From patchwork Mon Jun 3 19:07:26 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Rostedt X-Patchwork-Id: 13684173 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 ADDD113CFA4; Mon, 3 Jun 2024 19:07:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717441633; cv=none; b=o7WLjfFgrQcRri8qtdR72REC1jvooz3z+9zzw6H8GhY+XvUO3FR2nn0Xc5icV26IjVaVyqpEmd1ZOGhR/rbQ9IcNnl85GyWvVR4naUQjcORrdczB2IZkKI//VBX2B8RCwwmiEcg1OQ/RU7MiahARPtZcg6WI944Xx1eNMKLZNHk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717441633; c=relaxed/simple; bh=HaOqVX9Zfq8EcxlqcgeTv6riQSn0DAcVMNqbadp2eeM=; h=Message-ID:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=rKg9hctxxEGKAmGRDo0lGA3owFq4gikhwiEJ1eB0EuCJvsLi3+nnRJxJfHkbPd2kkEi8TIv4ZjgnS8Z3iPvHWX/sVydy864XjjhQ7SDNIRA+7ECjZHUZRvzni+ivAfuhdNSwgqvTnwnZy5GdsJ6+LaB4SSV5NOHxPgrE4IgT5jE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8B5B8C4AF0D; Mon, 3 Jun 2024 19:07:13 +0000 (UTC) Received: from rostedt by gandalf with local (Exim 4.97) (envelope-from ) id 1sED2e-00000009Twx-2Rbe; Mon, 03 Jun 2024 15:08:24 -0400 Message-ID: <20240603190824.447448026@goodmis.org> User-Agent: quilt/0.68 Date: Mon, 03 Jun 2024 15:07:26 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Cc: Masami Hiramatsu , Mark Rutland , Mathieu Desnoyers , Andrew Morton , Alexei Starovoitov , Florent Revest , Martin KaFai Lau , bpf , Sven Schnelle , Alexei Starovoitov , Jiri Olsa , Arnaldo Carvalho de Melo , Daniel Borkmann , Alan Maguire , Peter Zijlstra , Thomas Gleixner , Guo Ren Subject: [PATCH v3 22/27] function_graph: Use for_each_set_bit() in __ftrace_return_to_handler() References: <20240603190704.663840775@goodmis.org> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: "Steven Rostedt (Google)" Instead of iterating through the entire fgraph_array[] and seeing if one of the bitmap bits are set to know to call the array's retfunc() function, use for_each_set_bit() on the bitmap itself. This will only iterate for the number of set bits. Reviewed-by: Masami Hiramatsu (Google) Signed-off-by: Steven Rostedt (Google) --- kernel/trace/fgraph.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/kernel/trace/fgraph.c b/kernel/trace/fgraph.c index f207b7ae5f46..0827b67f746d 100644 --- a/kernel/trace/fgraph.c +++ b/kernel/trace/fgraph.c @@ -783,11 +783,10 @@ static unsigned long __ftrace_return_to_handler(struct fgraph_ret_regs *ret_regs #endif bitmap = get_bitmap_bits(current, offset); - for (i = 0; i < FGRAPH_ARRAY_SIZE; i++) { + + for_each_set_bit(i, &bitmap, sizeof(bitmap) * BITS_PER_BYTE) { struct fgraph_ops *gops = fgraph_array[i]; - if (!(bitmap & BIT(i))) - continue; if (gops == &fgraph_stub) continue;