Re: [PATCH] blk-throttle: Fix incorrect display of io.max

[Yu Kuai <yukuai1@xxxxxxxxxxxxxxx>]

在 2024/05/30 21:49, Waiman Long 写道:
> On 5/30/24 09:45, Waiman Long wrote:
> > Commit bf20ab538c81 ("blk-throttle: remove 
> > CONFIG_BLK_DEV_THROTTLING_LOW")
> > attempts to revert the code change introduced by commit cd5ab1b0fcb4
> > ("blk-throttle: add .low interface").  However, it leaves behind the
> > bps_conf[] and iops_conf[] fields in the throtl_grp structure which
> > aren't set anywhere in the new blk-throttle.c code but are still being
> > used by tg_prfill_limit() to display the limits in io.max. Now io.max
> > always displays the following values if a block queue is used:
> >
> >     <m>:<n> rbps=0 wbps=0 riops=0 wiops=0
> >
> > Fix this problem by removing bps_conf[] and iops_conf[] and use bps[]
> > and iops[] instead to complete the revert.
> >
> > Fixes: bf20ab538c81 ("blk-throttle: remove 
> > CONFIG_BLK_DEV_THROTTLING_LOW")
> > Reported-by: Justin Forbes <jforbes@xxxxxxxxxx>
> > Closes: 
> > https://github.com/containers/podman/issues/22701#issuecomment-2120627789
> > Signed-off-by: Waiman Long <longman@xxxxxxxxxx>

LGTM
Reviewed-by: Yu Kuai <yukuai3@xxxxxxxxxx>

> > ---
> >   block/blk-throttle.c | 24 ++++++++++++------------
> >   block/blk-throttle.h |  8 ++------
> >   2 files changed, 14 insertions(+), 18 deletions(-)
> >
> > diff --git a/block/blk-throttle.c b/block/blk-throttle.c
> > index d907040859f9..da619654f418 100644
> > --- a/block/blk-throttle.c
> > +++ b/block/blk-throttle.c
> > @@ -1347,32 +1347,32 @@ static u64 tg_prfill_limit(struct seq_file 
> > *sf, struct blkg_policy_data *pd,
> >       bps_dft = U64_MAX;
> >       iops_dft = UINT_MAX;
> > -    if (tg->bps_conf[READ] == bps_dft &&
> > -        tg->bps_conf[WRITE] == bps_dft &&
> > -        tg->iops_conf[READ] == iops_dft &&
> > -        tg->iops_conf[WRITE] == iops_dft)
> > +    if (tg->bps[READ] == bps_dft &&
> > +        tg->bps[WRITE] == bps_dft &&
> > +        tg->iops[READ] == iops_dft &&
> > +        tg->iops[WRITE] == iops_dft)
> >           return 0;
> >       seq_printf(sf, "%s", dname);
> > -    if (tg->bps_conf[READ] == U64_MAX)
> > +    if (tg->bps[READ] == U64_MAX)
> >           seq_printf(sf, " rbps=max");
> >       else
> > -        seq_printf(sf, " rbps=%llu", tg->bps_conf[READ]);
> > +        seq_printf(sf, " rbps=%llu", tg->bps[READ]);
> > -    if (tg->bps_conf[WRITE] == U64_MAX)
> > +    if (tg->bps[WRITE] == U64_MAX)
> >           seq_printf(sf, " wbps=max");
> >       else
> > -        seq_printf(sf, " wbps=%llu", tg->bps_conf[WRITE]);
> > +        seq_printf(sf, " wbps=%llu", tg->bps[WRITE]);
> > -    if (tg->iops_conf[READ] == UINT_MAX)
> > +    if (tg->iops[READ] == UINT_MAX)
> >           seq_printf(sf, " riops=max");
> >       else
> > -        seq_printf(sf, " riops=%u", tg->iops_conf[READ]);
> > +        seq_printf(sf, " riops=%u", tg->iops[READ]);
> > -    if (tg->iops_conf[WRITE] == UINT_MAX)
> > +    if (tg->iops[WRITE] == UINT_MAX)
> >           seq_printf(sf, " wiops=max");
> >       else
> > -        seq_printf(sf, " wiops=%u", tg->iops_conf[WRITE]);
> > +        seq_printf(sf, " wiops=%u", tg->iops[WRITE]);
> >       seq_printf(sf, "\n");
> >       return 0;
> > diff --git a/block/blk-throttle.h b/block/blk-throttle.h
> > index 32503fd83a84..8c365541a275 100644
> > --- a/block/blk-throttle.h
> > +++ b/block/blk-throttle.h
> > @@ -95,15 +95,11 @@ struct throtl_grp {
> >       bool has_rules_bps[2];
> >       bool has_rules_iops[2];
> > -    /* internally used bytes per second rate limits */
> > +    /* bytes per second rate limits */
> >       uint64_t bps[2];
> > -    /* user configured bps limits */
> > -    uint64_t bps_conf[2];
> > -    /* internally used IOPS limits */
> > +    /* IOPS limits */
> >       unsigned int iops[2];
> > -    /* user configured IOPS limits */
> > -    unsigned int iops_conf[2];
> >       /* Number of bytes dispatched in current slice */
> >       uint64_t bytes_disp[2];
>
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>
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