On Thu, Jul 15, 2021 at 5:36 PM Dmitry Kadashev <dkadashev@xxxxxxxxx> wrote: > > Suggested by Linus in https://lore.kernel.org/io-uring/CAHk-=wh=cpt_tQCirzFZRPawRpbuFTZ2MxNpXiyUF+eBXF=+sw@xxxxxxxxxxxxxx/ > > This patchset does all the do_* functions one by one. The idea is to > move the main logic to a helper function and handle stale retries / > struct filename cleanups outside, which makes the logic easier to > follow. > > There are a few minor changes in behavior: > > 1. filename_lookup() / filename_parentat() / filename_create() do their > own retries on ESTALE (regardless of flags), and previously they were > exempt from retries in the do_* functions (but they *were* called on > retry - it's just the return code wasn't checked for ESTALE). And > now the retry is done on the upper level, and so technically it could be > called a behavior change. Hopefully it's an edge case where an > additional check does not matter. > > 2. Some safety checks like may_mknod() / flags validation are now > repeated on retry. Those are mostly trivial and retry is a slow path, so > that should be OK. > > 3. retry_estale() is wrapped into unlikely() now > > On top of https://lore.kernel.org/io-uring/20210708063447.3556403-1-dkadashev@xxxxxxxxx/ > > v2: > > - Split flow changes and code reorganization to different commits; > > - Move more checks into the new helpers, to avoid gotos in the touched > do_* functions completely; > > - Add unlikely() around retry_estale(); > > - Name the new helper functions try_* instead of *_helper; > > Dmitry Kadashev (14): > namei: prepare do_rmdir for refactoring > namei: clean up do_rmdir retry logic > namei: prepare do_unlinkat for refactoring > namei: clean up do_unlinkat retry logic > namei: prepare do_mkdirat for refactoring > namei: clean up do_mkdirat retry logic > namei: prepare do_mknodat for refactoring > namei: clean up do_mknodat retry logic > namei: prepare do_symlinkat for refactoring > namei: clean up do_symlinkat retry logic > namei: prepare do_linkat for refactoring > namei: clean up do_linkat retry logic > namei: prepare do_renameat2 for refactoring > namei: clean up do_renameat2 retry logic > > fs/namei.c | 252 +++++++++++++++++++++++++++++------------------------ > 1 file changed, 140 insertions(+), 112 deletions(-) Ooops, the subject misses "v2", I'll resend. -- Dmitry Kadashev
