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* [PATCHv2 0/5] perf/hw_breakpoint: Fix breakpoint modify
@ 2018-08-09 12:03 Jiri Olsa
  2018-08-09 12:03 ` [PATCH 1/5] perf tests: Add breakpoint modify tests Jiri Olsa
                   ` (5 more replies)
  0 siblings, 6 replies; 15+ messages in thread
From: Jiri Olsa @ 2018-08-09 12:03 UTC (permalink / raw)
  To: Arnaldo Carvalho de Melo
  Cc: lkml, Ingo Molnar, Namhyung Kim, David Ahern, Alexander Shishkin,
	Peter Zijlstra, Milind Chabbi, Oleg Nesterov,
	Frederic Weisbecker

hi,
Milind reported that modify_user_hw_breakpoint wouldn't
allow the breakpoint changing if the new attr had 'disabled'
set to true.

I found a case where it actualy prevents ptrace user interface
to change the breakpoint. It's described in patch 1 as perf test,
patch 2 is the breakpoint code fix.

I ran strace tests, nothing (new) broken there..

v2 changes:
  - added Oleg's ack for patch 2
  - added new changes based on Oleg's questions
    plus new test code

thanks,
jirka

---
Jiri Olsa (5):
      perf tests: Add breakpoint modify tests
      perf/hw_breakpoint: Modify breakpoint even if the new attr has disabled set
      perf/hw_breakpoint: Remove superfluous bp->attr.disabled = 0
      perf/hw_breakpoint: Set breakpoint as disabled in modify_user_hw_breakpoint error path
      perf/hw_breakpoint: Add fallback code for ptrace_set_breakpoint_addr

 arch/x86/kernel/ptrace.c                 |   5 +++
 kernel/events/hw_breakpoint.c            |  15 +++++----
 tools/perf/arch/x86/include/arch-tests.h |   1 +
 tools/perf/arch/x86/tests/Build          |   1 +
 tools/perf/arch/x86/tests/arch-tests.c   |   6 ++++
 tools/perf/arch/x86/tests/bp-modify.c    | 213 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 6 files changed, 235 insertions(+), 6 deletions(-)
 create mode 100644 tools/perf/arch/x86/tests/bp-modify.c

^ permalink raw reply	[flat|nested] 15+ messages in thread
* [PATCHv3 0/5] perf/hw_breakpoint: Fix breakpoint modify
@ 2018-08-10 10:47 Jiri Olsa
  2018-08-10 10:47 ` [PATCH 1/5] perf tests: Add breakpoint modify tests Jiri Olsa
  0 siblings, 1 reply; 15+ messages in thread
From: Jiri Olsa @ 2018-08-10 10:47 UTC (permalink / raw)
  To: Arnaldo Carvalho de Melo
  Cc: lkml, Ingo Molnar, Namhyung Kim, David Ahern, Alexander Shishkin,
	Peter Zijlstra, Milind Chabbi, Oleg Nesterov,
	Frederic Weisbecker

hi,
Milind reported that modify_user_hw_breakpoint wouldn't
allow the breakpoint changing if the new attr had 'disabled'
set to true.

I found a case where it actualy prevents ptrace user interface
to change the breakpoint. It's described in patch 1 as perf test,
patch 2 is the breakpoint code fix.

I ran strace tests, nothing (new) broken there..

v3 changes:
  - added Oleg's ack for patch 3
  - new patches 4,5 based on Oleg's suggestions
    replacing the v2 fallback approach by enabling
    the event directly after failed modification

v2 changes:
  - added Oleg's ack for patch 2
  - added new changes based on Oleg's questions
    plus new test code

thanks,
jirka

---
Jiri Olsa (5):
      perf tests: Add breakpoint modify tests
      perf/hw_breakpoint: Modify breakpoint even if the new attr has disabled set
      perf/hw_breakpoint: Remove superfluous bp->attr.disabled = 0
      perf/hw_breakpoint: Enable breakpoint in modify_user_hw_breakpoint
      perf/hw_breakpoint: Simplify breakpoint enable in perf_event_modify_breakpoint

 kernel/events/core.c                     |  11 ++-----
 kernel/events/hw_breakpoint.c            |  13 ++++----
 tools/perf/arch/x86/include/arch-tests.h |   1 +
 tools/perf/arch/x86/tests/Build          |   1 +
 tools/perf/arch/x86/tests/arch-tests.c   |   6 ++++
 tools/perf/arch/x86/tests/bp-modify.c    | 213 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 6 files changed, 230 insertions(+), 15 deletions(-)
 create mode 100644 tools/perf/arch/x86/tests/bp-modify.c

^ permalink raw reply	[flat|nested] 15+ messages in thread
* [PATCHv4 0/5] perf/hw_breakpoint: Fix breakpoint modify
@ 2018-08-27  9:12 Jiri Olsa
  2018-08-27  9:12 ` [PATCH 1/5] perf tests: Add breakpoint modify tests Jiri Olsa
  0 siblings, 1 reply; 15+ messages in thread
From: Jiri Olsa @ 2018-08-27  9:12 UTC (permalink / raw)
  To: Ingo Molnar, Peter Zijlstra, Arnaldo Carvalho de Melo
  Cc: lkml, Namhyung Kim, David Ahern, Alexander Shishkin,
	Milind Chabbi, Oleg Nesterov

hi,
Milind reported that modify_user_hw_breakpoint wouldn't
allow the breakpoint changing if the new attr had 'disabled'
set to true.

I found a case where it actualy prevents ptrace user interface
to change the breakpoint. It's described in patch 1 as perf test,
patch 2 is the breakpoint code fix.

I ran strace tests, nothing (new) broken there..

v4 changes:
  - added Oleg's and Frederic's acks

v3 changes:
  - added Oleg's ack for patch 3
  - new patches 4,5 based on Oleg's suggestions
    replacing the v2 fallback approach by enabling
    the event directly after failed modification

v2 changes:
  - added Oleg's ack for patch 2
  - added new changes based on Oleg's questions
    plus new test code

thanks,
jirka

---
Jiri Olsa (5):
      perf tests: Add breakpoint modify tests
      perf/hw_breakpoint: Modify breakpoint even if the new attr has disabled set
      perf/hw_breakpoint: Remove superfluous bp->attr.disabled = 0
      perf/hw_breakpoint: Enable breakpoint in modify_user_hw_breakpoint
      perf/hw_breakpoint: Simplify breakpoint enable in perf_event_modify_breakpoint

 kernel/events/core.c                     |  11 ++-----
 kernel/events/hw_breakpoint.c            |  13 ++++----
 tools/perf/arch/x86/include/arch-tests.h |   1 +
 tools/perf/arch/x86/tests/Build          |   1 +
 tools/perf/arch/x86/tests/arch-tests.c   |   6 ++++
 tools/perf/arch/x86/tests/bp-modify.c    | 213 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 6 files changed, 230 insertions(+), 15 deletions(-)
 create mode 100644 tools/perf/arch/x86/tests/bp-modify.c

^ permalink raw reply	[flat|nested] 15+ messages in thread

end of thread, other threads:[~2018-08-28 14:39 UTC | newest]

Thread overview: 15+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-08-09 12:03 [PATCHv2 0/5] perf/hw_breakpoint: Fix breakpoint modify Jiri Olsa
2018-08-09 12:03 ` [PATCH 1/5] perf tests: Add breakpoint modify tests Jiri Olsa
2018-08-09 12:03 ` [PATCH 2/5] perf/hw_breakpoint: Modify breakpoint even if the new attr has disabled set Jiri Olsa
2018-08-09 12:03 ` [PATCH 3/5] perf/hw_breakpoint: Remove superfluous bp->attr.disabled = 0 Jiri Olsa
2018-08-09 13:59   ` Oleg Nesterov
2018-08-09 12:03 ` [PATCH 4/5] perf/hw_breakpoint: Set breakpoint as disabled in modify_user_hw_breakpoint error path Jiri Olsa
2018-08-09 14:17   ` Oleg Nesterov
2018-08-09 16:30     ` Jiri Olsa
2018-08-28 14:29       ` Arnaldo Carvalho de Melo
2018-08-28 14:38         ` Jiri Olsa
2018-08-28 14:39           ` Arnaldo Carvalho de Melo
2018-08-09 12:03 ` [PATCH 5/5] perf/hw_breakpoint: Add fallback code for ptrace_set_breakpoint_addr Jiri Olsa
2018-08-28 14:25 ` [PATCHv2 0/5] perf/hw_breakpoint: Fix breakpoint modify Arnaldo Carvalho de Melo
2018-08-10 10:47 [PATCHv3 " Jiri Olsa
2018-08-10 10:47 ` [PATCH 1/5] perf tests: Add breakpoint modify tests Jiri Olsa
2018-08-27  9:12 [PATCHv4 0/5] perf/hw_breakpoint: Fix breakpoint modify Jiri Olsa
2018-08-27  9:12 ` [PATCH 1/5] perf tests: Add breakpoint modify tests Jiri Olsa

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