From patchwork Sat Nov 16 11:22:43 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Jesper Dangaard Brouer X-Patchwork-Id: 1196092 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.b="Bn2zYLHQ"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 47FXrT4nwpz9s4Y for ; Sat, 16 Nov 2019 22:22:49 +1100 (AEDT) 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 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 Høiland-Jørgensen --- 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 { * refcnt serves purpose is to simplify drivers error handling. */ refcount_t user_cnt; + + u64 destroy_cnt; }; 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_pool.h index 47b5ee880aa9..ee7f1aca7839 100644 --- a/include/trace/events/page_pool.h +++ b/include/trace/events/page_pool.h @@ -10,7 +10,7 @@ #include -TRACE_EVENT(page_pool_inflight, +TRACE_EVENT(page_pool_release, TP_PROTO(const struct page_pool *pool, s32 inflight, u32 hold, u32 release), @@ -22,6 +22,7 @@ TRACE_EVENT(page_pool_inflight, __field(s32, inflight) __field(u32, hold) __field(u32, release) + __field(u64, cnt) ), TP_fast_assign( @@ -29,10 +30,12 @@ TRACE_EVENT(page_pool_inflight, __entry->inflight = inflight; __entry->hold = hold; __entry->release = release; + __entry->cnt = pool->destroy_cnt; ), - TP_printk("page_pool=%p inflight=%d hold=%u release=%u", - __entry->pool, __entry->inflight, __entry->hold, __entry->release) + TP_printk("page_pool=%p inflight=%d hold=%u release=%u cnt=%llu", + __entry->pool, __entry->inflight, __entry->hold, + __entry->release, __entry->cnt) ); 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) inflight = _distance(hold_cnt, release_cnt); - trace_page_pool_inflight(pool, inflight, hold_cnt, release_cnt); + trace_page_pool_release(pool, inflight, hold_cnt, release_cnt); WARN(inflight < 0, "Negative(%d) inflight packet-pages", inflight); return inflight; @@ -349,10 +349,13 @@ static void page_pool_free(struct page_pool *pool) kfree(pool); } -static void page_pool_scrub(struct page_pool *pool) +static void page_pool_empty_alloc_cache_once(struct page_pool *pool) { struct page *page; + if (pool->destroy_cnt) + return; + /* Empty alloc cache, assume caller made sure this is * no-longer in use, and page_pool_alloc_pages() cannot be * call concurrently. @@ -361,6 +364,12 @@ static void page_pool_scrub(struct page_pool *pool) page = pool->alloc.cache[--pool->alloc.count]; __page_pool_return_page(pool, page); } +} + +static void page_pool_scrub(struct page_pool *pool) +{ + page_pool_empty_alloc_cache_once(pool); + pool->destroy_cnt++; /* No more consumers should exist, but producers could still * be in-flight.