch/mips/kernel/smp-cps.c > index b01ebaace48e..51e68a42bcc8 100644 > --- a/arch/mips/kernel/smp-cps.c > +++ b/arch/mips/kernel/smp-cps.c > @@ -804,7 +804,6 @@ void play_dead(void) > unsigned int cpu; > > local_irq_disable(); > - idle_task_exit(); > cpu = smp_processor_id(); > cpu_death = CPU_DEATH_POWER; > > diff --git a/arch/mips/loongson64/smp.c b/arch/mips/loongson64/smp.c > index e584299d0fde..73eca9c44b04 100644 > --- a/arch/mips/loongson64/smp.c > +++ b/arch/mips/loongson64/smp.c > @@ -766,7 +766,6 @@ void play_dead(void) > unsigned int cpu = smp_processor_id(); > void (*play_dead_at_ckseg1)(int *); > > - idle_task_exit(); > cpuhp_ap_report_dead(); > > prid_imp = read_c0_prid() & PRID_IMP_MASK; > diff --git a/arch/parisc/kernel/process.c b/arch/parisc/kernel/process.c > index 703644e5bfc4..8606ecde4c30 100644 > --- a/arch/parisc/kernel/process.c > +++ b/arch/parisc/kernel/process.c > @@ -164,8 +164,6 @@ EXPORT_SYMBOL(running_on_qemu); > void __noreturn arch_cpu_idle_dead(void) > { > #ifdef CONFIG_HOTPLUG_CPU > - idle_task_exit(); > - > local_irq_disable(); > > /* Tell the core that this CPU is now safe to dispose of. */ > diff --git a/arch/powerpc/platforms/85xx/smp.c b/arch/powerpc/platforms/85xx/smp.c > index 32fa5fb557c0..9dc81e4226f0 100644 > --- a/arch/powerpc/platforms/85xx/smp.c > +++ b/arch/powerpc/platforms/85xx/smp.c > @@ -121,8 +121,6 @@ static void smp_85xx_cpu_offline_self(void) > /* mask all irqs to prevent cpu wakeup */ > qoriq_pm_ops->irq_mask(cpu); > > - idle_task_exit(); > - > mtspr(SPRN_TCR, 0); > mtspr(SPRN_TSR, mfspr(SPRN_TSR)); > > diff --git a/arch/powerpc/platforms/powermac/smp.c b/arch/powerpc/platforms/powermac/smp.c > index 88e92af8acf9..f8e674cfcdd7 100644 > --- a/arch/powerpc/platforms/powermac/smp.c > +++ b/arch/powerpc/platforms/powermac/smp.c > @@ -925,7 +925,6 @@ static void pmac_cpu_offline_self(void) > int cpu = smp_processor_id(); > > local_irq_disable(); > - idle_task_exit(); > pr_debug("CPU%d offline\n", cpu); > generic_set_cpu_dead(cpu); > smp_wmb(); > @@ -940,7 +939,6 @@ static void pmac_cpu_offline_self(void) > int cpu = smp_processor_id(); > > local_irq_disable(); > - idle_task_exit(); > > /* > * turn off as much as possible, we'll be > diff --git a/arch/powerpc/platforms/powernv/smp.c b/arch/powerpc/platforms/powernv/smp.c > index b1201dbafcaf..9a480c924020 100644 > --- a/arch/powerpc/platforms/powernv/smp.c > +++ b/arch/powerpc/platforms/powernv/smp.c > @@ -172,7 +172,6 @@ static void pnv_cpu_offline_self(void) > > /* Standard hot unplug procedure */ > > - idle_task_exit(); > cpu = smp_processor_id(); > DBG("CPU%d offline\n", cpu); > generic_set_cpu_dead(cpu); > diff --git a/arch/powerpc/platforms/pseries/hotplug-cpu.c b/arch/powerpc/platforms/pseries/hotplug-cpu.c > index bc6926dbf148..1ade9a811157 100644 > --- a/arch/powerpc/platforms/pseries/hotplug-cpu.c > +++ b/arch/powerpc/platforms/pseries/hotplug-cpu.c > @@ -19,7 +19,6 @@ > #include > #include > #include > -#include /* for idle_task_exit */ > #include > #include > #include > @@ -64,7 +63,6 @@ static void pseries_cpu_offline_self(void) > unsigned int hwcpu = hard_smp_processor_id(); > > local_irq_disable(); > - idle_task_exit(); > if (xive_enabled()) > xive_teardown_cpu(); > else > diff --git a/arch/powerpc/platforms/pseries/pmem.c b/arch/powerpc/platforms/pseries/pmem.c > index 0f1d45f32e4a..af48dfebb640 100644 > --- a/arch/powerpc/platforms/pseries/pmem.c > +++ b/arch/powerpc/platforms/pseries/pmem.c > @@ -9,7 +9,6 @@ > #include > #include > #include > -#include /* for idle_task_exit */ > #include > #include > #include > diff --git a/arch/riscv/kernel/cpu-hotplug.c b/arch/riscv/kernel/cpu-hotplug.c > index 0bc56d8381b6..348043122593 100644 > --- a/arch/riscv/kernel/cpu-hotplug.c > +++ b/arch/riscv/kernel/cpu-hotplug.c > @@ -66,8 +66,6 @@ void arch_cpuhp_cleanup_dead_cpu(unsigned int cpu) > */ > void __noreturn arch_cpu_idle_dead(void) > { > - idle_task_exit(); > - > cpuhp_ap_report_dead(); > > cpu_ops->cpu_stop(); > diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c > index 32499cad86f0..dd1d40ec5440 100644 > --- a/arch/s390/kernel/smp.c > +++ b/arch/s390/kernel/smp.c > @@ -918,7 +918,6 @@ void __cpu_die(unsigned int cpu) > > void __noreturn cpu_die(void) > { > - idle_task_exit(); > pcpu_sigp_retry(this_cpu_ptr(&pcpu_devices), SIGP_STOP, 0); > for (;;) ; > } > diff --git a/arch/sh/kernel/smp.c b/arch/sh/kernel/smp.c > index 108d808767fa..afd57bdce04e 100644 > --- a/arch/sh/kernel/smp.c > +++ b/arch/sh/kernel/smp.c > @@ -108,7 +108,6 @@ int native_cpu_disable(unsigned int cpu) > > void play_dead_common(void) > { > - idle_task_exit(); > irq_ctx_exit(raw_smp_processor_id()); > mb(); > > diff --git a/arch/sparc/kernel/smp_64.c b/arch/sparc/kernel/smp_64.c > index 371460e34484..e98b5ddebc9e 100644 > --- a/arch/sparc/kernel/smp_64.c > +++ b/arch/sparc/kernel/smp_64.c > @@ -1290,8 +1290,6 @@ void cpu_play_dead(void) > int cpu = smp_processor_id(); > unsigned long pstate; > > - idle_task_exit(); > - > if (tlb_type == hypervisor) { > struct trap_per_cpu *tb = &trap_block[cpu]; > > diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c > index ba01a9e919b7..dcbaf3f27862 100644 > --- a/arch/x86/kernel/smpboot.c > +++ b/arch/x86/kernel/smpboot.c > @@ -1407,8 +1407,6 @@ int native_cpu_disable(void) > > void play_dead_common(void) > { > - idle_task_exit(); > - > cpuhp_ap_report_dead(); > > local_irq_disable(); > diff --git a/arch/xtensa/kernel/smp.c b/arch/xtensa/kernel/smp.c > index e4c25d0c2158..094e1da933a6 100644 > --- a/arch/xtensa/kernel/smp.c > +++ b/arch/xtensa/kernel/smp.c > @@ -336,7 +336,6 @@ void __noreturn arch_cpu_idle_dead(void) > */ > void __ref cpu_die(void) > { > - idle_task_exit(); > local_irq_disable(); > __asm__ __volatile__( > " movi a2, cpu_restart\n" > diff --git a/include/linux/sched/hotplug.h b/include/linux/sched/hotplug.h > index 17e04859b9a4..18fa3e63123e 100644 > --- a/include/linux/sched/hotplug.h > +++ b/include/linux/sched/hotplug.h > @@ -18,6 +18,4 @@ extern int sched_cpu_dying(unsigned int cpu); > # define sched_cpu_dying NULL > #endif > > -static inline void idle_task_exit(void) {} > - > #endif /* _LINUX_SCHED_HOTPLUG_H */ -- Best regards, Jinjie