From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sipsolutions.net (s3.sipsolutions.net [168.119.38.16]) (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 8614D3E0C4C; Mon, 21 Sep 2026 10:15:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=168.119.38.16 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789985752; cv=none; b=Zq3Jaj82s3f8SFu8osYQ/QojKPFE34JIgSTi9WsWEYd7DKA1QDcKsCS1KAwoBQz0nSIX1eEOf1ckKUJ9Y+NiiQyLI9Ur2gDp2JtDuZ3HtdteDblAM08GvI9xN15q3nrGq90Cv6nvOxQg2558KuP6323YWGs70UJgxkRpk1sd4Ds= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789985752; c=relaxed/simple; bh=qRbo3nIagDmOVXamtI/Wqt7gq1MvSeelgCrdL3Y69hg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=UPmB7FZX+wju1DUESU4cQR7Je9+upVKWCyIIBwBW5wlhCv31AX3E28rPkGevZAbYaJc4WYi+qJflDKEsbN7kgrGB5nMfG6l1U1rl/Jc6XnuQ9nissOXy57JOpZT9Q+a2xCM7wJC4JqTBOCBk6DOhtShjRlrA7jpesHkSJxrbMOQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=permerror header.from=sipsolutions.net; spf=pass smtp.mailfrom=sipsolutions.net; dkim=pass (2048-bit key) header.d=sipsolutions.net header.i=@sipsolutions.net header.b=AHlhXWB9; arc=none smtp.client-ip=168.119.38.16 Authentication-Results: smtp.subspace.kernel.org; dmarc=permerror header.from=sipsolutions.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=sipsolutions.net Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=sipsolutions.net header.i=@sipsolutions.net header.b="AHlhXWB9" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sipsolutions.net; s=mail; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From:Content-Type:Sender :Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-To: Resent-Cc:Resent-Message-ID; bh=EDn54jabC0To4na0WfUtOppzSuDggojBsbVFmCKJPl8=; t=1789985749; x=1791195349; b=AHlhXWB9zIZ28q7r9fz6fEEUj4I3ckc1lszH9zxppcILuZP vvYdq0FfBCdCk3Cu7DGvhUDOE5Ct4qlR1+iaGO+5IEyQFdKfoIbqgw16/VS9+5VtWJqFFDSYpW+8S zq+ZFK0gLHLWwyiHt9YvfztAfTA3eHTGjqsutnp7YRvRym9q5pNmtoFDIXBrX/aIE5sLYAEHjoYxm toaibPkntMlm5h2wPlp8zfO8Wy3C27EWS2JW/pvCY55iu40BSi07jgK1zWiasBMblZpGceEliw0tn 1xqdrjlXiAbB40GMslWMXPnLOcJUEEjrFnZg7N4kI/T82ZfEtiVwqSzBmoH6pilg==; Received: by sipsolutions.net with esmtpsa (TLS1.3:ECDHE_X25519__ECDSA_SECP256R1_SHA256__AES_256_GCM:256) (Exim 4.98.2) (envelope-from ) id 1x8b3p-00000005jvH-1jqe; Mon, 21 Sep 2026 12:15:45 +0200 From: Johannes Berg To: linux-trace-kernel@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org Cc: Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers , Johannes Berg Subject: [PATCH v6 4/4] net: drop_monitor: use drop_reason_lookup() Date: Mon, 21 Sep 2026 12:06:35 +0200 Message-ID: <20260921101538.97286-10-johannes@sipsolutions.net> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260921101538.97286-6-johannes@sipsolutions.net> References: <20260921101538.97286-6-johannes@sipsolutions.net> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Johannes Berg Now that we have drop_reason_lookup(), we can just use it for drop_monitor as well, rather than exporting the list itself. Signed-off-by: Johannes Berg --- include/net/dropreason.h | 4 ---- net/core/drop_monitor.c | 20 +++++--------------- net/core/skbuff.c | 6 +++--- 3 files changed, 8 insertions(+), 22 deletions(-) diff --git a/include/net/dropreason.h b/include/net/dropreason.h index dc4a60130c09..4680da5964ef 100644 --- a/include/net/dropreason.h +++ b/include/net/dropreason.h @@ -38,10 +38,6 @@ struct drop_reason_list { size_t n_reasons; }; -/* Note: due to dynamic registrations, access must be under RCU */ -extern const struct drop_reason_list __rcu * -drop_reasons_by_subsys[SKB_DROP_REASON_SUBSYS_NUM]; - #ifdef CONFIG_TRACEPOINTS const char *drop_reason_lookup(unsigned long long value); void drop_reason_show(struct seq_file *m); diff --git a/net/core/drop_monitor.c b/net/core/drop_monitor.c index abaf108ac4db..5b685f918cc2 100644 --- a/net/core/drop_monitor.c +++ b/net/core/drop_monitor.c @@ -612,9 +612,8 @@ static int net_dm_packet_report_fill(struct sk_buff *msg, struct sk_buff *skb, size_t payload_len) { struct net_dm_skb_cb *cb = NET_DM_SKB_CB(skb); - const struct drop_reason_list *list = NULL; - unsigned int subsys, subsys_reason; char buf[NET_DM_MAX_SYMBOL_LEN]; + const char *reason_str; struct nlattr *attr; void *hdr; int rc; @@ -632,19 +631,10 @@ static int net_dm_packet_report_fill(struct sk_buff *msg, struct sk_buff *skb, goto nla_put_failure; rcu_read_lock(); - subsys = u32_get_bits(cb->reason, SKB_DROP_REASON_SUBSYS_MASK); - if (subsys < SKB_DROP_REASON_SUBSYS_NUM) - list = rcu_dereference(drop_reasons_by_subsys[subsys]); - subsys_reason = cb->reason & ~SKB_DROP_REASON_SUBSYS_MASK; - if (!list || - subsys_reason >= list->n_reasons || - !list->reasons[subsys_reason] || - strlen(list->reasons[subsys_reason]) > NET_DM_MAX_REASON_LEN) { - list = rcu_dereference(drop_reasons_by_subsys[SKB_DROP_REASON_SUBSYS_CORE]); - subsys_reason = SKB_DROP_REASON_NOT_SPECIFIED; - } - if (nla_put_string(msg, NET_DM_ATTR_REASON, - list->reasons[subsys_reason])) { + reason_str = drop_reason_lookup(cb->reason); + if (unlikely(!reason_str)) + reason_str = drop_reason_lookup(SKB_DROP_REASON_NOT_SPECIFIED); + if (nla_put_string(msg, NET_DM_ATTR_REASON, reason_str)) { rcu_read_unlock(); goto nla_put_failure; } diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 0c2d43797587..d74022457893 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -148,13 +148,11 @@ static const struct drop_reason_list drop_reasons_core = { .n_reasons = ARRAY_SIZE(drop_reasons), }; -const struct drop_reason_list __rcu * +static const struct drop_reason_list __rcu * drop_reasons_by_subsys[SKB_DROP_REASON_SUBSYS_NUM] = { [SKB_DROP_REASON_SUBSYS_CORE] = RCU_INITIALIZER(&drop_reasons_core), }; -EXPORT_SYMBOL(drop_reasons_by_subsys); -#ifdef CONFIG_TRACEPOINTS const char *drop_reason_lookup(unsigned long long value) { unsigned long long subsys_id = value >> SKB_DROP_REASON_SUBSYS_SHIFT; @@ -171,7 +169,9 @@ const char *drop_reason_lookup(unsigned long long value) return NULL; return subsys->reasons[reason]; } +EXPORT_SYMBOL(drop_reason_lookup); +#ifdef CONFIG_TRACEPOINTS void drop_reason_show(struct seq_file *m) { u32 subsys_id; -- 2.55.0