On Mon, Jan 20, 2025 at 11:42 PM Arnd Bergmann <arnd@xxxxxxxx> wrote: > > On Tue, Jan 21, 2025, at 01:19, Masahiro Yamada wrote: > > On Tue, Jan 21, 2025 at 6:29 AM Arnd Bergmann <arnd@xxxxxxxxxx> wrote: > >> > >> linux-6.12 linux-6.13 > >> ld.lld v20 1.2s 1.2s > >> ld.bfd v2.36 3.2s 5.2s > >> ld.bfd v2.39 59s 388s > >> > > > > Is this problem specific to the BFD linker from binutils? > > I only tried the bfd and lld linkers, but I assume it's limited > to the bfd one. > > > Did you observe a link speed regression with LLVM=1 build? > > No, the ld.lld line above is what I see with LLVM=1, it's > very fast (1.2s) both before and after the change. New > ld.bfd versions were much slower before the regression > for this particular config and got even slower (seven minutes > for each of the three vmlinux link stages). > Can you send me the instructions to reproduce? I'm seeing a significant performance drop (18.5x slow down) with ld.bfd v2.39 when linking linux-6.12 (i.e without this change) I will take a look at ld.bfd. It looks like an ld.bfd issue. -Rong > Arnd
