kernel/linux.git/samples/bpf/offwaketime_kern.c, branch linux-6.5.y

bpf: use canonical ftrace path

2023-03-14T04:51:30+00:00

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) Link: https://lore.kernel.org/r/20230313205628.1058720-2-zwisler@kernel.org Signed-off-by: Alexei Starovoitov

samples/bpf/test_overhead_kprobe_kern: replace bpf_probe_read_kernel with bpf_probe_read_kernel_str to get task comm

2022-01-20T06:52:53+00:00

bpf_probe_read_kernel_str() will add a nul terminator to the dst, then we don't care about if the dst size is big enough. This patch also replaces the hard-coded 16 with TASK_COMM_LEN to make it grepable. Link: https://lkml.kernel.org/r/20211120112738.45980-6-laoar.shao@gmail.com Signed-off-by: Yafang Shao Reviewed-by: Kees Cook Acked-by: Andrii Nakryiko Reviewed-by: David Hildenbrand Cc: Mathieu Desnoyers Cc: Arnaldo Carvalho de Melo Cc: Alexei Starovoitov Cc: Andrii Nakryiko Cc: Michal Miroslaw Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Matthew Wilcox Cc: David Hildenbrand Cc: Al Viro Cc: Kees Cook Cc: Petr Mladek Cc: Dennis Dalessandro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

samples/bpf: Define MAX_ENTRIES instead of a magic number in offwaketime

2021-08-15T07:08:40+00:00

Define MAX_ENTRIES instead of using 10000 as a magic number in various places. Signed-off-by: Muhammad Falak R Wani Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20210815065013.15411-1-falakreyaz@gmail.com

samples: bpf: Refactor tracepoint tracing programs with libbpf

2020-08-25T03:59:35+00:00

For the problem of increasing fragmentation of the bpf loader programs, instead of using bpf_loader.o, which is used in samples/bpf, this commit refactors the existing tracepoint tracing programs with libbbpf bpf loader. - Adding a tracepoint event and attaching a bpf program to it was done through bpf_program_attach(). - Instead of using the existing BPF MAP definition, MAP definition has been refactored with the new BTF-defined MAP format. Signed-off-by: Daniel T. Lee Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20200823085334.9413-4-danieltimlee@gmail.com

samples/bpf, selftests/bpf: Use bpf_probe_read_kernel

2020-07-21T20:26:26+00:00

A handful of samples and selftests fail to build on s390, because after commit 0ebeea8ca8a4 ("bpf: Restrict bpf_probe_read{, str}() only to archs where they work") bpf_probe_read is not available anymore. Fix by using bpf_probe_read_kernel. Signed-off-by: Ilya Leoshkevich Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20200720114806.88823-1-iii@linux.ibm.com

samples/bpf: Remove compiler warnings

2020-05-13T19:30:50+00:00

Commit 5fbc220862fc ("tools/libpf: Add offsetof/container_of macro in bpf_helpers.h") added macros offsetof/container_of to bpf_helpers.h. Unfortunately, it caused compilation warnings below for a few samples/bpf programs: In file included from /data/users/yhs/work/net-next/samples/bpf/sockex2_kern.c:4: In file included from /data/users/yhs/work/net-next/include/uapi/linux/in.h:24: In file included from /data/users/yhs/work/net-next/include/linux/socket.h:8: In file included from /data/users/yhs/work/net-next/include/linux/uio.h:8: /data/users/yhs/work/net-next/include/linux/kernel.h:992:9: warning: 'container_of' macro redefined [-Wmacro-redefined] ^ /data/users/yhs/work/net-next/tools/lib/bpf/bpf_helpers.h:46:9: note: previous definition is here ^ 1 warning generated. CLANG-bpf samples/bpf/sockex3_kern.o In all these cases, bpf_helpers.h is included first, followed by other standard headers. The macro container_of is defined unconditionally in kernel.h, causing the compiler warning. The fix is to move bpf_helpers.h after standard headers. Signed-off-by: Yonghong Song Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20200513180223.2949987-1-yhs@fb.com

samples/bpf: Use consistent include paths for libbpf

2020-01-21T00:37:45+00:00

Fix all files in samples/bpf to include libbpf header files with the bpf/ prefix, to be consistent with external users of the library. Also ensure that all includes of exported libbpf header files (those that are exported on 'make install' of the library) use bracketed includes instead of quoted. To make sure no new files are introduced that doesn't include the bpf/ prefix in its include, remove tools/lib/bpf from the include path entirely, and use tools/lib instead. Fixes: 6910d7d3867a ("selftests/bpf: Ensure bpf_helper_defs.h are taken from selftests dir") Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Alexei Starovoitov Acked-by: Jesper Dangaard Brouer Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/157952560911.1683545.8795966751309534150.stgit@toke.dk

selftests/bpf: Split off tracing-only helpers into bpf_tracing.h

2019-10-08T21:16:03+00:00

Split-off PT_REGS-related helpers into bpf_tracing.h header. Adjust selftests and samples to include it where necessary. Signed-off-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann Acked-by: John Fastabend Acked-by: Song Liu Link: https://lore.kernel.org/bpf/20191008175942.1769476-5-andriin@fb.com

bpf, samples: don't zero data when not needed

2016-04-15T01:40:42+00:00

Remove the zero initialization in the sample programs where appropriate. Note that this is an optimization which is now possible, old programs still doing the zero initialization are just fine as well. Also, make sure we don't have padding issues when we don't memset() the entire struct anymore. Signed-off-by: Daniel Borkmann Acked-by: Alexei Starovoitov Signed-off-by: David S. Miller

samples/bpf: tracepoint example

2016-04-08T01:04:27+00:00

modify offwaketime to work with sched/sched_switch tracepoint instead of kprobe into finish_task_switch Signed-off-by: Alexei Starovoitov Signed-off-by: David S. Miller