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charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspam-User: X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 70A43100014 X-Stat-Signature: wuk1s97is8yeadkr3gfis74fibhzx1wh X-HE-Tag: 1738090246-461298 X-HE-Meta: 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 /xc9XF6I ZGhne2XOtUi+cOkUXOvy69krTG/nhGpb389j9YrRxL4b8bmI5efIAcjLXNdxmVFcrYOo/roHFj9/4kTvNDodK4bWgxYci6RpyICgU+a3fCHNZELzr/Gsl0Vp7r8EjvSxGI4LgQTMg0dCHWGZG2I2be9tEXsUOEQMiA9aIOfmbIN2KDLPkuszIxJpEJuMZuGn11cbcvGZ01F8nZzZRCgIcYvC32J1TCVWW7Xxyel+u+DBqO0VAsR13EGMH3vgNDAbLeNHwmLqLtF2chg3A+q+ZkkzypK/Qtr2CUEX2W9LY6zJz63PIxOtARksCbgJyKQ3vxvGImenhsflsjKcAifpBYgDjk6I0Zq+aAD5HI3ueuqNKMMmiOVyrT4EvJi5auPOssyTdAhp9e6BZFEg= X-Bogosity: Ham, tests=bogofilter, spamicity=0.036572, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Tue, Jan 28, 2025 at 9:21=E2=80=AFAM Sebastian Andrzej Siewior wrote: > > On 2025-01-23 19:56:52 [-0800], Alexei Starovoitov wrote: > > Usage: > > > > local_lock_t lock; // sizeof(lock) =3D=3D 0 in !RT > > local_lock_irqsave(&lock, ...); // irqsave as before > > if (local_trylock_irqsave(&lock, ...)) // compilation error > > > > local_trylock_t lock; // sizeof(lock) =3D=3D 4 in !RT > > local_lock_irqsave(&lock, ...); // irqsave and active =3D 1 > > if (local_trylock_irqsave(&lock, ...)) // if (!active) irqsave > > so I've been looking at this for a while and I don't like the part where > the type is hidden away. It is then casted back. So I tried something > with _Generics but then the existing guard implementation complained. > Then I asked myself why do we want to hide much of the implementation > and not make it obvious. Well, the idea of hiding extra field with _Generic is to avoid the churn: git grep -E 'local_.*lock_irq'|wc -l 42 I think the api is clean enough and _Generic part is not exposed to users. Misuse or accidental usage is not possible either. See the point: if (local_trylock_irqsave(&lock, ...)) // compilation error So imo it's a better tradeoff. > is this anywhere near possible to accept? Other than churn it's fine. I can go with it if you insist, but casting and _Generic() I think is cleaner. Certainly a bit unusual pattern. Could you sleep on it? I can do s/local_trylock_t/localtry_lock_t/. That part is trivial.