On Wed, Mar 29, 2023 at 11:19:35AM +0200, Peter Zijlstra wrote: > On Wed, Mar 29, 2023 at 12:51:48AM -0700, Luis Chamberlain wrote: > > On Wed, Mar 29, 2023 at 09:21:12AM +0200, Peter Zijlstra wrote: > > > On Tue, Mar 28, 2023 at 10:31:46PM -0700, Luis Chamberlain wrote: > > > > While I looked at re-using the old kernel/kmod.c (now kernel/module/kmod.c) > > > > concurrency delimiter methodology for another place in the kernel Linus > > > > noted that this could be simply replaced with a sempahore [0]. > > > > > > > > So add that so we we don't re-invent the wheel and make it obvious to use. > > > > > > > > [0] https://lore.kernel.org/all/CAHk-=whkj6=wyi201JXkw9iT_eTUTsSx+Yb9d4OgmZFjDJA18g@xxxxxxxxxxxxxx/ > > > > > > > > Suggested-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> > > > > Signed-off-by: Luis Chamberlain <mcgrof@xxxxxxxxxx> > > > > --- > > > > include/linux/semaphore.h | 3 +++ > > > > 1 file changed, 3 insertions(+) > > > > > > > > diff --git a/include/linux/semaphore.h b/include/linux/semaphore.h > > > > index 6694d0019a68..2ecdffdb9814 100644 > > > > --- a/include/linux/semaphore.h > > > > +++ b/include/linux/semaphore.h > > > > @@ -28,6 +28,9 @@ struct semaphore { > > > > #define DEFINE_SEMAPHORE(name) \ > > > > struct semaphore name = __SEMAPHORE_INITIALIZER(name, 1) > > > > > > > > +#define CONCURRENCY_LIMITER(name, n) \ > > > > + struct semaphore name = __SEMAPHORE_INITIALIZER(name, n) > > > > + > > > > > > Why should this live in semaphore.h? > > > > I have no preference, but sharing seems to have been better. Do you > > have any recommendations? > > Call is DEFINE_SEMAPHORE_N() ? > > Arguably DEFINE_SEMAPHORE() should have the argument, as binary > semaphores are a special case, but then we gotta go and fix up all > users. > > /me git-greps a little.. Hmm, not too bad. > > How's this? Seems OK to me. Either way works. Should I carry a patch from you for this series? Luis
