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 2C8912E2EF3; Sat, 20 Sep 2025 01:00:15 +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=1758330015; cv=none; b=LgauLlpk8wIlCUf8vC3Iu/VXQbCow5Rvh9AapymV1UJV533IcKnUrbLx4w48XS52ZiaoPtBeEqzDTzqNZPJEhELE5SrpgEQTo2reYTf88b2CWG+8aezf/gSlUFW3odBRA+zKGhUqaZbw9cUBLh7vUCNUqlNTnN8fRq0SY0CaQf8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758330015; c=relaxed/simple; bh=DGypOrq6SgMS5tci1mp5f1brFYetegLf2MZV9KNNQoY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=tomVUk+EI7Ix46QkBDM4pm3F1HaExbKM3WQCPbDjWLn0GsEpuGn7e/K362zFg09YRxZPH95Wjeo6vEZgiPsIqisiRwpkgK79F/mQ90I3D/v/rIcogOgdbcarJff7gBNhtQGtycr5MInw7kkfsQ+wEyMwCRKGICICUIV9x/+9mY4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=kptV9WJu; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="kptV9WJu" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E77A4C4CEF0; Sat, 20 Sep 2025 01:00:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1758330015; bh=DGypOrq6SgMS5tci1mp5f1brFYetegLf2MZV9KNNQoY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kptV9WJuFmHdptVHV8UaYL7QoRKxw6xpkvTufWVBBu170zwLBfuTF4WfGlttUT2Is JgtMaZIIDUvL05jNbxjk2a5yz8BlRlnv1KMLmCMe8NfkIlrXa0SaI/M0mVYLy0jZ/x NUrI0jvIRbwpr/Gl5h93EhlDmt4Ur7aws+8B7SRWvVOFCOnh2Dh/BofxOPiqYmIImK QmNX9vzSWthWS90tWxdxJ2tpMlYs0rJBKovSal25Cud2ywYlDaMTjxnTEQup4lgilv TSH40taBhMFCMv742sXsno5ryUjbPfqh2rIsdoW/+BqJDA4I2s8Qguqhg/WN5sOqqD jU28iYnKC8QgA== From: Tejun Heo To: void@manifault.com, arighi@nvidia.com, multics69@gmail.com Cc: linux-kernel@vger.kernel.org, sched-ext@lists.linux.dev, memxor@gmail.com, bpf@vger.kernel.org, Tejun Heo Subject: [PATCH 38/46] sched_ext: Convert scx_dump_state() spinlock to raw spinlock Date: Fri, 19 Sep 2025 14:59:01 -1000 Message-ID: <20250920005931.2753828-39-tj@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20250920005931.2753828-1-tj@kernel.org> References: <20250920005931.2753828-1-tj@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit The scx_dump_state() function uses a regular spinlock to serialize access. In a subsequent patch, this function will be called while holding scx_sched_lock, which is a raw spinlock, creating a lock nesting violation. Convert the dump_lock to a raw spinlock and use the guard macro for cleaner lock management. Signed-off-by: Tejun Heo --- kernel/sched/ext.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c index 4dc82afb7016..fafffe3ee812 100644 --- a/kernel/sched/ext.c +++ b/kernel/sched/ext.c @@ -4565,7 +4565,7 @@ static void scx_dump_task(struct seq_buf *s, struct scx_dump_ctx *dctx, static void scx_dump_state(struct scx_exit_info *ei, size_t dump_len) { - static DEFINE_SPINLOCK(dump_lock); + static DEFINE_RAW_SPINLOCK(dump_lock); static const char trunc_marker[] = "\n\n~~~~ TRUNCATED ~~~~\n"; struct scx_sched *sch = scx_root; struct scx_dump_ctx dctx = { @@ -4577,11 +4577,10 @@ static void scx_dump_state(struct scx_exit_info *ei, size_t dump_len) }; struct seq_buf s; struct scx_event_stats events; - unsigned long flags; char *buf; int cpu; - spin_lock_irqsave(&dump_lock, flags); + guard(raw_spinlock_irqsave)(&dump_lock); seq_buf_init(&s, ei->dump, dump_len); @@ -4705,8 +4704,6 @@ static void scx_dump_state(struct scx_exit_info *ei, size_t dump_len) if (seq_buf_has_overflowed(&s) && dump_len >= sizeof(trunc_marker)) memcpy(ei->dump + dump_len - sizeof(trunc_marker), trunc_marker, sizeof(trunc_marker)); - - spin_unlock_irqrestore(&dump_lock, flags); } static void scx_error_irq_workfn(struct irq_work *irq_work) -- 2.51.0