On Thu, Jul 27, 2023 at 09:29:11AM +0800, Kemeng Shi wrote:
>
>
> on 7/26/2023 10:50 PM, Ojaswin Mujoo wrote:
> > On Wed, Jul 26, 2023 at 02:51:06AM +0800, Kemeng Shi wrote:
> >> We named criteria with CR_XXX, correct stale comment to criteria with
> >> raw number.
> >
> > Hi Kemeng,
> >
> > Thanks for the cleanups.
> >
> >>
> >> Fixes: f52f3d2b9fba ("ext4: Give symbolic names to mballoc criterias")
> >> Signed-off-by: Kemeng Shi <shikemeng@xxxxxxxxxxxxxxx>
> >> Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@xxxxxxxxx>
> >> ---
> >> fs/ext4/mballoc.c | 8 ++++----
> >> 1 file changed, 4 insertions(+), 4 deletions(-)
> >>
> >> diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
> >> index 36eea63eaace..de5da76e6748 100644
> >> --- a/fs/ext4/mballoc.c
> >> +++ b/fs/ext4/mballoc.c
> >> @@ -2777,8 +2777,8 @@ ext4_mb_regular_allocator(struct ext4_allocation_context *ac)
> >>
> >> /*
> >> * ac->ac_2order is set only if the fe_len is a power of 2
> >> - * if ac->ac_2order is set we also set criteria to 0 so that we
> >> - * try exact allocation using buddy.
> >> + * if ac->ac_2order is set we also set criteria to CR_POWER2_ALIGNED
> >> + * so that we try exact allocation using buddy.
> >> */
> >> i = fls(ac->ac_g_ex.fe_len);
> >> ac->ac_2order = 0;
> >> @@ -2835,8 +2835,8 @@ ext4_mb_regular_allocator(struct ext4_allocation_context *ac)
> >> /*
> >> * Batch reads of the block allocation bitmaps
> >> * to get multiple READs in flight; limit
> >> - * prefetching at cr=0/1, otherwise mballoc can
> >> - * spend a lot of time loading imperfect groups
> >> + * prefetching at cr below CR_FAST, otherwise mballoc
> >
> > One of my earlier patchset has replaced the CR_FAST macro with
> > ext4_mb_cr_expensive() so maybe we can account for that here:
> >
> > https://lore.kernel.org/linux-ext4/20230630085927.140137-1-ojaswin@xxxxxxxxxxxxx/
> >
> Hi Ojaswin, sorry for missing this. I still could not find the comment update
> of stale comment "limit prefetching at cr=0/1" in that patch. Maybe we could
> update comment to "prefetching at inexpensive CR, otherwise ...". What do
> you think. Or did I miss anything.
Hey Kemeng,
That's right I missed the update but just wanted to let you know that
CR_FAST would be removed. "prefetching at inexpensive CRs, ..." sounds
good to me.
Regards,
ojaswin
>
> --
> Best wishes
> Kemeng Shi
> > Regards,
> > ojaswin
> >
> >> + * can spend a lot of time loading imperfect groups
> >
> >> */
> >> if ((prefetch_grp == group) &&
> >> (cr >= CR_FAST ||
> >> --
> >> 2.30.0
> >>
> >
>
