Re: [PATCH v3 00/20] Some bugfix and cleanup to mballoc

[Kemeng Shi]

on 3/4/2023 1:21 AM, Kemeng Shi wrote:
> Hi, this series contain some random cleanup patches and some bugfix
> patches to make EXT4_MB_HINT_GOAL_ONLY work properly, protect pa->pa_free
> from race and so on. More details can be found in git log.
> Thanks!
> 
> ---
> V3:
> -patch 01/20 "ext4: set goal start correctly in
> ext4_mb_normalize_request" correctly record goal in ac_g_ex instead of
> ac_f_ex, this also trigger another original bug that wanted goal maybe
> out of valid data block range. Add valid range check in patch 01/20
> to fully fix the bug.
> -run "kvm-xfstests smoke" and all tests are passed except generic/454.
> This test also failed in running kernel without this patchset, so
> it's unlikely caused by this patchset. I'm trying to figure out the
> reason but it may take a while as I'm not family with kvm-xfstests.
> Just send this series for early review and maybe some help to pass
> the failed test case.
I re-run "kvm-xfstests smoke" with newly root_fs.img and all tests pass.
It may be the early test which triggerred bug and corruptted the metadata
casues failure.
> ---
> V2:
> -Add signed-off from Ritesh and Ojaswin to patch 3/20 "ext4: get correct
> ext4_group_info in ext4_mb_prefetch_fini" as this is a duplicate of
> a patch under reviewing.
> -Split out original patch "ext4: avoid to use preallocated blocks if
> EXT4_MB_HINT_GOAL_ONLY is set" which will be resend after improved.
> -Improve log information of patch 20.
> -Collect Reviewed-by from Ojaswin and Ritesh. Now only patch 3, 12 and
> 20 need futher review.
> ---
> 
> 
> Kemeng Shi (20):
>   ext4: set goal start correctly in ext4_mb_normalize_request
>   ext4: allow to find by goal if EXT4_MB_HINT_GOAL_ONLY is set
>   ext4: get correct ext4_group_info in ext4_mb_prefetch_fini
>   ext4: correct calculation of s_mb_preallocated
>   ext4: correct start of used group pa for debug in ext4_mb_use_group_pa
>   ext4: protect pa->pa_free in ext4_discard_allocated_blocks
>   ext4: add missed brelse in ext4_free_blocks_simple
>   ext4: remove unused return value of ext4_mb_try_best_found and
>     ext4_mb_free_metadata
>   ext4: Remove unnecessary release when memory allocation failed in
>     ext4_mb_init_cache
>   ext4: remove unnecessary e4b->bd_buddy_page check in
>     ext4_mb_load_buddy_gfp
>   ext4: remove unnecessary check in ext4_mb_new_blocks
>   ext4: remove dead check in mb_buddy_mark_free
>   ext4: remove ac->ac_found > sbi->s_mb_min_to_scan dead check in
>     ext4_mb_check_limits
>   ext4: use best found when complex scan of group finishs
>   ext4: remove unnecessary exit_meta_group_info tag
>   ext4: remove unnecessary count2 in ext4_free_data_in_buddy
>   ext4: remove unnecessary goto in ext4_mb_mark_diskspace_used
>   ext4: remove repeat assignment to ac_f_ex
>   ext4: remove comment code ext4_discard_preallocations
>   ext4: simplify calculation of blkoff in ext4_mb_new_blocks_simple
> 
>  fs/ext4/mballoc.c | 111 ++++++++++++++++++----------------------------
>  1 file changed, 43 insertions(+), 68 deletions(-)
> 

-- 
Best wishes
Kemeng Shi