[PATCH v3 20/20] ratelimit: Drop redundant accesses to burst

From: Paul E. McKenney
Date: Thu Apr 24 2025 - 20:31:14 EST


Now that there is the "burst <= 0" fastpath, for all later code, burst
must be strictly greater than zero. Therefore, drop the redundant checks
of this local variable.

Link: https://lore.kernel.org/all/fbe93a52-365e-47fe-93a4-44a44547d601@paulmck-laptop/
Link: https://lore.kernel.org/all/20250423115409.3425-1-spasswolf@xxxxxx/
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
Cc: Petr Mladek <pmladek@xxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx>
Cc: Mateusz Guzik <mjguzik@xxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: John Ogness <john.ogness@xxxxxxxxxxxxx>
Cc: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
---
lib/ratelimit.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/ratelimit.c b/lib/ratelimit.c
index 768f26790ea9a..626f04cabb727 100644
--- a/lib/ratelimit.c
+++ b/lib/ratelimit.c
@@ -58,7 +58,7 @@ int ___ratelimit(struct ratelimit_state *rs, const char *func)
* the current lock owner is just about to reset it.
*/
if (!raw_spin_trylock_irqsave(&rs->lock, flags)) {
- if (READ_ONCE(rs->flags) & RATELIMIT_INITIALIZED && burst &&
+ if (READ_ONCE(rs->flags) & RATELIMIT_INITIALIZED &&
atomic_read(&rs->rs_n_left) > 0 && atomic_dec_return(&rs->rs_n_left) >= 0)
ret = 1;
goto nolock_ret;
@@ -90,7 +90,7 @@ int ___ratelimit(struct ratelimit_state *rs, const char *func)
}

/* 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)
+ if (atomic_read(&rs->rs_n_left) > 0 && atomic_dec_return(&rs->rs_n_left) >= 0)
ret = 1;

unlock_ret:
--
2.40.1