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@@ -12,17 +12,17 @@ config NOP_TRACER
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config HAVE_FTRACE_NMI_ENTER
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config HAVE_FTRACE_NMI_ENTER
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bool
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bool
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help
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help
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- See Documentation/trace/ftrace-implementation.txt
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+ See Documentation/trace/ftrace-design.txt
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config HAVE_FUNCTION_TRACER
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config HAVE_FUNCTION_TRACER
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bool
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bool
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help
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help
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- See Documentation/trace/ftrace-implementation.txt
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+ See Documentation/trace/ftrace-design.txt
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config HAVE_FUNCTION_GRAPH_TRACER
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config HAVE_FUNCTION_GRAPH_TRACER
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bool
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bool
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help
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help
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- See Documentation/trace/ftrace-implementation.txt
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+ See Documentation/trace/ftrace-design.txt
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config HAVE_FUNCTION_GRAPH_FP_TEST
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config HAVE_FUNCTION_GRAPH_FP_TEST
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bool
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bool
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@@ -34,17 +34,17 @@ config HAVE_FUNCTION_GRAPH_FP_TEST
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config HAVE_FUNCTION_TRACE_MCOUNT_TEST
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config HAVE_FUNCTION_TRACE_MCOUNT_TEST
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bool
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bool
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help
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help
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- See Documentation/trace/ftrace-implementation.txt
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+ See Documentation/trace/ftrace-design.txt
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config HAVE_DYNAMIC_FTRACE
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config HAVE_DYNAMIC_FTRACE
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bool
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bool
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help
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help
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- See Documentation/trace/ftrace-implementation.txt
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+ See Documentation/trace/ftrace-design.txt
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config HAVE_FTRACE_MCOUNT_RECORD
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config HAVE_FTRACE_MCOUNT_RECORD
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bool
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bool
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help
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help
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- See Documentation/trace/ftrace-implementation.txt
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+ See Documentation/trace/ftrace-design.txt
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config HAVE_HW_BRANCH_TRACER
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config HAVE_HW_BRANCH_TRACER
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bool
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bool
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@@ -52,7 +52,7 @@ config HAVE_HW_BRANCH_TRACER
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config HAVE_SYSCALL_TRACEPOINTS
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config HAVE_SYSCALL_TRACEPOINTS
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bool
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bool
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help
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help
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- See Documentation/trace/ftrace-implementation.txt
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+ See Documentation/trace/ftrace-design.txt
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config TRACER_MAX_TRACE
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config TRACER_MAX_TRACE
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bool
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bool
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@@ -83,7 +83,7 @@ config RING_BUFFER_ALLOW_SWAP
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# This allows those options to appear when no other tracer is selected. But the
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# This allows those options to appear when no other tracer is selected. But the
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# options do not appear when something else selects it. We need the two options
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# options do not appear when something else selects it. We need the two options
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# GENERIC_TRACER and TRACING to avoid circular dependencies to accomplish the
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# GENERIC_TRACER and TRACING to avoid circular dependencies to accomplish the
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-# hidding of the automatic options.
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+# hiding of the automatic options.
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config TRACING
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config TRACING
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bool
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bool
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@@ -119,7 +119,7 @@ menuconfig FTRACE
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bool "Tracers"
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bool "Tracers"
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default y if DEBUG_KERNEL
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default y if DEBUG_KERNEL
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help
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help
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- Enable the kernel tracing infrastructure.
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+ Enable the kernel tracing infrastructure.
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if FTRACE
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if FTRACE
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@@ -133,7 +133,7 @@ config FUNCTION_TRACER
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help
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help
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Enable the kernel to trace every kernel function. This is done
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Enable the kernel to trace every kernel function. This is done
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by using a compiler feature to insert a small, 5-byte No-Operation
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by using a compiler feature to insert a small, 5-byte No-Operation
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- instruction to the beginning of every kernel function, which NOP
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+ instruction at the beginning of every kernel function, which NOP
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sequence is then dynamically patched into a tracer call when
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sequence is then dynamically patched into a tracer call when
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tracing is enabled by the administrator. If it's runtime disabled
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tracing is enabled by the administrator. If it's runtime disabled
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(the bootup default), then the overhead of the instructions is very
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(the bootup default), then the overhead of the instructions is very
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@@ -150,7 +150,7 @@ config FUNCTION_GRAPH_TRACER
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and its entry.
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and its entry.
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Its first purpose is to trace the duration of functions and
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Its first purpose is to trace the duration of functions and
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draw a call graph for each thread with some information like
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draw a call graph for each thread with some information like
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- the return value. This is done by setting the current return
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+ the return value. This is done by setting the current return
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address on the current task structure into a stack of calls.
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address on the current task structure into a stack of calls.
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@@ -173,7 +173,7 @@ config IRQSOFF_TRACER
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echo 0 > /sys/kernel/debug/tracing/tracing_max_latency
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echo 0 > /sys/kernel/debug/tracing/tracing_max_latency
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- (Note that kernel size and overhead increases with this option
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+ (Note that kernel size and overhead increase with this option
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enabled. This option and the preempt-off timing option can be
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enabled. This option and the preempt-off timing option can be
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used together or separately.)
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used together or separately.)
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@@ -186,7 +186,7 @@ config PREEMPT_TRACER
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select TRACER_MAX_TRACE
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select TRACER_MAX_TRACE
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select RING_BUFFER_ALLOW_SWAP
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select RING_BUFFER_ALLOW_SWAP
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help
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help
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- This option measures the time spent in preemption off critical
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+ This option measures the time spent in preemption-off critical
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sections, with microsecond accuracy.
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sections, with microsecond accuracy.
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The default measurement method is a maximum search, which is
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The default measurement method is a maximum search, which is
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@@ -195,7 +195,7 @@ config PREEMPT_TRACER
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echo 0 > /sys/kernel/debug/tracing/tracing_max_latency
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echo 0 > /sys/kernel/debug/tracing/tracing_max_latency
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- (Note that kernel size and overhead increases with this option
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+ (Note that kernel size and overhead increase with this option
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enabled. This option and the irqs-off timing option can be
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enabled. This option and the irqs-off timing option can be
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used together or separately.)
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used together or separately.)
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@@ -222,7 +222,7 @@ config ENABLE_DEFAULT_TRACERS
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depends on !GENERIC_TRACER
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depends on !GENERIC_TRACER
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select TRACING
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select TRACING
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help
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help
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- This tracer hooks to various trace points in the kernel
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+ This tracer hooks to various trace points in the kernel,
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allowing the user to pick and choose which trace point they
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allowing the user to pick and choose which trace point they
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want to trace. It also includes the sched_switch tracer plugin.
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want to trace. It also includes the sched_switch tracer plugin.
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@@ -265,19 +265,19 @@ choice
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The likely/unlikely profiler only looks at the conditions that
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The likely/unlikely profiler only looks at the conditions that
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are annotated with a likely or unlikely macro.
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are annotated with a likely or unlikely macro.
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- The "all branch" profiler will profile every if statement in the
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+ The "all branch" profiler will profile every if-statement in the
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kernel. This profiler will also enable the likely/unlikely
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kernel. This profiler will also enable the likely/unlikely
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- profiler as well.
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+ profiler.
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- Either of the above profilers add a bit of overhead to the system.
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- If unsure choose "No branch profiling".
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+ Either of the above profilers adds a bit of overhead to the system.
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+ If unsure, choose "No branch profiling".
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config BRANCH_PROFILE_NONE
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config BRANCH_PROFILE_NONE
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bool "No branch profiling"
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bool "No branch profiling"
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help
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help
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- No branch profiling. Branch profiling adds a bit of overhead.
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- Only enable it if you want to analyse the branching behavior.
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- Otherwise keep it disabled.
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+ No branch profiling. Branch profiling adds a bit of overhead.
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+ Only enable it if you want to analyse the branching behavior.
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+ Otherwise keep it disabled.
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config PROFILE_ANNOTATED_BRANCHES
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config PROFILE_ANNOTATED_BRANCHES
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bool "Trace likely/unlikely profiler"
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bool "Trace likely/unlikely profiler"
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@@ -288,7 +288,7 @@ config PROFILE_ANNOTATED_BRANCHES
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/sys/kernel/debug/tracing/profile_annotated_branch
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/sys/kernel/debug/tracing/profile_annotated_branch
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- Note: this will add a significant overhead, only turn this
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+ Note: this will add a significant overhead; only turn this
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on if you need to profile the system's use of these macros.
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on if you need to profile the system's use of these macros.
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config PROFILE_ALL_BRANCHES
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config PROFILE_ALL_BRANCHES
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@@ -305,7 +305,7 @@ config PROFILE_ALL_BRANCHES
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This configuration, when enabled, will impose a great overhead
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This configuration, when enabled, will impose a great overhead
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on the system. This should only be enabled when the system
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on the system. This should only be enabled when the system
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- is to be analyzed
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+ is to be analyzed in much detail.
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endchoice
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endchoice
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config TRACING_BRANCHES
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config TRACING_BRANCHES
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@@ -335,7 +335,7 @@ config POWER_TRACER
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depends on X86
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depends on X86
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select GENERIC_TRACER
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select GENERIC_TRACER
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help
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help
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- This tracer helps developers to analyze and optimize the kernels
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+ This tracer helps developers to analyze and optimize the kernel's
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power management decisions, specifically the C-state and P-state
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power management decisions, specifically the C-state and P-state
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behavior.
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behavior.
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@@ -391,14 +391,14 @@ config HW_BRANCH_TRACER
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select GENERIC_TRACER
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select GENERIC_TRACER
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help
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help
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This tracer records all branches on the system in a circular
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This tracer records all branches on the system in a circular
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- buffer giving access to the last N branches for each cpu.
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+ buffer, giving access to the last N branches for each cpu.
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config KMEMTRACE
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config KMEMTRACE
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bool "Trace SLAB allocations"
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bool "Trace SLAB allocations"
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select GENERIC_TRACER
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select GENERIC_TRACER
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help
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help
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kmemtrace provides tracing for slab allocator functions, such as
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kmemtrace provides tracing for slab allocator functions, such as
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- kmalloc, kfree, kmem_cache_alloc, kmem_cache_free etc.. Collected
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+ kmalloc, kfree, kmem_cache_alloc, kmem_cache_free, etc. Collected
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data is then fed to the userspace application in order to analyse
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data is then fed to the userspace application in order to analyse
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allocation hotspots, internal fragmentation and so on, making it
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allocation hotspots, internal fragmentation and so on, making it
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possible to see how well an allocator performs, as well as debug
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possible to see how well an allocator performs, as well as debug
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@@ -417,15 +417,15 @@ config WORKQUEUE_TRACER
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bool "Trace workqueues"
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bool "Trace workqueues"
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select GENERIC_TRACER
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select GENERIC_TRACER
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help
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help
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- The workqueue tracer provides some statistical informations
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+ The workqueue tracer provides some statistical information
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about each cpu workqueue thread such as the number of the
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about each cpu workqueue thread such as the number of the
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works inserted and executed since their creation. It can help
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works inserted and executed since their creation. It can help
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- to evaluate the amount of work each of them have to perform.
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+ to evaluate the amount of work each of them has to perform.
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For example it can help a developer to decide whether he should
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For example it can help a developer to decide whether he should
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- choose a per cpu workqueue instead of a singlethreaded one.
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+ choose a per-cpu workqueue instead of a singlethreaded one.
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config BLK_DEV_IO_TRACE
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config BLK_DEV_IO_TRACE
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- bool "Support for tracing block io actions"
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+ bool "Support for tracing block IO actions"
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depends on SYSFS
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depends on SYSFS
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depends on BLOCK
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depends on BLOCK
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select RELAY
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select RELAY
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@@ -456,15 +456,15 @@ config KPROBE_EVENT
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select TRACING
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select TRACING
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default y
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default y
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help
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help
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- This allows the user to add tracing events (similar to tracepoints) on the fly
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- via the ftrace interface. See Documentation/trace/kprobetrace.txt
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- for more details.
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+ This allows the user to add tracing events (similar to tracepoints)
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+ on the fly via the ftrace interface. See
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+ Documentation/trace/kprobetrace.txt for more details.
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Those events can be inserted wherever kprobes can probe, and record
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Those events can be inserted wherever kprobes can probe, and record
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various register and memory values.
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various register and memory values.
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- This option is also required by perf-probe subcommand of perf tools. If
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- you want to use perf tools, this option is strongly recommended.
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+ This option is also required by perf-probe subcommand of perf tools.
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+ If you want to use perf tools, this option is strongly recommended.
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config DYNAMIC_FTRACE
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config DYNAMIC_FTRACE
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bool "enable/disable ftrace tracepoints dynamically"
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bool "enable/disable ftrace tracepoints dynamically"
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@@ -472,32 +472,32 @@ config DYNAMIC_FTRACE
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depends on HAVE_DYNAMIC_FTRACE
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depends on HAVE_DYNAMIC_FTRACE
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default y
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default y
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help
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help
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- This option will modify all the calls to ftrace dynamically
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- (will patch them out of the binary image and replaces them
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- with a No-Op instruction) as they are called. A table is
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- created to dynamically enable them again.
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+ This option will modify all the calls to ftrace dynamically
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+ (will patch them out of the binary image and replace them
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+ with a No-Op instruction) as they are called. A table is
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+ created to dynamically enable them again.
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- This way a CONFIG_FUNCTION_TRACER kernel is slightly larger, but otherwise
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- has native performance as long as no tracing is active.
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+ This way a CONFIG_FUNCTION_TRACER kernel is slightly larger, but
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+ otherwise has native performance as long as no tracing is active.
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- The changes to the code are done by a kernel thread that
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- wakes up once a second and checks to see if any ftrace calls
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- were made. If so, it runs stop_machine (stops all CPUS)
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- and modifies the code to jump over the call to ftrace.
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+ The changes to the code are done by a kernel thread that
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+ wakes up once a second and checks to see if any ftrace calls
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+ were made. If so, it runs stop_machine (stops all CPUS)
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+ and modifies the code to jump over the call to ftrace.
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config FUNCTION_PROFILER
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config FUNCTION_PROFILER
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bool "Kernel function profiler"
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bool "Kernel function profiler"
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depends on FUNCTION_TRACER
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depends on FUNCTION_TRACER
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default n
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default n
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help
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help
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- This option enables the kernel function profiler. A file is created
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- in debugfs called function_profile_enabled which defaults to zero.
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- When a 1 is echoed into this file profiling begins, and when a
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- zero is entered, profiling stops. A file in the trace_stats
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- directory called functions, that show the list of functions that
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- have been hit and their counters.
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+ This option enables the kernel function profiler. A file is created
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+ in debugfs called function_profile_enabled which defaults to zero.
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+ When a 1 is echoed into this file profiling begins, and when a
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+ zero is entered, profiling stops. A "functions" file is created in
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+ the trace_stats directory; this file shows the list of functions that
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+ have been hit and their counters.
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- If in doubt, say N
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+ If in doubt, say N.
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config FTRACE_MCOUNT_RECORD
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config FTRACE_MCOUNT_RECORD
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def_bool y
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def_bool y
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@@ -556,8 +556,8 @@ config RING_BUFFER_BENCHMARK
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tristate "Ring buffer benchmark stress tester"
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tristate "Ring buffer benchmark stress tester"
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depends on RING_BUFFER
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depends on RING_BUFFER
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help
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help
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- This option creates a test to stress the ring buffer and bench mark it.
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- It creates its own ring buffer such that it will not interfer with
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+ This option creates a test to stress the ring buffer and benchmark it.
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+ It creates its own ring buffer such that it will not interfere with
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any other users of the ring buffer (such as ftrace). It then creates
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any other users of the ring buffer (such as ftrace). It then creates
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a producer and consumer that will run for 10 seconds and sleep for
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a producer and consumer that will run for 10 seconds and sleep for
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10 seconds. Each interval it will print out the number of events
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10 seconds. Each interval it will print out the number of events
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@@ -566,7 +566,7 @@ config RING_BUFFER_BENCHMARK
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It does not disable interrupts or raise its priority, so it may be
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It does not disable interrupts or raise its priority, so it may be
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affected by processes that are running.
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affected by processes that are running.
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- If unsure, say N
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+ If unsure, say N.
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endif # FTRACE
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endif # FTRACE
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