From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Gleixner Subject: [patch 08/18] ia64: Use generic idle thread allocation Date: Fri, 20 Apr 2012 13:05:49 -0000 Message-ID: <20120420124557.380965133@linutronix.de> References: <20120420122120.097464672@linutronix.de> Return-path: Received: from www.linutronix.de ([62.245.132.108]:44752 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750709Ab2DTNFy (ORCPT ); Fri, 20 Apr 2012 09:05:54 -0400 Content-Disposition: inline; filename=ia64-use-generic-idle-thread-allocation.patch Sender: linux-arch-owner@vger.kernel.org List-ID: To: LKML Cc: linux-arch@vger.kernel.org, Peter Zijlstra , Rusty Russell , "Paul E. McKenney" , Ingo Molnar , "Srivatsa S. Bhat" , Tony Luck Signed-off-by: Thomas Gleixner Cc: Tony Luck --- arch/ia64/Kconfig | 1 arch/ia64/kernel/smpboot.c | 61 ++------------------------------------------- 2 files changed, 4 insertions(+), 58 deletions(-) Index: linux-2.6/arch/ia64/Kconfig =================================================================== --- linux-2.6.orig/arch/ia64/Kconfig +++ linux-2.6/arch/ia64/Kconfig @@ -33,6 +33,7 @@ config IA64 select ARCH_WANT_OPTIONAL_GPIOLIB select ARCH_HAVE_NMI_SAFE_CMPXCHG select GENERIC_IOMAP + select GENERIC_SMP_IDLE_THREAD default y help The Itanium Processor Family is Intel's 64-bit successor to Index: linux-2.6/arch/ia64/kernel/smpboot.c =================================================================== --- linux-2.6.orig/arch/ia64/kernel/smpboot.c +++ linux-2.6/arch/ia64/kernel/smpboot.c @@ -75,13 +75,6 @@ #endif /* - * Store all idle threads, this can be reused instead of creating - * a new thread. Also avoids complicated thread destroy functionality - * for idle threads. - */ -struct task_struct *idle_thread_array[NR_CPUS]; - -/* * Global array allocated for NR_CPUS at boot time */ struct sal_to_os_boot sal_boot_rendez_state[NR_CPUS]; @@ -94,13 +87,7 @@ struct sal_to_os_boot *sal_state_for_boo #define set_brendez_area(x) (sal_state_for_booting_cpu = &sal_boot_rendez_state[(x)]); -#define get_idle_for_cpu(x) (idle_thread_array[(x)]) -#define set_idle_for_cpu(x,p) (idle_thread_array[(x)] = (p)) - #else - -#define get_idle_for_cpu(x) (NULL) -#define set_idle_for_cpu(x,p) #define set_brendez_area(x) #endif @@ -480,54 +467,12 @@ struct pt_regs * __cpuinit idle_regs(str return NULL; } -struct create_idle { - struct work_struct work; - struct task_struct *idle; - struct completion done; - int cpu; -}; - -void __cpuinit -do_fork_idle(struct work_struct *work) -{ - struct create_idle *c_idle = - container_of(work, struct create_idle, work); - - c_idle->idle = fork_idle(c_idle->cpu); - complete(&c_idle->done); -} - static int __cpuinit -do_boot_cpu (int sapicid, int cpu) +do_boot_cpu (int sapicid, int cpu, struct task_struct *idle) { int timeout; - struct create_idle c_idle = { - .work = __WORK_INITIALIZER(c_idle.work, do_fork_idle), - .cpu = cpu, - .done = COMPLETION_INITIALIZER(c_idle.done), - }; - - /* - * We can't use kernel_thread since we must avoid to - * reschedule the child. - */ - c_idle.idle = get_idle_for_cpu(cpu); - if (c_idle.idle) { - init_idle(c_idle.idle, cpu); - goto do_rest; - } - - schedule_work(&c_idle.work); - wait_for_completion(&c_idle.done); - - if (IS_ERR(c_idle.idle)) - panic("failed fork for CPU %d", cpu); - - set_idle_for_cpu(cpu, c_idle.idle); - -do_rest: - task_for_booting_cpu = c_idle.idle; + task_for_booting_cpu = idle; Dprintk("Sending wakeup vector %lu to AP 0x%x/0x%x.\n", ap_wakeup_vector, cpu, sapicid); set_brendez_area(cpu); @@ -811,7 +756,7 @@ __cpu_up(unsigned int cpu, struct task_s per_cpu(cpu_state, cpu) = CPU_UP_PREPARE; /* Processor goes to start_secondary(), sets online flag */ - ret = do_boot_cpu(sapicid, cpu); + ret = do_boot_cpu(sapicid, cpu, tidle); if (ret < 0) return ret;