Re: [dm-devel] [PATCH 8/9] scsi: sd_zbc: Cleanup sd_zbc_alloc_report_buffer()

[Damien Le Moal <Damien.LeMoal@wdc.com>]

On 2019/11/09 4:06, Bart Van Assche wrote:
> On 11/7/19 5:57 PM, Damien Le Moal wrote:
>> -	buf = vzalloc(bufsize);
>> -	if (buf)
>> -		*buflen = bufsize;
>> +	while (bufsize >= SECTOR_SIZE) {
>> +		buf = vzalloc(bufsize);
>> +		if (buf) {
>> +			*buflen = bufsize;
>> +			return buf;
>> +		}
>> +		bufsize >>= 1;
>> +	}
> 
> Hi Damien,
> 
> Has it been considered to pass the __GFP_NORETRY flag to this vzalloc() 
> call?

Do you mean using

__vmalloc(bufsize,
	  GFP_KERNEL | __GFP_ZERO | __GFP_NORETRY, PAGE_KERNEL);

instead of vzalloc() ? (since we cannot pass GFP flags to vzalloc()...)

Note that this is called with GFP_NOIO set for the caller context in the
case of revalidate zones, and default to GFP_KERNEL for
blkdev_report_zones() unless the caller also tweaks the context memalloc
flags.

> 
> Thanks,
> 
> Bart.
> 


-- 
Damien Le Moal
Western Digital Research