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>

1 files changed, 12 insertions, 12 deletions

diff --git a/arch/x86/Kconfig.cpu b/arch/x86/Kconfig.cpu
index 0b7c4a3f0651..b815664fe370 100644
--- a/arch/x86/Kconfig.cpu
+++ b/arch/x86/Kconfig.cpu
@@ -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.