Re: [PM-WIP_CPUFREQ][PATCH V3 6/8] OMAP2+: cpufreq: fix freq_table leak

[Todd Poynor <toddpoynor@google.com>]

On Wed, May 25, 2011 at 04:38:51PM -0700, Nishanth Menon wrote:
> Since we have multiple CPUs, the cpuinit call for CPU1 causes
> freq_table of CPU0 to be overwritten. Instead, we maintain
> a counter to keep track of cpus who use the cpufreq table
> allocate it once(one freq table for all CPUs) and free them
> once the last user is done with it. We also need to protect
> freq_table and this new counter from updates from multiple
> contexts to be on a safe side.
> 
> Signed-off-by: Nishanth Menon <nm@ti.com>
> ---
...
>  static int freq_table_alloc(void)
>  {
> -	if (use_opp)
> -		return opp_init_cpufreq_table(mpu_dev, &freq_table);
> +	int ret = 0;
>  
> -	clk_init_cpufreq_table(&freq_table);
> -	if (!freq_table)
> -		return -ENOMEM;
> +	mutex_lock(&freq_table_lock);
>  
> -	return 0;
> +	freq_table_users++;
> +	/* Did we allocate previously? */
> +	if (freq_table_users - 1)
> +		goto out;
> +
> +	/* no, so we allocate */
> +	if (use_opp) {
> +		ret = opp_init_cpufreq_table(mpu_dev, &freq_table);
> +	} else {
> +		clk_init_cpufreq_table(&freq_table);
> +		if (!freq_table)
> +			ret = -ENOMEM;
> +	}
> +	/* if we did not allocate cleanly.. reduce user count */
> +	if (!ret)
> +		freq_table_users--;

"if (ret)" intended?  ret == 0 means allocated OK.


Todd