From patchwork Fri Mar 10 17:52:08 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ross Zwisler X-Patchwork-Id: 13169885 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8C1CBC76186 for ; Fri, 10 Mar 2023 17:52:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231548AbjCJRwZ (ORCPT ); Fri, 10 Mar 2023 12:52:25 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52214 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230350AbjCJRwY (ORCPT ); Fri, 10 Mar 2023 12:52:24 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 17FB676161; Fri, 10 Mar 2023 09:52:21 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id CAB94B82089; Fri, 10 Mar 2023 17:52:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C410EC433D2; Fri, 10 Mar 2023 17:52:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1678470738; bh=O+Esizz49eDVD0nZLwhoBoCxIFUOp9NOk9OqSnjPQP8=; h=From:To:Cc:Subject:Date:From; b=UkUlkxNlx5RfT2h9XJDJ+K6Ghs/ACyaUvyGJ4UfA8INn1gENYxXy8OgWanrAkr4xX XKI9IxAW8Un40yLb64V50xs1JAChu+0cT55iUaSCK2ucCoMlS65wKwaZKZJdJJ0GA1 UmXCu1gx6dwF3LcDmuGjW5nlGgMmKHEvxuPMdmCqlfXEP8Td4033zQDkvCQ6EjFyNW CrOjtQdEEKTvJurefcUiExoE6WR0xXAYe65LHR+NLo9sau+YRzFpzxyfJLOLF3zLYP WbRLnY5G1A9Rh2w7jyMthUWa14xocBLUfuGYkBTPC+8QJ843LpPVSUZcKuBLpcT18L Yy3Ctl+ne6zFA== From: zwisler@kernel.org To: bpf@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Ross Zwisler , Alexei Starovoitov , Andrii Nakryiko , Daniel Borkmann , Hao Luo , Jason Gunthorpe , Jiri Olsa , John Fastabend , KP Singh , Leon Romanovsky , Martin KaFai Lau , Mykola Lysenko , Shuah Khan , Song Liu , Stanislav Fomichev , Yonghong Song , linux-kselftest@vger.kernel.org, linux-rdma@vger.kernel.org, linux-trace-kernel@vger.kernel.org, Steven Rostedt , "Michael S . Tsirkin" Subject: [PATCH bpf-next v3 1/2] bpf: use canonical ftrace path Date: Fri, 10 Mar 2023 10:52:08 -0700 Message-Id: <20230310175209.2130880-1-zwisler@kernel.org> X-Mailer: git-send-email 2.40.0.rc1.284.g88254d51c5-goog MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-trace-kernel@vger.kernel.org From: Ross Zwisler The canonical location for the tracefs filesystem is at /sys/kernel/tracing. But, from Documentation/trace/ftrace.rst: Before 4.1, all ftrace tracing control files were within the debugfs file system, which is typically located at /sys/kernel/debug/tracing. For backward compatibility, when mounting the debugfs file system, the tracefs file system will be automatically mounted at: /sys/kernel/debug/tracing Many comments and samples in the bpf code still refer to this older debugfs path, so let's update them to avoid confusion. There are a few spots where the bpf code explicitly checks both tracefs and debugfs (tools/bpf/bpftool/tracelog.c and tools/lib/api/fs/fs.c) and I've left those alone so that the tools can continue to work with both paths. Signed-off-by: Ross Zwisler Acked-by: Michael S. Tsirkin Reviewed-by: Steven Rostedt (Google) --- v2 was submitted to bpf-next via a pair of pull requests: https://github.com/kernel-patches/bpf/pull/4672 https://github.com/kernel-patches/bpf/pull/4648 The only change since v2 is that I rebased on the current bpf-next_base. I've run this through all the BPF selftests on a local machine: sudo ./test_verifier sudo make run_tests and didn't hit any regressions. I've also tested to make sure each modified selftest runs successfully with each path of tracefs (with and without debugfs). --- include/uapi/linux/bpf.h | 8 ++++---- samples/bpf/cpustat_kern.c | 4 ++-- samples/bpf/hbm.c | 4 ++-- samples/bpf/ibumad_kern.c | 4 ++-- samples/bpf/lwt_len_hist.sh | 2 +- samples/bpf/offwaketime_kern.c | 2 +- samples/bpf/task_fd_query_user.c | 4 ++-- samples/bpf/test_lwt_bpf.sh | 2 +- samples/bpf/test_overhead_tp.bpf.c | 4 ++-- tools/include/uapi/linux/bpf.h | 8 ++++---- 10 files changed, 21 insertions(+), 21 deletions(-) base-commit: d1d51a62d060d02f99ee407959e24ad10a40e053 prerequisite-patch-id: 9d1a70f239e7476600fe4018125df58a368dc725 prerequisite-patch-id: 29fea9a24684ec09762b277403d7bffffb25cdf3 prerequisite-patch-id: 9cb5a22a0f88413c393ddc29f264fbd96938c598 prerequisite-patch-id: 87ce0f3257a51e8cc06dd21ae3fa4102406ba4b4 prerequisite-patch-id: a46e67372e8493e5f7dab95f72281bd690cbeacf prerequisite-patch-id: bae92ed6da92da5587f8d54fed5976c7dd6a468a prerequisite-patch-id: c84726372fab0771a2c2ff0942f13a9556db8740 prerequisite-patch-id: 8a1a8806ec58ca208ee81f83557af90472fcba7f prerequisite-patch-id: 0f7d6ec99549b042bc37603a2a9034853015a6d6 prerequisite-patch-id: 88a110f7993c374c6df429a1f67706e5abd65a02 prerequisite-patch-id: 3ada332d91275a471e9b65eb532571ef5caad4af prerequisite-patch-id: e7ade2dda63127886579bf88f3eddda82d6a103b prerequisite-patch-id: a49488cb1b167a9c85405c142cc3edb7bdb32c3d prerequisite-patch-id: 9656ecd9c036e140d819c3929f01ac7264452382 prerequisite-patch-id: d1fa19bc1974a78632f48080b4eef3d4d6c07d3d prerequisite-patch-id: 245b71b3aecf33a9d2a9609fc45f72ac50d1e92a prerequisite-patch-id: 1253300de46fe258927fd3ddd5009a1468f6e69b prerequisite-patch-id: 638e5805bdaa8842589729a26707c47a593464c2 prerequisite-patch-id: 1d08f9dfe4c360d566edbee925424b789e0f844b prerequisite-patch-id: b6c73e77b10fc771566de294973334646cad4d44 prerequisite-patch-id: 57034da9a1b439c9fa3ecca69a099204a339502a prerequisite-patch-id: ef11bfbcdf2239002958554e2dc5fbe8ec4d6e9a prerequisite-patch-id: 68c01f7ca5b9c740b9259b73d97f168765c794d0 prerequisite-patch-id: 846110172a75fdaf1017da1fec3709fa301a5a47 prerequisite-patch-id: 8070c339fe5ce2e46b5de76b59d0a3f2c25d9abb prerequisite-patch-id: c48cc68777605390db454b6392569ccdcd88cdc1 prerequisite-patch-id: 0d36d64d21de2d0df3ac31c5203a5cd868b4be47 prerequisite-patch-id: 6538cefc509c89e2375dcb6dc85d11fb6993474d prerequisite-patch-id: dc57bbf1190a31aec332cab39f990ac568e6722d prerequisite-patch-id: 0d90b60b4ce60024f31f576bab79453f6d480a8e prerequisite-patch-id: 15c1914741be406aeee6c66332f079f3f8367751 prerequisite-patch-id: 78a735554858860fa695dd9e20bf7c5a41fafe20 prerequisite-patch-id: 238aaa7c1f55fdac815a6e14310d074c1ac70983 prerequisite-patch-id: d514061d937de74e8cc3d8848488a60dad2e2a2e prerequisite-patch-id: 0f1a878f5768b886db78ea0fc6fe17d2297daa2e prerequisite-patch-id: fa48be79a1e1e1c611d7975501a8f9dfa6f1c4fe prerequisite-patch-id: 0a193e915faed8479f150c30ba0c335e288f634f prerequisite-patch-id: 2cab00be3bb34454f98dac426301468e7ef12ad1 prerequisite-patch-id: daa2a81b90fda8ca09d11a35aff5a282e6f76ec2 prerequisite-patch-id: 5001694a51d83ed8ca428855b92b3ead261a469d diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index d8c534e05b0a..13129df937cd 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -1647,17 +1647,17 @@ union bpf_attr { * Description * This helper is a "printk()-like" facility for debugging. It * prints a message defined by format *fmt* (of size *fmt_size*) - * to file *\/sys/kernel/debug/tracing/trace* from DebugFS, if + * to file *\/sys/kernel/tracing/trace* from TraceFS, if * available. It can take up to three additional **u64** * arguments (as an eBPF helpers, the total number of arguments is * limited to five). * * Each time the helper is called, it appends a line to the trace. - * Lines are discarded while *\/sys/kernel/debug/tracing/trace* is - * open, use *\/sys/kernel/debug/tracing/trace_pipe* to avoid this. + * Lines are discarded while *\/sys/kernel/tracing/trace* is + * open, use *\/sys/kernel/tracing/trace_pipe* to avoid this. * The format of the trace is customizable, and the exact output * one will get depends on the options set in - * *\/sys/kernel/debug/tracing/trace_options* (see also the + * *\/sys/kernel/tracing/trace_options* (see also the * *README* file under the same directory). However, it usually * defaults to something like: * diff --git a/samples/bpf/cpustat_kern.c b/samples/bpf/cpustat_kern.c index 5aefd19cdfa1..944f13fe164a 100644 --- a/samples/bpf/cpustat_kern.c +++ b/samples/bpf/cpustat_kern.c @@ -76,8 +76,8 @@ struct { /* * The trace events for cpu_idle and cpu_frequency are taken from: - * /sys/kernel/debug/tracing/events/power/cpu_idle/format - * /sys/kernel/debug/tracing/events/power/cpu_frequency/format + * /sys/kernel/tracing/events/power/cpu_idle/format + * /sys/kernel/tracing/events/power/cpu_frequency/format * * These two events have same format, so define one common structure. */ diff --git a/samples/bpf/hbm.c b/samples/bpf/hbm.c index 516fbac28b71..ff58ec43f56a 100644 --- a/samples/bpf/hbm.c +++ b/samples/bpf/hbm.c @@ -65,7 +65,7 @@ static void Usage(void); static void read_trace_pipe2(void); static void do_error(char *msg, bool errno_flag); -#define DEBUGFS "/sys/kernel/debug/tracing/" +#define TRACEFS "/sys/kernel/tracing/" static struct bpf_program *bpf_prog; static struct bpf_object *obj; @@ -77,7 +77,7 @@ static void read_trace_pipe2(void) FILE *outf; char *outFname = "hbm_out.log"; - trace_fd = open(DEBUGFS "trace_pipe", O_RDONLY, 0); + trace_fd = open(TRACEFS "trace_pipe", O_RDONLY, 0); if (trace_fd < 0) { printf("Error opening trace_pipe\n"); return; diff --git a/samples/bpf/ibumad_kern.c b/samples/bpf/ibumad_kern.c index 9b193231024a..f07474c72525 100644 --- a/samples/bpf/ibumad_kern.c +++ b/samples/bpf/ibumad_kern.c @@ -39,8 +39,8 @@ struct { /* Taken from the current format defined in * include/trace/events/ib_umad.h * and - * /sys/kernel/debug/tracing/events/ib_umad/ib_umad_read/format - * /sys/kernel/debug/tracing/events/ib_umad/ib_umad_write/format + * /sys/kernel/tracing/events/ib_umad/ib_umad_read/format + * /sys/kernel/tracing/events/ib_umad/ib_umad_write/format */ struct ib_umad_rw_args { u64 pad; diff --git a/samples/bpf/lwt_len_hist.sh b/samples/bpf/lwt_len_hist.sh index 7078bfcc4f4d..381b2c634784 100755 --- a/samples/bpf/lwt_len_hist.sh +++ b/samples/bpf/lwt_len_hist.sh @@ -5,7 +5,7 @@ NS1=lwt_ns1 VETH0=tst_lwt1a VETH1=tst_lwt1b BPF_PROG=lwt_len_hist.bpf.o -TRACE_ROOT=/sys/kernel/debug/tracing +TRACE_ROOT=/sys/kernel/tracing function cleanup { # To reset saved histogram, remove pinned map diff --git a/samples/bpf/offwaketime_kern.c b/samples/bpf/offwaketime_kern.c index eb4d94742e6b..23f12b47e9e5 100644 --- a/samples/bpf/offwaketime_kern.c +++ b/samples/bpf/offwaketime_kern.c @@ -110,7 +110,7 @@ static inline int update_counts(void *ctx, u32 pid, u64 delta) } #if 1 -/* taken from /sys/kernel/debug/tracing/events/sched/sched_switch/format */ +/* taken from /sys/kernel/tracing/events/sched/sched_switch/format */ struct sched_switch_args { unsigned long long pad; char prev_comm[TASK_COMM_LEN]; diff --git a/samples/bpf/task_fd_query_user.c b/samples/bpf/task_fd_query_user.c index a33d74bd3a4b..1e61f2180470 100644 --- a/samples/bpf/task_fd_query_user.c +++ b/samples/bpf/task_fd_query_user.c @@ -235,7 +235,7 @@ static int test_debug_fs_uprobe(char *binary_path, long offset, bool is_return) struct bpf_link *link; ssize_t bytes; - snprintf(buf, sizeof(buf), "/sys/kernel/debug/tracing/%s_events", + snprintf(buf, sizeof(buf), "/sys/kernel/tracing/%s_events", event_type); kfd = open(buf, O_WRONLY | O_TRUNC, 0); CHECK_PERROR_RET(kfd < 0); @@ -252,7 +252,7 @@ static int test_debug_fs_uprobe(char *binary_path, long offset, bool is_return) close(kfd); kfd = -1; - snprintf(buf, sizeof(buf), "/sys/kernel/debug/tracing/events/%ss/%s/id", + snprintf(buf, sizeof(buf), "/sys/kernel/tracing/events/%ss/%s/id", event_type, event_alias); efd = open(buf, O_RDONLY, 0); CHECK_PERROR_RET(efd < 0); diff --git a/samples/bpf/test_lwt_bpf.sh b/samples/bpf/test_lwt_bpf.sh index 2e9f5126963b..0bf2d0f6bf4b 100755 --- a/samples/bpf/test_lwt_bpf.sh +++ b/samples/bpf/test_lwt_bpf.sh @@ -21,7 +21,7 @@ IP_LOCAL="192.168.99.1" PROG_SRC="test_lwt_bpf.c" BPF_PROG="test_lwt_bpf.o" -TRACE_ROOT=/sys/kernel/debug/tracing +TRACE_ROOT=/sys/kernel/tracing CONTEXT_INFO=$(cat ${TRACE_ROOT}/trace_options | grep context) function lookup_mac() diff --git a/samples/bpf/test_overhead_tp.bpf.c b/samples/bpf/test_overhead_tp.bpf.c index 67cab3881969..8b498328e961 100644 --- a/samples/bpf/test_overhead_tp.bpf.c +++ b/samples/bpf/test_overhead_tp.bpf.c @@ -7,7 +7,7 @@ #include "vmlinux.h" #include -/* from /sys/kernel/debug/tracing/events/task/task_rename/format */ +/* from /sys/kernel/tracing/events/task/task_rename/format */ struct task_rename { __u64 pad; __u32 pid; @@ -21,7 +21,7 @@ int prog(struct task_rename *ctx) return 0; } -/* from /sys/kernel/debug/tracing/events/fib/fib_table_lookup/format */ +/* from /sys/kernel/tracing/events/fib/fib_table_lookup/format */ struct fib_table_lookup { __u64 pad; __u32 tb_id; diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index d8c534e05b0a..13129df937cd 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -1647,17 +1647,17 @@ union bpf_attr { * Description * This helper is a "printk()-like" facility for debugging. It * prints a message defined by format *fmt* (of size *fmt_size*) - * to file *\/sys/kernel/debug/tracing/trace* from DebugFS, if + * to file *\/sys/kernel/tracing/trace* from TraceFS, if * available. It can take up to three additional **u64** * arguments (as an eBPF helpers, the total number of arguments is * limited to five). * * Each time the helper is called, it appends a line to the trace. - * Lines are discarded while *\/sys/kernel/debug/tracing/trace* is - * open, use *\/sys/kernel/debug/tracing/trace_pipe* to avoid this. + * Lines are discarded while *\/sys/kernel/tracing/trace* is + * open, use *\/sys/kernel/tracing/trace_pipe* to avoid this. * The format of the trace is customizable, and the exact output * one will get depends on the options set in - * *\/sys/kernel/debug/tracing/trace_options* (see also the + * *\/sys/kernel/tracing/trace_options* (see also the * *README* file under the same directory). However, it usually * defaults to something like: *