On Thu, Nov 12, 2020 at 4:19 PM Alexei Starovoitov <alexei.starovoitov@xxxxxxxxx> wrote: > > On Thu, Nov 12, 2020 at 4:08 PM Andrii Nakryiko > <andrii.nakryiko@xxxxxxxxx> wrote: > > > > So I looked at your vmlinux image. I think we should just keep > > everything mostly as it it right now (without changes in this patch), > > but add just two simple checks: > > > > 1. Skip if fn->declaration (ignore correctly marked func declarations) > > 2. Skip if DW_AT_inline: 1 (ignore inlined functions). > > > > I'd keep the named arguments check as is, I think it's helpful. 1) > > will skip stuff that's explicitly marked as declaration. 2) inline > > check will partially mitigate dropping of fn->external check (and we > > can't really attach to inlined functions). > > I thought DW_AT_inline is an indication that the function was marked "inline" > in C code. That doesn't mean that the function was actually inlined. > So I don't think pahole should check that bit. According to DWARF spec, there are 4 possible values: DW_INL_not_inlined = 0 Not declared inline nor inlined by the compiler DW_INL_inlined = 1 Not declared inline but inlined by the compiler DW_INL_declared_not_inlined = 2 Declared inline but not inlined by the compiler DW_INL_declared_inlined = 3 Declared inline and inlined by the compiler So DW_INL_inlined is supposed to be added to functions that are not marked inline, but were nevertheless inlined. I saw this for one of vfs_getattr entries in DWARF, which clearly is not marked inline. But also that DWARF entry had proper args with names, so it would work fine as well. I don't know, with DWARF it's always some guessing game. Let's leave DW_AT_inline alone for now. Important part is skipping declarations (when they are marked as such), though I'm not claiming it will solve the problem completely... :)
