Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752249AbbHCJQE (ORCPT ); Mon, 3 Aug 2015 05:16:04 -0400 Received: from mail-pa0-f45.google.com ([209.85.220.45]:33970 "EHLO mail-pa0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751522AbbHCJQC convert rfc822-to-8bit (ORCPT ); Mon, 3 Aug 2015 05:16:02 -0400 Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2098\)) Subject: Re: [PATCH] workqueue: Add the allocation flags to function schedule_on_each_cpu_gfp From: yalin wang In-Reply-To: <1438590425-30307-1-git-send-email-mnfhuang@gmail.com> Date: Mon, 3 Aug 2015 17:15:53 +0800 Cc: tj@kernel.org, rostedt@goodmis.org, mingo@redhat.com, linux-kernel@vger.kernel.org, mhuang@redhat.com Content-Transfer-Encoding: 8BIT Message-Id: <4F413CE0-A857-4350-AE04-176AA8ADC44E@gmail.com> References: <1438590425-30307-1-git-send-email-mnfhuang@gmail.com> To: Minfei Huang X-Mailer: Apple Mail (2.2098) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5768 Lines: 155 > On Aug 3, 2015, at 16:27, Minfei Huang wrote: > > Rename the function schedule_on_each_cpu to schedule_on_each_cpu_gfp to > add the allocation flags as parameter. > > In several situation in ftrace, we are nervous and never come back, once > schedule_on_each_cpu fails to alloc the percpu work. Add the allocation > flags __GFP_NOFAIL to guarantee it. > > Signed-off-by: Minfei Huang > --- > arch/x86/platform/uv/uv_time.c | 2 +- > include/linux/ftrace.h | 2 +- > include/linux/workqueue.h | 2 +- > kernel/trace/ftrace.c | 5 +++-- > kernel/trace/trace_events.c | 2 +- > kernel/workqueue.c | 11 ++++++----- > 6 files changed, 13 insertions(+), 11 deletions(-) > > diff --git a/arch/x86/platform/uv/uv_time.c b/arch/x86/platform/uv/uv_time.c > index a244237..a87a16a 100644 > --- a/arch/x86/platform/uv/uv_time.c > +++ b/arch/x86/platform/uv/uv_time.c > @@ -405,7 +405,7 @@ static __init int uv_rtc_setup_clock(void) > clock_event_device_uv.max_delta_ns = clocksource_uv.mask * > (NSEC_PER_SEC / sn_rtc_cycles_per_second); > > - rc = schedule_on_each_cpu(uv_rtc_register_clockevents); > + rc = schedule_on_each_cpu_gfp(uv_rtc_register_clockevents, GFP_KERNEL); > if (rc) { > x86_platform_ipi_callback = NULL; > uv_rtc_deallocate_timers(); > diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h > index 6cd8c0e..d6d3cf5 100644 > --- a/include/linux/ftrace.h > +++ b/include/linux/ftrace.h > @@ -154,7 +154,7 @@ struct ftrace_ops_hash { > * > * Any private data added must also take care not to be freed and if private > * data is added to a ftrace_ops that is in core code, the user of the > - * ftrace_ops must perform a schedule_on_each_cpu() before freeing it. > + * ftrace_ops must perform a schedule_on_each_cpu_gfp() before freeing it. > */ > struct ftrace_ops { > ftrace_func_t func; > diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h > index 738b30b..2de50fe 100644 > --- a/include/linux/workqueue.h > +++ b/include/linux/workqueue.h > @@ -436,7 +436,7 @@ extern bool mod_delayed_work_on(int cpu, struct workqueue_struct *wq, > extern void flush_workqueue(struct workqueue_struct *wq); > extern void drain_workqueue(struct workqueue_struct *wq); > > -extern int schedule_on_each_cpu(work_func_t func); > +extern int schedule_on_each_cpu_gfp(work_func_t func, gfp_t gfp); > > int execute_in_process_context(work_func_t fn, struct execute_work *); > > diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c > index eb11011..f8d3111 100644 > --- a/kernel/trace/ftrace.c > +++ b/kernel/trace/ftrace.c > @@ -324,7 +324,7 @@ static void update_ftrace_function(void) > * Make sure all CPUs see this. Yes this is slow, but static > * tracing is slow and nasty to have enabled. > */ > - schedule_on_each_cpu(ftrace_sync); > + schedule_on_each_cpu_gfp(ftrace_sync, GFP_KERNEL | __GFP_NOFAIL); > /* Now all cpus are using the list ops. */ > function_trace_op = set_function_trace_op; > /* Make sure the function_trace_op is visible on all CPUs */ > @@ -2716,7 +2716,8 @@ static int ftrace_shutdown(struct ftrace_ops *ops, int command) > * ourselves. > */ > if (ops->flags & (FTRACE_OPS_FL_DYNAMIC | FTRACE_OPS_FL_CONTROL)) { > - schedule_on_each_cpu(ftrace_sync); > + schedule_on_each_cpu_gfp(ftrace_sync, > + GFP_KERNEL | __GFP_NOFAIL); > > arch_ftrace_trampoline_free(ops); > > diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c > index 404a372..6cf0dba 100644 > --- a/kernel/trace/trace_events.c > +++ b/kernel/trace/trace_events.c > @@ -2722,7 +2722,7 @@ static __init int event_test_thread(void *unused) > if (!test_malloc) > pr_info("failed to kmalloc\n"); > > - schedule_on_each_cpu(test_work); > + schedule_on_each_cpu_gfp(test_work, GFP_KERNEL); > > kfree(test_malloc); > > diff --git a/kernel/workqueue.c b/kernel/workqueue.c > index 4c4f061..f7ef6bb 100644 > --- a/kernel/workqueue.c > +++ b/kernel/workqueue.c > @@ -2917,22 +2917,23 @@ bool cancel_delayed_work_sync(struct delayed_work *dwork) > EXPORT_SYMBOL(cancel_delayed_work_sync); > > /** > - * schedule_on_each_cpu - execute a function synchronously on each online CPU > + * schedule_on_each_cpu_gfp - execute function synchronously on each online CPU > * @func: the function to call > + * @gfp: allocation flags > * > - * schedule_on_each_cpu() executes @func on each online CPU using the > + * schedule_on_each_cpu_gfp() executes @func on each online CPU using the > * system workqueue and blocks until all CPUs have completed. > - * schedule_on_each_cpu() is very slow. > + * schedule_on_each_cpu_gfp() is very slow. > * > * Return: > * 0 on success, -errno on failure. > */ > -int schedule_on_each_cpu(work_func_t func) > +int schedule_on_each_cpu_gfp(work_func_t func, gfp_t gfp) > { > int cpu; > struct work_struct __percpu *works; > > - works = alloc_percpu(struct work_struct); > + works = alloc_percpu_gfp(struct work_struct, gfp); > if (!works) > return -ENOMEM; > > -- > 2.4.0 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ better to also provide a wrapper function with name schedule_on_each_cpu(), as this function is used frequently . #define schedule_on_each_cpu(f) schedule_on_each_cpu_gfp(f, GFP_KERNEL) Thanks -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/