Merge branch 'perf/nmi' into perf/core

[pandora-kernel.git] / lib / Kconfig.debug

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index e722e9d..e2cd7fb 100644 (file)
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -152,28 +152,33 @@ config DEBUG_SHIRQ
          Drivers ought to be able to handle interrupts coming in at those
          points; some don't and need to be caught.
 
-config DETECT_SOFTLOCKUP
-       bool "Detect Soft Lockups"
+config LOCKUP_DETECTOR
+       bool "Detect Hard and Soft Lockups"
        depends on DEBUG_KERNEL && !S390
-       default y
        help
-         Say Y here to enable the kernel to detect "soft lockups",
-         which are bugs that cause the kernel to loop in kernel
+         Say Y here to enable the kernel to act as a watchdog to detect
+         hard and soft lockups.
+
+         Softlockups are bugs that cause the kernel to loop in kernel
          mode for more than 60 seconds, without giving other tasks a
-         chance to run.
+         chance to run.  The current stack trace is displayed upon
+         detection and the system will stay locked up.
 
-         When a soft-lockup is detected, the kernel will print the
-         current stack trace (which you should report), but the
-         system will stay locked up. This feature has negligible
-         overhead.
+         Hardlockups are bugs that cause the CPU to loop in kernel mode
+         for more than 60 seconds, without letting other interrupts have a
+         chance to run.  The current stack trace is displayed upon detection
+         and the system will stay locked up.
+
+         The overhead should be minimal.  A periodic hrtimer runs to
+         generate interrupts and kick the watchdog task every 10-12 seconds.
+         An NMI is generated every 60 seconds or so to check for hardlockups.
 
-         (Note that "hard lockups" are separate type of bugs that
-          can be detected via the NMI-watchdog, on platforms that
-          support it.)
+config HARDLOCKUP_DETECTOR
+       def_bool LOCKUP_DETECTOR && PERF_EVENTS && HAVE_PERF_EVENTS_NMI
 
 config BOOTPARAM_SOFTLOCKUP_PANIC
        bool "Panic (Reboot) On Soft Lockups"
-       depends on DETECT_SOFTLOCKUP
+       depends on LOCKUP_DETECTOR
        help
          Say Y here to enable the kernel to panic on "soft lockups",
          which are bugs that cause the kernel to loop in kernel
@@ -190,7 +195,7 @@ config BOOTPARAM_SOFTLOCKUP_PANIC
 
 config BOOTPARAM_SOFTLOCKUP_PANIC_VALUE
        int
-       depends on DETECT_SOFTLOCKUP
+       depends on LOCKUP_DETECTOR
        range 0 1
        default 0 if !BOOTPARAM_SOFTLOCKUP_PANIC
        default 1 if BOOTPARAM_SOFTLOCKUP_PANIC