Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Subject: Re: [PATCH v1 2/3] driver core: Read atomic counter once in
 driver_probe_done()
To:     Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "Rafael J. Wysocki" <rafael@kernel.org>,
        linux-kernel@vger.kernel.org
References: <20200309141111.40576-1-andriy.shevchenko@linux.intel.com>
 <20200309141111.40576-2-andriy.shevchenko@linux.intel.com>
From:   Ferry Toth <fntoth@gmail.com>
Message-ID: <80e2fbb3-c69d-c2a8-f177-25c304062b29@gmail.com>
Date:   Thu, 19 Mar 2020 00:49:09 +0100
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101
 Thunderbird/68.4.1
MIME-Version: 1.0
In-Reply-To: <20200309141111.40576-2-andriy.shevchenko@linux.intel.com>
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Op 09-03-2020 om 15:11 schreef Andy Shevchenko:
> Between printing the debug message and actual check atomic counter can be
> altered. For better debugging experience read atomic counter value only once.
> 
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

Tested-by: Ferry Toth <fntoth@gmail.com>

> ---
>   drivers/base/dd.c | 7 ++++---
>   1 file changed, 4 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/base/dd.c b/drivers/base/dd.c
> index 43720beb5300..efd0e4c16ba5 100644
> --- a/drivers/base/dd.c
> +++ b/drivers/base/dd.c
> @@ -669,9 +669,10 @@ static int really_probe_debug(struct device *dev, struct device_driver *drv)
>    */
>   int driver_probe_done(void)
>   {
> -	pr_debug("%s: probe_count = %d\n", __func__,
> -		 atomic_read(&probe_count));
> -	if (atomic_read(&probe_count))
> +	int local_probe_count = atomic_read(&probe_count);
> +
> +	pr_debug("%s: probe_count = %d\n", __func__, local_probe_count);
> +	if (local_probe_count)
>   		return -EBUSY;
>   	return 0;
>   }
>