From 4b2cce999c8f5a03916b11b1e4ce192d223ab4f5 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Thu, 24 Apr 2025 12:28:24 -0700 Subject: [PATCH] ratelimit: Use nolock_ret restructuring to collapse common case code Now that unlock_ret releases the lock, then falls into nolock_ret, which handles ->missed based on the value of ret, the common-case lock-held code can be collapsed into a single "if" statement with a single-statement "then" clause. Yes, we could go further and just assign the "if" condition to ret, but in the immortal words of MSDOS, "Are you sure?". Link: https://lore.kernel.org/all/fbe93a52-365e-47fe-93a4-44a44547d601@paulmck-laptop/ Link: https://lore.kernel.org/all/20250423115409.3425-1-spasswolf@web.de/ Signed-off-by: Paul E. McKenney Reviewed-by: Petr Mladek Cc: Andrew Morton Cc: Kuniyuki Iwashima Cc: Mateusz Guzik Cc: Steven Rostedt Cc: John Ogness Cc: Sergey Senozhatsky --- lib/ratelimit.c | 13 +++---------- 1 file changed, 3 insertions(+), 10 deletions(-) diff --git a/lib/ratelimit.c b/lib/ratelimit.c index bcda7c61fc6ff..dcc063af195eb 100644 --- a/lib/ratelimit.c +++ b/lib/ratelimit.c @@ -88,17 +88,10 @@ int ___ratelimit(struct ratelimit_state *rs, const char *func) } } } - if (burst) { - int n_left = atomic_read(&rs->rs_n_left); - /* The burst might have been taken by a parallel call. */ - - if (n_left > 0) { - n_left = atomic_dec_return(&rs->rs_n_left); - if (n_left >= 0) - ret = 1; - } - } + /* Note that the burst might be taken by a parallel call. */ + if (burst && atomic_read(&rs->rs_n_left) > 0 && atomic_dec_return(&rs->rs_n_left) >= 0) + ret = 1; unlock_ret: raw_spin_unlock_irqrestore(&rs->lock, flags); -- 2.47.2