From patchwork Fri Apr 16 16:46:53 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefano De Venuto X-Patchwork-Id: 12208225 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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 709E3C433B4 for ; Fri, 16 Apr 2021 16:47:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 53FC8610CC for ; Fri, 16 Apr 2021 16:47:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235437AbhDPQrs (ORCPT ); Fri, 16 Apr 2021 12:47:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46778 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234774AbhDPQrs (ORCPT ); Fri, 16 Apr 2021 12:47:48 -0400 Received: from mail-ed1-x52a.google.com (mail-ed1-x52a.google.com [IPv6:2a00:1450:4864:20::52a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 05DEFC061574 for ; Fri, 16 Apr 2021 09:47:23 -0700 (PDT) Received: by mail-ed1-x52a.google.com with SMTP id s15so33067015edd.4 for ; Fri, 16 Apr 2021 09:47:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=4kEuLPZgTDUwopO4CgfnZ2tbOMsYbagQ5qdO4lsnboo=; b=Hwz+5X20AD6WaaQ2j5XJEkaU/0aQQL2gGIZmn8yzV3HqU3zV41hb9dnmLdNUrn0et3 RgIjM5FQDAV7rtfX5YJROvqUr/ik7pRvSPukp+1N2e4dQhPh+kdWPc8AJDGYXJOa+ErW 4Wwe2eFotk5ZKh/QQhKuFZm//xEH/b1ispDyKP9MnSxEbpy530FNBVHPUid2uJGmw/VQ QyHtkqRiFbPRQoaVcSo/J4wyC2ko706aw+68jNVYr21yxbQNydnVqWAmJ+xNz3W7NPGg Ad7aYkR3b3Qf9vjsFLAYw6zGJcwtgjJdoct7LezHy6xItt0s0dFb3hBdsZ+cLIa6Rd/n Sn2w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=4kEuLPZgTDUwopO4CgfnZ2tbOMsYbagQ5qdO4lsnboo=; b=IvZrIVzfEEpkLoXXmf8h0mwoVNC6gu324q4kvbo7MxY7cUL1hyi5/71GZi1ulkvWwL xGlJQP4rZ2aYuDWgN/o+XMVTAaua0wwRag2li3UkxHO8TtnlHPJnY1rEsbsP+YZvyLx4 3rYSjvLkTrCkD2+fVS2RgEXVOQ5QDuvI4m0NkcHbcMO313Vg1RfKPeilYuPYV0gn0Nme 90vxEHSZBUmAdFMl9oYTgaplE/bqQ7efAs34hqjwZu/NxIqEUAyQoF7XZTR9JDXs1WNs WvneZ2oJMoxtvJSiVQXfMchoYu9JZqJA8gBXADIWOQVNjK7YQlKjBm7Mh4VgqXYdL/OD R2qQ== X-Gm-Message-State: AOAM530RTWM4c/ySTOcJpiE67DDvwquRP/ywNIHAeccD/Mv1KAgYwjV8 qsedRJex/1xeCfHd+EQysgw= X-Google-Smtp-Source: ABdhPJyKi9oqeDkhGQvWTO2Uve6HYQX4qmK8dL7/cDIPlauoaG9t0ZPIeEL0L2+9bdCOX/FvaG0hzg== X-Received: by 2002:aa7:d9d7:: with SMTP id v23mr11219778eds.281.1618591641808; Fri, 16 Apr 2021 09:47:21 -0700 (PDT) Received: from DESKTOP-140QBK5.Home ([151.32.127.129]) by smtp.gmail.com with ESMTPSA id m14sm2110830edc.18.2021.04.16.09.47.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 16 Apr 2021 09:47:21 -0700 (PDT) From: Stefano De Venuto To: rostedt@goodmis.org Cc: linux-trace-devel@vger.kernel.org, dfaggioli@suse.com, Stefano De Venuto Subject: [RFC] Simple tool for VMEnters/VMExits matching and trace validation Date: Fri, 16 Apr 2021 18:46:53 +0200 Message-Id: <20210416164653.2949-1-stefano.devenuto99@gmail.com> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-trace-devel@vger.kernel.org Add a tool in examples/ that scans a merged host + guest trace and search for host events that are inside a vmentry/vmexit block (and vice-versa for guest events ouside the block) and report the found ones. It can be useful as a starting point for identifying issues of for checking the effectiveness of host/guest traces synchronization, or even for improving the placing of the tracepoints in the kernel. Signed-off-by: Stefano De Venuto --- examples/checker.c | 202 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 202 insertions(+) create mode 100644 examples/checker.c diff --git a/examples/checker.c b/examples/checker.c new file mode 100644 index 0000000..0b04343 --- /dev/null +++ b/examples/checker.c @@ -0,0 +1,202 @@ +#include +#include +#include + +#include "libkshark.h" +#include "libkshark-tepdata.h" + +#define KVM_ENTRY "kvm/kvm_entry" +#define KVM_EXIT "kvm/kvm_exit" + +struct custom_stream +{ + struct kshark_data_stream* original_stream; + int* cpus; +}; + +int is_guest(int stream_id, + struct kshark_host_guest_map* mapping, + int n_mapping, int* host) +{ + for (int i = 0; i < n_mapping; i++) { + if (mapping[i].guest_id == stream_id) { + *host = mapping[i].host_id; + return 1; + } + } + + return 0; +} + +void print_entry(struct kshark_entry* entry) +{ + struct kshark_data_stream* stream; + char* event_name; + int stream_id; + + stream = kshark_get_stream_from_entry(entry); + event_name = kshark_get_event_name(entry); + + stream_id = stream->stream_id; + printf("%d: %s-%d, %lld [%03d]:%s\t%s\n", + stream->stream_id, + kshark_get_task(entry), + kshark_get_pid(entry), + entry->ts, + entry->cpu, + event_name, + kshark_get_info(entry)); + +} + +void print_entries(struct kshark_entry **entries, ssize_t n_entries) +{ + for (int i = 0; i < n_entries; ++i + print_entry(entries[i]); +} + +void free_data(struct kshark_context *kshark_ctx, + struct custom_stream** custom_streams, + struct kshark_entry** entries, int n_entries, + struct kshark_host_guest_map* host_guest_mapping, + int n_guest) +{ + struct custom_stream* custom_stream; + + for (int i = 0; i < kshark_ctx->n_streams; i++) { + custom_stream = custom_streams[i]; + + free(custom_stream->cpus); + free(custom_stream); + } + free(custom_streams); + + for (int i = 0; i < n_entries; i++) + free(entries[i]); + free(entries); + + kshark_tracecmd_free_hostguest_map(host_guest_mapping, n_guest); + + kshark_close_all(kshark_ctx); + kshark_free(kshark_ctx); +} + +int main(int argc, char **argv) +{ + + struct kshark_host_guest_map* host_guest_mapping; + struct custom_stream** custom_streams; + struct custom_stream* custom_stream; + struct custom_stream* host_stream; + struct kshark_data_stream* stream; + struct kshark_context* kshark_ctx; + struct kshark_entry** entries; + struct kshark_entry* current; + ssize_t n_entries; + char* event_name; + char* token; + int n_guest; + char* info; + int host; + int v_i; + int sd; + + kshark_ctx = NULL; + if (!kshark_instance(&kshark_ctx)) + return 1; + + custom_streams = malloc(sizeof(*custom_streams) * (argc-1)); + + for (int i = 1; i < argc; i++) { + sd = kshark_open(kshark_ctx, argv[i]); + if (sd < 0) { + kshark_free(kshark_ctx); + return 1; + } + + kshark_tep_init_all_buffers(kshark_ctx, sd); + + custom_stream = malloc(sizeof(*custom_stream)); + custom_stream->original_stream = kshark_get_data_stream(kshark_ctx, sd); + custom_stream->cpus = malloc(custom_stream->original_stream->n_cpus * sizeof(int)); + memset(custom_stream->cpus, -1, custom_stream->original_stream->n_cpus * sizeof(int)); + + custom_streams[i-1] = custom_stream; + } + + host_guest_mapping = NULL; + n_guest = kshark_tracecmd_get_hostguest_mapping(&host_guest_mapping); + if (n_guest < 0) { + printf("Failed mapping: %d\n", n_guest); + return 1; + } + + entries = NULL; + n_entries = kshark_load_all_entries(kshark_ctx, &entries); + + for (int i = 0; i < n_entries; ++i) { + current = entries[i]; + + stream = kshark_get_stream_from_entry(current); + event_name = kshark_get_event_name(current); + + custom_stream = custom_streams[stream->stream_id]; + + if (!strcmp(event_name, KVM_ENTRY) || !strcmp(event_name, KVM_EXIT)) { + if (!strcmp(event_name, KVM_ENTRY)) { + + /* + * The recovering process of the vCPU field of the kvm_entry event + * is done by splitting the info field. + */ + info = kshark_get_info(current); + + token = strtok(info, " "); + token = strtok(NULL, " "); + + /* Removing the last comma */ + token[strlen(token) - 1] = '\0'; + + custom_stream->cpus[current->cpu] = atoi(token); + + free(info); + } else { + custom_stream->cpus[current->cpu] = -1; + } + + } else { + + /* + * If the event comes from a guest, recover the pCPU where the event was executed + * and check if it's NOT OUTSIDE a kvm_entry/kvm_exit block. + */ + if (is_guest(stream->stream_id, host_guest_mapping, n_guest, &host)) { + host_stream = custom_streams[host]; + + for (v_i = 0; v_i < host_stream->original_stream->n_cpus; v_i++) { + if (current->cpu == host_stream->cpus[v_i]) + break; + } + + if (v_i == host_stream->original_stream->n_cpus) { + printf("%d G out:\t", i); + print_entry(entries[i]); + } + + /* + * If the event comes from a host, recover the CPU that executed the event + * and check if it's NOT INSIDE a kvm_entry/kvm_exit block. + */ + } else { + if (custom_stream->cpus[current->cpu] != -1) { + printf("%d H in:\t", i); + print_entry(entries[i]); + } + } + } + } + + free_data(kshark_ctx, custom_streams, entries, n_entries, host_guest_mapping, n_guest); +} -- 2.30.2