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Message-Id: <1406558925-24060-1-git-send-email-linux@rasmusvillemoes.dk> Date: Mon, 28 Jul 2014 16:48:45 +0200 From: Rasmus Villemoes <linux@...musvillemoes.dk> To: Thomas Gleixner <tglx@...utronix.de> Cc: linux-kernel@...r.kernel.org, Rasmus Villemoes <linux@...musvillemoes.dk> Subject: [PATCH] kernel: timer.c: Small improvement in apply_slack() In apply_slack(), find_last_bit() is applied to a bitmask consisting of precisely BITS_PER_LONG bits. Since mask is non-zero, we might as well eliminate the function call and use __fls() directly. On x86_64, this shaves 22 bytes of the only caller, mod_timer(). Found through Coverity CID 1192106, but that is a false positive, since Coverity is not aware that mask != 0 implies that find_last_bit will not return BITS_PER_LONG. Signed-off-by: Rasmus Villemoes <linux@...musvillemoes.dk> --- kernel/timer.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/timer.c b/kernel/timer.c index 3bb01a3..b7d1a1e 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -836,7 +836,7 @@ unsigned long apply_slack(struct timer_list *timer, unsigned long expires) if (mask == 0) return expires; - bit = find_last_bit(&mask, BITS_PER_LONG); + bit = __fls(mask); mask = (1UL << bit) - 1; -- 1.9.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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