diff options
Diffstat (limited to 'kernel/trace')
| -rw-r--r-- | kernel/trace/Kconfig | 142 |
1 files changed, 71 insertions, 71 deletions
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index 4484e783f68d..32fcbc00753b 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -172,6 +172,77 @@ config FUNCTION_GRAPH_TRACER the return value. This is done by setting the current return address on the current task structure into a stack of calls. +config DYNAMIC_FTRACE + bool "enable/disable function tracing dynamically" + depends on FUNCTION_TRACER + depends on HAVE_DYNAMIC_FTRACE + default y + help + This option will modify all the calls to function tracing + dynamically (will patch them out of the binary image and + replace them with a No-Op instruction) on boot up. During + compile time, a table is made of all the locations that ftrace + can function trace, and this table is linked into the kernel + image. When this is enabled, functions can be individually + enabled, and the functions not enabled will not affect + performance of the system. + + See the files in /sys/kernel/debug/tracing: + available_filter_functions + set_ftrace_filter + set_ftrace_notrace + + This way a CONFIG_FUNCTION_TRACER kernel is slightly larger, but + otherwise has native performance as long as no tracing is active. + +config DYNAMIC_FTRACE_WITH_REGS + def_bool y + depends on DYNAMIC_FTRACE + depends on HAVE_DYNAMIC_FTRACE_WITH_REGS + +config DYNAMIC_FTRACE_WITH_DIRECT_CALLS + def_bool y + depends on DYNAMIC_FTRACE + depends on HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS + +config FUNCTION_PROFILER + bool "Kernel function profiler" + depends on FUNCTION_TRACER + default n + help + This option enables the kernel function profiler. A file is created + in debugfs called function_profile_enabled which defaults to zero. + When a 1 is echoed into this file profiling begins, and when a + zero is entered, profiling stops. A "functions" file is created in + the trace_stat directory; this file shows the list of functions that + have been hit and their counters. + + If in doubt, say N. + +config STACK_TRACER + bool "Trace max stack" + depends on HAVE_FUNCTION_TRACER + select FUNCTION_TRACER + select STACKTRACE + select KALLSYMS + help + This special tracer records the maximum stack footprint of the + kernel and displays it in /sys/kernel/debug/tracing/stack_trace. + + This tracer works by hooking into every function call that the + kernel executes, and keeping a maximum stack depth value and + stack-trace saved. If this is configured with DYNAMIC_FTRACE + then it will not have any overhead while the stack tracer + is disabled. + + To enable the stack tracer on bootup, pass in 'stacktrace' + on the kernel command line. + + The stack tracer can also be enabled or disabled via the + sysctl kernel.stack_tracer_enabled + + Say N if unsure. + config TRACE_PREEMPT_TOGGLE bool help @@ -410,30 +481,6 @@ config BRANCH_TRACER Say N if unsure. -config STACK_TRACER - bool "Trace max stack" - depends on HAVE_FUNCTION_TRACER - select FUNCTION_TRACER - select STACKTRACE - select KALLSYMS - help - This special tracer records the maximum stack footprint of the - kernel and displays it in /sys/kernel/debug/tracing/stack_trace. - - This tracer works by hooking into every function call that the - kernel executes, and keeping a maximum stack depth value and - stack-trace saved. If this is configured with DYNAMIC_FTRACE - then it will not have any overhead while the stack tracer - is disabled. - - To enable the stack tracer on bootup, pass in 'stacktrace' - on the kernel command line. - - The stack tracer can also be enabled or disabled via the - sysctl kernel.stack_tracer_enabled - - Say N if unsure. - config BLK_DEV_IO_TRACE bool "Support for tracing block IO actions" depends on SYSFS @@ -531,53 +578,6 @@ config DYNAMIC_EVENTS config PROBE_EVENTS def_bool n -config DYNAMIC_FTRACE - bool "enable/disable function tracing dynamically" - depends on FUNCTION_TRACER - depends on HAVE_DYNAMIC_FTRACE - default y - help - This option will modify all the calls to function tracing - dynamically (will patch them out of the binary image and - replace them with a No-Op instruction) on boot up. During - compile time, a table is made of all the locations that ftrace - can function trace, and this table is linked into the kernel - image. When this is enabled, functions can be individually - enabled, and the functions not enabled will not affect - performance of the system. - - See the files in /sys/kernel/debug/tracing: - available_filter_functions - set_ftrace_filter - set_ftrace_notrace - - This way a CONFIG_FUNCTION_TRACER kernel is slightly larger, but - otherwise has native performance as long as no tracing is active. - -config DYNAMIC_FTRACE_WITH_REGS - def_bool y - depends on DYNAMIC_FTRACE - depends on HAVE_DYNAMIC_FTRACE_WITH_REGS - -config DYNAMIC_FTRACE_WITH_DIRECT_CALLS - def_bool y - depends on DYNAMIC_FTRACE - depends on HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS - -config FUNCTION_PROFILER - bool "Kernel function profiler" - depends on FUNCTION_TRACER - default n - help - This option enables the kernel function profiler. A file is created - in debugfs called function_profile_enabled which defaults to zero. - When a 1 is echoed into this file profiling begins, and when a - zero is entered, profiling stops. A "functions" file is created in - the trace_stat directory; this file shows the list of functions that - have been hit and their counters. - - If in doubt, say N. - config BPF_KPROBE_OVERRIDE bool "Enable BPF programs to override a kprobed function" depends on BPF_EVENTS |