Re: [patch 04/39] sound: Use hrtimer_resolution instead of hrtimer_get_res()

From: Takashi Iwai <tiwai@suse.de>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: LKML <linux-kernel@vger.kernel.org>,
	Peter Zijlstra <peterz@infradead.org>,
	Ingo Molnar <mingo@kernel.org>,
	Preeti U Murthy <preeti@linux.vnet.ibm.com>,
	Viresh Kumar <viresh.kumar@linaro.org>,
	Marcelo Tosatti <mtosatt@redhat.com>,
	Frederic Weisbecker <fweisbec@gmail.com>,
	Jaroslav Kysela <perex@perex.cz>,
	alsa-devel@alsa-project.org
Subject: Re: [patch 04/39] sound: Use hrtimer_resolution instead of hrtimer_get_res()
Date: Thu, 16 Apr 2015 10:07:15 +0200	[thread overview]
Message-ID: <s5h618wsdho.wl-tiwai@suse.de> (raw)
In-Reply-To: <20150414203500.799133359@linutronix.de>

At Tue, 14 Apr 2015 21:08:30 -0000,
Thomas Gleixner wrote:
> 
> No point in converting a timespec now that the value is directly
> accessible. Get rid of the null check while at it. Resolution is
> guaranteed to be > 0.
> 
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> Cc: Jaroslav Kysela <perex@perex.cz>
> Cc: Takashi Iwai <tiwai@suse.de>

Would you like me picking up this through sound git tree, or apply the
whole set through tip?  In the latter case, feel free to take my ack:
  Acked-by: Takashi Iwai <tiwai@suse.de>

thanks,

Takashi

> Cc: alsa-devel@alsa-project.org
> ---
>  sound/core/hrtimer.c      |    9 +--------
>  sound/drivers/pcsp/pcsp.c |   15 ++++++---------
>  2 files changed, 7 insertions(+), 17 deletions(-)
> 
> Index: tip/sound/core/hrtimer.c
> ===================================================================
> --- tip.orig/sound/core/hrtimer.c
> +++ tip/sound/core/hrtimer.c
> @@ -121,16 +121,9 @@ static struct snd_timer *mytimer;
>  static int __init snd_hrtimer_init(void)
>  {
>  	struct snd_timer *timer;
> -	struct timespec tp;
>  	int err;
>  
> -	hrtimer_get_res(CLOCK_MONOTONIC, &tp);
> -	if (tp.tv_sec > 0 || !tp.tv_nsec) {
> -		pr_err("snd-hrtimer: Invalid resolution %u.%09u",
> -			   (unsigned)tp.tv_sec, (unsigned)tp.tv_nsec);
> -		return -EINVAL;
> -	}
> -	resolution = tp.tv_nsec;
> +	resolution = hrtimer_resolution;
>  
>  	/* Create a new timer and set up the fields */
>  	err = snd_timer_global_new("hrtimer", SNDRV_TIMER_GLOBAL_HRTIMER,
> Index: tip/sound/drivers/pcsp/pcsp.c
> ===================================================================
> --- tip.orig/sound/drivers/pcsp/pcsp.c
> +++ tip/sound/drivers/pcsp/pcsp.c
> @@ -42,16 +42,13 @@ struct snd_pcsp pcsp_chip;
>  static int snd_pcsp_create(struct snd_card *card)
>  {
>  	static struct snd_device_ops ops = { };
> -	struct timespec tp;
> -	int err;
> -	int div, min_div, order;
> -
> -	hrtimer_get_res(CLOCK_MONOTONIC, &tp);
> +	unsigned int resolution = hrtimer_resolution;
> +	int err, div, min_div, order;
>  
>  	if (!nopcm) {
> -		if (tp.tv_sec || tp.tv_nsec > PCSP_MAX_PERIOD_NS) {
> +		if (resolution > PCSP_MAX_PERIOD_NS) {
>  			printk(KERN_ERR "PCSP: Timer resolution is not sufficient "
> -				"(%linS)\n", tp.tv_nsec);
> +				"(%linS)\n", resolution);
>  			printk(KERN_ERR "PCSP: Make sure you have HPET and ACPI "
>  				"enabled.\n");
>  			printk(KERN_ERR "PCSP: Turned into nopcm mode.\n");
> @@ -59,13 +56,13 @@ static int snd_pcsp_create(struct snd_ca
>  		}
>  	}
>  
> -	if (loops_per_jiffy >= PCSP_MIN_LPJ && tp.tv_nsec <= PCSP_MIN_PERIOD_NS)
> +	if (loops_per_jiffy >= PCSP_MIN_LPJ && resolution <= PCSP_MIN_PERIOD_NS)
>  		min_div = MIN_DIV;
>  	else
>  		min_div = MAX_DIV;
>  #if PCSP_DEBUG
>  	printk(KERN_DEBUG "PCSP: lpj=%li, min_div=%i, res=%li\n",
> -	       loops_per_jiffy, min_div, tp.tv_nsec);
> +	       loops_per_jiffy, min_div, resolution);
>  #endif
>  
>  	div = MAX_DIV / min_div;
> 
> 