hi,
sending new version of batch attach support, previous post
is in here [1].
The previous post could not assign multi trampoline on top
of regular trampolines. This patchset is trying to address
that, plus it has other fixes from last post.
This patchset contains:
1) patches (1-4) that fix the ftrace graph tracing over the function
with direct trampolines attached
2) patches (5-8) that add batch interface for ftrace direct function
register/unregister/modify
3) patches (9-27) that add support to attach BPF program to multiple
functions
The current functionality in nutshell:
- allows to create 'multi trampoline' and use it to attach single
program over multiple functions
- it's possible to attach 'multi trampoline' on top of functions
with attached trampoline
- once 'multi trampoline' is created, the functions are locked and we:
- do not allow to attach another 'multi trampoline' that intersects
partially with already attached multi trampoline
- do not allow to attach another standard trampoline on any function
from 'multi trampoline'
- allow to reuse 'multi trampoline' and attach another multi program
in it
These limitations are enforced to keep the implementation simple,
because having multi trampolines to intersect would bring more
complexity plus more ftrace direct API changes.
It'd be probably possible allowing to attach another standard
trampoline to 'multi trampoline' if needed.
v4 other changes from previous review:
- more detailed changelogs in several patches
- removed 'ip' argument assumption in verifier code,
because we now have bpf_get_func_ip helper
- moved 'multi_func' under other bools in bpf.h [Yonghong]
- used static linker in selftests [Andrii]
- added more tests
- added btf__find_by_glob_kind for simplified glob matching
instead of the previous glibc glob matching [Andrii]
- used '__ksym' instead of resolving test functions [Andrii]
- I kept the single BPF_F_MULTI_FUNC flag instead of adding
new multi prog type, because it'd be more complex
- removed superfluous BPF_PROG_TYPE_TRACING/multi_func check
from check_multi_prog_type [Yonghong]
- kept link_create.iter_info_len as BPF_LINK_CREATE_LAST_FIELD
[Yonghong]
- define FTRACE_OPS_GRAPH_STUB 0 to make code look sane [Andrii]
- removed BPF_LINK_UPDATE interface
Also available at:
https://git.kernel.org/pub/scm/linux/kernel/git/jolsa/perf.git
bpf/batch
thanks,
jirka
[1] https://lore.kernel.org/bpf/20210605111034.1810858-1-jolsa@xxxxxxxxxx/
---
Jiri Olsa (25):
x86/ftrace: Remove extra orig rax move
tracing: Add trampoline/graph selftest
ftrace: Add ftrace_add_rec_direct function
ftrace: Add multi direct register/unregister interface
ftrace: Add multi direct modify interface
ftrace/samples: Add multi direct interface test module
bpf: Add support to load multi func tracing program
bpf: Add struct bpf_tramp_node layer
bpf: Factor out bpf_trampoline_init function
bpf: Factor out __bpf_trampoline_lookup function
bpf: Factor out __bpf_trampoline_put function
bpf: Change bpf_trampoline_get to return error pointer
bpf, x64: Allow to use caller address from stack
bpf: Add bpf_trampoline_multi_get/put functions
bpf: Add multi trampoline attach support
bpf, x64: Store properly return value for trampoline with multi func programs
bpf: Attach multi trampoline with ftrace_ops
libbpf: Add btf__find_by_glob_kind function
libbpf: Add support to link multi func tracing program
selftests/bpf: Add fentry multi func test
selftests/bpf: Add fexit multi func test
selftests/bpf: Add fentry/fexit multi func test
selftests/bpf: Add mixed multi func test
selftests/bpf: Add attach multi func test
selftests/bpf: Add ret_mod multi func test
Steven Rostedt (VMware) (2):
x86/ftrace: Remove fault protection code in prepare_ftrace_return
x86/ftrace: Make function graph use ftrace directly
arch/x86/Makefile | 7 +++
arch/x86/boot/compressed/Makefile | 4 ++
arch/x86/include/asm/ftrace.h | 9 +++-
arch/x86/kernel/ftrace.c | 71 +++++++++++++------------
arch/x86/kernel/ftrace_64.S | 30 +----------
arch/x86/net/bpf_jit_comp.c | 53 +++++++++++++++----
drivers/firmware/efi/libstub/Makefile | 3 ++
include/linux/bpf.h | 44 ++++++++++++++--
include/linux/ftrace.h | 22 ++++++++
include/uapi/linux/bpf.h | 12 +++++
kernel/bpf/core.c | 2 +
kernel/bpf/syscall.c | 163 +++++++++++++++++++++++++++++++++++++++++++++++++++++----
kernel/bpf/trampoline.c | 400 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++--------------
kernel/bpf/verifier.c | 7 +--
kernel/trace/fgraph.c | 6 ++-
kernel/trace/ftrace.c | 214 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++---------
kernel/trace/trace_selftest.c | 49 ++++++++++++++++-
samples/ftrace/Makefile | 1 +
samples/ftrace/ftrace-direct-multi.c | 52 ++++++++++++++++++
tools/include/uapi/linux/bpf.h | 12 +++++
tools/lib/bpf/bpf.c | 8 +++
tools/lib/bpf/bpf.h | 6 ++-
tools/lib/bpf/btf.c | 80 ++++++++++++++++++++++++++++
tools/lib/bpf/btf.h | 3 ++
tools/lib/bpf/libbpf.c | 72 +++++++++++++++++++++++++
tools/testing/selftests/bpf/Makefile | 8 ++-
tools/testing/selftests/bpf/prog_tests/modify_return.c | 114 ++++++++++++++++++++++++++++++++++++++--
tools/testing/selftests/bpf/prog_tests/multi_attach_check_test.c | 115 ++++++++++++++++++++++++++++++++++++++++
tools/testing/selftests/bpf/prog_tests/multi_fentry_fexit_test.c | 32 ++++++++++++
tools/testing/selftests/bpf/prog_tests/multi_fentry_test.c | 30 +++++++++++
tools/testing/selftests/bpf/prog_tests/multi_fexit_test.c | 31 +++++++++++
tools/testing/selftests/bpf/prog_tests/multi_mixed_test.c | 34 ++++++++++++
tools/testing/selftests/bpf/progs/multi_attach_check.c | 36 +++++++++++++
tools/testing/selftests/bpf/progs/multi_attach_check_extra1.c | 12 +++++
tools/testing/selftests/bpf/progs/multi_attach_check_extra2.c | 12 +++++
tools/testing/selftests/bpf/progs/multi_check.c | 85 ++++++++++++++++++++++++++++++
tools/testing/selftests/bpf/progs/multi_fentry.c | 17 ++++++
tools/testing/selftests/bpf/progs/multi_fentry_fexit.c | 28 ++++++++++
tools/testing/selftests/bpf/progs/multi_fexit.c | 20 +++++++
tools/testing/selftests/bpf/progs/multi_mixed.c | 43 +++++++++++++++
tools/testing/selftests/bpf/progs/multi_modify_return.c | 17 ++++++
41 files changed, 1799 insertions(+), 165 deletions(-)
create mode 100644 samples/ftrace/ftrace-direct-multi.c
create mode 100644 tools/testing/selftests/bpf/prog_tests/multi_attach_check_test.c
create mode 100644 tools/testing/selftests/bpf/prog_tests/multi_fentry_fexit_test.c
create mode 100644 tools/testing/selftests/bpf/prog_tests/multi_fentry_test.c
create mode 100644 tools/testing/selftests/bpf/prog_tests/multi_fexit_test.c
create mode 100644 tools/testing/selftests/bpf/prog_tests/multi_mixed_test.c
create mode 100644 tools/testing/selftests/bpf/progs/multi_attach_check.c
create mode 100644 tools/testing/selftests/bpf/progs/multi_attach_check_extra1.c
create mode 100644 tools/testing/selftests/bpf/progs/multi_attach_check_extra2.c
create mode 100644 tools/testing/selftests/bpf/progs/multi_check.c
create mode 100644 tools/testing/selftests/bpf/progs/multi_fentry.c
create mode 100644 tools/testing/selftests/bpf/progs/multi_fentry_fexit.c
create mode 100644 tools/testing/selftests/bpf/progs/multi_fexit.c
create mode 100644 tools/testing/selftests/bpf/progs/multi_mixed.c
create mode 100644 tools/testing/selftests/bpf/progs/multi_modify_return.c
