linux/kernel/trace/Kconfig, branch v2.6.28

tracing, alpha: undefined reference to `save_stack_trace'

2008-11-03T09:12:13Z

Impact: build fix on !stacktrace architectures only select STACKTRACE on architectures that have STACKTRACE_SUPPORT ... since we also need to ifdef out the guts of ftrace_trace_stack(). We also want to disallow setting TRACE_ITER_STACKTRACE in trace_flags on such configs, but that can wait. Signed-off-by: Al Viro Acked-by: Steven Rostedt Signed-off-by: Ingo Molnar

ftrace: fix trace_nop config select

2008-10-29T16:21:05Z

Impact: build fix on non-function-tracing architectures The trace_nop is the tracer that is defined when no tracer is set in the ftrace infrastructure. The trace_nop was mistakenly selected by HAVE_FTRACE due to the confusion between ftrace infrastructure and the ftrace function tracer (which has been solved by renaming the function tracer). This patch changes the select to the approriate TRACING. This patch should fix compile errors on architectures that do not define the FUNCTION_TRACER. Signed-off-by: Steven Rostedt Signed-off-by: Ingo Molnar

tracing/ftrace: make boot tracer select the sched_switch tracer

2008-10-27T15:47:13Z

Impact: build fix If the boot tracer is selected but not the sched_switch, there will be a build failure: kernel/built-in.o: In function `boot_trace_init': trace_boot.c:(.text+0x5ee38): undefined reference to `sched_switch_trace' kernel/built-in.o: In function `disable_boot_trace': (.text+0x5eee1): undefined reference to `tracing_stop_cmdline_record' kernel/built-in.o: In function `enable_boot_trace': (.text+0x5ef11): undefined reference to `tracing_start_cmdline_record' This patch fixes it. Signed-off-by: Frederic Weisbecker Signed-off-by: Ingo Molnar

tracing: create tracers menu

2008-10-22T07:08:56Z

We seem to have plenty tracers, lets create a menu and not clutter the already cluttered debug menu more. Signed-off-by: Peter Zijlstra Acked-by: Frédéric Weisbecker Acked-by: Steven Rostedt Signed-off-by: Ingo Molnar

ftrace: rename FTRACE to FUNCTION_TRACER

2008-10-20T16:27:03Z

Due to confusion between the ftrace infrastructure and the gcc profiling tracer "ftrace", this patch renames the config options from FTRACE to FUNCTION_TRACER. The other two names that are offspring from FTRACE DYNAMIC_FTRACE and FTRACE_MCOUNT_RECORD will stay the same. This patch was generated mostly by script, and partially by hand. Signed-off-by: Steven Rostedt Signed-off-by: Ingo Molnar

ftrace: fix depends

2008-10-20T16:27:02Z

A lot of tracers have HAVE_FTRACE as a dependent config where it really should not. The HAVE_FTRACE is a misnomer (soon to be fixed) and describes if the architecture has the function tracer (mcount) implemented. The ftrace infrastructure is implemented in all archs. Signed-off-by: Steven Rostedt Signed-off-by: Ingo Molnar

tracing/fastboot: improve help text

2008-10-14T12:27:20Z

Improve the help text of the boot tracer. Signed-off-by: Ingo Molnar

tracing/stacktrace: improve help text

2008-10-14T12:15:43Z

Improve the help text that is displayed for CONFIG_STACK_TRACER. Signed-off-by: Ingo Molnar

tracing: unified trace buffer

2008-10-14T08:38:54Z

This is a unified tracing buffer that implements a ring buffer that hopefully everyone will eventually be able to use. The events recorded into the buffer have the following structure: struct ring_buffer_event { u32 type:2, len:3, time_delta:27; u32 array[]; }; The minimum size of an event is 8 bytes. All events are 4 byte aligned inside the buffer. There are 4 types (all internal use for the ring buffer, only the data type is exported to the interface users). RINGBUF_TYPE_PADDING: this type is used to note extra space at the end of a buffer page. RINGBUF_TYPE_TIME_EXTENT: This type is used when the time between events is greater than the 27 bit delta can hold. We add another 32 bits, and record that in its own event (8 byte size). RINGBUF_TYPE_TIME_STAMP: (Not implemented yet). This will hold data to help keep the buffer timestamps in sync. RINGBUF_TYPE_DATA: The event actually holds user data. The "len" field is only three bits. Since the data must be 4 byte aligned, this field is shifted left by 2, giving a max length of 28 bytes. If the data load is greater than 28 bytes, the first array field holds the full length of the data load and the len field is set to zero. Example, data size of 7 bytes: type = RINGBUF_TYPE_DATA len = 2 time_delta: - array[0..1]: <7 bytes of data> <1 byte empty> This event is saved in 12 bytes of the buffer. An event with 82 bytes of data: type = RINGBUF_TYPE_DATA len = 0 time_delta: - array[0]: 84 (Note the alignment) array[1..14]: <82 bytes of data> <2 bytes empty> The above event is saved in 92 bytes (if my math is correct). 82 bytes of data, 2 bytes empty, 4 byte header, 4 byte length. Do not reference the above event struct directly. Use the following functions to gain access to the event table, since the ring_buffer_event structure may change in the future. ring_buffer_event_length(event): get the length of the event. This is the size of the memory used to record this event, and not the size of the data pay load. ring_buffer_time_delta(event): get the time delta of the event This returns the delta time stamp since the last event. Note: Even though this is in the header, there should be no reason to access this directly, accept for debugging. ring_buffer_event_data(event): get the data from the event This is the function to use to get the actual data from the event. Note, it is only a pointer to the data inside the buffer. This data must be copied to another location otherwise you risk it being written over in the buffer. ring_buffer_lock: A way to lock the entire buffer. ring_buffer_unlock: unlock the buffer. ring_buffer_alloc: create a new ring buffer. Can choose between overwrite or consumer/producer mode. Overwrite will overwrite old data, where as consumer producer will throw away new data if the consumer catches up with the producer. The consumer/producer is the default. ring_buffer_free: free the ring buffer. ring_buffer_resize: resize the buffer. Changes the size of each cpu buffer. Note, it is up to the caller to provide that the buffer is not being used while this is happening. This requirement may go away but do not count on it. ring_buffer_lock_reserve: locks the ring buffer and allocates an entry on the buffer to write to. ring_buffer_unlock_commit: unlocks the ring buffer and commits it to the buffer. ring_buffer_write: writes some data into the ring buffer. ring_buffer_peek: Look at a next item in the cpu buffer. ring_buffer_consume: get the next item in the cpu buffer and consume it. That is, this function increments the head pointer. ring_buffer_read_start: Start an iterator of a cpu buffer. For now, this disables the cpu buffer, until you issue a finish. This is just because we do not want the iterator to be overwritten. This restriction may change in the future. But note, this is used for static reading of a buffer which is usually done "after" a trace. Live readings would want to use the ring_buffer_consume above, which will not disable the ring buffer. ring_buffer_read_finish: Finishes the read iterator and reenables the ring buffer. ring_buffer_iter_peek: Look at the next item in the cpu iterator. ring_buffer_read: Read the iterator and increment it. ring_buffer_iter_reset: Reset the iterator to point to the beginning of the cpu buffer. ring_buffer_iter_empty: Returns true if the iterator is at the end of the cpu buffer. ring_buffer_size: returns the size in bytes of each cpu buffer. Note, the real size is this times the number of CPUs. ring_buffer_reset_cpu: Sets the cpu buffer to empty ring_buffer_reset: sets all cpu buffers to empty ring_buffer_swap_cpu: swaps a cpu buffer from one buffer with a cpu buffer of another buffer. This is handy when you want to take a snap shot of a running trace on just one cpu. Having a backup buffer, to swap with facilitates this. Ftrace max latencies use this. ring_buffer_empty: Returns true if the ring buffer is empty. ring_buffer_empty_cpu: Returns true if the cpu buffer is empty. ring_buffer_record_disable: disable all cpu buffers (read only) ring_buffer_record_disable_cpu: disable a single cpu buffer (read only) ring_buffer_record_enable: enable all cpu buffers. ring_buffer_record_enabl_cpu: enable a single cpu buffer. ring_buffer_entries: The number of entries in a ring buffer. ring_buffer_overruns: The number of entries removed due to writing wrap. ring_buffer_time_stamp: Get the time stamp used by the ring buffer ring_buffer_normalize_time_stamp: normalize the ring buffer time stamp into nanosecs. I still need to implement the GTOD feature. But we need support from the cpu frequency infrastructure. But this can be done at a later time without affecting the ring buffer interface. Signed-off-by: Steven Rostedt Signed-off-by: Ingo Molnar

ftrace/fastboot: disable tracers self-tests when boot tracer is selected

2008-10-14T08:38:51Z

The tracing engine resets the ring buffer and the tracers touch it too during self-tests. These self-tests happen during tracers registering and work against boot tracing which is logging initcalls. We have to disable tracing self-tests if the boot-tracer is selected. Reported-by: Ingo Molnar Signed-off-by: Frederic Weisbecker Signed-off-by: Ingo Molnar