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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 7EEDFC2D0F8 for ; Wed, 13 May 2020 08:00:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5B65923126 for ; Wed, 13 May 2020 08:00:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729765AbgEMIAI (ORCPT ); Wed, 13 May 2020 04:00:08 -0400 Received: from mga18.intel.com ([134.134.136.126]:47461 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728101AbgEMIAH (ORCPT ); Wed, 13 May 2020 04:00:07 -0400 IronPort-SDR: 4TJe/zd0A1jlrScUiMCC/dcaMK6gz7peDRkGnOZmZrHaw/cDmwGZ+AEoabyjXSFnW/rlpywNXw L9Qk7TywAPxw== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 May 2020 01:00:07 -0700 IronPort-SDR: 8RXeo4PxMRpiUHAQ7B+czY8GOWqKNy88UzY2T2dg56WWddlh9TrRTuyJjAdDIyp8UBgPezvi+D AMVK/d2sxydQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.73,387,1583222400"; d="scan'208";a="371827276" Received: from linux.intel.com ([10.54.29.200]) by fmsmga001.fm.intel.com with ESMTP; 13 May 2020 01:00:06 -0700 Received: from [10.249.229.18] (abudanko-mobl.ccr.corp.intel.com [10.249.229.18]) by linux.intel.com (Postfix) with ESMTP id 0E1BD580646; Wed, 13 May 2020 01:00:03 -0700 (PDT) Subject: [PATCH v3 2/9] perf evlist: implement control command handling functions From: Alexey Budankov To: Arnaldo Carvalho de Melo Cc: Jiri Olsa , Namhyung Kim , Alexander Shishkin , Peter Zijlstra , Ingo Molnar , Andi Kleen , linux-kernel References: Organization: Intel Corp. Message-ID: Date: Wed, 13 May 2020 11:00:02 +0300 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Implement functions of initialization, finalization and processing of control commands coming from control file descriptors. Signed-off-by: Alexey Budankov --- tools/perf/util/evlist.c | 128 +++++++++++++++++++++++++++++++++++++++ tools/perf/util/evlist.h | 17 ++++++ 2 files changed, 145 insertions(+) diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c index aa61619fa304..ea14794e7389 100644 --- a/tools/perf/util/evlist.c +++ b/tools/perf/util/evlist.c @@ -1707,3 +1707,131 @@ struct evsel *perf_evlist__reset_weak_group(struct evlist *evsel_list, } return leader; } + +int evlist__initialize_ctlfd(struct evlist *evlist, int ctl_fd, int ctl_fd_ack) +{ + if (ctl_fd == -1) { + pr_debug("Control descriptor is not initialized\n"); + return 0; + } + + evlist->ctl_fd_pos = perf_evlist__add_pollfd(&evlist->core, ctl_fd, NULL, POLLIN); + if (evlist->ctl_fd_pos < 0) { + evlist->ctl_fd_pos = -1; + pr_err("Failed to add ctl fd entry: %m\n"); + return -1; + } + + evlist->ctl_fd = ctl_fd; + evlist->ctl_fd_ack = ctl_fd_ack; + + return 0; +} + +int evlist__finalize_ctlfd(struct evlist *evlist) +{ + if (evlist->ctl_fd_pos == -1) + return 0; + + evlist->core.pollfd.entries[evlist->ctl_fd_pos].fd = -1; + evlist->ctl_fd_pos = -1; + evlist->ctl_fd_ack = -1; + evlist->ctl_fd = -1; + + return 0; +} + +static int evlist__ctlfd_recv(struct evlist *evlist, enum evlist_ctl_cmd *cmd, + char *cmd_data, size_t data_size) +{ + int err; + char c; + size_t bytes_read = 0; + + memset(cmd_data, 0, data_size--); + + do { + err = read(evlist->ctl_fd, &c, 1); + if (err > 0) { + if (c == '\n' || c == '\0') + break; + cmd_data[bytes_read++] = c; + if (bytes_read == data_size) + break; + } else { + if (err == -1) + pr_err("Failed to read from ctlfd %d: %m\n", evlist->ctl_fd); + break; + } + } while (1); + + pr_debug("Message from ctl_fd: \"%s%s\"\n", cmd_data, + bytes_read == data_size ? "" : c == '\n' ? "\\n" : "\\0"); + + if (err > 0) { + if (!strncmp(cmd_data, EVLIST_CTL_CMD_ENABLE_TAG, + strlen(EVLIST_CTL_CMD_ENABLE_TAG))) { + *cmd = EVLIST_CTL_CMD_ENABLE; + } else if (!strncmp(cmd_data, EVLIST_CTL_CMD_DISABLE_TAG, + strlen(EVLIST_CTL_CMD_DISABLE_TAG))) { + *cmd = EVLIST_CTL_CMD_DISABLE; + } + } + + return err; +} + +static int evlist__ctlfd_ack(struct evlist *evlist) +{ + int err; + + if (evlist->ctl_fd_ack == -1) + return 0; + + err = write(evlist->ctl_fd_ack, EVLIST_CTL_CMD_ACK_TAG, + sizeof(EVLIST_CTL_CMD_ACK_TAG)); + if (err == -1) + pr_err("failed to write to ctl_ack_fd %d: %m\n", evlist->ctl_fd_ack); + + return err; +} + +int evlist__ctlfd_process(struct evlist *evlist, enum evlist_ctl_cmd *cmd) +{ + int err = 0; + char cmd_data[EVLIST_CTL_CMD_MAX_LEN]; + int ctlfd_pos = evlist->ctl_fd_pos; + struct pollfd *entries = evlist->core.pollfd.entries; + + if (!entries[ctlfd_pos].revents) + return 0; + + if (entries[ctlfd_pos].revents & POLLIN) { + err = evlist__ctlfd_recv(evlist, cmd, cmd_data, + EVLIST_CTL_CMD_MAX_LEN); + if (err > 0) { + switch (*cmd) { + case EVLIST_CTL_CMD_ENABLE: + evlist__enable(evlist); + break; + case EVLIST_CTL_CMD_DISABLE: + evlist__disable(evlist); + break; + case EVLIST_CTL_CMD_ACK: + case EVLIST_CTL_CMD_UNSUPPORTED: + default: + pr_debug("ctlfd: unsupported %d\n", *cmd); + break; + } + if (!(*cmd == EVLIST_CTL_CMD_ACK || *cmd == EVLIST_CTL_CMD_UNSUPPORTED)) + evlist__ctlfd_ack(evlist); + } + } + + if (entries[ctlfd_pos].revents & (POLLHUP | POLLERR)) + evlist__finalize_ctlfd(evlist); + else + entries[ctlfd_pos].revents = 0; + + return err; +} diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h index 62f259d89b41..0554f8d2a65b 100644 --- a/tools/perf/util/evlist.h +++ b/tools/perf/util/evlist.h @@ -358,4 +358,21 @@ void perf_evlist__force_leader(struct evlist *evlist); struct evsel *perf_evlist__reset_weak_group(struct evlist *evlist, struct evsel *evsel, bool close); +#define EVLIST_CTL_CMD_ENABLE_TAG "enable" +#define EVLIST_CTL_CMD_DISABLE_TAG "disable" +#define EVLIST_CTL_CMD_ACK_TAG "ack\n" + +#define EVLIST_CTL_CMD_MAX_LEN 64 + +enum evlist_ctl_cmd { + EVLIST_CTL_CMD_UNSUPPORTED = 0, + EVLIST_CTL_CMD_ENABLE, + EVLIST_CTL_CMD_DISABLE, + EVLIST_CTL_CMD_ACK +}; + +int evlist__initialize_ctlfd(struct evlist *evlist, int ctl_fd, int ctl_fd_ack); +int evlist__finalize_ctlfd(struct evlist *evlist); +int evlist__ctlfd_process(struct evlist *evlist, enum evlist_ctl_cmd *cmd); + #endif /* __PERF_EVLIST_H */ -- 2.24.1