From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E72DCC43141 for ; Sat, 16 Nov 2019 11:22:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C0F8520728 for ; Sat, 16 Nov 2019 11:22:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Bn2zYLHQ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727519AbfKPLWs (ORCPT ); Sat, 16 Nov 2019 06:22:48 -0500 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:20093 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727505AbfKPLWr (ORCPT ); Sat, 16 Nov 2019 06:22:47 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1573903367; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: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=4HMm5TYaoEmQX8epqHbRRFzlwmFcGftnFt62PprOmeI=; b=Bn2zYLHQv7TpCnx00zEI0i6GdvRi3EaFwBGexwtrW8DSpL4/s0dK+z596MxGeCBK/3Bxuc tubCZ2QVib6uij/NMKgHLnrzA9RmhmSu9ZCUAdBkaS21X8eOyJXgrQOOLYRPJJXblAOXzt xiJ/2kRIyPF2TQ5pxBpznk6Ark2duUo= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-401-KXMD1hp6Pqq08ZX51F2d3g-1; Sat, 16 Nov 2019 06:22:46 -0500 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 83503107ACC4; Sat, 16 Nov 2019 11:22:44 +0000 (UTC) Received: from firesoul.localdomain (ovpn-200-41.brq.redhat.com [10.40.200.41]) by smtp.corp.redhat.com (Postfix) with ESMTP id EAEBB60142; Sat, 16 Nov 2019 11:22:43 +0000 (UTC) Received: from [192.168.42.3] (localhost [IPv6:::1]) by firesoul.localdomain (Postfix) with ESMTP id 2723F30FC134D; Sat, 16 Nov 2019 12:22:43 +0100 (CET) Subject: [net-next v2 PATCH 2/3] page_pool: add destroy attempts counter and rename tracepoint From: Jesper Dangaard Brouer Cc: Toke =?utf-8?q?H=C3=B8iland-J=C3=B8rgensen?= , netdev@vger.kernel.org, Ilias Apalodimas , Jesper Dangaard Brouer , Saeed Mahameed , Matteo Croce , Jonathan Lemon , Lorenzo Bianconi , Tariq Toukan Date: Sat, 16 Nov 2019 12:22:43 +0100 Message-ID: <157390336309.4062.14581799027142237081.stgit@firesoul> In-Reply-To: <157390333500.4062.15569811103072483038.stgit@firesoul> References: <157390333500.4062.15569811103072483038.stgit@firesoul> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-MC-Unique: KXMD1hp6Pqq08ZX51F2d3g-1 X-Mimecast-Spam-Score: 2 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable To: unlisted-recipients:; (no To-header on input) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org When Jonathan change the page_pool to become responsible to its own shutdown via deferred work queue, then the disconnect_cnt counter was removed from xdp memory model tracepoint. This patch change the page_pool_inflight tracepoint name to page_pool_release, because it reflects the new responsability better. And it reintroduces a counter that reflect the number of times page_pool_release have been tried. The counter is also used by the code, to only empty the alloc cache once. With a stuck work queue running every second and counter being 64-bit, it will overrun in approx 584 billion years. For comparison, Earth lifetime expectancy is 7.5 billion years, before the Sun will engulf, and destroy, the Earth. Signed-off-by: Jesper Dangaard Brouer Acked-by: Toke H=C3=B8iland-J=C3=B8rgensen --- include/net/page_pool.h | 2 ++ include/trace/events/page_pool.h | 9 ++++++--- net/core/page_pool.c | 13 +++++++++++-- 3 files changed, 19 insertions(+), 5 deletions(-) diff --git a/include/net/page_pool.h b/include/net/page_pool.h index 1121faa99c12..ace881c15dcb 100644 --- a/include/net/page_pool.h +++ b/include/net/page_pool.h @@ -112,6 +112,8 @@ struct page_pool { =09 * refcnt serves purpose is to simplify drivers error handling. =09 */ =09refcount_t user_cnt; + +=09u64 destroy_cnt; }; =20 struct page *page_pool_alloc_pages(struct page_pool *pool, gfp_t gfp); diff --git a/include/trace/events/page_pool.h b/include/trace/events/page_p= ool.h index 47b5ee880aa9..ee7f1aca7839 100644 --- a/include/trace/events/page_pool.h +++ b/include/trace/events/page_pool.h @@ -10,7 +10,7 @@ =20 #include =20 -TRACE_EVENT(page_pool_inflight, +TRACE_EVENT(page_pool_release, =20 =09TP_PROTO(const struct page_pool *pool, =09=09 s32 inflight, u32 hold, u32 release), @@ -22,6 +22,7 @@ TRACE_EVENT(page_pool_inflight, =09=09__field(s32,=09inflight) =09=09__field(u32,=09hold) =09=09__field(u32,=09release) +=09=09__field(u64,=09cnt) =09), =20 =09TP_fast_assign( @@ -29,10 +30,12 @@ TRACE_EVENT(page_pool_inflight, =09=09__entry->inflight=09=3D inflight; =09=09__entry->hold=09=09=3D hold; =09=09__entry->release=09=3D release; +=09=09__entry->cnt=09=09=3D pool->destroy_cnt; =09), =20 -=09TP_printk("page_pool=3D%p inflight=3D%d hold=3D%u release=3D%u", -=09 __entry->pool, __entry->inflight, __entry->hold, __entry->release) +=09TP_printk("page_pool=3D%p inflight=3D%d hold=3D%u release=3D%u cnt=3D%l= lu", +=09=09__entry->pool, __entry->inflight, __entry->hold, +=09=09__entry->release, __entry->cnt) ); =20 TRACE_EVENT(page_pool_state_release, diff --git a/net/core/page_pool.c b/net/core/page_pool.c index dfc2501c35d9..e28db2ef8e12 100644 --- a/net/core/page_pool.c +++ b/net/core/page_pool.c @@ -200,7 +200,7 @@ static s32 page_pool_inflight(struct page_pool *pool) =20 =09inflight =3D _distance(hold_cnt, release_cnt); =20 -=09trace_page_pool_inflight(pool, inflight, hold_cnt, release_cnt); +=09trace_page_pool_release(pool, inflight, hold_cnt, release_cnt); =09WARN(inflight < 0, "Negative(%d) inflight packet-pages", inflight); =20 =09return inflight; @@ -349,10 +349,13 @@ static void page_pool_free(struct page_pool *pool) =09kfree(pool); } =20 -static void page_pool_scrub(struct page_pool *pool) +static void page_pool_empty_alloc_cache_once(struct page_pool *pool) { =09struct page *page; =20 +=09if (pool->destroy_cnt) +=09=09return; + =09/* Empty alloc cache, assume caller made sure this is =09 * no-longer in use, and page_pool_alloc_pages() cannot be =09 * call concurrently. @@ -361,6 +364,12 @@ static void page_pool_scrub(struct page_pool *pool) =09=09page =3D pool->alloc.cache[--pool->alloc.count]; =09=09__page_pool_return_page(pool, page); =09} +} + +static void page_pool_scrub(struct page_pool *pool) +{ +=09page_pool_empty_alloc_cache_once(pool); +=09pool->destroy_cnt++; =20 =09/* No more consumers should exist, but producers could still =09 * be in-flight.