From patchwork Tue Jun 4 14:41:25 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Rostedt X-Patchwork-Id: 13685465 X-Patchwork-Delegate: bpf@iogearbox.net 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 8D71F14A096; Tue, 4 Jun 2024 14:42:18 +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=1717512138; cv=none; b=Eptt4UD/3JD0af5pIbHEcpraagddzwbwfunwR26yWATB3jhCH/6qtGFJQ5c68KmS+OGk2aFKjogvtYyeLvhuvnDG+7eXBUnynISIXfObUty9pDNB6mnIb3H5F7uXW7wJRYJkTOeDMU9pMGavh/j0urRDXnoC2nle17v3dg/GlIY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717512138; c=relaxed/simple; bh=tawZq6mZMuTEGrptN7vmtsKrb6RsFVEDkjhbdYbPgqc=; h=Message-ID:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=QwFdypVtfESp1t5ZRjPQcA3rMaAHt4YFYfNHTIqhygeKECd17aU4GvogqpZjHdjgS52HPUBLhLZkDy+XZMflr6alg45NoTG+NtX1W21rEWI2r/Jxwe0YULd1USWMvLkIrokqoLv4tC4gE2RnA8dm+9LeycUvDwy+aHE16oh8L1E= 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 75A14C2BBFC; Tue, 4 Jun 2024 14:42:18 +0000 (UTC) Received: from rostedt by gandalf with local (Exim 4.97) (envelope-from ) id 1sEVMf-00000000Z3z-2kN0; Tue, 04 Jun 2024 10:42:17 -0400 Message-ID: <20240604144217.514766673@goodmis.org> User-Agent: quilt/0.68 Date: Tue, 04 Jun 2024 10:41:25 -0400 From: Steven Rostedt To: linux-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: [for-next][PATCH 22/27] function_graph: Use for_each_set_bit() in __ftrace_return_to_handler() References: <20240604144103.293353991@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. Link: https://lore.kernel.org/linux-trace-kernel/20240603190824.447448026@goodmis.org Cc: Mark Rutland Cc: Mathieu Desnoyers Cc: Andrew Morton Cc: Alexei Starovoitov Cc: Florent Revest Cc: Martin KaFai Lau Cc: bpf Cc: Sven Schnelle Cc: Alexei Starovoitov Cc: Jiri Olsa Cc: Arnaldo Carvalho de Melo Cc: Daniel Borkmann Cc: Alan Maguire Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Guo Ren 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;