Re: [PATCH 4/7] sempahore: add a helper for a concurrency limiter
From: Luis Chamberlain <mcgrof@kernel.org>
Date: 2023-03-29 09:49:51
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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:quoted
On Wed, Mar 29, 2023 at 09:21:12AM +0200, Peter Zijlstra wrote:quoted
On Tue, Mar 28, 2023 at 10:31:46PM -0700, Luis Chamberlain wrote:quoted
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@mail.gmail.com/ (local) Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> --- 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