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[2620:137:e000::1:20]) by mx.google.com with ESMTP id f1-20020a63f741000000b00439ae52c996si10637288pgk.71.2022.11.14.17.06.08; Mon, 14 Nov 2022 17:06:22 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@linux.microsoft.com header.s=default header.b=FSPkqdu4; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linux.microsoft.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237679AbiKOA7k (ORCPT + 99 others); Mon, 14 Nov 2022 19:59:40 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50732 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237684AbiKOA7M (ORCPT ); Mon, 14 Nov 2022 19:59:12 -0500 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 973D217077; Mon, 14 Nov 2022 16:59:10 -0800 (PST) Received: from W11-BEAU-MD.localdomain (unknown [76.135.50.127]) by linux.microsoft.com (Postfix) with ESMTPSA id 5588E20B83E5; Mon, 14 Nov 2022 16:59:09 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 5588E20B83E5 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1668473949; bh=dmkEXknb1A0Qhw2AWPTXryudmpuAFo4IqxhDoe6dNiw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FSPkqdu4n0Z5drfJIWzir3GoLFEkiPdT/7kZx5m/sC/HYHCcvht13A5z9ZvL9Hi+3 gWxCTLx81RBSqdq1UXl6JEpz7tKcBstuXvTikfbzgHhokMboFLTxbWSl+bWX8Q1i1W 1eQoXqqXh71W2Qr9jSg9Ltpp0P3ksW6sPtnH8ZEQ= From: Beau Belgrave To: rostedt@goodmis.org, mhiramat@kernel.org, mathieu.desnoyers@efficios.com, dcook@linux.microsoft.com, alanau@linux.microsoft.com Cc: linux-trace-devel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [RFC PATCH v2 7/7] tracing/user_events: Use write ABI in example Date: Mon, 14 Nov 2022 16:59:02 -0800 Message-Id: <20221115005902.30458-8-beaub@linux.microsoft.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221115005902.30458-1-beaub@linux.microsoft.com> References: <20221115005902.30458-1-beaub@linux.microsoft.com> MIME-Version: 1.0 X-Spam-Status: No, score=-19.8 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,ENV_AND_HDR_SPF_MATCH,RCVD_IN_DNSWL_MED, SPF_HELO_PASS,SPF_PASS,USER_IN_DEF_DKIM_WL,USER_IN_DEF_SPF_WL autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1749522194301997466?= X-GMAIL-MSGID: =?utf-8?q?1749522194301997466?= The ABI has changed to use a remote write approach. Update the example to show the expected use of this new ABI. Also remove debugfs path and use tracefs to ensure example works in more environments. Signed-off-by: Beau Belgrave --- samples/user_events/example.c | 47 +++++++---------------------------- 1 file changed, 9 insertions(+), 38 deletions(-) diff --git a/samples/user_events/example.c b/samples/user_events/example.c index d06dc24156ec..28165a096697 100644 --- a/samples/user_events/example.c +++ b/samples/user_events/example.c @@ -9,51 +9,28 @@ #include #include #include +#include #include #include #include -#include -#include #include -#if __BITS_PER_LONG == 64 -#define endian_swap(x) htole64(x) -#else -#define endian_swap(x) htole32(x) -#endif +const char *data_file = "/sys/kernel/tracing/user_events_data"; +int enabled = 0; -/* Assumes debugfs is mounted */ -const char *data_file = "/sys/kernel/debug/tracing/user_events_data"; -const char *status_file = "/sys/kernel/debug/tracing/user_events_status"; - -static int event_status(long **status) -{ - int fd = open(status_file, O_RDONLY); - - *status = mmap(NULL, sysconf(_SC_PAGESIZE), PROT_READ, - MAP_SHARED, fd, 0); - - close(fd); - - if (*status == MAP_FAILED) - return -1; - - return 0; -} - -static int event_reg(int fd, const char *command, long *index, long *mask, - int *write) +static int event_reg(int fd, const char *command, int *write, int *enabled) { struct user_reg reg = {0}; reg.size = sizeof(reg); + reg.enable_bit = 31; + reg.enable_size = sizeof(*enabled); + reg.enable_addr = (__u64)enabled; reg.name_args = (__u64)command; if (ioctl(fd, DIAG_IOCSREG, ®) == -1) return -1; - *index = reg.status_bit / __BITS_PER_LONG; - *mask = endian_swap(1L << (reg.status_bit % __BITS_PER_LONG)); *write = reg.write_index; return 0; @@ -62,17 +39,12 @@ static int event_reg(int fd, const char *command, long *index, long *mask, int main(int argc, char **argv) { int data_fd, write; - long index, mask; - long *status_page; struct iovec io[2]; __u32 count = 0; - if (event_status(&status_page) == -1) - return errno; - data_fd = open(data_file, O_RDWR); - if (event_reg(data_fd, "test u32 count", &index, &mask, &write) == -1) + if (event_reg(data_fd, "test u32 count", &write, &enabled) == -1) return errno; /* Setup iovec */ @@ -80,13 +52,12 @@ int main(int argc, char **argv) io[0].iov_len = sizeof(write); io[1].iov_base = &count; io[1].iov_len = sizeof(count); - ask: printf("Press enter to check status...\n"); getchar(); /* Check if anyone is listening */ - if (status_page[index] & mask) { + if (enabled) { /* Yep, trace out our data */ writev(data_fd, (const struct iovec *)io, 2);