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 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: *
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 tests in the bpf selftest code still refer to this older debugfs path, so let's update them to avoid confusion.
Signed-off-by: Ross Zwisler zwisler@google.com Acked-by: Michael S. Tsirkin mst@redhat.com ---
[ Per Alexei's request, resending towards bpf-next ]
tools/testing/selftests/bpf/get_cgroup_id_user.c | 2 +- .../testing/selftests/bpf/prog_tests/kprobe_multi_test.c | 2 +- tools/testing/selftests/bpf/prog_tests/task_fd_query_tp.c | 2 +- tools/testing/selftests/bpf/prog_tests/tp_attach_query.c | 2 +- tools/testing/selftests/bpf/prog_tests/trace_printk.c | 2 +- tools/testing/selftests/bpf/prog_tests/trace_vprintk.c | 2 +- tools/testing/selftests/bpf/progs/test_stacktrace_map.c | 2 +- tools/testing/selftests/bpf/progs/test_tracepoint.c | 2 +- tools/testing/selftests/bpf/test_ftrace.sh | 2 +- tools/testing/selftests/bpf/test_tunnel.sh | 8 ++++---- tools/testing/selftests/bpf/trace_helpers.c | 4 ++-- 11 files changed, 15 insertions(+), 15 deletions(-)
diff --git a/tools/testing/selftests/bpf/get_cgroup_id_user.c b/tools/testing/selftests/bpf/get_cgroup_id_user.c index 156743cf5870..478e080128be 100644 --- a/tools/testing/selftests/bpf/get_cgroup_id_user.c +++ b/tools/testing/selftests/bpf/get_cgroup_id_user.c @@ -87,7 +87,7 @@ int main(int argc, char **argv) bpf_map_update_elem(pidmap_fd, &key, &pid, 0);
snprintf(buf, sizeof(buf), - "/sys/kernel/debug/tracing/events/%s/id", probe_name); + "/sys/kernel/tracing/events/%s/id", probe_name); efd = open(buf, O_RDONLY, 0); if (CHECK(efd < 0, "open", "err %d errno %d\n", efd, errno)) goto close_prog; diff --git a/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c b/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c index c6f37e825f11..6f0f2d8984db 100644 --- a/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c +++ b/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c @@ -338,7 +338,7 @@ static int get_syms(char ***symsp, size_t *cntp) * Filtering out duplicates by using hashmap__add, which won't * add existing entry. */ - f = fopen("/sys/kernel/debug/tracing/available_filter_functions", "r"); + f = fopen("/sys/kernel/tracing/available_filter_functions", "r"); if (!f) return -EINVAL;
diff --git a/tools/testing/selftests/bpf/prog_tests/task_fd_query_tp.c b/tools/testing/selftests/bpf/prog_tests/task_fd_query_tp.c index c717741bf8b6..6d70559fc19b 100644 --- a/tools/testing/selftests/bpf/prog_tests/task_fd_query_tp.c +++ b/tools/testing/selftests/bpf/prog_tests/task_fd_query_tp.c @@ -18,7 +18,7 @@ static void test_task_fd_query_tp_core(const char *probe_name, goto close_prog;
snprintf(buf, sizeof(buf), - "/sys/kernel/debug/tracing/events/%s/id", probe_name); + "/sys/kernel/tracing/events/%s/id", probe_name); efd = open(buf, O_RDONLY, 0); if (CHECK(efd < 0, "open", "err %d errno %d\n", efd, errno)) goto close_prog; diff --git a/tools/testing/selftests/bpf/prog_tests/tp_attach_query.c b/tools/testing/selftests/bpf/prog_tests/tp_attach_query.c index a479080533db..4308e3a828d8 100644 --- a/tools/testing/selftests/bpf/prog_tests/tp_attach_query.c +++ b/tools/testing/selftests/bpf/prog_tests/tp_attach_query.c @@ -17,7 +17,7 @@ void serial_test_tp_attach_query(void) obj[i] = NULL;
snprintf(buf, sizeof(buf), - "/sys/kernel/debug/tracing/events/sched/sched_switch/id"); + "/sys/kernel/tracing/events/sched/sched_switch/id"); efd = open(buf, O_RDONLY, 0); if (CHECK(efd < 0, "open", "err %d errno %d\n", efd, errno)) return; diff --git a/tools/testing/selftests/bpf/prog_tests/trace_printk.c b/tools/testing/selftests/bpf/prog_tests/trace_printk.c index cade7f12315f..ff50a928cb98 100644 --- a/tools/testing/selftests/bpf/prog_tests/trace_printk.c +++ b/tools/testing/selftests/bpf/prog_tests/trace_printk.c @@ -5,7 +5,7 @@
#include "trace_printk.lskel.h"
-#define TRACEBUF "/sys/kernel/debug/tracing/trace_pipe" +#define TRACEBUF "/sys/kernel/tracing/trace_pipe" #define SEARCHMSG "testing,testing"
void serial_test_trace_printk(void) diff --git a/tools/testing/selftests/bpf/prog_tests/trace_vprintk.c b/tools/testing/selftests/bpf/prog_tests/trace_vprintk.c index 7a4e313e8558..e568d7f247ec 100644 --- a/tools/testing/selftests/bpf/prog_tests/trace_vprintk.c +++ b/tools/testing/selftests/bpf/prog_tests/trace_vprintk.c @@ -5,7 +5,7 @@
#include "trace_vprintk.lskel.h"
-#define TRACEBUF "/sys/kernel/debug/tracing/trace_pipe" +#define TRACEBUF "/sys/kernel/tracing/trace_pipe" #define SEARCHMSG "1,2,3,4,5,6,7,8,9,10"
void serial_test_trace_vprintk(void) diff --git a/tools/testing/selftests/bpf/progs/test_stacktrace_map.c b/tools/testing/selftests/bpf/progs/test_stacktrace_map.c index 728dbd39eff0..47568007b668 100644 --- a/tools/testing/selftests/bpf/progs/test_stacktrace_map.c +++ b/tools/testing/selftests/bpf/progs/test_stacktrace_map.c @@ -38,7 +38,7 @@ struct { __type(value, stack_trace_t); } stack_amap SEC(".maps");
-/* 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/tools/testing/selftests/bpf/progs/test_tracepoint.c b/tools/testing/selftests/bpf/progs/test_tracepoint.c index 43bd7a20cc50..4cb8bbb6a320 100644 --- a/tools/testing/selftests/bpf/progs/test_tracepoint.c +++ b/tools/testing/selftests/bpf/progs/test_tracepoint.c @@ -4,7 +4,7 @@ #include <vmlinux.h> #include <bpf/bpf_helpers.h>
-/* 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/tools/testing/selftests/bpf/test_ftrace.sh b/tools/testing/selftests/bpf/test_ftrace.sh index 20de7bb873bc..e3e2328a1b65 100755 --- a/tools/testing/selftests/bpf/test_ftrace.sh +++ b/tools/testing/selftests/bpf/test_ftrace.sh @@ -1,6 +1,6 @@ #!/bin/bash
-TR=/sys/kernel/debug/tracing/ +TR=/sys/kernel/tracing/ clear_trace() { # reset trace output echo > $TR/trace } diff --git a/tools/testing/selftests/bpf/test_tunnel.sh b/tools/testing/selftests/bpf/test_tunnel.sh index 2eaedc1d9ed3..bbbd242f7cef 100755 --- a/tools/testing/selftests/bpf/test_tunnel.sh +++ b/tools/testing/selftests/bpf/test_tunnel.sh @@ -543,7 +543,7 @@ setup_xfrm_tunnel() test_xfrm_tunnel() { config_device - > /sys/kernel/debug/tracing/trace + > /sys/kernel/tracing/trace setup_xfrm_tunnel mkdir -p ${BPF_PIN_TUNNEL_DIR} bpftool prog loadall ${BPF_FILE} ${BPF_PIN_TUNNEL_DIR} @@ -552,11 +552,11 @@ test_xfrm_tunnel() ${BPF_PIN_TUNNEL_DIR}/xfrm_get_state ip netns exec at_ns0 ping $PING_ARG 10.1.1.200 sleep 1 - grep "reqid 1" /sys/kernel/debug/tracing/trace + grep "reqid 1" /sys/kernel/tracing/trace check_err $? - grep "spi 0x1" /sys/kernel/debug/tracing/trace + grep "spi 0x1" /sys/kernel/tracing/trace check_err $? - grep "remote ip 0xac100164" /sys/kernel/debug/tracing/trace + grep "remote ip 0xac100164" /sys/kernel/tracing/trace check_err $? cleanup
diff --git a/tools/testing/selftests/bpf/trace_helpers.c b/tools/testing/selftests/bpf/trace_helpers.c index 09a16a77bae4..d2816aa35a9b 100644 --- a/tools/testing/selftests/bpf/trace_helpers.c +++ b/tools/testing/selftests/bpf/trace_helpers.c @@ -12,7 +12,7 @@ #include <sys/mman.h> #include "trace_helpers.h"
-#define DEBUGFS "/sys/kernel/debug/tracing/" +#define TRACEFS "/sys/kernel/tracing/"
#define MAX_SYMS 300000 static struct ksym syms[MAX_SYMS]; @@ -136,7 +136,7 @@ void read_trace_pipe(void) { int trace_fd;
- trace_fd = open(DEBUGFS "trace_pipe", O_RDONLY, 0); + trace_fd = open(TRACEFS "trace_pipe", O_RDONLY, 0); if (trace_fd < 0) return;
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. Itprints 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, ifavailable. It can take up to three additional **u64**arguments (as an eBPF helpers, the total number of arguments islimited 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 outputone 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 usuallydefaults 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
*/ struct ib_umad_rw_args { u64 pad;
- /sys/kernel/tracing/events/ib_umad/ib_umad_write/format
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. Itprints 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, ifavailable. It can take up to three additional **u64**arguments (as an eBPF helpers, the total number of arguments islimited 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 outputone 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 usuallydefaults to something like:-- 2.39.1.581.gbfd45094c4-goog
On Mon, Feb 13, 2023 at 06:57:16PM -0800, Stanislav Fomichev wrote:
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?
Oh, apologies, I was using Linus's master branch as my baseline. I'll send out a v2.
linux-kselftest-mirror@lists.linaro.org
-
Ross Zwisler -
Ross Zwisler -
Stanislav Fomichev