From: Stanislav Fomichev <sdf@google.com>
To: Ross Zwisler <zwisler@chromium.org>
Cc: linux-kernel@vger.kernel.org, Ross Zwisler <zwisler@google.com>,
Alexei Starovoitov <ast@kernel.org>,
Andrii Nakryiko <andrii@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>,
Hao Luo <haoluo@google.com>, Jason Gunthorpe <jgg@ziepe.ca>,
Jiri Olsa <jolsa@kernel.org>,
John Fastabend <john.fastabend@gmail.com>,
KP Singh <kpsingh@kernel.org>, Leon Romanovsky <leon@kernel.org>,
Martin KaFai Lau <martin.lau@linux.dev>,
Mykola Lysenko <mykolal@fb.com>, Shuah Khan <shuah@kernel.org>,
Song Liu <song@kernel.org>, Yonghong Song <yhs@fb.com>,
bpf@vger.kernel.org, linux-kselftest@vger.kernel.org,
linux-rdma@vger.kernel.org, Steven Rostedt <rostedt@goodmis.org>,
linux-trace-kernel@vger.kernel.org,
"Michael S . Tsirkin" <mst@redhat.com>
Subject: Re: [PATCH bpf-next 1/2] bpf: use canonical ftrace path
Date: Mon, 13 Feb 2023 18:57:16 -0800 [thread overview]
Message-ID: <Y+r4jLwWvhcvyuih@google.com> (raw)
In-Reply-To: <20230213221835.592763-1-zwisler@google.com>
On 02/13, Ross Zwisler wrote:
> 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.
Doesn't seem to apply cleanly to bpf-next?
https://github.com/kernel-patches/bpf/pull/4584
> Signed-off-by: Ross Zwisler <zwisler@google.com>
> Acked-by: Michael S. Tsirkin <mst@redhat.com>
> ---
> [ Per Alexei's request, resending towards bpf-next ]
> 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_kern.c | 4 ++--
> tools/include/uapi/linux/bpf.h | 8 ++++----
> 10 files changed, 21 insertions(+), 21 deletions(-)
> diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
> index 464ca3f01fe7..44387b31cbde 100644
> --- a/include/uapi/linux/bpf.h
> +++ b/include/uapi/linux/bpf.h
> @@ -1642,17 +1642,17 @@ 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 0eda9754f50b..11fa0a087db6 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
> -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 65a976058dd3..db5691e6637f 100755
> --- a/samples/bpf/test_lwt_bpf.sh
> +++ b/samples/bpf/test_lwt_bpf.sh
> @@ -19,7 +19,7 @@ IPVETH3="192.168.111.2"
> IP_LOCAL="192.168.99.1"
> -TRACE_ROOT=/sys/kernel/debug/tracing
> +TRACE_ROOT=/sys/kernel/tracing
> function lookup_mac()
> {
> diff --git a/samples/bpf/test_overhead_tp_kern.c
> b/samples/bpf/test_overhead_tp_kern.c
> index 80edadacb692..a1d53b0d8476 100644
> --- a/samples/bpf/test_overhead_tp_kern.c
> +++ b/samples/bpf/test_overhead_tp_kern.c
> @@ -8,7 +8,7 @@
> #include <uapi/linux/bpf.h>
> #include <bpf/bpf_helpers.h>
> -/* 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;
> @@ -22,7 +22,7 @@ int prog(struct task_rename *ctx)
> return 0;
> }
> -/* from /sys/kernel/debug/tracing/events/random/urandom_read/format */
> +/* from /sys/kernel/tracing/events/random/urandom_read/format */
> struct urandom_read {
> __u64 pad;
> int got_bits;
> diff --git a/tools/include/uapi/linux/bpf.h
> b/tools/include/uapi/linux/bpf.h
> index 464ca3f01fe7..44387b31cbde 100644
> --- a/tools/include/uapi/linux/bpf.h
> +++ b/tools/include/uapi/linux/bpf.h
> @@ -1642,17 +1642,17 @@ 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:
> *
> --
> 2.39.1.581.gbfd45094c4-goog
next prev parent reply other threads:[~2023-02-14 2:58 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-02-13 22:18 [PATCH bpf-next 1/2] bpf: use canonical ftrace path Ross Zwisler
2023-02-13 22:18 ` [PATCH bpf-next 2/2] selftests/bpf: " Ross Zwisler
2023-02-14 2:57 ` Stanislav Fomichev [this message]
2023-02-14 16:23 ` [PATCH bpf-next 1/2] bpf: " Ross Zwisler
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=Y+r4jLwWvhcvyuih@google.com \
--to=sdf@google.com \
--cc=andrii@kernel.org \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=haoluo@google.com \
--cc=jgg@ziepe.ca \
--cc=john.fastabend@gmail.com \
--cc=jolsa@kernel.org \
--cc=kpsingh@kernel.org \
--cc=leon@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-kselftest@vger.kernel.org \
--cc=linux-rdma@vger.kernel.org \
--cc=linux-trace-kernel@vger.kernel.org \
--cc=martin.lau@linux.dev \
--cc=mst@redhat.com \
--cc=mykolal@fb.com \
--cc=rostedt@goodmis.org \
--cc=shuah@kernel.org \
--cc=song@kernel.org \
--cc=yhs@fb.com \
--cc=zwisler@chromium.org \
--cc=zwisler@google.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).