11 Commits
Author SHA1 Message Date
Masami Hiramatsu (Google) 762abbc0d0 fprobe: Use ftrace_regs in fprobe exit handler
Change the fprobe exit handler to use ftrace_regs structure instead of
pt_regs. This also introduce HAVE_FTRACE_REGS_HAVING_PT_REGS which
means the ftrace_regs is including the pt_regs so that ftrace_regs
can provide pt_regs without memory allocation.
Fprobe introduces a new dependency with that.

Signed-off-by: Masami Hiramatsu (Google) <[email protected]>
Acked-by: Heiko Carstens <[email protected]> # s390
Cc: Huacai Chen <[email protected]>
Cc: Alexei Starovoitov <[email protected]>
Cc: Florent Revest <[email protected]>
Cc: bpf <[email protected]>
Cc: Alan Maguire <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: WANG Xuerui <[email protected]>
Cc: Vasily Gorbik <[email protected]>
Cc: Alexander Gordeev <[email protected]>
Cc: Christian Borntraeger <[email protected]>
Cc: Sven Schnelle <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: [email protected]
Cc: "H. Peter Anvin" <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Mathieu Desnoyers <[email protected]>
Cc: Song Liu <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: KP Singh <[email protected]>
Cc: Matt Bobrowski <[email protected]>
Cc: Alexei Starovoitov <[email protected]>
Cc: Daniel Borkmann <[email protected]>
Cc: Andrii Nakryiko <[email protected]>
Cc: Martin KaFai Lau <[email protected]>
Cc: Eduard Zingerman <[email protected]>
Cc: Yonghong Song <[email protected]>
Cc: John Fastabend <[email protected]>
Cc: Stanislav Fomichev <[email protected]>
Cc: Hao Luo <[email protected]>
Cc: Andrew Morton <[email protected]>
Link: https://lore.kernel.org/173518995092.391279.6765116450352977627.stgit@devnote2
Signed-off-by: Steven Rostedt (Google) <[email protected]>
2024-12-26 10:50:03 -05:00
Masami Hiramatsu (Google) 46bc082388 fprobe: Use ftrace_regs in fprobe entry handler
This allows fprobes to be available with CONFIG_DYNAMIC_FTRACE_WITH_ARGS
instead of CONFIG_DYNAMIC_FTRACE_WITH_REGS, then we can enable fprobe
on arm64.

Cc: Alexei Starovoitov <[email protected]>
Cc: Martin KaFai Lau <[email protected]>
Cc: bpf <[email protected]>
Cc: Alexei Starovoitov <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Alan Maguire <[email protected]>
Cc: Mark Rutland <[email protected]>
Link: https://lore.kernel.org/173518994037.391279.2786805566359674586.stgit@devnote2
Signed-off-by: Masami Hiramatsu (Google) <[email protected]>
Acked-by: Florent Revest <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>
2024-12-26 10:50:03 -05:00
Jeff Johnson df216f5752 fprobe: add missing MODULE_DESCRIPTION() macro
make allmodconfig && make W=1 C=1 reports:
WARNING: modpost: missing MODULE_DESCRIPTION() in samples/fprobe/fprobe_example.o

Add the missing invocation of the MODULE_DESCRIPTION() macro.

Link: https://lore.kernel.org/all/[email protected]/

Signed-off-by: Jeff Johnson <[email protected]>
Signed-off-by: Masami Hiramatsu (Google) <[email protected]>
2024-06-12 08:44:27 +09:00
Masami Hiramatsu (Google) cb16330d12 fprobe: Pass return address to the handlers
Pass return address as 'ret_ip' to the fprobe entry and return handlers
so that the fprobe user handler can get the reutrn address without
analyzing arch-dependent pt_regs.

Link: https://lore.kernel.org/all/168507467664.913472.11642316698862778600.stgit@mhiramat.roam.corp.google.com/

Signed-off-by: Masami Hiramatsu (Google) <[email protected]>
2023-06-06 21:39:55 +09:00
Masami Hiramatsu (Google) 39d954200b fprobe: Skip exit_handler if entry_handler returns !0
Skip hooking function return and calling exit_handler if the
entry_handler() returns !0.

Link: https://lkml.kernel.org/r/167526699798.433354.10998365726830117303.stgit@mhiramat.roam.corp.google.com

Cc: Florent Revest <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Will Deacon <[email protected]>
Signed-off-by: Masami Hiramatsu (Google) <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>
2023-03-28 18:52:22 -04:00
Masami Hiramatsu (Google) 76d0de5729 fprobe: Pass entry_data to handlers
Pass the private entry_data to the entry and exit handlers so that
they can share the context data, something like saved function
arguments etc.
User must specify the private entry_data size by @entry_data_size
field before registering the fprobe.

Link: https://lkml.kernel.org/r/167526696173.433354.17408372048319432574.stgit@mhiramat.roam.corp.google.com

Cc: Florent Revest <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Will Deacon <[email protected]>
Signed-off-by: Masami Hiramatsu (Google) <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>
2023-03-28 18:52:22 -04:00
Linus Torvalds b047602d57 Merge tag 'trace-v5.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
 "Fixes and minor clean ups for tracing:

   - Fix memory leak by reverting what was thought to be a double free.

     A static tool had gave a false positive that a double free was
     possible in the error path, but it was actually a different
     location that confused the static analyzer (and those of us that
     reviewed it).

   - Move use of static buffers by ftrace_dump() to a location that can
     be used by kgdb's ftdump(), as it needs it for the same reasons.

   - Clarify in the Kconfig description that function tracing has
     negligible impact on x86, but may have a bit bigger impact on other
     architectures.

   - Remove unnecessary extra semicolon in trace event.

   - Make a local variable static that is used in the fprobes sample

   - Use KSYM_NAME_LEN for length of function in kprobe sample and get
     rid of unneeded macro for the same purpose"

* tag 'trace-v5.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  samples: Use KSYM_NAME_LEN for kprobes
  fprobe/samples: Make sample_probe static
  blk-iocost: tracing: atomic64_read(&ioc->vtime_rate) is assigned an extra semicolon
  ftrace: Be more specific about arch impact when function tracer is enabled
  tracing: Fix sleeping while atomic in kdb ftdump
  tracing/histograms: Fix memory leak problem
2022-07-12 16:17:40 -07:00
sunliming e3655dfa58 fprobe/samples: Make sample_probe static
This symbol is not used outside of fprobe_example.c, so marks it static.

Fixes the following warning:

sparse warnings: (new ones prefixed by >>)
>> samples/fprobe/fprobe_example.c:23:15: sparse: sparse: symbol 'sample_probe'
was not declared. Should it be static?

Link: https://lkml.kernel.org/r/[email protected]

Reported-by: kernel test robot <[email protected]>
Signed-off-by: sunliming <[email protected]>
Acked-by: Masami Hiramatsu (Google) <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>
2022-07-12 16:36:43 -04:00
Masami Hiramatsu (Google) 179a93f74b fprobe, samples: Add module parameter descriptions
Add module parameter descriptions for the fprobe_example module.

Signed-off-by: Masami Hiramatsu (Google) <[email protected]>
Signed-off-by: Andrii Nakryiko <[email protected]>
Link: https://lore.kernel.org/bpf/165602349520.56016.1314423560740428008.stgit@devnote2
2022-06-24 15:23:04 -07:00
Masami Hiramatsu (Google) c88dbbcd88 fprobe, samples: Add use_trace option and show hit/missed counter
Add use_trace option to use trace_printk() instead of pr_info()
so that the handler doesn't involve the RCU operations.
And show the hit and missed counter so that the user can check
how many times the probe handler hit and missed.

Signed-off-by: Masami Hiramatsu (Google) <[email protected]>
Signed-off-by: Daniel Borkmann <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Link: https://lore.kernel.org/bpf/165461826247.280167.11939123218334322352.stgit@devnote2
2022-06-17 21:53:29 +02:00
Masami Hiramatsu 6ee64cc302 fprobe: Add sample program for fprobe
Add a sample program for the fprobe. The sample_fprobe puts a fprobe on
kernel_clone() by default. This dump stack and some called address info
at the function entry and exit.

The sample_fprobe.ko gets 2 parameters.
- symbol: you can specify the comma separated symbols or wildcard symbol
  pattern (in this case you can not use comma)
- stackdump: a bool value to enable or disable stack dump in the fprobe
  handler.

Signed-off-by: Masami Hiramatsu <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>
Tested-by: Steven Rostedt (Google) <[email protected]>
Signed-off-by: Alexei Starovoitov <[email protected]>
Link: https://lore.kernel.org/bpf/164735291987.1084943.4449670993752806840.stgit@devnote2
2022-03-17 20:16:58 -07:00