[GIT PULL v2] hw-breakpoints: Rewrite on top of perf events

Frederic Weisbecker
2009-10-24T14:17:17Z

Hi all,

This is the v2 of the hw-breakpoints API rewrite on top of perf events.
You can find the previous version here:
http://lwn.net/Articles/351922/

Changes in v2:

- Follow the perf "event " rename
- The ptrace regression have been fixed (ptrace breakpoint perf events
weren't released when a task ended)
- Drop the struct hw_breakpoint and store generic fields in
perf_event_attr.
- Separate core and arch specific headers, drop
asm-generic/hw_breakpoint.h and create linux/hw_breakpoint.h
- Use new generic len/type for breakpoint
- Handle off case: when breakpoints api is not supported by an arch
- Use proper in-kernel perf api provided by Arjan.

There are still a lot of things that need to be cleaned, simplified,
improved (ptrace side, the bp api, etc....) I guess these things can
be done incrementally if you agree.

I've also tried to get an arch-independent api. Generic fields for
breakpoints are stored in perf_event_attr structure (type, len, addr).
This needs to be discussed and improved before it becomes a perf
userspace ABI. We need to find a generic enough structure to host
the breakpoints parameters, something that can better fit to most arch
(handling breakpoint ranges in powerpc, etc...).

Thanks.

---

The following patchset are available in the git repository at:

git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing.git
perfevents/hw-breakpoint

Arjan van de Ven (1):
perf/core: Provide a kernel-internal interface to get to performance counters

Frederic Weisbecker (3):
perf/core: Add a callback to perf events
hw-breakpoints: Rewrite the hw-breakpoints layer on top of perf events
hw-breakpoints: Arbitrate access to pmu following registers constraints

Li Zefan (1):
ksym_tracer: Remove KSYM_SELFTEST_ENTRY

Paul Mundt (1):
x86/hw-breakpoints: Actually flush thread breakpoints in flush_thread().

arch/Kconfig | 3 +
arch/x86/include/asm/debugreg.h | 7 -
arch/x86/include/asm/hw_breakpoint.h | 58 +++--
arch/x86/include/asm/processor.h | 12 +-
arch/x86/kernel/hw_breakpoint.c | 376 ++++++++++++++--------
arch/x86/kernel/process.c | 9 +-
arch/x86/kernel/process_32.c | 26 +--
arch/x86/kernel/process_64.c | 26 +--
arch/x86/kernel/ptrace.c | 182 +++++++----
arch/x86/kernel/smpboot.c | 3 -
arch/x86/power/cpu.c | 6 -
include/asm-generic/hw_breakpoint.h | 139 --------
include/linux/hw_breakpoint.h | 131 ++++++++
include/linux/perf_event.h | 37 ++-
kernel/exit.c | 5 +
kernel/hw_breakpoint.c | 595 +++++++++++++++++++++-------------
kernel/perf_event.c | 137 ++++++++-
kernel/trace/trace.h | 1 -
kernel/trace/trace_entries.h | 6 +-
kernel/trace/trace_ksym.c | 126 ++++----
kernel/trace/trace_selftest.c | 2 +-
21 files changed, 1154 insertions(+), 733 deletions(-)
delete mode 100644 include/asm-generic/hw_breakpoint.h
create mode 100644 include/linux/hw_breakpoint.h