Hi,
在 2025/02/11 21:57, Michal Koutný 写道:
Hello Linxuan.
On Mon, Feb 10, 2025 at 11:18:27AM +0800, Chen Linxuan <chenlinxuan@xxxxxxxxxxxxx> wrote:
Move the validation check for cpd/pd_alloc_fn and cpd/pd_free_fn function
pairs to the start of blkcg_policy_register(). This ensures we immediately
return -EINVAL if the function pairs are not correctly provided, rather
than returning -ENOSPC after locking and unlocking mutexes unnecessarily.
Co-authored-by: Wen Tao <wentao@xxxxxxxxxxxxx>
Signed-off-by: Wen Tao <wentao@xxxxxxxxxxxxx>
Signed-off-by: Chen Linxuan <chenlinxuan@xxxxxxxxxxxxx>
If you consider those locks contention a problem (policy registrations
are "only" boot time, possibly module load time), then it's good to refer
Fixes: e84010732225c ("blkcg: add sanity check for blkcg policy operations")
This is super cold path, so I don't think it's a problem.
---
block/blk-cgroup.c | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)
But it's correct,
Reviewed-by: Michal Koutný <mkoutny@xxxxxxxx>
Since we're here, can you also change the return value to -ENOMEM from
error path err_free_cpds?
Thanks,
Kuai
