From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by passt.top (Postfix) with ESMTP id 431895A026D for ; Sat, 6 Jan 2024 17:00:01 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1704556800; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=tC9RJ5ut34jgPyyXBZ8OwMl9irrA0vIsihGNDw0DwlA=; b=F1eSE1r9Q3FqNvnJzZa16L6H5DUFh1HcgYbct52RHc5A/Uj6eq9ajftO8vUx/1jvOjVgX2 /oTPwPCa3quBpTK0CQvXBQhVRoDbGyZihMy3UHNFvIVv8EdiiTbhwdYnS8ZwU8Ik/geEPK jHykvJQn492hUU6s+2itchhpHawYk+0= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-297-vwqVjaWUMAWq0tyKQd6r-w-1; Sat, 06 Jan 2024 10:59:56 -0500 X-MC-Unique: vwqVjaWUMAWq0tyKQd6r-w-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 5CEFA1019DE1; Sat, 6 Jan 2024 15:59:56 +0000 (UTC) Received: from elisabeth (unknown [10.39.208.16]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 88A28C15968; Sat, 6 Jan 2024 15:59:55 +0000 (UTC) Date: Sat, 6 Jan 2024 16:59:53 +0100 From: Stefano Brivio To: David Gibson Subject: Re: [PATCH v2 07/12] icmp: Simplify socket expiry scanning Message-ID: <20240106165953.639cb7aa@elisabeth> In-Reply-To: <20231221065327.1307827-8-david@gibson.dropbear.id.au> References: <20231221065327.1307827-1-david@gibson.dropbear.id.au> <20231221065327.1307827-8-david@gibson.dropbear.id.au> Organization: Red Hat MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.8 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Message-ID-Hash: H6GKXXQOG5EZQR2FMXB7TZXHLE7EKURE X-Message-ID-Hash: H6GKXXQOG5EZQR2FMXB7TZXHLE7EKURE X-MailFrom: sbrivio@redhat.com 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: passt-dev@passt.top 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: On Thu, 21 Dec 2023 17:53:22 +1100 David Gibson wrote: > Currently we use icmp_act[] to scan for ICMP ids which might have an open > socket which could time out. However icmp_act[] contains no information > that's not already in icmp_id_map[] - it's just an "index" which allows > scanning for relevant entries with less cache footprint. > > We only scan for ICMP socket expiry every 1s, though, so it's not clear > that cache footprint really matters. Furthermore, there's no strong reason > we need to scan even that often - the timeout is fairly arbitrary and > approximate. > > So, eliminate icmp_act[] in favour of directly scanning icmp_id_map[] and > compensate for the cache impact by reducing the scan frequency to once > every 10s. > > Signed-off-by: David Gibson > --- > icmp.c | 34 ++++++---------------------------- > icmp.h | 2 +- > 2 files changed, 7 insertions(+), 29 deletions(-) > > diff --git a/icmp.c b/icmp.c > index dd98c7f..02739b9 100644 > --- a/icmp.c > +++ b/icmp.c > @@ -56,9 +56,6 @@ struct icmp_id_sock { > /* Indexed by ICMP echo identifier */ > static struct icmp_id_sock icmp_id_map[IP_VERSIONS][ICMP_NUM_IDS]; > > -/* Bitmaps, activity monitoring needed for identifier */ > -static uint8_t icmp_act[IP_VERSIONS][DIV_ROUND_UP(ICMP_NUM_IDS, 8)]; > - > /** > * icmp_sock_handler() - Handle new data from IPv4 ICMP socket > * @c: Execution context > @@ -194,7 +191,6 @@ int icmp_tap_handler(const struct ctx *c, uint8_t pif, int af, > debug("ICMP: new socket %i for echo ID %i", s, id); > } > icmp_id_map[V4][id].ts = now->tv_sec; > - bitmap_set(icmp_act[V4], id); > > sa.sin_addr = *(struct in_addr *)daddr; > if (sendto(s, ih, sizeof(*ih) + plen, MSG_NOSIGNAL, > @@ -237,7 +233,6 @@ int icmp_tap_handler(const struct ctx *c, uint8_t pif, int af, > debug("ICMPv6: new socket %i for echo ID %i", s, id); > } > icmp_id_map[V6][id].ts = now->tv_sec; > - bitmap_set(icmp_act[V6], id); > > sa.sin6_addr = *(struct in6_addr *)daddr; > if (sendto(s, ih, sizeof(*ih) + plen, MSG_NOSIGNAL, > @@ -261,20 +256,15 @@ fail_sock: > /** > * icmp_timer_one() - Handler for timed events related to a given identifier > * @c: Execution context > - * @v6: Set for IPv6 echo identifier bindings > - * @id: Echo identifier, host order > + * @id_map: id socket information to check timers for It took me a few readings to understand this... what about: * @id_sock: Socket number and activity timestamp ? -- Stefano