From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joel Fernandes Subject: Re: [PATCH v2 1/9] rcu: Rename rcu_irq_{enter,exit}_irqson() Date: Wed, 12 Feb 2020 17:38:37 -0500 Message-ID: <20200212223837.GB115917@google.com> References: <20200212210139.382424693@infradead.org> <20200212210749.858223764@infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20200212210749.858223764@infradead.org> Sender: linux-kernel-owner@vger.kernel.org To: Peter Zijlstra Cc: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, rostedt@goodmis.org, mingo@kernel.org, gregkh@linuxfoundation.org, gustavo@embeddedor.com, tglx@linutronix.de, paulmck@kernel.org, josh@joshtriplett.org, mathieu.desnoyers@efficios.com, jiangshanlai@gmail.com List-Id: linux-arch.vger.kernel.org On Wed, Feb 12, 2020 at 10:01:40PM +0100, Peter Zijlstra wrote: > The functions do in fact use local_irq_{save,restore}() and can > therefore be used when IRQs are in fact disabled. Worse, they are > already used in places where IRQs are disabled, leading to great > confusion when reading the code. > > Rename them to fix this confusion. Reviewed-by: Joel Fernandes (Google) thanks, - Joel > > Signed-off-by: Peter Zijlstra (Intel) > --- > include/linux/rcupdate.h | 4 ++-- > include/linux/rcutiny.h | 4 ++-- > include/linux/rcutree.h | 4 ++-- > include/linux/tracepoint.h | 4 ++-- > kernel/cpu_pm.c | 4 ++-- > kernel/rcu/tree.c | 8 ++++---- > kernel/trace/trace.c | 4 ++-- > 7 files changed, 16 insertions(+), 16 deletions(-) > > --- a/include/linux/rcupdate.h > +++ b/include/linux/rcupdate.h > @@ -120,9 +120,9 @@ static inline void rcu_init_nohz(void) { > */ > #define RCU_NONIDLE(a) \ > do { \ > - rcu_irq_enter_irqson(); \ > + rcu_irq_enter_irqsave(); \ > do { a; } while (0); \ > - rcu_irq_exit_irqson(); \ > + rcu_irq_exit_irqsave(); \ > } while (0) > > /* > --- a/include/linux/rcutiny.h > +++ b/include/linux/rcutiny.h > @@ -68,8 +68,8 @@ static inline int rcu_jiffies_till_stall > static inline void rcu_idle_enter(void) { } > static inline void rcu_idle_exit(void) { } > static inline void rcu_irq_enter(void) { } > -static inline void rcu_irq_exit_irqson(void) { } > -static inline void rcu_irq_enter_irqson(void) { } > +static inline void rcu_irq_exit_irqsave(void) { } > +static inline void rcu_irq_enter_irqsave(void) { } > static inline void rcu_irq_exit(void) { } > static inline void exit_rcu(void) { } > static inline bool rcu_preempt_need_deferred_qs(struct task_struct *t) > --- a/include/linux/rcutree.h > +++ b/include/linux/rcutree.h > @@ -46,8 +46,8 @@ void rcu_idle_enter(void); > void rcu_idle_exit(void); > void rcu_irq_enter(void); > void rcu_irq_exit(void); > -void rcu_irq_enter_irqson(void); > -void rcu_irq_exit_irqson(void); > +void rcu_irq_enter_irqsave(void); > +void rcu_irq_exit_irqsave(void); > > void exit_rcu(void); > > --- a/include/linux/tracepoint.h > +++ b/include/linux/tracepoint.h > @@ -181,7 +181,7 @@ static inline struct tracepoint *tracepo > */ \ > if (rcuidle) { \ > __idx = srcu_read_lock_notrace(&tracepoint_srcu);\ > - rcu_irq_enter_irqson(); \ > + rcu_irq_enter_irqsave(); \ > } \ > \ > it_func_ptr = rcu_dereference_raw((tp)->funcs); \ > @@ -195,7 +195,7 @@ static inline struct tracepoint *tracepo > } \ > \ > if (rcuidle) { \ > - rcu_irq_exit_irqson(); \ > + rcu_irq_exit_irqsave(); \ > srcu_read_unlock_notrace(&tracepoint_srcu, __idx);\ > } \ > \ > --- a/kernel/cpu_pm.c > +++ b/kernel/cpu_pm.c > @@ -24,10 +24,10 @@ static int cpu_pm_notify(enum cpu_pm_eve > * could be disfunctional in cpu idle. Copy RCU_NONIDLE code to let > * RCU know this. > */ > - rcu_irq_enter_irqson(); > + rcu_irq_enter_irqsave(); > ret = __atomic_notifier_call_chain(&cpu_pm_notifier_chain, event, NULL, > nr_to_call, nr_calls); > - rcu_irq_exit_irqson(); > + rcu_irq_exit_irqsave(); > > return notifier_to_errno(ret); > } > --- a/kernel/rcu/tree.c > +++ b/kernel/rcu/tree.c > @@ -699,10 +699,10 @@ void rcu_irq_exit(void) > /* > * Wrapper for rcu_irq_exit() where interrupts are enabled. > * > - * If you add or remove a call to rcu_irq_exit_irqson(), be sure to test > + * If you add or remove a call to rcu_irq_exit_irqsave(), be sure to test > * with CONFIG_RCU_EQS_DEBUG=y. > */ > -void rcu_irq_exit_irqson(void) > +void rcu_irq_exit_irqsave(void) > { > unsigned long flags; > > @@ -875,10 +875,10 @@ void rcu_irq_enter(void) > /* > * Wrapper for rcu_irq_enter() where interrupts are enabled. > * > - * If you add or remove a call to rcu_irq_enter_irqson(), be sure to test > + * If you add or remove a call to rcu_irq_enter_irqsave(), be sure to test > * with CONFIG_RCU_EQS_DEBUG=y. > */ > -void rcu_irq_enter_irqson(void) > +void rcu_irq_enter_irqsave(void) > { > unsigned long flags; > > --- a/kernel/trace/trace.c > +++ b/kernel/trace/trace.c > @@ -3004,9 +3004,9 @@ void __trace_stack(struct trace_array *t > if (unlikely(in_nmi())) > return; > > - rcu_irq_enter_irqson(); > + rcu_irq_enter_irqsave(); > __ftrace_trace_stack(buffer, flags, skip, pc, NULL); > - rcu_irq_exit_irqson(); > + rcu_irq_exit_irqsave(); > } > > /** > > From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qk1-f193.google.com ([209.85.222.193]:42547 "EHLO mail-qk1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727692AbgBLWip (ORCPT ); Wed, 12 Feb 2020 17:38:45 -0500 Received: by mail-qk1-f193.google.com with SMTP id o28so2432124qkj.9 for ; Wed, 12 Feb 2020 14:38:44 -0800 (PST) Date: Wed, 12 Feb 2020 17:38:37 -0500 From: Joel Fernandes Subject: Re: [PATCH v2 1/9] rcu: Rename rcu_irq_{enter,exit}_irqson() Message-ID: <20200212223837.GB115917@google.com> References: <20200212210139.382424693@infradead.org> <20200212210749.858223764@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200212210749.858223764@infradead.org> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Peter Zijlstra Cc: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, rostedt@goodmis.org, mingo@kernel.org, gregkh@linuxfoundation.org, gustavo@embeddedor.com, tglx@linutronix.de, paulmck@kernel.org, josh@joshtriplett.org, mathieu.desnoyers@efficios.com, jiangshanlai@gmail.com Message-ID: <20200212223837.Qo3RH3ia_NECSR5aVwNIUrdlIeAsEaUQqzCrkYSplu4@z> On Wed, Feb 12, 2020 at 10:01:40PM +0100, Peter Zijlstra wrote: > The functions do in fact use local_irq_{save,restore}() and can > therefore be used when IRQs are in fact disabled. Worse, they are > already used in places where IRQs are disabled, leading to great > confusion when reading the code. > > Rename them to fix this confusion. Reviewed-by: Joel Fernandes (Google) thanks, - Joel > > Signed-off-by: Peter Zijlstra (Intel) > --- > include/linux/rcupdate.h | 4 ++-- > include/linux/rcutiny.h | 4 ++-- > include/linux/rcutree.h | 4 ++-- > include/linux/tracepoint.h | 4 ++-- > kernel/cpu_pm.c | 4 ++-- > kernel/rcu/tree.c | 8 ++++---- > kernel/trace/trace.c | 4 ++-- > 7 files changed, 16 insertions(+), 16 deletions(-) > > --- a/include/linux/rcupdate.h > +++ b/include/linux/rcupdate.h > @@ -120,9 +120,9 @@ static inline void rcu_init_nohz(void) { > */ > #define RCU_NONIDLE(a) \ > do { \ > - rcu_irq_enter_irqson(); \ > + rcu_irq_enter_irqsave(); \ > do { a; } while (0); \ > - rcu_irq_exit_irqson(); \ > + rcu_irq_exit_irqsave(); \ > } while (0) > > /* > --- a/include/linux/rcutiny.h > +++ b/include/linux/rcutiny.h > @@ -68,8 +68,8 @@ static inline int rcu_jiffies_till_stall > static inline void rcu_idle_enter(void) { } > static inline void rcu_idle_exit(void) { } > static inline void rcu_irq_enter(void) { } > -static inline void rcu_irq_exit_irqson(void) { } > -static inline void rcu_irq_enter_irqson(void) { } > +static inline void rcu_irq_exit_irqsave(void) { } > +static inline void rcu_irq_enter_irqsave(void) { } > static inline void rcu_irq_exit(void) { } > static inline void exit_rcu(void) { } > static inline bool rcu_preempt_need_deferred_qs(struct task_struct *t) > --- a/include/linux/rcutree.h > +++ b/include/linux/rcutree.h > @@ -46,8 +46,8 @@ void rcu_idle_enter(void); > void rcu_idle_exit(void); > void rcu_irq_enter(void); > void rcu_irq_exit(void); > -void rcu_irq_enter_irqson(void); > -void rcu_irq_exit_irqson(void); > +void rcu_irq_enter_irqsave(void); > +void rcu_irq_exit_irqsave(void); > > void exit_rcu(void); > > --- a/include/linux/tracepoint.h > +++ b/include/linux/tracepoint.h > @@ -181,7 +181,7 @@ static inline struct tracepoint *tracepo > */ \ > if (rcuidle) { \ > __idx = srcu_read_lock_notrace(&tracepoint_srcu);\ > - rcu_irq_enter_irqson(); \ > + rcu_irq_enter_irqsave(); \ > } \ > \ > it_func_ptr = rcu_dereference_raw((tp)->funcs); \ > @@ -195,7 +195,7 @@ static inline struct tracepoint *tracepo > } \ > \ > if (rcuidle) { \ > - rcu_irq_exit_irqson(); \ > + rcu_irq_exit_irqsave(); \ > srcu_read_unlock_notrace(&tracepoint_srcu, __idx);\ > } \ > \ > --- a/kernel/cpu_pm.c > +++ b/kernel/cpu_pm.c > @@ -24,10 +24,10 @@ static int cpu_pm_notify(enum cpu_pm_eve > * could be disfunctional in cpu idle. Copy RCU_NONIDLE code to let > * RCU know this. > */ > - rcu_irq_enter_irqson(); > + rcu_irq_enter_irqsave(); > ret = __atomic_notifier_call_chain(&cpu_pm_notifier_chain, event, NULL, > nr_to_call, nr_calls); > - rcu_irq_exit_irqson(); > + rcu_irq_exit_irqsave(); > > return notifier_to_errno(ret); > } > --- a/kernel/rcu/tree.c > +++ b/kernel/rcu/tree.c > @@ -699,10 +699,10 @@ void rcu_irq_exit(void) > /* > * Wrapper for rcu_irq_exit() where interrupts are enabled. > * > - * If you add or remove a call to rcu_irq_exit_irqson(), be sure to test > + * If you add or remove a call to rcu_irq_exit_irqsave(), be sure to test > * with CONFIG_RCU_EQS_DEBUG=y. > */ > -void rcu_irq_exit_irqson(void) > +void rcu_irq_exit_irqsave(void) > { > unsigned long flags; > > @@ -875,10 +875,10 @@ void rcu_irq_enter(void) > /* > * Wrapper for rcu_irq_enter() where interrupts are enabled. > * > - * If you add or remove a call to rcu_irq_enter_irqson(), be sure to test > + * If you add or remove a call to rcu_irq_enter_irqsave(), be sure to test > * with CONFIG_RCU_EQS_DEBUG=y. > */ > -void rcu_irq_enter_irqson(void) > +void rcu_irq_enter_irqsave(void) > { > unsigned long flags; > > --- a/kernel/trace/trace.c > +++ b/kernel/trace/trace.c > @@ -3004,9 +3004,9 @@ void __trace_stack(struct trace_array *t > if (unlikely(in_nmi())) > return; > > - rcu_irq_enter_irqson(); > + rcu_irq_enter_irqsave(); > __ftrace_trace_stack(buffer, flags, skip, pc, NULL); > - rcu_irq_exit_irqson(); > + rcu_irq_exit_irqsave(); > } > > /** > >