Re: [PATCH 4/4] target/rd: T10-Dif: RAM disk is allocating more space than required.

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Regards,
Quinn Tran




On 3/28/14 5:22 PM, "sagi grimberg" <sagig@xxxxxxxxxxxx> wrote:

>On 3/29/2014 2:05 AM, Quinn Tran wrote:
>> Ram disk is allocating 8x more space than required for diff data.
>> For large RAM disk test, there is small potential for memory
>> starvation.
>>
>> Signed-off-by: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>
>> Signed-off-by: Giridhar Malavali <giridhar.malavali@xxxxxxxxxx>
>> ---
>>   drivers/target/target_core_rd.c | 6 +++++-
>>   1 file changed, 5 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/target/target_core_rd.c
>>b/drivers/target/target_core_rd.c
>> index 01dda0b..6df177a 100644
>> --- a/drivers/target/target_core_rd.c
>> +++ b/drivers/target/target_core_rd.c
>> @@ -253,7 +253,11 @@ static int rd_build_prot_space(struct rd_dev
>>*rd_dev, int prot_length)
>>      if (rd_dev->rd_flags & RDF_NULLIO)
>>              return 0;
>>
>> -    total_sg_needed = rd_dev->rd_page_count / prot_length;
>> +    /* prot_length=8byte dif data
>> +     * tot sg needed = rd_page_count * (PGSZ/512) * (prot_length/PGSZ) +
>>pad
>> +     * PGSZ canceled each other.
>> +     */
>> +    total_sg_needed = (rd_dev->rd_page_count * prot_length / 512) +1;
>
>You probably will want to use block_size instead of hard-coding 512.
>Other then that this makes sense.

QT> agreed

>
>>
>>      sg_tables = (total_sg_needed / max_sg_per_table) + 1;
>>
>


________________________________

This message and any attached documents contain information from QLogic Corporation or its wholly-owned subsidiaries that may be confidential. If you are not the intended recipient, you may not read, copy, distribute, or use this information. If you have received this transmission in error, please notify the sender immediately by reply e-mail and then delete this message.
--
To unsubscribe from this list: send the line "unsubscribe target-devel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux SCSI]     [Kernel Newbies]     [Linux SCSI Target Infrastructure]     [Share Photos]     [IDE]     [Security]     [Git]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Linux ATA RAID]     [Linux IIO]     [Device Mapper]

  Powered by Linux