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=-2.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED, USER_AGENT_MUTT 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 8E5DBC43387 for ; Thu, 17 Jan 2019 13:10:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5C9BA20652 for ; Thu, 17 Jan 2019 13:10:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="AGkkCO8w" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728135AbfAQNJ7 (ORCPT ); Thu, 17 Jan 2019 08:09:59 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:57542 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728078AbfAQNJ5 (ORCPT ); Thu, 17 Jan 2019 08:09:57 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=F9lFvUgpC9otS0kOpoLTOT92XFf/uctbZHhmkIFvays=; b=AGkkCO8wC7fd5bZ1dJw9TbzLG b1Xs0DC4ml0fkIW+B6m6HhGIOOEoCky3dktXr2Ptm8Y7GjXXenNZ+wAOR04BMbReInTnOKlScUqye c1kTBnK6PvkWpRgbPvWdkBhEUGc4FHoO+k1ZOSkDCcGkKjOMPppD1SuXUKy3z6Q718cY7LKSTQkKa Q/Um92B35f8KguZ3gR6gSg7mRHqQ7Tjg20gfdH2K+eKxh3C+IT0bZRtVJpuEfGvCrW1q+qj9R7UwF VTprqBfse6slKD/ALK8+YcCZNg26ocEu0MgNAgY69LAiJvw6BuTHIw3i2CKij435cP4WW83YtJ+p/ 9onYOXaLw==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1gk7Qg-0006NI-FL; Thu, 17 Jan 2019 13:09:54 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id E9753202647CE; Thu, 17 Jan 2019 14:09:52 +0100 (CET) Date: Thu, 17 Jan 2019 14:09:52 +0100 From: Peter Zijlstra To: Song Liu Cc: linux-kernel@vger.kernel.org, netdev@vger.kernel.org, acme@kernel.org, ast@kernel.org, daniel@iogearbox.net, kernel-team@fb.com, dsahern@gmail.com Subject: Re: [PATCH v10 perf, bpf-next 3/9] perf, bpf: introduce PERF_RECORD_BPF_EVENT Message-ID: <20190117130952.GG10486@hirez.programming.kicks-ass.net> References: <20190116162931.1542429-1-songliubraving@fb.com> <20190116162931.1542429-4-songliubraving@fb.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190116162931.1542429-4-songliubraving@fb.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jan 16, 2019 at 08:29:25AM -0800, Song Liu wrote: > + /* > + * Record bpf events: > + * enum perf_bpf_event_type { > + * PERF_BPF_EVENT_UNKNOWN = 0, > + * PERF_BPF_EVENT_PROG_LOAD = 1, > + * PERF_BPF_EVENT_PROG_UNLOAD = 2, > + * }; > + * > + * struct { > + * struct perf_event_header header; > + * u16 type; > + * u16 flags; > + * u32 id; > + * u8 tag[BPF_TAG_SIZE]; This does forever fix BPF_TAG_SIZE; is that intentional? We could easily make that a variable length field like with the other event. Or is that value already part of the eBPF ABI? > + * struct sample_id sample_id; > + * }; > + */ > + PERF_RECORD_BPF_EVENT = 18, > @@ -7744,6 +7747,121 @@ void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len, bool unregister, > WARN_ONCE(1, "%s: Invalid KSYMBOL type 0x%x\n", __func__, ksym_type); > } > > +struct perf_bpf_event { > + struct bpf_prog *prog; > + struct { > + struct perf_event_header header; > + u16 type; > + u16 flags; > + u32 id; > + u8 tag[BPF_TAG_SIZE]; > + } event_id; > +}; > +static void perf_event_bpf_emit_ksymbols(struct bpf_prog *prog, > + enum perf_bpf_event_type type) > +{ > + bool unregister = type == PERF_BPF_EVENT_PROG_UNLOAD; > + int i; > + > + if (prog->aux->func_cnt == 0) { > + perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_BPF, > + (u64)(unsigned long)prog->bpf_func, > + prog->jited_len, unregister, > + perf_event_bpf_get_name, prog); > + } else { > + for (i = 0; i < prog->aux->func_cnt; i++) { > + struct bpf_prog *subprog = prog->aux->func[i]; > + > + perf_event_ksymbol( > + PERF_RECORD_KSYMBOL_TYPE_BPF, > + (u64)(unsigned long)subprog->bpf_func, > + subprog->jited_len, unregister, > + perf_event_bpf_get_name, subprog); > + } > + } > +} I still think this is a weird place to do this.. :-) See them patches I just send. > +void perf_event_bpf_event(struct bpf_prog *prog, > + enum perf_bpf_event_type type, > + u16 flags) > +{ > + struct perf_bpf_event bpf_event; > + > + if (type <= PERF_BPF_EVENT_UNKNOWN || > + type >= PERF_BPF_EVENT_MAX) > + return; > + > + switch (type) { > + case PERF_BPF_EVENT_PROG_LOAD: > + case PERF_BPF_EVENT_PROG_UNLOAD: > + if (atomic_read(&nr_ksymbol_events)) > + perf_event_bpf_emit_ksymbols(prog, type); > + break; > + default: > + break; > + } > + > + if (!atomic_read(&nr_bpf_events)) > + return; > + > + bpf_event = (struct perf_bpf_event){ > + .prog = prog, > + .event_id = { > + .header = { > + .type = PERF_RECORD_BPF_EVENT, > + .size = sizeof(bpf_event.event_id), > + }, > + .type = type, > + .flags = flags, > + .id = prog->aux->id, > + }, > + }; BUILD_BUG_ON(BPF_TAG_SIZE % sizeof(u64)); > + memcpy(bpf_event.event_id.tag, prog->tag, BPF_TAG_SIZE); > + perf_iterate_sb(perf_event_bpf_output, &bpf_event, NULL); > +} Anyway, small nits only: Acked-by: Peter Zijlstra (Intel)