> [Cc Vasily]
>
> On Wed 03-11-21 21:07:03, Uladzislau Rezki wrote:
> > That extra variable has been introduced just for keeping an original
> > passed gfp_mask because it is updated with __GFP_NOWARN on entry, thus
> > error handling messages were broken.
>
> I am not sure what you mean by "error handling messages were broken"
> part.
>
We slightly discussed it in another thread :) There was __GFP_NOWARN added
on entry(unconditionally), what leads to ignoring all our internal error
messages by the warn_alloc(). I have checked the linux-next and saw that
Vasily sent a patch fixing it:
<snip>
Author: Vasily Averin <vvs@xxxxxxxxxxxxx>
Date: Thu Oct 21 15:07:26 2021 +1100
mm/vmalloc: repair warn_alloc()s in __vmalloc_area_node()
Commit f255935b9767 ("mm: cleanup the gfp_mask handling in
__vmalloc_area_node") added __GFP_NOWARN to gfp_mask unconditionally
however it disabled all output inside warn_alloc() call. This patch saves
original gfp_mask and provides it to all warn_alloc() calls.
<snip>
> It is true that the current Linus tree has a broken allocation failure
> reporting but that is not a fault of orig_gfp_mask. In fact patch which
> is fixing that "mm/vmalloc: repair warn_alloc()s in
> __vmalloc_area_node()" currently in akpm tree is adding the additional
> mask.
>
> > Instead we can keep an original gfp_mask without modifying it and add
> > an extra __GFP_NOWARN flag together with gfp_mask as a parameter to
> > the vm_area_alloc_pages() function. It will make it less confused.
>
> I would tend to agree that this is a better approach. There is already
> nested_gfp mask and one more doesn't add to the readbility.
>
Agree, that is why i decided to send a patch. Because i find that extra
gfp variable as odd one and confusing. I paid an attention on it during
our discussion about __GFP_NOFAIL. But on my tree it was not fixed at all
and after checking the linux-next i saw a fix.
>
> Maybe we should just drop the above patch and just go with one which
> doesn't introduce the intermediate step and an additional gfp mask.
>
That we can do if all agree on.
Thanks!
--
Vlad Rezki
