- 07 Jul, 2011 1 commit>
- 18 May, 2011 7 commits
Since users of the function tracer can now pick and choose which functions they want to trace agnostically from other users of the function tracer, we need to pass the ops struct to the ftrace_set_filter() functions. The functions ftrace_set_global_filter() and ftrace_set_global_notrace() is added to keep the old filter functions which are used to modify the generic function tracers. Signed-off-by:
Steven Rostedt <rostedt@goodmis.org>
Now that functions may be selected individually, it only makes sense that we should allow dynamically allocated trace structures to be traced. This will allow perf to allocate a ftrace_ops structure at runtime and use it to pick and choose which functions that structure will trace. Note, a dynamically allocated ftrace_ops will always be called indirectly instead of being called directly from the mcount in entry.S. This is because there's no safe way to prevent mcount from being preempted before calling the function, unless we modify every entry.S to do so (not likely). Thus, dynamically allocated functions will now be called by the ftrace_ops_list_func() that loops through the ops that are allocated if there are more than one op allocated at a time. This loop is protected with a preempt_disable. To determine if an ftrace_ops structure is allocated or not, a new util function was added to the kernel/extable.c called core_kernel_data(), which returns 1 if the address is between _sdata and _edata. Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by:
Steven Rostedt <rostedt@goodmis.org>
ftrace_ops that are registered to trace functions can now be agnostic to each other in respect to what functions they trace. Each ops has their own hash of the functions they want to trace and a hash to what they do not want to trace. A empty hash for the functions they want to trace denotes all functions should be traced that are not in the notrace hash. Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by:
Steven Rostedt <rostedt@goodmis.org>
Every function has its own record that stores the instruction pointer and flags for the function to be traced. There are only two flags: enabled and free. The enabled flag states that tracing for the function has been enabled (actively traced), and the free flag states that the record no longer points to a function and can be used by new functions (loaded modules). These flags are now moved to the MSB of the flags (actually just the top 32bits). The rest of the bits (30 bits) are now used as a ref counter. Everytime a tracer register functions to trace, those functions will have its counter incremented. When tracing is enabled, to determine if a function should be traced, the counter is examined, and if it is non-zero it is set to trace. When a ftrace_ops is registered to trace functions, its hashes are examined. If the ftrace_ops filter_hash count is zero, then all functions are set to be traced, otherwise only the functions in the hash are to be traced. The exception to this is if a function is also in the ftrace_ops notrace_hash. Then that function's counter is not incremented for this ftrace_ops. Signed-off-by:
Steven Rostedt <rostedt@goodmis.org>
Combine the filter and notrace hashes to be accessed by a single entity, the global_ops. The global_ops is a ftrace_ops structure that is passed to different functions that can read or modify the filtering of the function tracer. The ftrace_ops structure was modified to hold a filter and notrace hashes so that later patches may allow each ftrace_ops to have its own set of rules to what functions may be filtered. Signed-off-by:
Steven Rostedt <rostedt@goodmis.org>
When multiple users are allowed to have their own set of functions to trace, having the FTRACE_FL_FILTER flag will not be enough to handle the accounting of those users. Each user will need their own set of functions. Replace the FTRACE_FL_FILTER with a filter_hash instead. This is temporary until the rest of the function filtering accounting gets in. Signed-off-by:
Steven Rostedt <rostedt@goodmis.org>
To prepare for the accounting system that will allow multiple users of the function tracer, having the FTRACE_FL_NOTRACE as a flag in the dyn_trace record does not make sense. All ftrace_ops will soon have a hash of functions they should trace and not trace. By making a global hash of functions not to trace makes this easier for the transition. Signed-off-by:
Steven Rostedt <rostedt@goodmis.org>
- 30 Apr, 2011 2 commits
Since we disable all function tracer processing if we detect that a modification of a instruction had failed, we do not need to track that the record has failed. No more ftrace processing is allowed, and the FTRACE_FL_CONVERTED flag is pointless. The FTRACE_FL_CONVERTED flag was used to denote records that were successfully converted from mcount calls into nops. But if a single record fails, all of ftrace is disabled. Signed-off-by:
Steven Rostedt <rostedt@goodmis.org>
Since we disable all function tracer processing if we detect that a modification of a instruction had failed, we do not need to track that the record has failed. No more ftrace processing is allowed, and the FTRACE_FL_FAILED flag is pointless. Removing this flag simplifies some of the code, but some ftrace_disabled checks needed to be added or move around a little. Signed-off-by:
Steven Rostedt <rostedt@goodmis.org>
- 11 Feb, 2011 1 commit
When the fuction graph tracer starts, it needs to make a special stack for each task to save the real return values of the tasks. All running tasks have this stack created, as well as any new tasks. On CPU hot plug, the new idle task will allocate a stack as well when init_idle() is called. The problem is that cpu hotplug does not create a new idle_task. Instead it uses the idle task that existed when the cpu went down. ftrace_graph_init_task() will add a new ret_stack to the task that is given to it. Because a clone will make the task have a stack of its parent it does not check if the task's ret_stack is already NULL or not. When the CPU hotplug code starts a CPU up again, it will allocate a new stack even though one already existed for it. The solution is to treat the idle_task specially. In fact, the function_graph code already does, just not at init_idle(). Instead of using the ftrace_graph_init_task() for the idle task, which that function expects the task to be a clone, have a separate ftrace_graph_init_idle_task(). Also, we will create a per_cpu ret_stack that is used by the idle task. When we call ftrace_graph_init_idle_task() it will check if the idle task's ret_stack is NULL, if it is, then it will assign it the per_cpu ret_stack. Reported-by:
Benjamin Herrenschmidt <benh@kernel.crashing.org> Suggested-by:
Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stable Tree <stable@kernel.org> Signed-off-by:
Steven Rostedt <rostedt@goodmis.org>
- 21 Jul, 2010 1 commit
- Mike Frysinger authored
Add more details to the dynamic function tracing design implementation. Signed-off-by:
Mike Frysinger <vapier@gentoo.org> LKML-Reference: <1279610015-10250-1-git-send-email-vapier@gentoo.org> Signed-off-by:
Steven Rostedt <rostedt@goodmis.org>
- 04 May, 2010 1 commit
The ftrace.h file contains several functions as macros when the functions are disabled due to config options. This patch converts most of them to static inlines. There are two exceptions: register_ftrace_function() and unregister_ftrace_function() This is because their parameter "ops" must not be evaluated since code using the function is allowed to #ifdef out the creation of the parameter. This also fixes an error caused by recent changes: kernel/trace/trace_irqsoff.c: In function 'start_irqsoff_tracer': kernel/trace/trace_irqsoff.c:571: error: expected expression before 'do' Reported-by:
Ingo Molnar <mingo@elte.hu> Signed-off-by:
Steven Rostedt <rostedt@goodmis.org>
- 27 Apr, 2010 1 commit
Add function graph output to irqsoff tracer. The graph output is enabled by setting new 'display-graph' trace option. Signed-off-by:
Jiri Olsa <jolsa@redhat.com> LKML-Reference: <1270227683-14631-4-git-send-email-jolsa@redhat.com> Signed-off-by:
Steven Rostedt <rostedt@goodmis.org>
- 21 Apr, 2010 1 commit
The ftrace_dump_on_oops kernel parameter, sysctl and sysrq let one dump every cpu buffers when an oops or panic happens. It's nice when you have few cpus but it may take ages if have many, plus you miss the real origin of the problem in all the cpu traces. Sometimes, all you need is to dump the cpu buffer that triggered the opps, most of the time it is our main interest. This patch modifies ftrace_dump_on_oops to handle this choice. The ftrace_dump_on_oops kernel parameter, when it comes alone, has the same behaviour than before. But ftrace_dump_on_oops=orig_cpu will only dump the buffer of the cpu that oops'ed. Similarly, sysctl kernel.ftrace_dump_on_oops=1 and echo 1 > /proc/sys/kernel/ftrace_dump_on_oops keep their previous behaviour. But setting 2 jumps into cpu origin dump mode. v2: Fix double setup v3: Fix spelling issues reported by Randy Dunlap v4: Also update __ftrace_dump in the selftests Signed-off-by:
Frederic Weisbecker <fweisbec@gmail.com> Acked-by:
David S. Miller <davem@davemloft.net> Acked-by:
Steven Rostedt <rostedt@goodmis.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
- 26 Mar, 2010 1 commit
- Peter Zijlstra authored>
- 17 Feb, 2010 1 commit
- Mike Frysinger authored
Most implementations of arch_syscall_addr() are the same, so create a default version in common code and move the one piece that differs (the syscall table) to asm/syscall.h. New arch ports don't have to waste time copying & pasting this simple function. The s390/sparc versions need to be different, so document why. Signed-off-by:
Mike Frysinger <vapier@gentoo.org> Acked-by:
David S. Miller <davem@davemloft.net> Acked-by:
Paul Mundt <lethal@linux-sh.org> Acked-by:
Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1264498803-17278-1-git-send-email-vapier@gentoo.org> Signed-off-by:
Frederic Weisbecker <fweisbec@gmail.com>
- 04 Feb, 2010 2 commits
- Masami Hiramatsu authored
Remove record freezing. Because kprobes never puts probe on ftrace's mcount call anymore, it doesn't need ftrace to check whether kprobes on it.> LKML-Reference: <20100202214925.4694.73469.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by:
Ingo Molnar <mingo@elte.hu>
- Masami Hiramatsu authored
Introducing *_text_reserved functions for checking the text address range is partially reserved or not. This patch provides checking routines for x86 smp alternatives and dynamic ftrace. Since both functions modify fixed pieces of kernel text, they should reserve and protect those from other dynamic text modifier, like kprobes. This will also be extended when introducing other subsystems which modify fixed pieces of kernel text. Dynamic text modifiers should avoid those.> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Mathieu Desnoyers <compudj@krystal.dyndns.org> Cc: Jason Baron <jbaron@redhat.com> LKML-Reference: <20100202214911.4694.16587.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by:
Ingo Molnar <mingo@elte.hu>
- 07 Oct, 2009 1 commit
- jolsa@redhat.com authored
When the module is about the unload we release its call records. The ftrace_release function was given wrong values representing the module core boundaries, thus not releasing its call records. Plus making ftrace_release function module specific. Signed-off-by:
Jiri Olsa <jolsa@redhat.com> LKML-Reference: <1254934835-363-3-git-send-email-jolsa@redhat.com> Cc: stable@kernel.org Signed-off-by:
Steven Rostedt <rostedt@goodmis.org>
- 24 Sep, 2009 1 commit
- Alexey Dobriyan authored>
- 20 Sep, 2009 1 commit
- Jaswinder Singh Rajput authored
fix the following 'make includecheck' warning: include/linux/ftrace.h: linux/sched.h is included more than once. Signed-off-by:
Jaswinder Singh Rajput <jaswinderrajput@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Sam Ravnborg <sam@ravnborg.org> LKML-Reference: <1247068321.4382.102.camel@ht.satnam>
- 18 Jun, 2009 1 commit>
- 17 Apr, 2009 2>
- 09 Apr, 2009 1 commit>
- 08 Apr, 2009 1 commit
- 1 commit
Impact: fix to crash going to kexec The init task did not properly initialize the function graph pointers. Altough these pointers are NULL, they can not be assumed to be NULL for the init task, and must still be properly initialize. This usually is not an issue since a problem only arises when a task exits, and the init tasks do not usually exit. But when doing tests with kexec, the init tasks do exit, and the bug appears. This patch properly initializes the init tasks function graph data structures. Reported-and-Tested-by:
Yinghai Lu <yinghai@kernel.org> LKML-Reference: <alpine.DEB.2.00.0903252053080.5675@gandalf.stny.rr.com> Signed-off-by:
Steven Rostedt <rostedt@goodmis.org> Signed-off-by:
Ingo Molnar <mingo@elte.hu>
- 25 Mar, 2009 3 commits
graph time is the time that a function is executing another function. Thus if function A calls B, if graph-time is set, then the time for A includes B. This is the default behavior. But if graph-time is off, then the time spent executing B is subtracted from A. Signed-off-by:
Steven Rostedt <srostedt@redhat.com>
Impact: reduce size of memory in function profiler The function profiler originally introduces its counters into the function records itself. There is 20 thousand different functions on a normal system, and that is adding 20 thousand counters for profiling event when not needed. A normal run of the profiler yields only a couple of thousand functions executed, depending on what is being profiled. This means we have around 18 thousand useless counters. This patch rectifies this by moving the data out of the function records used by dynamic ftrace. Data is preallocated to hold the functions when the profiling begins. Checks are made during profiling to see if more recorcds should be allocated, and they are allocated if it is safe to do so. This also removes the dependency from using dynamic ftrace, and also removes the overhead by having it enabled. Signed-off-by:
Steven Rostedt <srostedt@redhat.com>
Impact: new profiling feature. This feature depends on and uses dynamic function tracing. When the function profiling is disabled, no overhead occurs. But it still takes up around 300KB to hold the data, thus it is not recomended to keep it enabled for systems low on memory. When a '1' is echoed into the function_profile_enabled file, the counters for is function is reset back to zero. Thus you can see what functions are hit most by different programs. Signed-off-by:
Steven Rostedt <srostedt@redhat.com>
- 24 Mar, 2009 2 commits
Impact: cleanup struct dyn_ftrace::ip has different usages in his lifecycle, we use union for it. And also for struct dyn_ftrace::flags. Signed-off-by:
Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Steven Rostedt <srostedt@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <49C871BE.3080405@cn.fujitsu.com> Signed-off-by:
Ingo Molnar <mingo@elte.hu>
This patch move the timestamp from happening in the arch specific code into the general code. This allows for better control by the tracer to time manipulation. Signed-off-by:
Steven Rostedt <srostedt@redhat.com>
- 13 Mar, 2009 3 commits
Impact: new feature This adds the generic support for syscalls tracing. This is currently exploited through a devoted tracer but other tracing engines can use it. (They just have to play with {start,stop}_ftrace_syscalls() and use the display callbacks unless they want to override them.) The syscalls prototypes definitions are abused here to steal some metadata informations: - syscall name, param types, param names, number of params The syscall addr is not directly saved during this definition because we don't know if its prototype is available in the namespace. But we don't really need it. The arch has just to build a function able to resolve the syscall number to its metadata struct. The current tracer prints the syscall names, parameters names and values (and their types optionally). Currently the value is a raw hex but higher level values diplaying is on my TODO list. Signed-off-by:
Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <1236955332-10133-2-git-send-email-fweisbec@gmail.com> Signed-off-by:
Ingo Molnar <mingo@elte.hu>
Impact: save memory The struct dyn_ftrace table is very large, this patch will save about 50%. Signed-off-by:
Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Steven Rostedt <srostedt@redhat.com> LKML-Reference: <49BA2C9F.8020009@cn.fujitsu.com> Signed-off-by:
Ingo Molnar <mingo@elte.hu>
Provide basic callbacks to do syscall tracing. Signed-off-by:
Frederic Weisbecker <fweisbec@gmail.com> Acked-by:
Steven Rostedt <rostedt@goodmis.org> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> LKML-Reference: <1236401580-5758-2-git-send-email-fweisbec@gmail.com> [ simplified it to a trace_printk() for now. ] Signed-off-by:
Ingo Molnar <mingo@elte.hu>
- 06 Mar, 2009 3 commits:
Ingo Molnar <mingo@elte.hu>
Impact: add a generic printk() for tracing, like trace_printk() trace_bprintk() uses the infrastructure to record events on ring_buffer. [ fweisbec@gmail.com: ported to latest -tip, made it work if !CONFIG_MODULES, never free the format strings from modules because we can't keep track of them and conditionnaly create the ftrace format strings section -4-git-send-email-fweisbec@gmail.com> Signed-off-by:
Ingo Molnar <mingo@elte.hu>
Impact: save on memory for tracing Current tracers are typically using a struct(like struct ftrace_entry, struct ctx_switch_entry, struct special_entr etc...)to record a binary event. These structs can only record a their own kind of events. A new kind of tracer need a new struct and a lot of code too handle it. So we need a generic binary record for events. This infrastructure is for this purpose. [fweisbec@gmail.com: rebase against latest -tip, make it safe while sched tracing as-3-git-send-email-fweisbec@gmail.com> Signed-off-by:
Ingo Molnar <mingo@elte.hu>
- 05 Mar, 2009 1 commit> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Peter Zijlstra <peterz@infradead.org> LKML-Reference: <49af243d.06e9300a.53ad.ffff840c@mx.google.com> Signed-off-by:
Ingo Molnar <mingo@elte.hu>