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Subject: Re: [RFC PATCH v2 2/2] lib, stackdepot: Add helper to print stack
 entries.
To:     Vlastimil Babka <vbabka@suse.cz>, geert@linux-m68k.org,
        akpm@linux-foundation.org, ryabinin.a.a@gmail.com,
        glider@google.com, andreyknvl@gmail.com, dvyukov@google.com
Cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org
References: <20210902000154.1096484-1-imran.f.khan@oracle.com>
 <20210902000154.1096484-3-imran.f.khan@oracle.com>
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From:   imran.f.khan@oracle.com
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Date:   Wed, 15 Sep 2021 13:29:38 +1000
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On 14/9/21 7:01 pm, Vlastimil Babka wrote:
> On 9/2/21 02:01, Imran Khan wrote:
>> To print a stack entries, users of stackdepot, first
>> use stack_depot_fetch to get a list of stack entries
>> and then use stack_trace_print to print this list.
>> Provide a helper in stackdepot to print stack entries
>> based on stackdepot handle.
>> Also change above mentioned users to use this helper.
>>

[...]
>>   
>> +/**
>> + * stack_depot_print - print stack entries from a depot
>> + *
>> + * @handle:		Stack depot handle which was returned from
>> + *			stack_depot_save().
>> + *
>> + */
>> +void stack_depot_print(depot_stack_handle_t stack)
>> +{
>> +	unsigned long *entries;
>> +	unsigned int nr_entries;
>> +
>> +	nr_entries = stack_depot_fetch(stack, &entries);
> 
> Maybe this should also skip stack_trace_print when nr_entries is 0, to avoid
> the warning. While the callers added by this patch check handle != 0, future
> ones might not.
> 
Agree. I have incorporated this suggestion in latest version [1]

[1] 
https://lore.kernel.org/lkml/20210915014806.3206938-1-imran.f.khan@oracle.com/

Thanks
   -- Imran