sempahore: add a helper for a concurrency limiter
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.
While at it, add some tribal knowledge about why some existing binary
semaphores are not converted to mutexes today.
[0] https://lore.kernel.org/all/CAHk-=whkj6=wyi201JXkw9iT_eTUTsSx+Yb9d4OgmZFjDJA18g@mail.gmail.com/
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
1 file changed
