From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from gandalf.ozlabs.org (gandalf.ozlabs.org [150.107.74.76]) by passt.top (Postfix) with ESMTPS id CCAB55A0272 for ; Thu, 21 Dec 2023 07:16:01 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gibson.dropbear.id.au; s=202312; t=1703139352; bh=2hNoO017Szfr1hsVBqlFRHfKdQUo8kdsDOJDnFRvB9k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=boo8Hmi7UjcqCryE+sn2zhNh3rdN9kzLhtKwibs4XbI69/LWhmHnz9N1BL513CWgP ZsFx2OCJCmQtawUMxWApIgBhM3fHfBaUjCEtAaQlV1nLDhlDoXlzGGhB6j0KPUntoV lGajIq5aT1iaAsqy5YHHg3FVbmT8V87l5ofuR2oJjzd+hpHVoMuDpyIw5F/iyYs4l4 0eRoRP13nUgVqaeHXh6Lmhuy/xDGYKjMSzjILj/uLAiPhQrROcfiZv4UDZBIaSp9ZJ mpX8zrBMEu5hyWepChiSGSTFqC4EwQ0WTLgGNrsdOb8Is602mYVBV+iZcsX7wdacRs yyKowdJ0Vrq+Q== Received: by gandalf.ozlabs.org (Postfix, from userid 1007) id 4SwgCr4m4fz4xR5; Thu, 21 Dec 2023 17:15:52 +1100 (AEDT) From: David Gibson To: passt-dev@passt.top, Stefano Brivio Subject: [PATCH v3 12/13] flow: Enforce that freeing of closed flows must happen in deferred handlers Date: Thu, 21 Dec 2023 17:15:48 +1100 Message-ID: <20231221061549.976358-13-david@gibson.dropbear.id.au> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20231221061549.976358-1-david@gibson.dropbear.id.au> References: <20231221061549.976358-1-david@gibson.dropbear.id.au> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Message-ID-Hash: E2AUYRH7Y6YTW3BSDJO2PS5KXHIPIDP4 X-Message-ID-Hash: E2AUYRH7Y6YTW3BSDJO2PS5KXHIPIDP4 X-MailFrom: dgibson@gandalf.ozlabs.org X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: David Gibson X-Mailman-Version: 3.3.8 Precedence: list List-Id: Development discussion and patches for passt Archived-At: Archived-At: List-Archive: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: Currently, flows are only evern finally freed (and the table compacted) from the deferred handlers. Some future ways we want to optimise managing the flow table will rely on this, so enforce it: rather than having the TCP code directly call flow_table_compact(), add a boolean return value to the per-flow deferred handlers. If true, this indicates that the flow code itself should free the flow. This forces all freeing of flows to occur during the flow code's scan of the table in flow_defer_handler() which opens possibilities for future optimisations. Signed-off-by: David Gibson --- flow.c | 13 +++++++++---- flow.h | 1 - tcp.c | 9 +++++---- tcp_conn.h | 4 ++-- tcp_splice.c | 9 +++++---- 5 files changed, 21 insertions(+), 15 deletions(-) diff --git a/flow.c b/flow.c index 8fbe512..7b99b58 100644 --- a/flow.c +++ b/flow.c @@ -80,7 +80,7 @@ void flow_alloc_cancel(union flow *flow) * @c: Execution context * @hole: Pointer to recently closed flow */ -void flow_table_compact(const struct ctx *c, union flow *hole) +static void flow_table_compact(const struct ctx *c, union flow *hole) { union flow *from; @@ -130,18 +130,23 @@ void flow_defer_handler(const struct ctx *c, const struct timespec *now) } for (flow = flowtab + flow_count - 1; flow >= flowtab; flow--) { + bool closed = false; + switch (flow->f.type) { case FLOW_TCP: - tcp_flow_defer(c, flow); + closed = tcp_flow_defer(flow); break; case FLOW_TCP_SPLICE: - tcp_splice_flow_defer(c, flow); - if (timer) + closed = tcp_splice_flow_defer(flow); + if (!closed && timer) tcp_splice_timer(c, flow); break; default: /* Assume other flow types don't need any handling */ ; } + + if (closed) + flow_table_compact(c, flow); } } diff --git a/flow.h b/flow.h index 44058bf..8064f0e 100644 --- a/flow.h +++ b/flow.h @@ -68,7 +68,6 @@ static inline bool flow_sidx_eq(flow_sidx_t a, flow_sidx_t b) union flow; -void flow_table_compact(const struct ctx *c, union flow *hole); void flow_defer_handler(const struct ctx *c, const struct timespec *now); void flow_log_(const struct flow_common *f, int pri, const char *fmt, ...) diff --git a/tcp.c b/tcp.c index 6477203..a38deb0 100644 --- a/tcp.c +++ b/tcp.c @@ -1303,21 +1303,22 @@ static struct tcp_tap_conn *tcp_hash_lookup(const struct ctx *c, /** * tcp_flow_defer() - Deferred per-flow handling (clean up closed connections) - * @c: Execution context * @flow: Flow table entry for this connection + * + * Return: true if the flow is ready to free, false otherwise */ -void tcp_flow_defer(const struct ctx *c, union flow *flow) +bool tcp_flow_defer(union flow *flow) { const struct tcp_tap_conn *conn = &flow->tcp; if (flow->tcp.events != CLOSED) - return; + return false; close(conn->sock); if (conn->timer != -1) close(conn->timer); - flow_table_compact(c, flow); + return true; } static void tcp_rst_do(struct ctx *c, struct tcp_tap_conn *conn); diff --git a/tcp_conn.h b/tcp_conn.h index 825155a..636224e 100644 --- a/tcp_conn.h +++ b/tcp_conn.h @@ -158,8 +158,8 @@ extern int init_sock_pool6 [TCP_SOCK_POOL_SIZE]; void tcp_tap_conn_update(const struct ctx *c, struct tcp_tap_conn *old, struct tcp_tap_conn *new); void tcp_splice_conn_update(const struct ctx *c, struct tcp_splice_conn *new); -void tcp_flow_defer(const struct ctx *c, union flow *flow); -void tcp_splice_flow_defer(const struct ctx *c, union flow *flow); +bool tcp_flow_defer(union flow *flow); +bool tcp_splice_flow_defer(union flow *flow); void tcp_splice_timer(const struct ctx *c, union flow *flow); int tcp_conn_pool_sock(int pool[]); int tcp_conn_new_sock(const struct ctx *c, sa_family_t af); diff --git a/tcp_splice.c b/tcp_splice.c index 18cd2e6..0711b19 100644 --- a/tcp_splice.c +++ b/tcp_splice.c @@ -244,16 +244,17 @@ void tcp_splice_conn_update(const struct ctx *c, struct tcp_splice_conn *new) /** * tcp_splice_flow_defer() - Deferred per-flow handling (clean up closed) - * @c: Execution context * @flow: Flow table entry for this connection + * + * Return: true if the flow is ready to free, false otherwise */ -void tcp_splice_flow_defer(const struct ctx *c, union flow *flow) +bool tcp_splice_flow_defer(union flow *flow) { struct tcp_splice_conn *conn = &flow->tcp_splice; unsigned side; if (!(flow->tcp_splice.flags & CLOSING)) - return; + return false; for (side = 0; side < SIDES; side++) { if (conn->events & SPLICE_ESTABLISHED) { @@ -277,7 +278,7 @@ void tcp_splice_flow_defer(const struct ctx *c, union flow *flow) conn->flags = 0; flow_dbg(conn, "CLOSED"); - flow_table_compact(c, flow); + return true; } /** -- 2.43.0