mbox series

[PATCHv3,bpf-next,0/7] uprobe: uretprobe speed up

Message ID 20240421194206.1010934-1-jolsa@kernel.org (mailing list archive)
Headers show
Series uprobe: uretprobe speed up | expand

Message

Jiri Olsa April 21, 2024, 7:41 p.m. UTC
hi,
as part of the effort on speeding up the uprobes [0] coming with
return uprobe optimization by using syscall instead of the trap
on the uretprobe trampoline.

The speed up depends on instruction type that uprobe is installed
and depends on specific HW type, please check patch 1 for details.

Patches 1-6 are based on bpf-next/master, but path 1 and 2 are
apply-able on linux-trace.git tree probes/for-next branch.
Patch 7 is based on man-pages master.

v3 changes:
  - added source ip check if the uretprobe syscall is called from
    trampoline and sending SIGILL to process if it's not
  - keep x86 compat process to use standard breakpoint
  - split syscall wiring into separate change
  - ran ltp and syzkaller locally, no issues found [Masami]
  - building uprobe_compat binary in selftests which breaks
    CI atm because of missing 32-bit delve packages, I will
    need to fix that in separate changes once this is acked
  - added man page change
  - there were several changes so I removed acks [Oleg Andrii]

Also available at:
  https://git.kernel.org/pub/scm/linux/kernel/git/jolsa/perf.git
  uretprobe_syscall

thanks,
jirka


Notes to check list items in Documentation/process/adding-syscalls.rst:

- System Call Alternatives
  New syscall seems like the best way in here, becase we need
  just to quickly enter kernel with no extra arguments processing,
  which we'd need to do if we decided to use another syscall.

- Designing the API: Planning for Extension
  The uretprobe syscall is very specific and most likely won't be
  extended in the future.

  At the moment it does not take any arguments and even if it does
  in future, it's allowed to be called only from trampoline prepared
  by kernel, so there'll be no broken user.

- Designing the API: Other Considerations
  N/A because uretprobe syscall does not return reference to kernel
  object.

- Proposing the API
  Wiring up of the uretprobe system call si in separate change,
  selftests and man page changes are part of the patchset.

- Generic System Call Implementation
  There's no CONFIG option for the new functionality because it
  keeps the same behaviour from the user POV.

- x86 System Call Implementation
  It's 64-bit syscall only.

- Compatibility System Calls (Generic)
  N/A uretprobe syscall has no arguments and is not supported
  for compat processes.

- Compatibility System Calls (x86)
  N/A uretprobe syscall is not supported for compat processes.

- System Calls Returning Elsewhere
  N/A.

- Other Details
  N/A.

- Testing
  Adding new bpf selftests and ran ltp on top of this change.

- Man Page
  Attached.

- Do not call System Calls in the Kernel
  N/A.


[0] https://lore.kernel.org/bpf/ZeCXHKJ--iYYbmLj@krava/
---
Jiri Olsa (6):
      uprobe: Wire up uretprobe system call
      uprobe: Add uretprobe syscall to speed up return probe
      selftests/bpf: Add uretprobe syscall test for regs integrity
      selftests/bpf: Add uretprobe syscall test for regs changes
      selftests/bpf: Add uretprobe syscall call from user space test
      selftests/bpf: Add uretprobe compat test

 arch/x86/entry/syscalls/syscall_64.tbl                    |   1 +
 arch/x86/kernel/uprobes.c                                 | 115 ++++++++++++++++++++++++++++++
 include/linux/syscalls.h                                  |   2 +
 include/linux/uprobes.h                                   |   3 +
 include/uapi/asm-generic/unistd.h                         |   5 +-
 kernel/events/uprobes.c                                   |  24 +++++--
 kernel/sys_ni.c                                           |   2 +
 tools/include/linux/compiler.h                            |   4 ++
 tools/testing/selftests/bpf/.gitignore                    |   1 +
 tools/testing/selftests/bpf/Makefile                      |   6 +-
 tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c     | 123 +++++++++++++++++++++++++++++++-
 tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c   | 362 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 tools/testing/selftests/bpf/progs/uprobe_syscall.c        |  15 ++++
 tools/testing/selftests/bpf/progs/uprobe_syscall_call.c   |  15 ++++
 tools/testing/selftests/bpf/progs/uprobe_syscall_compat.c |  13 ++++
 15 files changed, 681 insertions(+), 10 deletions(-)
 create mode 100644 tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c
 create mode 100644 tools/testing/selftests/bpf/progs/uprobe_syscall.c
 create mode 100644 tools/testing/selftests/bpf/progs/uprobe_syscall_call.c
 create mode 100644 tools/testing/selftests/bpf/progs/uprobe_syscall_compat.c


Jiri Olsa (1):
      man2: Add uretprobe syscall page

 man2/uretprobe.2 | 40 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)
 create mode 100644 man2/uretprobe.2

Comments

Masami Hiramatsu (Google) April 22, 2024, 3:09 p.m. UTC | #1
Hi Jiri,

On Sun, 21 Apr 2024 21:41:59 +0200
Jiri Olsa <jolsa@kernel.org> wrote:

> hi,
> as part of the effort on speeding up the uprobes [0] coming with
> return uprobe optimization by using syscall instead of the trap
> on the uretprobe trampoline.
> 
> The speed up depends on instruction type that uprobe is installed
> and depends on specific HW type, please check patch 1 for details.
> 
> Patches 1-6 are based on bpf-next/master, but path 1 and 2 are
> apply-able on linux-trace.git tree probes/for-next branch.
> Patch 7 is based on man-pages master.

Thanks for updated! I reviewed the series and just except for the
manpage, it looks good to me.

Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>

for the series.
If Linux API maintainers are OK, I can pick this in probes/for-next.
(BTW, who will pick the manpage patch?)

Thank you,

> 
> v3 changes:
>   - added source ip check if the uretprobe syscall is called from
>     trampoline and sending SIGILL to process if it's not
>   - keep x86 compat process to use standard breakpoint
>   - split syscall wiring into separate change
>   - ran ltp and syzkaller locally, no issues found [Masami]
>   - building uprobe_compat binary in selftests which breaks
>     CI atm because of missing 32-bit delve packages, I will
>     need to fix that in separate changes once this is acked
>   - added man page change
>   - there were several changes so I removed acks [Oleg Andrii]
> 
> Also available at:
>   https://git.kernel.org/pub/scm/linux/kernel/git/jolsa/perf.git
>   uretprobe_syscall
> 
> thanks,
> jirka
> 
> 
> Notes to check list items in Documentation/process/adding-syscalls.rst:
> 
> - System Call Alternatives
>   New syscall seems like the best way in here, becase we need
>   just to quickly enter kernel with no extra arguments processing,
>   which we'd need to do if we decided to use another syscall.
> 
> - Designing the API: Planning for Extension
>   The uretprobe syscall is very specific and most likely won't be
>   extended in the future.
> 
>   At the moment it does not take any arguments and even if it does
>   in future, it's allowed to be called only from trampoline prepared
>   by kernel, so there'll be no broken user.
> 
> - Designing the API: Other Considerations
>   N/A because uretprobe syscall does not return reference to kernel
>   object.
> 
> - Proposing the API
>   Wiring up of the uretprobe system call si in separate change,
>   selftests and man page changes are part of the patchset.
> 
> - Generic System Call Implementation
>   There's no CONFIG option for the new functionality because it
>   keeps the same behaviour from the user POV.
> 
> - x86 System Call Implementation
>   It's 64-bit syscall only.
> 
> - Compatibility System Calls (Generic)
>   N/A uretprobe syscall has no arguments and is not supported
>   for compat processes.
> 
> - Compatibility System Calls (x86)
>   N/A uretprobe syscall is not supported for compat processes.
> 
> - System Calls Returning Elsewhere
>   N/A.
> 
> - Other Details
>   N/A.
> 
> - Testing
>   Adding new bpf selftests and ran ltp on top of this change.
> 
> - Man Page
>   Attached.
> 
> - Do not call System Calls in the Kernel
>   N/A.
> 
> 
> [0] https://lore.kernel.org/bpf/ZeCXHKJ--iYYbmLj@krava/
> ---
> Jiri Olsa (6):
>       uprobe: Wire up uretprobe system call
>       uprobe: Add uretprobe syscall to speed up return probe
>       selftests/bpf: Add uretprobe syscall test for regs integrity
>       selftests/bpf: Add uretprobe syscall test for regs changes
>       selftests/bpf: Add uretprobe syscall call from user space test
>       selftests/bpf: Add uretprobe compat test
> 
>  arch/x86/entry/syscalls/syscall_64.tbl                    |   1 +
>  arch/x86/kernel/uprobes.c                                 | 115 ++++++++++++++++++++++++++++++
>  include/linux/syscalls.h                                  |   2 +
>  include/linux/uprobes.h                                   |   3 +
>  include/uapi/asm-generic/unistd.h                         |   5 +-
>  kernel/events/uprobes.c                                   |  24 +++++--
>  kernel/sys_ni.c                                           |   2 +
>  tools/include/linux/compiler.h                            |   4 ++
>  tools/testing/selftests/bpf/.gitignore                    |   1 +
>  tools/testing/selftests/bpf/Makefile                      |   6 +-
>  tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c     | 123 +++++++++++++++++++++++++++++++-
>  tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c   | 362 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  tools/testing/selftests/bpf/progs/uprobe_syscall.c        |  15 ++++
>  tools/testing/selftests/bpf/progs/uprobe_syscall_call.c   |  15 ++++
>  tools/testing/selftests/bpf/progs/uprobe_syscall_compat.c |  13 ++++
>  15 files changed, 681 insertions(+), 10 deletions(-)
>  create mode 100644 tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c
>  create mode 100644 tools/testing/selftests/bpf/progs/uprobe_syscall.c
>  create mode 100644 tools/testing/selftests/bpf/progs/uprobe_syscall_call.c
>  create mode 100644 tools/testing/selftests/bpf/progs/uprobe_syscall_compat.c
> 
> 
> Jiri Olsa (1):
>       man2: Add uretprobe syscall page
> 
>  man2/uretprobe.2 | 40 ++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 40 insertions(+)
>  create mode 100644 man2/uretprobe.2
Jiri Olsa April 22, 2024, 8:25 p.m. UTC | #2
On Tue, Apr 23, 2024 at 12:09:43AM +0900, Masami Hiramatsu wrote:
> Hi Jiri,
> 
> On Sun, 21 Apr 2024 21:41:59 +0200
> Jiri Olsa <jolsa@kernel.org> wrote:
> 
> > hi,
> > as part of the effort on speeding up the uprobes [0] coming with
> > return uprobe optimization by using syscall instead of the trap
> > on the uretprobe trampoline.
> > 
> > The speed up depends on instruction type that uprobe is installed
> > and depends on specific HW type, please check patch 1 for details.
> > 
> > Patches 1-6 are based on bpf-next/master, but path 1 and 2 are
> > apply-able on linux-trace.git tree probes/for-next branch.
> > Patch 7 is based on man-pages master.
> 
> Thanks for updated! I reviewed the series and just except for the
> manpage, it looks good to me.
> 
> Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> 
> for the series.
> If Linux API maintainers are OK, I can pick this in probes/for-next.

great, thanks

> (BTW, who will pick the manpage patch?)

ugh, I cc-ed linux-api but not linux-man@vger.kernel.org
I'll add that for new version

jirka

> 
> Thank you,
> 
> > 
> > v3 changes:
> >   - added source ip check if the uretprobe syscall is called from
> >     trampoline and sending SIGILL to process if it's not
> >   - keep x86 compat process to use standard breakpoint
> >   - split syscall wiring into separate change
> >   - ran ltp and syzkaller locally, no issues found [Masami]
> >   - building uprobe_compat binary in selftests which breaks
> >     CI atm because of missing 32-bit delve packages, I will
> >     need to fix that in separate changes once this is acked
> >   - added man page change
> >   - there were several changes so I removed acks [Oleg Andrii]
> > 
> > Also available at:
> >   https://git.kernel.org/pub/scm/linux/kernel/git/jolsa/perf.git
> >   uretprobe_syscall
> > 
> > thanks,
> > jirka
> > 
> > 
> > Notes to check list items in Documentation/process/adding-syscalls.rst:
> > 
> > - System Call Alternatives
> >   New syscall seems like the best way in here, becase we need
> >   just to quickly enter kernel with no extra arguments processing,
> >   which we'd need to do if we decided to use another syscall.
> > 
> > - Designing the API: Planning for Extension
> >   The uretprobe syscall is very specific and most likely won't be
> >   extended in the future.
> > 
> >   At the moment it does not take any arguments and even if it does
> >   in future, it's allowed to be called only from trampoline prepared
> >   by kernel, so there'll be no broken user.
> > 
> > - Designing the API: Other Considerations
> >   N/A because uretprobe syscall does not return reference to kernel
> >   object.
> > 
> > - Proposing the API
> >   Wiring up of the uretprobe system call si in separate change,
> >   selftests and man page changes are part of the patchset.
> > 
> > - Generic System Call Implementation
> >   There's no CONFIG option for the new functionality because it
> >   keeps the same behaviour from the user POV.
> > 
> > - x86 System Call Implementation
> >   It's 64-bit syscall only.
> > 
> > - Compatibility System Calls (Generic)
> >   N/A uretprobe syscall has no arguments and is not supported
> >   for compat processes.
> > 
> > - Compatibility System Calls (x86)
> >   N/A uretprobe syscall is not supported for compat processes.
> > 
> > - System Calls Returning Elsewhere
> >   N/A.
> > 
> > - Other Details
> >   N/A.
> > 
> > - Testing
> >   Adding new bpf selftests and ran ltp on top of this change.
> > 
> > - Man Page
> >   Attached.
> > 
> > - Do not call System Calls in the Kernel
> >   N/A.
> > 
> > 
> > [0] https://lore.kernel.org/bpf/ZeCXHKJ--iYYbmLj@krava/
> > ---
> > Jiri Olsa (6):
> >       uprobe: Wire up uretprobe system call
> >       uprobe: Add uretprobe syscall to speed up return probe
> >       selftests/bpf: Add uretprobe syscall test for regs integrity
> >       selftests/bpf: Add uretprobe syscall test for regs changes
> >       selftests/bpf: Add uretprobe syscall call from user space test
> >       selftests/bpf: Add uretprobe compat test
> > 
> >  arch/x86/entry/syscalls/syscall_64.tbl                    |   1 +
> >  arch/x86/kernel/uprobes.c                                 | 115 ++++++++++++++++++++++++++++++
> >  include/linux/syscalls.h                                  |   2 +
> >  include/linux/uprobes.h                                   |   3 +
> >  include/uapi/asm-generic/unistd.h                         |   5 +-
> >  kernel/events/uprobes.c                                   |  24 +++++--
> >  kernel/sys_ni.c                                           |   2 +
> >  tools/include/linux/compiler.h                            |   4 ++
> >  tools/testing/selftests/bpf/.gitignore                    |   1 +
> >  tools/testing/selftests/bpf/Makefile                      |   6 +-
> >  tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c     | 123 +++++++++++++++++++++++++++++++-
> >  tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c   | 362 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> >  tools/testing/selftests/bpf/progs/uprobe_syscall.c        |  15 ++++
> >  tools/testing/selftests/bpf/progs/uprobe_syscall_call.c   |  15 ++++
> >  tools/testing/selftests/bpf/progs/uprobe_syscall_compat.c |  13 ++++
> >  15 files changed, 681 insertions(+), 10 deletions(-)
> >  create mode 100644 tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c
> >  create mode 100644 tools/testing/selftests/bpf/progs/uprobe_syscall.c
> >  create mode 100644 tools/testing/selftests/bpf/progs/uprobe_syscall_call.c
> >  create mode 100644 tools/testing/selftests/bpf/progs/uprobe_syscall_compat.c
> > 
> > 
> > Jiri Olsa (1):
> >       man2: Add uretprobe syscall page
> > 
> >  man2/uretprobe.2 | 40 ++++++++++++++++++++++++++++++++++++++++
> >  1 file changed, 40 insertions(+)
> >  create mode 100644 man2/uretprobe.2
> 
> 
> -- 
> Masami Hiramatsu (Google) <mhiramat@kernel.org>