linux-kernel - Re: [PATCH v3 03/17] timer: Move store of next event into __next_timer

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]

Date:   Wed, 26 Oct 2022 11:33:04 +0200
From:   Frederic Weisbecker <frederic@...nel.org>
To:     Anna-Maria Behnsen <anna-maria@...utronix.de>
Cc:     linux-kernel@...r.kernel.org,
        Peter Zijlstra <peterz@...radead.org>,
        John Stultz <john.stultz@...aro.org>,
        Eric Dumazet <edumazet@...gle.com>,
        Thomas Gleixner <tglx@...utronix.de>,
        "Rafael J. Wysocki" <rafael.j.wysocki@...el.com>,
        linux-pm@...r.kernel.org, Arjan van de Ven <arjan@...radead.org>,
        "Paul E. McKenney" <paulmck@...ux.vnet.ibm.com>,
        Frederic Weisbecker <fweisbec@...il.com>,
        Rik van Riel <riel@...hat.com>
Subject: Re: [PATCH v3 03/17] timer: Move store of next event into
 __next_timer_interrupt()

On Tue, Oct 25, 2022 at 03:58:36PM +0200, Anna-Maria Behnsen wrote:
> Both call sides of __next_timer_interrupt() store the return value directly
> in base->next_expiry. Move the store into __next_timer_interrupt().
> 
> No functional change.
> 
> Signed-off-by: Anna-Maria Behnsen <anna-maria@...utronix.de>
> Reviewed-by: Thomas Gleixner <tglx@...utronix.de>
> ---
>  kernel/time/timer.c | 11 +++++++----
>  1 file changed, 7 insertions(+), 4 deletions(-)
> 
> diff --git a/kernel/time/timer.c b/kernel/time/timer.c
> index 717fcb9fb14a..7695c733dfa5 100644
> --- a/kernel/time/timer.c
> +++ b/kernel/time/timer.c
> @@ -1571,8 +1571,10 @@ static int next_pending_bucket(struct timer_base *base, unsigned offset,
>  /*
>   * Search the first expiring timer in the various clock levels. Caller must
>   * hold base->lock.
> + *
> + * Store next expiry time in base->next_expiry.
>   */
> -static unsigned long __next_timer_interrupt(struct timer_base *base)
> +static void __next_timer_interrupt(struct timer_base *base)
>  {
>  	unsigned long clk, next, adj;
>  	unsigned lvl, offset = 0;
> @@ -1638,10 +1640,11 @@ static unsigned long __next_timer_interrupt(struct timer_base *base)
>  		clk += adj;
>  	}
>  
> +	base->next_expiry = next;
>  	base->next_expiry_recalc = false;

In that case, maybe rename that function as next_expiry_recalc() to make its
purpose clearer?

Thanks!

>  	base->timers_pending = !(next == base->clk + NEXT_TIMER_MAX_DELTA);
>  
> -	return next;
> +	return;
>  }
>  
>  #ifdef CONFIG_NO_HZ_COMMON
> @@ -1701,7 +1704,7 @@ u64 get_next_timer_interrupt(unsigned long basej, u64 basem)
>  
>  	raw_spin_lock(&base->lock);
>  	if (base->next_expiry_recalc)
> -		base->next_expiry = __next_timer_interrupt(base);
> +		__next_timer_interrupt(base);
>  	nextevt = base->next_expiry;
>  
>  	/*
> @@ -1784,7 +1787,7 @@ static inline void __run_timers(struct timer_base *base)
>  		WARN_ON_ONCE(!levels && !base->next_expiry_recalc
>  			     && base->timers_pending);
>  		base->clk++;
> -		base->next_expiry = __next_timer_interrupt(base);
> +		__next_timer_interrupt(base);
>  
>  		while (levels--)
>  			expire_timers(base, heads + levels);
> -- 
> 2.30.2
>