From mboxrd@z Thu Jan 1 00:00:00 1970 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 725A31D0956; Wed, 2 Oct 2024 14:08:02 +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=1727878082; cv=none; b=AHpWxs7qWXGwtAbfchMq/26/+e6zqHwExGMVTyWthmJfmZdzdwWoghUsAPUGZjPGGBVozsy3BU6qAVedMinLKsJSZ6Q8qSB+/RosYsLSnnhu4ivVnNCPw097t/Qw7FBwoCWye6Mmq3kug4dm9RFLoqYkxPl2OJtNDCbAsMxyONc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727878082; c=relaxed/simple; bh=ar8OiwV6/4JkkXnDI0OaYIrASnDElHa3Y5dCi9T1KMY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=saWx2ceWMu9fmgPm3AFd4qtW4UGxN/P35Mgx+Jcd6SgGT1a8GG7o9i6qUUWdVvgnotFqPjxQdVxANumJbiyRd07uyRNZolshxGmUy/QNhRM74l4h5GuJ59QWbRGQHxsc73MuG4tWjjJff+3OlSZi4e1efgYvUyToJmRC1K/uFL0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=OllS4116; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="OllS4116" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EF39CC4CEC5; Wed, 2 Oct 2024 14:08:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1727878082; bh=ar8OiwV6/4JkkXnDI0OaYIrASnDElHa3Y5dCi9T1KMY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OllS4116Q7v8lA0rtKAzG45AuVPC4bhuy9aC7cGrP7dA6YcDpX2ufqkPaGGg6uYOM rOIHgsSKYjTpw37BR+xgdnjmCZVBvkH/C8Z8D+XDNk3Ra94hiE6fZ98/crt04KldcS FhwUt+bezyuF66S93+x/WlSQaGx7/SHlmQRWYGs4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Dan Carpenter , Namhyung Kim , Adrian Hunter , Ian Rogers , Ingo Molnar , Jiri Olsa , Kan Liang , Peter Zijlstra , Arnaldo Carvalho de Melo , Sasha Levin Subject: [PATCH 6.10 295/634] perf lock contention: Change stack_id type to s32 Date: Wed, 2 Oct 2024 14:56:35 +0200 Message-ID: <20241002125822.756512082@linuxfoundation.org> X-Mailer: git-send-email 2.46.2 In-Reply-To: <20241002125811.070689334@linuxfoundation.org> References: <20241002125811.070689334@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Namhyung Kim [ Upstream commit 040c0f887fdcfe747a3f63c94e9cd29e9ed0b872 ] The bpf_get_stackid() helper returns a signed type to check whether it failed to get a stacktrace or not. But it saved the result in u32 and checked if the value is negative. 376 if (needs_callstack) { 377 pelem->stack_id = bpf_get_stackid(ctx, &stacks, 378 BPF_F_FAST_STACK_CMP | stack_skip); --> 379 if (pelem->stack_id < 0) ./tools/perf/util/bpf_skel/lock_contention.bpf.c:379 contention_begin() warn: unsigned 'pelem->stack_id' is never less than zero. Let's change the type to s32 instead. Fixes: 6d499a6b3d90277d ("perf lock: Print the number of lost entries for BPF") Reported-by: Dan Carpenter Signed-off-by: Namhyung Kim Cc: Adrian Hunter Cc: Ian Rogers Cc: Ingo Molnar Cc: Jiri Olsa Cc: Kan Liang Cc: Namhyung Kim Cc: Peter Zijlstra Link: https://lore.kernel.org/r/20240812172533.2015291-1-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin --- tools/perf/util/bpf_skel/lock_data.h | 4 ++-- tools/perf/util/bpf_skel/vmlinux/vmlinux.h | 1 + 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/tools/perf/util/bpf_skel/lock_data.h b/tools/perf/util/bpf_skel/lock_data.h index 36af11faad03c..de12892f992f8 100644 --- a/tools/perf/util/bpf_skel/lock_data.h +++ b/tools/perf/util/bpf_skel/lock_data.h @@ -7,11 +7,11 @@ struct tstamp_data { u64 timestamp; u64 lock; u32 flags; - u32 stack_id; + s32 stack_id; }; struct contention_key { - u32 stack_id; + s32 stack_id; u32 pid; u64 lock_addr_or_cgroup; }; diff --git a/tools/perf/util/bpf_skel/vmlinux/vmlinux.h b/tools/perf/util/bpf_skel/vmlinux/vmlinux.h index e9028235d7717..d818e30c54571 100644 --- a/tools/perf/util/bpf_skel/vmlinux/vmlinux.h +++ b/tools/perf/util/bpf_skel/vmlinux/vmlinux.h @@ -15,6 +15,7 @@ typedef __u8 u8; typedef __u32 u32; +typedef __s32 s32; typedef __u64 u64; typedef __s64 s64; -- 2.43.0