Am 08.10.2018 um 18:04 hat Anton Nefedov geschrieben: > > > On 8/10/2018 6:46 PM, Kevin Wolf wrote: > > Am 08.10.2018 um 17:25 hat Anton Nefedov geschrieben: > >> > >> > >> On 8/10/2018 6:03 PM, Kevin Wolf wrote: > >>> Am 08.10.2018 um 16:38 hat Anton Nefedov geschrieben: > >>>> On 4/10/2018 6:33 PM, Kevin Wolf wrote: > >>>>> Am 21.08.2018 um 11:46 hat Anton Nefedov geschrieben: > >>>>>> Signed-off-by: Anton Nefedov <anton.nefe...@virtuozzo.com> > >>>>>> Reviewed-by: Alberto Garcia <be...@igalia.com> > >>>>>> --- > >>>>>> hw/ide/core.c | 12 ++++++++++++ > >>>>>> 1 file changed, 12 insertions(+) > >>>>>> > >>>>>> diff --git a/hw/ide/core.c b/hw/ide/core.c > >>>>>> index 2c62efc..352429b 100644 > >>>>>> --- a/hw/ide/core.c > >>>>>> +++ b/hw/ide/core.c > >>>>>> @@ -440,6 +440,14 @@ static void ide_issue_trim_cb(void *opaque, int > >>>>>> ret) > >>>>>> TrimAIOCB *iocb = opaque; > >>>>>> IDEState *s = iocb->s; > >>>>>> > >>>>>> + if (iocb->i >= 0) { > >>>>>> + if (ret >= 0) { > >>>>>> + block_acct_done(blk_get_stats(s->blk), &s->acct); > >>>>>> + } else { > >>>>>> + block_acct_failed(blk_get_stats(s->blk), &s->acct); > >>>>>> + } > >>>>>> + } > >>>>>> + > >>>>>> if (ret >= 0) { > >>>>>> while (iocb->j < iocb->qiov->niov) { > >>>>>> int j = iocb->j; > >>>>>> @@ -461,6 +469,9 @@ static void ide_issue_trim_cb(void *opaque, int > >>>>>> ret) > >>>>>> goto done; > >>>>>> } > >>>>>> > >>>>>> + block_acct_start(blk_get_stats(s->blk), &s->acct, > >>>>>> + count << BDRV_SECTOR_BITS, > >>>>>> BLOCK_ACCT_UNMAP); > >>>>>> + > >>>>>> /* Got an entry! Submit and exit. */ > >>>>>> iocb->aiocb = blk_aio_pdiscard(s->blk, > >>>>>> sector << > >>>>>> BDRV_SECTOR_BITS, > >>>>>> @@ -845,6 +856,7 @@ static void ide_dma_cb(void *opaque, int ret) > >>>>>> } > >>>>>> > >>>>>> if (ret == -EINVAL) { > >>>>>> + block_acct_invalid(blk_get_stats(s->blk), BLOCK_ACCT_UNMAP); > >>>>> > >>>>> This looks wrong to me, ide_dma_cb() is not only called for unmap, but > >>>>> also for reads and writes, and each of them could return -EINVAL. > >>>>> > >>>> > >>>> Stating here BLOCK_ACCT_UNMAP is definitely a blunder :( > >>>> > >>>>> Also, -EINVAL doesn't necessarily mean that the guest driver did > >>>>> something wrong, it could also be the result of a host problem. > >>>>> Therefore, it isn't right to call block_acct_invalid() here - especially > >>>>> since the request may already have been accounted for as either done or > >>>>> failed in ide_issue_trim_cb(). > >>>>> > >>>> > >>>> Couldn't be accounted done with such retcode; > >>>> and it seems I shouldnt do block_acct_failed() there anyway - or it's > >>>> accounted twice: there and in ide_dma_cb()->ide_handle_rw_error() > >>>> > >>>> But if EINVAL (from further layers) should not be accounted as an > >>>> invalid op, then it should be accounted failed instead, the thing that > >>>> current code does not do. > >>>> (and which brings us back to possible double-accounting if we account > >>>> invalid in ide_issue_trim_cb() ) > >>> > >>> Yes, commit caeadbc8ba4 was already wrong in assuming that there is > >>> only one possible source for -EINVAL. > >>> > >>>>> Instead, I think it would be better to immediately account for invalid > >>>>> requests in ide_issue_trim_cb() where iocb->ret = -EINVAL is set and we > >>>>> know for sure that indeed !ide_sect_range_ok() is the cause for the > >>>>> -EINVAL return code. > >>>>> > >>>> So I guess yes, move acct_invalid in ide_issue_trim_cb() and leave > >>>> acct_failed there, and filter off TRIM commands in the common > >>>> accounting. > >>> > >>> blk_aio_discard() can fail with -EINVAL, too, so getting this error code > >>> from a TRIM command doesn't mean anything. It can still have multiple > >>> possible sources. > >>> > >> > >> I meant that common ide_dma_cb() should account EINVAL (along with other > >> errors) as failed, unless it's TRIM, which means it's already > >> accounted (either invalid or failed) > > > > Oh, you would already account for failure in ide_issue_trim_cb(), too, > > but only if it's EINVAL? That feels like it would complicate the code > > quite a bit. > > > > No, no :) ide_issue_trim_cb does the proper accounting (failed/invalid) > for TRIM. > Then common path (ide_dma_cb()) does not account TRIM operations at all > regardless of the error code. No need to check for TRIM specifically if > we have BLOCK_ACCT_NONE. > > > And actually, didn't commit caeadbc8ba4 break werror=stop for requests > > returning -EINVAL because we don't call ide_handle_rw_error() any more? > > > > Yes. > > Read/write ignore werror=stop for invalid range case (not for EINVAL). > I wonder if it's crucial to ignore it for TRIM too, otherwise we could > just remove this chunk > > if (ret == -EINVAL) { > ide_dma_error(s); > return; > }
Ah, right, I forgot about this. It is actually desirable to avoid stopping for invalid requests because we should only stop for host errors. An invalid request is a guest error and stopping the VM will do nothing to fix it. (Resuming the VM would immediately fail again, so the VM would be locked in paused state.) Kevin