Re: [PATCH 0/7] minmax: reduce compilation time

Jens Axboe
2024-07-27T15:38:57Z

On 7/27/24 9:30 AM, Jens Axboe wrote:
> On 7/26/24 4:48 PM, Linus Torvalds wrote:
>> I didn't even look at what the issue was with the
>> bio_for_each_segment() expansion, in the hope that Jens will make that
>> one look better.
>
> I did take a quick look, pretty obviously bvec_iter_bvec() which makes
> it horrible, which came from Kent's immutable work quite a while ago.
> Not sure yet what to do about it, will spend some time on this next
> week.

Maybe something like this, totally untested...

diff --git a/include/linux/bvec.h b/include/linux/bvec.h
index f41c7f0ef91e..9ccccddadde2 100644
--- a/include/linux/bvec.h
+++ b/include/linux/bvec.h
@@ -130,12 +130,15 @@ struct bvec_iter_all {
(mp_bvec_iter_page((bvec), (iter)) + \
mp_bvec_iter_page_idx((bvec), (iter)))

-#define bvec_iter_bvec(bvec, iter) \
-((struct bio_vec) { \
- .bv_page = bvec_iter_page((bvec), (iter)), \
- .bv_len = bvec_iter_len((bvec), (iter)), \
- .bv_offset = bvec_iter_offset((bvec), (iter)), \
-})
+static inline struct bio_vec bvec_iter_bvec(struct bio_vec *bv,
+ struct bvec_iter iter)
+{
+ return (struct bio_vec) {
+ .bv_page = bvec_iter_page(bv, iter),
+ .bv_len = bvec_iter_len(bv, iter),
+ .bv_offset = bvec_iter_offset(bv, iter)
+ };
+}

static inline bool bvec_iter_advance(const struct bio_vec *bv,
struct bvec_iter *iter, unsigned bytes)

--
Jens Axboe