Re: [PATCH 3/3] scripts/make-erofs.sh: Avoid unneeded calls to mkdir

Alyssa Ross
2025-09-23T18:56:46Z

[-- Attachment #1: Type: text/plain, Size: 1987 bytes --]

Demi Marie Obenour <demiobenour@gmail.com> writes:

> On 9/23/25 10:35, Alyssa Ross wrote:
>> Demi Marie Obenour <demiobenour@gmail.com> writes:
>>
>>> On 9/21/25 14:36, Alyssa Ross wrote:
>>>> Demi Marie Obenour <demiobenour@gmail.com> writes:
>>>>
>>>>> Don't call it if the target directory already exists.
>>>>>
>>>>> Signed-off-by: Demi Marie Obenour <demiobenour@gmail.com>
>>>>> ---
>>>>> scripts/make-erofs.sh | 11 ++++++++---
>>>>> 1 file changed, 8 insertions(+), 3 deletions(-)
>>>>>
>>>>> diff --git a/scripts/make-erofs.sh b/scripts/make-erofs.sh
>>>>> index ac62a65f53e0b6417b164f475a537960fc5203bc..30b83b0b41cbe7bc4fd7786cfcdddcf10c78cc5a 100755
>>>>> --- a/scripts/make-erofs.sh
>>>>> +++ b/scripts/make-erofs.sh
>>>>> @@ -44,10 +44,15 @@ while read -r arg1; do
>>>>> # a subset of all paths, but this subset includes all of
>>>>> # the ones passed in practice other than /.
>>>>> case $arg2 in
>>>>> - (*/*) parent=${arg2%/*};;
>>>>> - (*) parent=.;;
>>>>> + (*/*)
>>>>> + # Make the parent directory if needed
>>>>> + parent=$root/${arg2%/*}
>>>>> + if [ ! -d "$parent" ]; then mkdir -p -- "$parent"; fi
>>>>> + ;;
>>>>> + (*)
>>>>> + # Parent $root which definitely exists
>>>>> + ;;
>>>>> esac
>>>>> - mkdir -p -- "$root/$parent"
>>>>> cp -RT -- "$arg1" "$root/$arg2"
>>>>> done
>>>>
>>>> I saw a statistically significant speedup in hyperfine. :)
>>>>
>>>> Reviewed-by: Alyssa Ross <hi@alyssa.is>
>>>
>>> Yay! This is independent of the rest of the series, so
>>> feel free to commit.

It actually doesn't seem to be. I get a "Permission denied" build
failure when I apply it on top of 0fcf508 ("scripts/make-erofs.sh: Avoid
calls to dirname"), but I think I didn't see that failure when I applied
patch 1 as well. We can either just keep this in the queue until we've
figured out what to do about patch 1, or you can investigate and
resubmit a standalone version of this patch. Up to you.

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 227 bytes --]