kernel/include/trace/ftrace.h, branch linux-3.11.y

tracing/perf: Move the PERF_MAX_TRACE_SIZE check into perf_trace_buf_prepare()

2013-07-19T01:31:28Z

Every perf_trace_buf_prepare() caller does WARN_ONCE(size > PERF_MAX_TRACE_SIZE, message) and "message" is almost the same. Shift this WARN_ONCE() into perf_trace_buf_prepare(). This changes the meaning of _ONCE, but I think this is fine. - 4947014 2932448 10104832 17984294 1126b26 vmlinux + 4948422 2932448 10104832 17985702 11270a6 vmlinux on my build. Link: http://lkml.kernel.org/r/20130617170211.GA19813@redhat.com Acked-by: Peter Zijlstra Signed-off-by: Oleg Nesterov Signed-off-by: Steven Rostedt

tracing: Add DEFINE_EVENT_FN() macro

2013-06-21T05:24:32Z

Each TRACE_EVENT() adds several helper functions. If two or more trace events share the same structure and print format, they can also share most of these helper functions and save a lot of space from duplicate code. This is why the DECLARE_EVENT_CLASS() and DEFINE_EVENT() were created. Some events require a trigger to be called at registering and unregistering of the event and to do so they use TRACE_EVENT_FN(). If multiple events require a trigger, they currently have no choice but to use TRACE_EVENT_FN() as there's no DEFINE_EVENT_FN() available. This unfortunately causes a lot of wasted duplicate code created. By adding a DEFINE_EVENT_FN(), these events can still use a DECLARE_EVENT_CLASS() and then define their own triggers. Signed-off-by: Steven Rostedt Link: http://lkml.kernel.org/r/51C3236C.8030508@hds.com Signed-off-by: Seiji Aguchi Signed-off-by: H. Peter Anvin

tracing: Remove obsolete macro guard _TRACE_PROFILE_INIT

2013-04-13T03:02:33Z

The macro _TRACE_PROFILE_INIT was removed a long time ago, but an "#undef" guard was left behind. Remove it. Link: http://lkml.kernel.org/r/514684EE.6000805@huawei.com Signed-off-by: zhangwei(Jovi) Signed-off-by: Steven Rostedt

tracing: Add a way to soft disable trace events

2013-03-15T04:36:03Z

In order to let triggers enable or disable events, we need a 'soft' method for doing so. For example, if a function probe is added that lets a user enable or disable events when a function is called, that change must be done without taking locks or a mutex, and definitely it can't sleep. But the full enabling of a tracepoint is expensive. By adding a 'SOFT_DISABLE' flag, and converting the flags to be updated without the protection of a mutex (using set/clear_bit()), this soft disable flag can be used to allow critical sections to enable or disable events from being traced (after the event has been placed into "SOFT_MODE"). Some caveats though: The comm recorder (to map pids with a comm) can not be soft disabled (yet). If you disable an event with with a "soft" disable and wait a while before reading the trace, the comm cache may be replaced and you'll get a bunch of <...> for comms in the trace. Reading the "enable" file for an event that is disabled will now give you "0*" where the '*' denotes that the tracepoint is still active but the event itself is "disabled". [ fixed _BIT used in & operation : thanks to Dan Carpenter and smatch ] Cc: Dan Carpenter Cc: Tom Zanussi Signed-off-by: Steven Rostedt

tracing: Fix some section mismatch warnings

2013-03-15T04:34:54Z

As we've added __init annotation to field-defining functions, we should add __refdata annotation to event_call variables, which reference those functions. Link: http://lkml.kernel.org/r/51343C1F.2050502@huawei.com Reported-by: Fengguang Wu Signed-off-by: Li Zefan Signed-off-by: Steven Rostedt

tracing: Annotate event field-defining functions with __init

2013-03-15T04:34:51Z

Those functions are called either during kernel boot or module init. Before: $ dmesg | grep 'Freeing unused kernel memory' Freeing unused kernel memory: 1208k freed Freeing unused kernel memory: 1360k freed Freeing unused kernel memory: 1960k freed After: $ dmesg | grep 'Freeing unused kernel memory' Freeing unused kernel memory: 1236k freed Freeing unused kernel memory: 1388k freed Freeing unused kernel memory: 1960k freed Link: http://lkml.kernel.org/r/5125877D.5000201@huawei.com Signed-off-by: Li Zefan Signed-off-by: Steven Rostedt

tracing: Add a helper function for event print functions

2013-03-15T04:34:51Z

Move duplicate code in event print functions to a helper function. This shrinks the size of the kernel by ~13K. text data bss dec hex filename 6596137 1743966 10138672 18478775 119f6b7 vmlinux.o.old 6583002 1743849 10138672 18465523 119c2f3 vmlinux.o.new Link: http://lkml.kernel.org/r/51258746.2060304@huawei.com Signed-off-by: Li Zefan Signed-off-by: Steven Rostedt

tracing: Pass the ftrace_file to the buffer lock reserve code

2013-03-15T04:34:42Z

Pass the struct ftrace_event_file *ftrace_file to the trace_event_buffer_lock_reserve() (new function that replaces the trace_current_buffer_lock_reserver()). The ftrace_file holds a pointer to the trace_array that is in use. In the case of multiple buffers with different trace_arrays, this allows different events to be recorded into different buffers. Also fixed some of the stale comments in include/trace/ftrace.h Signed-off-by: Steven Rostedt

tracing: Separate out trace events from global variables

2013-03-15T04:34:40Z

The trace events for ftrace are all defined via global variables. The arrays of events and event systems are linked to a global list. This prevents multiple users of the event system (what to enable and what not to). By adding descriptors to represent the event/file relation, as well as to which trace_array descriptor they are associated with, allows for more than one set of events to be defined. Once the trace events files have a link between the trace event and the trace_array they are associated with, we can create multiple trace_arrays that can record separate events in separate buffers. Signed-off-by: Steven Rostedt

tracing: Kill unused and puzzled sample code in ftrace.h

2012-11-13T20:51:21Z

When doing per-cpu helper optimizing work, find that this code is so puzzled. 1. It's mark as comment text, maybe a sample function for guidelines or a todo work. 2. But, this sample code is odd where struct perf_trace_buf is nonexistent. commit ce71b9 delete struct perf_trace_buf definition. Author: Frederic Weisbecker Date: Sun Nov 22 05:26:55 2009 +0100 tracing: Use the perf recursion protection from trace event Is it necessary to keep there? just compile test. Link: http://lkml.kernel.org/r/50949FC9.6050202@gmail.com Signed-off-by: Shan Wei Signed-off-by: Steven Rostedt