Subject: Re: [PATCH v9 07/10] powerpc/perf: PMU functions for Core IMC and
 hotplugging
From: Anju T Sudhakar <anju@linux.vnet.ibm.com>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: mpe@ellerman.id.au, linux-kernel@vger.kernel.org,
        linuxppc-dev@lists.ozlabs.org, ego@linux.vnet.ibm.com,
        bsingharora@gmail.com, anton@samba.org, sukadev@linux.vnet.ibm.com,
        mikey@neuling.org, stewart@linux.vnet.ibm.com, dja@axtens.net,
        eranian@google.com, hemant@linux.vnet.ibm.com,
        maddy@linux.vnet.ibm.com
References: <1496665922-702-1-git-send-email-anju@linux.vnet.ibm.com>
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 <alpine.DEB.2.20.1706061135490.1885@nanos>
 <692e037d-5367-208f-ac6f-8fd43e1643ba@linux.vnet.ibm.com>
Date: Wed, 7 Jun 2017 16:04:57 +0530
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On Wednesday 07 June 2017 11:14 AM, Anju T Sudhakar wrote:
> Hi Thomas,
>
> On Tuesday 06 June 2017 03:39 PM, Thomas Gleixner wrote:
>> On Mon, 5 Jun 2017, Anju T Sudhakar wrote:
>>> +static void cleanup_all_core_imc_memory(struct imc_pmu *pmu_ptr)
>>> +{
>>> +    struct imc_mem_info *ptr = pmu_ptr->mem_info;
>>> +
>>> +    if (!ptr)
>>> +        return;
>> That's pointless.
>
> No, it is not.  We may end up here from imc_mem_init() when the memory 
> allocation for
> pmu_ptr->mem_info fails. So in that case we can just return from here, 
> and kfree wont be
> called with a NULL pointer.
>
>>> +    for (; ptr; ptr++) {
>>        for (ptr = pmu_ptr->mem_info; ptr; ptr++) {
>>
>> will do the right thing.

Sorry, replied too soon on this. You are right, with this we can remove 
the if (!ptr) check.
thanks.
>>
>>> +        if (ptr->vbase[0] != 0)
>>> +            free_pages(ptr->vbase[0], 0);
>>> +    }
>> and kfree can be called with a NULL pointer.
>>

Yes right.

Regards,
Anju