[PATCHv2 0/8] x86/ftrace: Add direct batch interface

From: Jiri Olsa
Date: Fri Oct 08 2021 - 05:13:46 EST


hi,
adding interface to maintain multiple direct functions
within single calls. It's a base for follow up bpf batch
attach functionality.

New interface:

int register_ftrace_direct_multi(struct ftrace_ops *ops, unsigned long addr)
int unregister_ftrace_direct_multi(struct ftrace_ops *ops)
int modify_ftrace_direct_multi(struct ftrace_ops *ops, unsigned long addr)

that allows to register/unregister/modify direct function 'addr'
with struct ftrace_ops object. The ops filter can be updated
before with ftrace_set_filter_ip calls

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

Also available at (based on Steven's ftrace/core branch):
https://git.kernel.org/pub/scm/linux/kernel/git/jolsa/perf.git
ftrace/direct

v2 changes:
- added comments to API functions
- move common cleanup code to new remove_direct_functions_hash
function
- added addr argument to unregister_ftrace_direct_multi API,
to properly cleanup direct_functions hash
- added missing unregister_ftrace_direct call to trampoline/graph
selftest
- added comment to modify_ftrace_direct_multi about non-callback
gap between ftrace_shutdown and ftrace_startup

thanks,
jirka


---
Jiri Olsa (6):
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

Steven Rostedt (VMware) (2):
x86/ftrace: Remove fault protection code in prepare_ftrace_return
x86/ftrace: Make function graph use ftrace directly

arch/x86/include/asm/ftrace.h | 9 +++-
arch/x86/kernel/ftrace.c | 71 +++++++++++++++---------------
arch/x86/kernel/ftrace_64.S | 30 +------------
include/linux/ftrace.h | 26 +++++++++++
kernel/trace/fgraph.c | 6 ++-
kernel/trace/ftrace.c | 268 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++------------
kernel/trace/trace_selftest.c | 54 ++++++++++++++++++++++-
samples/ftrace/Makefile | 1 +
samples/ftrace/ftrace-direct-multi.c | 52 ++++++++++++++++++++++
9 files changed, 420 insertions(+), 97 deletions(-)
create mode 100644 samples/ftrace/ftrace-direct-multi.c