From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from SHSQR01.spreadtrum.com (unknown [222.66.158.135]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 672B1383338 for ; Tue, 12 May 2026 04:09:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=222.66.158.135 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778558985; cv=none; b=gLeFRQXsEjeBGD59H7yywMBBNHMbaLSTpiCrLot2A/Z7ey/d66M5GVKeGBonnzkguS8nOrrikRb4jQRoJScUymEXjbLUV8ju5VEXVt7sIQuBMXScGpu7XPqAiE53/AYZ2Vs5GqNkNFvBfbWqL/LQhOXQZj7qNvbGL8VLe+BHrXo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778558985; c=relaxed/simple; bh=Q3EncE/Ge5T4DIH4kRzLYf5r/zIe2RGNwkFFCQINGcA=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=JrxZBD4lpB07Gk6u1MgYiWyGIlOlDfOWBh9V5brLDAafjZeikIjnG13q8Av7ND3U+LRAvciQqM7nvFtCrx0fC3yL2gChQKBJj+5IIrTfo6/LIqKMLdGCxh7msbM8D7jMu1UaazNH1/WjznLwTjMtNW9fATVq9bm8Zzqm022pS44= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=unisoc.com; spf=pass smtp.mailfrom=unisoc.com; dkim=pass (2048-bit key) header.d=unisoc.com header.i=@unisoc.com header.b=idXOEz7Y; arc=none smtp.client-ip=222.66.158.135 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=unisoc.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=unisoc.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=unisoc.com header.i=@unisoc.com header.b="idXOEz7Y" Received: from dlp.unisoc.com ([10.29.3.86]) by SHSQR01.spreadtrum.com with ESMTP id 64C477N5006468; Tue, 12 May 2026 12:07:07 +0800 (+08) (envelope-from Yi.Sun@unisoc.com) Received: from SHDLP.spreadtrum.com (BJMBX02.spreadtrum.com [10.0.64.8]) by dlp.unisoc.com (SkyGuard) with ESMTPS id 4gF2yT6dLCz2M3YFM; Tue, 12 May 2026 12:03:45 +0800 (CST) Received: from localhost.localdomain (10.5.32.15) by BJMBX02.spreadtrum.com (10.0.64.8) with Microsoft SMTP Server (TLS) id 15.0.1497.48; Tue, 12 May 2026 12:07:04 +0800 From: Yi Sun To: , , CC: , , Subject: [PATCH 2/2] lib: bitmap: reduce the number of goto again in bitmap_find_next_zero_area_off() Date: Tue, 12 May 2026 12:06:59 +0800 Message-ID: <20260512040659.2992142-3-yi.sun@unisoc.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20260512040659.2992142-1-yi.sun@unisoc.com> References: <20260512040659.2992142-1-yi.sun@unisoc.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-ClientProxiedBy: SHCAS03.spreadtrum.com (10.0.1.207) To BJMBX02.spreadtrum.com (10.0.64.8) X-MAIL:SHSQR01.spreadtrum.com 64C477N5006468 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=unisoc.com; s=default; t=1778558843; bh=MMUyRkgmRCU5cdh+jjddYqLABEbeluyuXTP/tXDa4q8=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=idXOEz7YMIWLxT6MmCrh38Gg3+2Aru1eFcstrAw2OWT1s73FY4hoNAgOUgM1CT4XM PrN4A4m0Cy19deej7wl0jU1jEpi9dPAQOsE6CPzUraOkB/GL/R/NOUp6DCKzoOFF7O uqDN8jQbAffyg+lrNBuxqnu/rbPQhz4MtbrF/l8i5d+d72DqoynPhFE4LQl5I+ZZKw zFD+iMQNZaU3Y51Yf+uX6WslJKlxnCwao3sa+c8Cds7UVGNBg/e7LPW9aRPqszFTeD TbpShMyabeYuI/oFS24pSoiz74LRdjLqurRMcKvgJ9c2aa1a2XscxLY6N84BlguHcD bRhhNCin+nPJQ== Finding a contiguous free region in a highly fragmented bitmap is not easy and may require many repeated attempts. Therefore, find_next_bit(map, end, index) is not the optimal choice. This is because there may be multiple scattered free regions within the range [index, end) and none of them will meet the length requirement of @nr. Instead, it's sufficient to directly find the last bit within the range [index, end), thus reducing unnecessary "goto again" calls. Signed-off-by: Yi Sun --- lib/bitmap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/lib/bitmap.c b/lib/bitmap.c index b9bfa157e095..53961a7683a4 100644 --- a/lib/bitmap.c +++ b/lib/bitmap.c @@ -442,7 +442,7 @@ unsigned long bitmap_find_next_zero_area_off(unsigned long *map, end = index + nr; if (end > size) return end; - i = find_next_bit(map, end, index); + i = find_last_bit_range(map, end, index); if (i < end) { start = i + 1; goto again; -- 2.34.1