linux-kernel - Re: [patch V4 part 1 04/36] sched: Make scheduler

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <3e191b63-9125-25a8-4784-e7a737d71b05@oracle.com>
Date:   Wed, 6 May 2020 14:42:33 +0200
From:   Alexandre Chartre <alexandre.chartre@...cle.com>
To:     Thomas Gleixner <tglx@...utronix.de>,
        LKML <linux-kernel@...r.kernel.org>
Cc:     x86@...nel.org, "Paul E. McKenney" <paulmck@...nel.org>,
        Andy Lutomirski <luto@...nel.org>,
        Frederic Weisbecker <frederic@...nel.org>,
        Paolo Bonzini <pbonzini@...hat.com>,
        Sean Christopherson <sean.j.christopherson@...el.com>,
        Masami Hiramatsu <mhiramat@...nel.org>,
        Petr Mladek <pmladek@...e.com>,
        Steven Rostedt <rostedt@...dmis.org>,
        Joel Fernandes <joel@...lfernandes.org>,
        Boris Ostrovsky <boris.ostrovsky@...cle.com>,
        Juergen Gross <jgross@...e.com>,
        Brian Gerst <brgerst@...il.com>,
        Mathieu Desnoyers <mathieu.desnoyers@...icios.com>,
        Josh Poimboeuf <jpoimboe@...hat.com>,
        Will Deacon <will@...nel.org>
Subject: Re: [patch V4 part 1 04/36] sched: Make scheduler_ipi inline


On 5/5/20 3:16 PM, Thomas Gleixner wrote:
> Now that the scheduler IPI is trivial and simple again there is no point to
> have the little function out of line. This simplifies the effort of
> constraining the instrumentation nicely.
> 
> Signed-off-by: Thomas Gleixner <tglx@...utronix.de>
> ---
>   include/linux/sched.h |   10 +++++++++-
>   kernel/sched/core.c   |   10 ----------
>   2 files changed, 9 insertions(+), 11 deletions(-)

Reviewed-by: Alexandre Chartre <alexandre.chartre@...cle.com>

alex.

> --- a/include/linux/sched.h
> +++ b/include/linux/sched.h
> @@ -1719,7 +1719,15 @@ extern char *__get_task_comm(char *to, s
>   })
>   
>   #ifdef CONFIG_SMP
> -void scheduler_ipi(void);
> +static __always_inline void scheduler_ipi(void)
> +{
> +	/*
> +	 * Fold TIF_NEED_RESCHED into the preempt_count; anybody setting
> +	 * TIF_NEED_RESCHED remotely (for the first time) will also send
> +	 * this IPI.
> +	 */
> +	preempt_fold_need_resched();
> +}
>   extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
>   #else
>   static inline void scheduler_ipi(void) { }
> --- a/kernel/sched/core.c
> +++ b/kernel/sched/core.c
> @@ -2312,16 +2312,6 @@ static void wake_csd_func(void *info)
>   	sched_ttwu_pending();
>   }
>   
> -void scheduler_ipi(void)
> -{
> -	/*
> -	 * Fold TIF_NEED_RESCHED into the preempt_count; anybody setting
> -	 * TIF_NEED_RESCHED remotely (for the first time) will also send
> -	 * this IPI.
> -	 */
> -	preempt_fold_need_resched();
> -}
> -
>   static void ttwu_queue_remote(struct task_struct *p, int cpu, int wake_flags)
>   {
>   	struct rq *rq = cpu_rq(cpu);
>