On Wed, 30 Jul 2025 11:31:35 +0200 Krzysztof Kozlowski <[email protected]> wrote:
> I pop up there a lot, but there is no confusion. I am (and maybe we are > all?) well aware that checkpatch hard limit is 100 as explained also here: > https://lore.kernel.org/all/[email protected]/ > > But the coding style still says that preferred length limit is 80. > Checkpatch is not a coding style. Coding style document is describing > the coding style... > > People trust checkpatch way too much, thus its hard limit was raised. > Some maintainers also agree with that, yet it does not invalidate what > coding style document says. Yeah, I had a couple of patches that were sent to me with everything at 100 max (comments and all). As I still have my windows set to 80 columns by default, I find it annoying. I told them to fix it and resubmit. But a break here and there where it makes it look a little better doesn't bother me. For instance, the code in kernel/trace/trace.c has: if (tif_need_resched()) trace_flags |= TRACE_FLAG_NEED_RESCHED; if (test_preempt_need_resched()) trace_flags |= TRACE_FLAG_PREEMPT_RESCHED; if (IS_ENABLED(CONFIG_ARCH_HAS_PREEMPT_LAZY) && tif_test_bit(TIF_NEED_RESCHED_LAZY)) trace_flags |= TRACE_FLAG_NEED_RESCHED_LAZY; return (trace_flags << 16) | (min_t(unsigned int, pc & 0xff, 0xf)) | (min_t(unsigned int, migration_disable_value(), 0xf)) << 4; Where if (IS_ENABLED(CONFIG_ARCH_HAS_PREEMPT_LAZY) && tif_test_bit(TIF_NEED_RESCHED_LAZY)) Breaks the 80 char limit, but honestly, I rather have that than: if (tif_need_resched()) trace_flags |= TRACE_FLAG_NEED_RESCHED; if (test_preempt_need_resched()) trace_flags |= TRACE_FLAG_PREEMPT_RESCHED; if (IS_ENABLED(CONFIG_ARCH_HAS_PREEMPT_LAZY) && tif_test_bit(TIF_NEED_RESCHED_LAZY)) trace_flags |= TRACE_FLAG_NEED_RESCHED_LAZY; return (trace_flags << 16) | (min_t(unsigned int, pc & 0xff, 0xf)) | (min_t(unsigned int, migration_disable_value(), 0xf)) << 4; As that breaks the flow. Thus, to me it's a guideline. Try to stay under 80 but we don't need to be draconian about it. -- Steve
