x86, bts: improve help text for BTS config

Improve the help text of the X86_PTRACE_BTS config.
Make X86_DS invisible and depend on X86_PTRACE_BTS.

Reported-by: Roland Dreier <rdreier@cisco.com>
Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Markus Metzger 2008-10-17 09:09:27 +02:00 committed by Ingo Molnar
parent 71cced6eb0
commit 531f6ed7de

View file

@ -513,19 +513,19 @@ config CPU_SUP_UMC_32
If unsure, say N.
config X86_DS
bool "Debug Store support"
default y
help
Add support for Debug Store.
This allows the kernel to provide a memory buffer to the hardware
to store various profiling and tracing events.
def_bool X86_PTRACE_BTS
depends on X86_DEBUGCTLMSR
config X86_PTRACE_BTS
bool "ptrace interface to Branch Trace Store"
bool "Branch Trace Store"
default y
depends on (X86_DS && X86_DEBUGCTLMSR)
depends on X86_DEBUGCTLMSR
help
Add a ptrace interface to allow collecting an execution trace
of the traced task.
This collects control flow changes in a (cyclic) buffer and allows
debuggers to fill in the gaps and show an execution trace of the debuggee.
This adds a ptrace interface to the hardware's branch trace store.
Debuggers may use it to collect an execution trace of the debugged
application in order to answer the question 'how did I get here?'.
Debuggers may trace user mode as well as kernel mode.
Say Y unless there is no application development on this machine
and you want to save a small amount of code size.