On 06.03.2017 05:40, NeilBrown wrote:
> On Fri, Mar 03 2017, Jack Wang wrote:
>>
>> Thanks Neil for pushing the fix.
>>
>> We can optimize generic_make_request a little bit:
>> - assign bio_list struct hold directly instead init and merge
>> - remove duplicate code
>>
>> I think better to squash into your fix.
>
> Hi Jack,
> I don't object to your changes, but I'd like to see a response from
> Jens first.
> My preference would be to get the original patch in, then other changes
> that build on it, such as this one, can be added. Until the core
> changes lands, any other work is pointless.
>
> Of course if Jens wants a this merged before he'll apply it, I'll
> happily do that.
>
> Thanks,
> NeilBrown
Hi Neil,
Totally agree, let's wait for Jens's decision.
Hi Jens,
Please consider this fix also for stable 4.3+
Thanks,
Jack Wang
>
>
>
>> ---
>> block/blk-core.c | 9 ++-------
>> 1 file changed, 2 insertions(+), 7 deletions(-)
>>
>> diff --git a/block/blk-core.c b/block/blk-core.c
>> index 3bc7202..b29b7e5 100644
>> --- a/block/blk-core.c
>> +++ b/block/blk-core.c
>> @@ -2147,8 +2147,7 @@ blk_qc_t generic_make_request(struct bio *bio)
>> struct bio_list lower, same, hold;
>>
>> /* Create a fresh bio_list for all subordinate requests
>> */
>> - bio_list_init(&hold);
>> - bio_list_merge(&hold, &bio_list_on_stack);
>> + hold = bio_list_on_stack;
>> bio_list_init(&bio_list_on_stack);
>>
>> ret = q->make_request_fn(q, bio);
>> @@ -2168,14 +2167,10 @@ blk_qc_t generic_make_request(struct bio *bio)
>> bio_list_merge(&bio_list_on_stack, &lower);
>> bio_list_merge(&bio_list_on_stack, &same);
>> bio_list_merge(&bio_list_on_stack, &hold);
>> -
>> - bio = bio_list_pop(current->bio_list);
>> } else {
>> - struct bio *bio_next = bio_list_pop(current->bio_list);
>> -
>> bio_io_error(bio);
>> - bio = bio_next;
>> }
>> + bio = bio_list_pop(current->bio_list);
>> } while (bio);
>> current->bio_list = NULL; /* deactivate */
>>
>> --
>>
>> Regards,
>> Jack
