Merge tag 'trace-3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux...

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / kernel / trace / Kconfig

diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index fc382d6e2765d4a454a85aa5591c8edc452dccfb..5e9efd4b83a47fda4e70825078baabbc090a9a72 100644 (file)
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -176,6 +176,8 @@ config IRQSOFF_TRACER
        select GENERIC_TRACER
        select TRACER_MAX_TRACE
        select RING_BUFFER_ALLOW_SWAP
+       select TRACER_SNAPSHOT
+       select TRACER_SNAPSHOT_PER_CPU_SWAP
        help
          This option measures the time spent in irqs-off critical
          sections, with microsecond accuracy.
@@ -198,6 +200,8 @@ config PREEMPT_TRACER
        select GENERIC_TRACER
        select TRACER_MAX_TRACE
        select RING_BUFFER_ALLOW_SWAP
+       select TRACER_SNAPSHOT
+       select TRACER_SNAPSHOT_PER_CPU_SWAP
        help
          This option measures the time spent in preemption-off critical
          sections, with microsecond accuracy.
@@ -217,6 +221,7 @@ config SCHED_TRACER
        select GENERIC_TRACER
        select CONTEXT_SWITCH_TRACER
        select TRACER_MAX_TRACE
+       select TRACER_SNAPSHOT
        help
          This tracer tracks the latency of the highest priority task
          to be scheduled in, starting from the point it has woken up.
@@ -248,6 +253,27 @@ config TRACER_SNAPSHOT
              echo 1 > /sys/kernel/debug/tracing/snapshot
              cat snapshot
 
+config TRACER_SNAPSHOT_PER_CPU_SWAP
+        bool "Allow snapshot to swap per CPU"
+       depends on TRACER_SNAPSHOT
+       select RING_BUFFER_ALLOW_SWAP
+       help
+         Allow doing a snapshot of a single CPU buffer instead of a
+         full swap (all buffers). If this is set, then the following is
+         allowed:
+
+             echo 1 > /sys/kernel/debug/tracing/per_cpu/cpu2/snapshot
+
+         After which, only the tracing buffer for CPU 2 was swapped with
+         the main tracing buffer, and the other CPU buffers remain the same.
+
+         When this is enabled, this adds a little more overhead to the
+         trace recording, as it needs to add some checks to synchronize
+         recording with swaps. But this does not affect the performance
+         of the overall system. This is enabled by default when the preempt
+         or irq latency tracers are enabled, as those need to swap as well
+         and already adds the overhead (plus a lot more).
+
 config TRACE_BRANCH_PROFILING
        bool
        select GENERIC_TRACER
@@ -524,6 +550,29 @@ config RING_BUFFER_BENCHMARK
 
          If unsure, say N.
 
+config RING_BUFFER_STARTUP_TEST
+       bool "Ring buffer startup self test"
+       depends on RING_BUFFER
+       help
+         Run a simple self test on the ring buffer on boot up. Late in the
+        kernel boot sequence, the test will start that kicks off
+        a thread per cpu. Each thread will write various size events
+        into the ring buffer. Another thread is created to send IPIs
+        to each of the threads, where the IPI handler will also write
+        to the ring buffer, to test/stress the nesting ability.
+        If any anomalies are discovered, a warning will be displayed
+        and all ring buffers will be disabled.
+
+        The test runs for 10 seconds. This will slow your boot time
+        by at least 10 more seconds.
+
+        At the end of the test, statics and more checks are done.
+        It will output the stats of each per cpu buffer. What
+        was written, the sizes, what was read, what was lost, and
+        other similar details.
+
+        If unsure, say N
+
 endif # FTRACE
 
 endif # TRACING_SUPPORT