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2016-04-07perf: split perf_trace_buf_prepare into alloc and update partsAlexei Starovoitov
split allows to move expensive update of 'struct trace_entry' to later phase. Repurpose unused 1st argument of perf_tp_event() to indicate event type. While splitting use temp variable 'rctx' instead of '*rctx' to avoid unnecessary loads done by the compiler due to -fno-strict-aliasing Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-24Merge tag 'trace-v4.6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "Nothing major this round. Mostly small clean ups and fixes. Some visible changes: - A new flag was added to distinguish traces done in NMI context. - Preempt tracer now shows functions where preemption is disabled but interrupts are still enabled. Other notes: - Updates were done to function tracing to allow better performance with perf. - Infrastructure code has been added to allow for a new histogram feature for recording live trace event histograms that can be configured by simple user commands. The feature itself was just finished, but needs a round in linux-next before being pulled. This only includes some infrastructure changes that will be needed" * tag 'trace-v4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (22 commits) tracing: Record and show NMI state tracing: Fix trace_printk() to print when not using bprintk() tracing: Remove redundant reset per-CPU buff in irqsoff tracer x86: ftrace: Fix the misleading comment for arch/x86/kernel/ftrace.c tracing: Fix crash from reading trace_pipe with sendfile tracing: Have preempt(irqs)off trace preempt disabled functions tracing: Fix return while holding a lock in register_tracer() ftrace: Use kasprintf() in ftrace_profile_tracefs() ftrace: Update dynamic ftrace calls only if necessary ftrace: Make ftrace_hash_rec_enable return update bool tracing: Fix typoes in code comment and printk in trace_nop.c tracing, writeback: Replace cgroup path to cgroup ino tracing: Use flags instead of bool in trigger structure tracing: Add an unreg_all() callback to trigger commands tracing: Add needs_rec flag to event triggers tracing: Add a per-event-trigger 'paused' field tracing: Add get_syscall_name() tracing: Add event record param to trigger_ops.func() tracing: Make event trigger functions available tracing: Make ftrace_event_field checking functions available ...
2016-03-08tracing: Add get_syscall_name()Tom Zanussi
Add a utility function to grab the syscall name from the syscall metadata, given a syscall id. Link: http://lkml.kernel.org/r/be26a8dfe3f15e16a837799f1c1e2b4d62742843.1449767187.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Tested-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Reviewed-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-02-29tracing/syscalls: Rename "/format" tracepoint field name "nr" to "__syscall_nr:Taeung Song
Some tracepoint have multiple fields with the same name, "nr", the first one is a unique syscall ID, the other is a syscall argument: # cat /sys/kernel/debug/tracing/events/syscalls/sys_enter_io_getevents/format name: sys_enter_io_getevents ID: 747 format: field:unsigned short common_type; offset:0; size:2; signed:0; field:unsigned char common_flags; offset:2; size:1; signed:0; field:unsigned char common_preempt_count; offset:3; size:1; signed:0; field:int common_pid; offset:4; size:4; signed:1; field:int nr; offset:8; size:4; signed:1; field:aio_context_t ctx_id; offset:16; size:8; signed:0; field:long min_nr; offset:24; size:8; signed:0; field:long nr; offset:32; size:8; signed:0; field:struct io_event * events; offset:40; size:8; signed:0; field:struct timespec * timeout; offset:48; size:8; signed:0; print fmt: "ctx_id: 0x%08lx, min_nr: 0x%08lx, nr: 0x%08lx, events: 0x%08lx, timeout: 0x%08lx", ((unsigned long)(REC->ctx_id)), ((unsigned long)(REC->min_nr)), ((unsigned long)(REC->nr)), ((unsigned long)(REC->events)), ((unsigned long)(REC->timeout)) # Fix it by renaming the "/format" common tracepoint field "nr" to "__syscall_nr". Signed-off-by: Taeung Song <treeze.taeung@gmail.com> [ Do not rename the struct member, just the '/format' field name ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Lai Jiangshan <jiangshanlai@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160226132301.3ae065a4@gandalf.local.home Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-09-30tracing: Move trace_flags from global to a trace_array fieldSteven Rostedt (Red Hat)
In preparation to make trace options per instance, the global trace_flags needs to be moved from being a global variable to a field within the trace instance trace_array structure. There's still more work to do, as there's some functions that use trace_flags without passing in a way to get to the current_trace array. For those, the global_trace is used directly (from trace.c). This includes setting and clearing the trace_flags. This means that when a new instance is created, it just gets the trace_flags of the global_trace and will not be able to modify them. Depending on the functions that have access to the trace_array, the flags of an instance may not affect parts of its trace, where the global_trace is used. These will be fixed in future changes. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-05-13tracing: Rename ftrace_trigger_soft_disabled() to trace_trigger_soft_disabled()Steven Rostedt (Red Hat)
The name "ftrace" really refers to the function hook infrastructure. It is not about the trace_events. The ftrace_trigger_soft_disabled() tests if a trace_event is soft disabled (called but not traced), and returns true if it is. It has nothing to do with function tracing and should be renamed. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-05-13tracing: Rename ftrace_event_{call,class} to trace_event_{call,class}Steven Rostedt (Red Hat)
The name "ftrace" really refers to the function hook infrastructure. It is not about the trace_events. The structures ftrace_event_call and ftrace_event_class have nothing to do with the function hooks, and are really trace_event structures. Rename ftrace_event_* to trace_event_*. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-05-13tracing: Rename ftrace_event_file to trace_event_fileSteven Rostedt (Red Hat)
The name "ftrace" really refers to the function hook infrastructure. It is not about the trace_events. The structure ftrace_event_file is really about trace events and not "ftrace". Rename it to trace_event_file. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2015-01-14perf: Avoid horrible stack usagePeter Zijlstra (Intel)
Both Linus (most recent) and Steve (a while ago) reported that perf related callbacks have massive stack bloat. The problem is that software events need a pt_regs in order to properly report the event location and unwind stack. And because we could not assume one was present we allocated one on stack and filled it with minimal bits required for operation. Now, pt_regs is quite large, so this is undesirable. Furthermore it turns out that most sites actually have a pt_regs pointer available, making this even more onerous, as the stack space is pointless waste. This patch addresses the problem by observing that software events have well defined nesting semantics, therefore we can use static per-cpu storage instead of on-stack. Linus made the further observation that all but the scheduler callers of perf_sw_event() have a pt_regs available, so we change the regular perf_sw_event() to require a valid pt_regs (where it used to be optional) and add perf_sw_event_sched() for the scheduler. We have a scheduler specific call instead of a more generic _noregs() like construct because we can assume non-recursion from the scheduler and thereby simplify the code further (_noregs would have to put the recursion context call inline in order to assertain which __perf_regs element to use). One last note on the implementation of perf_trace_buf_prepare(); we allow .regs = NULL for those cases where we already have a pt_regs pointer available and do not need another. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Reported-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Javi Merino <javi.merino@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Petr Mladek <pmladek@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tom.zanussi@linux.intel.com> Cc: Vaibhav Nagarnaik <vnagarnaik@google.com> Link: http://lkml.kernel.org/r/20141216115041.GW3337@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-12-16Merge tag 'trace-3.19-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "As the merge window is still open, and this code was not as complex as I thought it might be. I'm pushing this in now. This will allow Thomas to debug his irq work for 3.20. This adds two new features: 1) Allow traceopoints to be enabled right after mm_init(). By passing in the trace_event= kernel command line parameter, tracepoints can be enabled at boot up. For debugging things like the initialization of interrupts, it is needed to have tracepoints enabled very early. People have asked about this before and this has been on my todo list. As it can be helpful for Thomas to debug his upcoming 3.20 IRQ work, I'm pushing this now. This way he can add tracepoints into the IRQ set up and have users enable them when things go wrong. 2) Have the tracepoints printed via printk() (the console) when they are triggered. If the irq code locks up or reboots the box, having the tracepoint output go into the kernel ring buffer is useless for debugging. But being able to add the tp_printk kernel command line option along with the trace_event= option will have these tracepoints printed as they occur, and that can be really useful for debugging early lock up or reboot problems. This code is not that intrusive and it passed all my tests. Thomas tried them out too and it works for his needs. Link: http://lkml.kernel.org/r/20141214201609.126831471@goodmis.org" * tag 'trace-3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Add tp_printk cmdline to have tracepoints go to printk() tracing: Move enabling tracepoints to just after rcu_init()
2014-12-15tracing: Move enabling tracepoints to just after rcu_init()Steven Rostedt (Red Hat)
Enabling tracepoints at boot up can be very useful. The tracepoint can be initialized right after RCU has been. There's no need to wait for the early_initcall() to be called. That's too late for some things that can use tracepoints for debugging. Move the logic to enable tracepoints out of the initcalls and into init/main.c to right after rcu_init(). This also allows trace_printk() to be used early too. Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1412121539300.16494@nanos Link: http://lkml.kernel.org/r/20141214164104.307127356@goodmis.org Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Suggested-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-12-10Merge tag 'trace-3.19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "There was a lot of clean ups and minor fixes. One of those clean ups was to the trace_seq code. It also removed the return values to the trace_seq_*() functions and use trace_seq_has_overflowed() to see if the buffer filled up or not. This is similar to work being done to the seq_file code as well in another tree. Some of the other goodies include: - Added some "!" (NOT) logic to the tracing filter. - Fixed the frame pointer logic to the x86_64 mcount trampolines - Added the logic for dynamic trampolines on !CONFIG_PREEMPT systems. That is, the ftrace trampoline can be dynamically allocated and be called directly by functions that only have a single hook to them" * tag 'trace-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (55 commits) tracing: Truncated output is better than nothing tracing: Add additional marks to signal very large time deltas Documentation: describe trace_buf_size parameter more accurately tracing: Allow NOT to filter AND and OR clauses tracing: Add NOT to filtering logic ftrace/fgraph/x86: Have prepare_ftrace_return() take ip as first parameter ftrace/x86: Get rid of ftrace_caller_setup ftrace/x86: Have save_mcount_regs macro also save stack frames if needed ftrace/x86: Add macro MCOUNT_REG_SIZE for amount of stack used to save mcount regs ftrace/x86: Simplify save_mcount_regs on getting RIP ftrace/x86: Have save_mcount_regs store RIP in %rdi for first parameter ftrace/x86: Rename MCOUNT_SAVE_FRAME and add more detailed comments ftrace/x86: Move MCOUNT_SAVE_FRAME out of header file ftrace/x86: Have static tracing also use ftrace_caller_setup ftrace/x86: Have static function tracing always test for function graph kprobes: Add IPMODIFY flag to kprobe_ftrace_ops ftrace, kprobes: Support IPMODIFY flag to find IP modify conflict kprobes/ftrace: Recover original IP if pre_handler doesn't change it tracing/trivial: Fix typos and make an int into a bool tracing: Deletion of an unnecessary check before iput() ...
2014-11-19tracing: Do not use return values of trace_seq_printf() in syscall tracingSteven Rostedt (Red Hat)
The functions trace_seq_printf() and friends will not be returning values soon and will be void functions. To know if they succeeded or not, the functions trace_seq_has_overflowed() and trace_handle_return() should be used instead. Reviewed-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-10-30tracing/syscalls: Ignore numbers outside NR_syscalls' rangeRabin Vincent
ARM has some private syscalls (for example, set_tls(2)) which lie outside the range of NR_syscalls. If any of these are called while syscall tracing is being performed, out-of-bounds array access will occur in the ftrace and perf sys_{enter,exit} handlers. # trace-cmd record -e raw_syscalls:* true && trace-cmd report ... true-653 [000] 384.675777: sys_enter: NR 192 (0, 1000, 3, 4000022, ffffffff, 0) true-653 [000] 384.675812: sys_exit: NR 192 = 1995915264 true-653 [000] 384.675971: sys_enter: NR 983045 (76f74480, 76f74000, 76f74b28, 76f74480, 76f76f74, 1) true-653 [000] 384.675988: sys_exit: NR 983045 = 0 ... # trace-cmd record -e syscalls:* true [ 17.289329] Unable to handle kernel paging request at virtual address aaaaaace [ 17.289590] pgd = 9e71c000 [ 17.289696] [aaaaaace] *pgd=00000000 [ 17.289985] Internal error: Oops: 5 [#1] PREEMPT SMP ARM [ 17.290169] Modules linked in: [ 17.290391] CPU: 0 PID: 704 Comm: true Not tainted 3.18.0-rc2+ #21 [ 17.290585] task: 9f4dab00 ti: 9e710000 task.ti: 9e710000 [ 17.290747] PC is at ftrace_syscall_enter+0x48/0x1f8 [ 17.290866] LR is at syscall_trace_enter+0x124/0x184 Fix this by ignoring out-of-NR_syscalls-bounds syscall numbers. Commit cd0980fc8add "tracing: Check invalid syscall nr while tracing syscalls" added the check for less than zero, but it should have also checked for greater than NR_syscalls. Link: http://lkml.kernel.org/p/1414620418-29472-1-git-send-email-rabin@rab.in Fixes: cd0980fc8add "tracing: Check invalid syscall nr while tracing syscalls" Cc: stable@vger.kernel.org # 2.6.33+ Signed-off-by: Rabin Vincent <rabin@rab.in> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-09-10kernel: trace_syscalls: Replace rcu_assign_pointer() with RCU_INIT_POINTER()Andreea-Cristina Bernat
The uses of "rcu_assign_pointer()" are NULLing out the pointers. According to RCU_INIT_POINTER()'s block comment: "1. This use of RCU_INIT_POINTER() is NULLing out the pointer" it is better to use it instead of rcu_assign_pointer() because it has a smaller overhead. The following Coccinelle semantic patch was used: @@ @@ - rcu_assign_pointer + RCU_INIT_POINTER (..., NULL) Link: http://lkml.kernel.org/p/20140822142822.GA32391@ada Signed-off-by: Andreea-Cristina Bernat <bernat.ada@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-01-09tracing: Consolidate event trigger codeSteven Rostedt (Red Hat)
The event trigger code that checks for callback triggers before and after recording of an event has lots of flags checks. This code is duplicated throughout the ftrace events, kprobes and system calls. They all do the exact same checks against the event flags. Added helper functions ftrace_trigger_soft_disabled(), event_trigger_unlock_commit() and event_trigger_unlock_commit_regs() that consolidated the code and these are used instead. Link: http://lkml.kernel.org/r/20140106222703.5e7dbba2@gandalf.local.home Acked-by: Tom Zanussi <tom.zanussi@linux.intel.com> Tested-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-01-06tracing: Remove double-underscore naming in syscall trigger invocationsTom Zanussi
There's no reason to use double-underscores for any variable name in ftrace_syscall_enter()/exit(), since those functions aren't generated and there's no need to avoid namespace collisions as with the event macros, which is where the original invocation code came from. Link: http://lkml.kernel.org/r/0b489c9d1f7ee315cff60fa0e4c2b433ade8ae0d.1389036657.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-12-21tracing: Add and use generic set_trigger_filter() implementationTom Zanussi
Add a generic event_command.set_trigger_filter() op implementation and have the current set of trigger commands use it - this essentially gives them all support for filters. Syntactically, filters are supported by adding 'if <filter>' just after the command, in which case only events matching the filter will invoke the trigger. For example, to add a filter to an enable/disable_event command: echo 'enable_event:system:event if common_pid == 999' > \ .../othersys/otherevent/trigger The above command will only enable the system:event event if the common_pid field in the othersys:otherevent event is 999. As another example, to add a filter to a stacktrace command: echo 'stacktrace if common_pid == 999' > \ .../somesys/someevent/trigger The above command will only trigger a stacktrace if the common_pid field in the event is 999. The filter syntax is the same as that described in the 'Event filtering' section of Documentation/trace/events.txt. Because triggers can now use filters, the trigger-invoking logic needs to be moved in those cases - e.g. for ftrace_raw_event_calls, if a trigger has a filter associated with it, the trigger invocation now needs to happen after the { assign; } part of the call, in order for the trigger condition to be tested. There's still a SOFT_DISABLED-only check at the top of e.g. the ftrace_raw_events function, so when an event is soft disabled but not because of the presence of a trigger, the original SOFT_DISABLED behavior remains unchanged. There's also a bit of trickiness in that some triggers need to avoid being invoked while an event is currently in the process of being logged, since the trigger may itself log data into the trace buffer. Thus we make sure the current event is committed before invoking those triggers. To do that, we split the trigger invocation in two - the first part (event_triggers_call()) checks the filter using the current trace record; if a command has the post_trigger flag set, it sets a bit for itself in the return value, otherwise it directly invoks the trigger. Once all commands have been either invoked or set their return flag, event_triggers_call() returns. The current record is then either committed or discarded; if any commands have deferred their triggers, those commands are finally invoked following the close of the current event by event_triggers_post_call(). To simplify the above and make it more efficient, the TRIGGER_COND bit is introduced, which is set only if a soft-disabled trigger needs to use the log record for filter testing or needs to wait until the current log record is closed. The syscall event invocation code is also changed in analogous ways. Because event triggers need to be able to create and free filters, this also adds a couple external wrappers for the existing create_filter and free_filter functions, which are too generic to be made extern functions themselves. Link: http://lkml.kernel.org/r/7164930759d8719ef460357f143d995406e4eead.1382622043.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-12-20tracing: Add basic event trigger frameworkTom Zanussi
Add a 'trigger' file for each trace event, enabling 'trace event triggers' to be set for trace events. 'trace event triggers' are patterned after the existing 'ftrace function triggers' implementation except that triggers are written to per-event 'trigger' files instead of to a single file such as the 'set_ftrace_filter' used for ftrace function triggers. The implementation is meant to be entirely separate from ftrace function triggers, in order to keep the respective implementations relatively simple and to allow them to diverge. The event trigger functionality is built on top of SOFT_DISABLE functionality. It adds a TRIGGER_MODE bit to the ftrace_event_file flags which is checked when any trace event fires. Triggers set for a particular event need to be checked regardless of whether that event is actually enabled or not - getting an event to fire even if it's not enabled is what's already implemented by SOFT_DISABLE mode, so trigger mode directly reuses that. Event trigger essentially inherit the soft disable logic in __ftrace_event_enable_disable() while adding a bit of logic and trigger reference counting via tm_ref on top of that in a new trace_event_trigger_enable_disable() function. Because the base __ftrace_event_enable_disable() code now needs to be invoked from outside trace_events.c, a wrapper is also added for those usages. The triggers for an event are actually invoked via a new function, event_triggers_call(), and code is also added to invoke them for ftrace_raw_event calls as well as syscall events. The main part of the patch creates a new trace_events_trigger.c file to contain the trace event triggers implementation. The standard open, read, and release file operations are implemented here. The open() implementation sets up for the various open modes of the 'trigger' file. It creates and attaches the trigger iterator and sets up the command parser. If opened for reading set up the trigger seq_ops. The read() implementation parses the event trigger written to the 'trigger' file, looks up the trigger command, and passes it along to that event_command's func() implementation for command-specific processing. The release() implementation does whatever cleanup is needed to release the 'trigger' file, like releasing the parser and trigger iterator, etc. A couple of functions for event command registration and unregistration are added, along with a list to add them to and a mutex to protect them, as well as an (initially empty) registration function to add the set of commands that will be added by future commits, and call to it from the trace event initialization code. also added are a couple trigger-specific data structures needed for these implementations such as a trigger iterator and a struct for trigger-specific data. A couple structs consisting mostly of function meant to be implemented in command-specific ways, event_command and event_trigger_ops, are used by the generic event trigger command implementations. They're being put into trace.h alongside the other trace_event data structures and functions, in the expectation that they'll be needed in several trace_event-related files such as trace_events_trigger.c and trace_events.c. The event_command.func() function is meant to be called by the trigger parsing code in order to add a trigger instance to the corresponding event. It essentially coordinates adding a live trigger instance to the event, and arming the triggering the event. Every event_command func() implementation essentially does the same thing for any command: - choose ops - use the value of param to choose either a number or count version of event_trigger_ops specific to the command - do the register or unregister of those ops - associate a filter, if specified, with the triggering event The reg() and unreg() ops allow command-specific implementations for event_trigger_op registration and unregistration, and the get_trigger_ops() op allows command-specific event_trigger_ops selection to be parameterized. When a trigger instance is added, the reg() op essentially adds that trigger to the triggering event and arms it, while unreg() does the opposite. The set_filter() function is used to associate a filter with the trigger - if the command doesn't specify a set_filter() implementation, the command will ignore filters. Each command has an associated trigger_type, which serves double duty, both as a unique identifier for the command as well as a value that can be used for setting a trigger mode bit during trigger invocation. The signature of func() adds a pointer to the event_command struct, used to invoke those functions, along with a command_data param that can be passed to the reg/unreg functions. This allows func() implementations to use command-specific blobs and supports code re-use. The event_trigger_ops.func() command corrsponds to the trigger 'probe' function that gets called when the triggering event is actually invoked. The other functions are used to list the trigger when needed, along with a couple mundane book-keeping functions. This also moves event_file_data() into trace.h so it can be used outside of trace_events.c. Link: http://lkml.kernel.org/r/316d95061accdee070aac8e5750afba0192fa5b9.1382622043.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Idea-by: Steve Rostedt <rostedt@goodmis.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-12-05tracing: Only run synchronize_sched() at instance deletion timeSteven Rostedt
It has been reported that boot up with FTRACE_SELFTEST enabled can take a very long time. There can be stalls of over a minute. This was tracked down to the synchronize_sched() called when a system call event is disabled. As the self tests enable and disable thousands of events, this makes the synchronize_sched() get called thousands of times. The synchornize_sched() was added with d562aff93bfb53 "tracing: Add support for SOFT_DISABLE to syscall events" which caused this regression (added in 3.13-rc1). The synchronize_sched() is to protect against the events being accessed when a tracer instance is being deleted. When an instance is being deleted all the events associated to it are unregistered. The synchronize_sched() makes sure that no more users are running when it finishes. Instead of calling synchronize_sched() for all syscall events, we only need to call it once, after the events are unregistered and before the instance is deleted. The event_mutex is held during this action to prevent new users from enabling events. Link: http://lkml.kernel.org/r/20131203124120.427b9661@gandalf.local.home Reported-by: Petr Mladek <pmladek@suse.cz> Acked-by: Tom Zanussi <tom.zanussi@linux.intel.com> Acked-by: Petr Mladek <pmladek@suse.cz> Tested-by: Petr Mladek <pmladek@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-11-05tracing: Add support for SOFT_DISABLE to syscall eventsTom Zanussi
The original SOFT_DISABLE patches didn't add support for soft disable of syscall events; this adds it. Add an array of ftrace_event_file pointers indexed by syscall number to the trace array and remove the existing enabled bitmaps, which as a result are now redundant. The ftrace_event_file structs in turn contain the soft disable flags we need for per-syscall soft disable accounting. Adding ftrace_event_files also means we can remove the USE_CALL_FILTER bit, thus enabling multibuffer filter support for syscall events. Link: http://lkml.kernel.org/r/6e72b566e85d8df8042f133efbc6c30e21fb017e.1382620672.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-11-05tracing: Update event filters for multibufferTom Zanussi
The trace event filters are still tied to event calls rather than event files, which means you don't get what you'd expect when using filters in the multibuffer case: Before: # echo 'bytes_alloc > 8192' > /sys/kernel/debug/tracing/events/kmem/kmalloc/filter # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/filter bytes_alloc > 8192 # mkdir /sys/kernel/debug/tracing/instances/test1 # echo 'bytes_alloc > 2048' > /sys/kernel/debug/tracing/instances/test1/events/kmem/kmalloc/filter # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/filter bytes_alloc > 2048 # cat /sys/kernel/debug/tracing/instances/test1/events/kmem/kmalloc/filter bytes_alloc > 2048 Setting the filter in tracing/instances/test1/events shouldn't affect the same event in tracing/events as it does above. After: # echo 'bytes_alloc > 8192' > /sys/kernel/debug/tracing/events/kmem/kmalloc/filter # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/filter bytes_alloc > 8192 # mkdir /sys/kernel/debug/tracing/instances/test1 # echo 'bytes_alloc > 2048' > /sys/kernel/debug/tracing/instances/test1/events/kmem/kmalloc/filter # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/filter bytes_alloc > 8192 # cat /sys/kernel/debug/tracing/instances/test1/events/kmem/kmalloc/filter bytes_alloc > 2048 We'd like to just move the filter directly from ftrace_event_call to ftrace_event_file, but there are a couple cases that don't yet have multibuffer support and therefore have to continue using the current event_call-based filters. For those cases, a new USE_CALL_FILTER bit is added to the event_call flags, whose main purpose is to keep the old behavior for those cases until they can be updated with multibuffer support; at that point, the USE_CALL_FILTER flag (and the new associated call_filter_check_discard() function) can go away. The multibuffer support also made filter_current_check_discard() redundant, so this change removes that function as well and replaces it with filter_check_discard() (or call_filter_check_discard() as appropriate). Link: http://lkml.kernel.org/r/f16e9ce4270c62f46b2e966119225e1c3cca7e60.1382620672.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-08-21tracing/syscalls: Annotate raw_init function with __initLi Zefan
init_syscall_trace() can only be called during kernel bootup only, so we can mark it and the functions it calls as __init. Link: http://lkml.kernel.org/r/51528E89.6080508@huawei.com Signed-off-by: Li Zefan <lizefan@huawei.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-07-18tracing/perf: Move the PERF_MAX_TRACE_SIZE check into perf_trace_buf_prepare()Oleg Nesterov
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 <peterz@infradead.org> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-07-18tracing/syscall: Avoid perf_trace_buf_*() if sys_data->perf_events is emptyOleg Nesterov
perf_trace_buf_prepare() + perf_trace_buf_submit(head, task => NULL) make no sense if hlist_empty(head). Change perf_syscall_enter/exit() to check sys_data->{enter,exit}_event->perf_events beforehand. Link: http://lkml.kernel.org/r/20130617170207.GA19806@redhat.com Acked-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-07-18tracing: Use trace_seq_puts()/trace_seq_putc() where possiblezhangwei(Jovi)
For string without format specifiers, use trace_seq_puts() or trace_seq_putc(). Link: http://lkml.kernel.org/r/51E3B3AC.1000605@huawei.com Signed-off-by: zhangwei(Jovi) <jovi.zhangwei@huawei.com> [ fixed a trace_seq_putc(s, " ") to trace_seq_putc(s, ' ') ] Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-07-02tracing: Fix irqs-off tag display in syscall tracingzhangwei(Jovi)
All syscall tracing irqs-off tags are wrong, the syscall enter entry doesn't disable irqs. [root@jovi tracing]#echo "syscalls:sys_enter_open" > set_event [root@jovi tracing]# cat trace # tracer: nop # # entries-in-buffer/entries-written: 13/13 #P:2 # # _-----=> irqs-off # / _----=> need-resched # | / _---=> hardirq/softirq # || / _--=> preempt-depth # ||| / delay # TASK-PID CPU# |||| TIMESTAMP FUNCTION # | | | |||| | | irqbalance-513 [000] d... 56115.496766: sys_open(filename: 804e1a6, flags: 0, mode: 1b6) irqbalance-513 [000] d... 56115.497008: sys_open(filename: 804e1bb, flags: 0, mode: 1b6) sendmail-771 [000] d... 56115.827982: sys_open(filename: b770e6d1, flags: 0, mode: 1b6) The reason is syscall tracing doesn't record irq_flags into buffer. The proper display is: [root@jovi tracing]#echo "syscalls:sys_enter_open" > set_event [root@jovi tracing]# cat trace # tracer: nop # # entries-in-buffer/entries-written: 14/14 #P:2 # # _-----=> irqs-off # / _----=> need-resched # | / _---=> hardirq/softirq # || / _--=> preempt-depth # ||| / delay # TASK-PID CPU# |||| TIMESTAMP FUNCTION # | | | |||| | | irqbalance-514 [001] .... 46.213921: sys_open(filename: 804e1a6, flags: 0, mode: 1b6) irqbalance-514 [001] .... 46.214160: sys_open(filename: 804e1bb, flags: 0, mode: 1b6) <...>-920 [001] .... 47.307260: sys_open(filename: 4e82a0c5, flags: 80000, mode: 0) Link: http://lkml.kernel.org/r/1365564393-10972-3-git-send-email-jovi.zhangwei@huawei.com Cc: stable@vger.kernel.org # 2.6.35 Signed-off-by: zhangwei(Jovi) <jovi.zhangwei@huawei.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-03-15tracing: Fix comment about prefix in arch_syscall_match_sym_name()zhangwei(Jovi)
ppc64 has its own syscall prefix like ".SyS" or ".sys". Make the comment in arch_syscall_match_sym_name() more understandable. Link: http://lkml.kernel.org/r/513D842F.40205@huawei.com Signed-off-by: zhangwei(Jovi) <jovi.zhangwei@huawei.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-03-15tracing: Consolidate max_tr into main trace_array structureSteven Rostedt (Red Hat)
Currently, the way the latency tracers and snapshot feature works is to have a separate trace_array called "max_tr" that holds the snapshot buffer. For latency tracers, this snapshot buffer is used to swap the running buffer with this buffer to save the current max latency. The only items needed for the max_tr is really just a copy of the buffer itself, the per_cpu data pointers, the time_start timestamp that states when the max latency was triggered, and the cpu that the max latency was triggered on. All other fields in trace_array are unused by the max_tr, making the max_tr mostly bloat. This change removes the max_tr completely, and adds a new structure called trace_buffer, that holds the buffer pointer, the per_cpu data pointers, the time_start timestamp, and the cpu where the latency occurred. The trace_array, now has two trace_buffers, one for the normal trace and one for the max trace or snapshot. By doing this, not only do we remove the bloat from the max_trace but the instances of traces can now use their own snapshot feature and not have just the top level global_trace have the snapshot feature and latency tracers for itself. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-03-15tracing: Fix some section mismatch warningsLi Zefan
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 <fengguang.wu@intel.com> Signed-off-by: Li Zefan <lizefan@huawei.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-03-15tracing/syscalls: Annotate field-defining functions with __initLi Zefan
These two functions are called during kernel boot only. Link: http://lkml.kernel.org/r/51258796.7020704@huawei.com Signed-off-by: Li Zefan <lizefan@huawei.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-03-15tracing: Make syscall events suitable for multiple buffersSteven Rostedt
Currently the syscall events record into the global buffer. But if multiple buffers are in place, then we need to have syscall events record in the proper buffers. By adding descriptors to pass to the syscall event functions, the syscall events can now record into the buffers that have been assigned to them (one event may be applied to mulitple buffers). This will allow tracing high volume syscalls along with seldom occurring syscalls without losing the seldom syscall events. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-02-12tracing/syscalls: Allow archs to ignore tracing compat syscallsSteven Rostedt
The tracing of ia32 compat system calls has been a bit of a pain as they use different system call numbers than the 64bit equivalents. I wrote a simple 'lls' program that lists files. I compiled it as a i686 ELF binary and ran it under a x86_64 box. This is the result: echo 0 > /debug/tracing/tracing_on echo 1 > /debug/tracing/events/syscalls/enable echo 1 > /debug/tracing/tracing_on ; ./lls ; echo 0 > /debug/tracing/tracing_on grep lls /debug/tracing/trace [.. skipping calls before TS_COMPAT is set ...] lls-1127 [005] d... 936.409188: sys_recvfrom(fd: 0, ubuf: 4d560fc4, size: 0, flags: 8048034, addr: 8, addr_len: f7700420) lls-1127 [005] d... 936.409190: sys_recvfrom -> 0x8a77000 lls-1127 [005] d... 936.409211: sys_lgetxattr(pathname: 0, name: 1000, value: 3, size: 22) lls-1127 [005] d... 936.409215: sys_lgetxattr -> 0xf76ff000 lls-1127 [005] d... 936.409223: sys_dup2(oldfd: 4d55ae9b, newfd: 4) lls-1127 [005] d... 936.409228: sys_dup2 -> 0xfffffffffffffffe lls-1127 [005] d... 936.409236: sys_newfstat(fd: 4d55b085, statbuf: 80000) lls-1127 [005] d... 936.409242: sys_newfstat -> 0x3 lls-1127 [005] d... 936.409243: sys_removexattr(pathname: 3, name: ffcd0060) lls-1127 [005] d... 936.409244: sys_removexattr -> 0x0 lls-1127 [005] d... 936.409245: sys_lgetxattr(pathname: 0, name: 19614, value: 1, size: 2) lls-1127 [005] d... 936.409248: sys_lgetxattr -> 0xf76e5000 lls-1127 [005] d... 936.409248: sys_newlstat(filename: 3, statbuf: 19614) lls-1127 [005] d... 936.409249: sys_newlstat -> 0x0 lls-1127 [005] d... 936.409262: sys_newfstat(fd: f76fb588, statbuf: 80000) lls-1127 [005] d... 936.409279: sys_newfstat -> 0x3 lls-1127 [005] d... 936.409279: sys_close(fd: 3) lls-1127 [005] d... 936.421550: sys_close -> 0x200 lls-1127 [005] d... 936.421558: sys_removexattr(pathname: 3, name: ffcd00d0) lls-1127 [005] d... 936.421560: sys_removexattr -> 0x0 lls-1127 [005] d... 936.421569: sys_lgetxattr(pathname: 4d564000, name: 1b1abc, value: 5, size: 802) lls-1127 [005] d... 936.421574: sys_lgetxattr -> 0x4d564000 lls-1127 [005] d... 936.421575: sys_capget(header: 4d70f000, dataptr: 1000) lls-1127 [005] d... 936.421580: sys_capget -> 0x0 lls-1127 [005] d... 936.421580: sys_lgetxattr(pathname: 4d710000, name: 3000, value: 3, size: 812) lls-1127 [005] d... 936.421589: sys_lgetxattr -> 0x4d710000 lls-1127 [005] d... 936.426130: sys_lgetxattr(pathname: 4d713000, name: 2abc, value: 3, size: 32) lls-1127 [005] d... 936.426141: sys_lgetxattr -> 0x4d713000 lls-1127 [005] d... 936.426145: sys_newlstat(filename: 3, statbuf: f76ff3f0) lls-1127 [005] d... 936.426146: sys_newlstat -> 0x0 lls-1127 [005] d... 936.431748: sys_lgetxattr(pathname: 0, name: 1000, value: 3, size: 22) Obviously I'm not calling newfstat with a fd of 4d55b085. The calls are obviously incorrect, and confusing. Other efforts have been made to fix this: https://lkml.org/lkml/2012/3/26/367 But the real solution is to rewrite the syscall internals and come up with a fixed solution. One that doesn't require all the kluge that the current solution has. Thus for now, instead of outputting incorrect data, simply ignore them. With this patch the changes now have: #> grep lls /debug/tracing/trace #> Compat system calls simply are not traced. If users need compat syscalls, then they should just use the raw syscall tracepoints. For an architecture to make their compat syscalls ignored, it must define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS (done in asm/ftrace.h) and also define an arch_trace_is_compat_syscall() function that will return true if the current task should ignore tracing the syscall. I want to stress that this change does not affect actual syscalls in any way, shape or form. It is only used within the tracing system and doesn't interfere with the syscall logic at all. The changes are consolidated nicely into trace_syscalls.c and asm/ftrace.h. I had to make one small modification to asm/thread_info.h and that was to remove the include of asm/ftrace.h. As asm/ftrace.h required the current_thread_info() it was causing include hell. That include was added back in 2008 when the function graph tracer was added: commit caf4b323 "tracing, x86: add low level support for ftrace return tracing" It does not need to be included there. Link: http://lkml.kernel.org/r/1360703939.21867.99.camel@gandalf.local.home Acked-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-01-21tracing/syscalls: Make local functions staticFengguang Wu
Some functions in the syscall tracing is used only locally to the file, but they are labeled global. Convert them to static functions. Signed-off-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-10-31tracing: Cleanup unnecessary function declarationsVaibhav Nagarnaik
The functions defined in include/trace/syscalls.h are not used directly since struct ftrace_event_class was introduced. Remove them from the header file and rearrange the ftrace_event_class declarations in trace_syscalls.c. Link: http://lkml.kernel.org/r/1339112785-21806-2-git-send-email-vnagarnaik@google.com Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@google.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-09-24trace: Move trace event enable from fs_initcall to core_initcallEzequiel Garcia
This patch splits trace event initialization in two stages: * ftrace enable * sysfs event entry creation This allows to capture trace events from an earlier point by using 'trace_event' kernel parameter and is important to trace boot-up allocations. Note that, in order to enable events at core_initcall, it's necessary to move init_ftrace_syscalls() from core_initcall to early_initcall. Link: http://lkml.kernel.org/r/1347461277-25302-1-git-send-email-elezegarcia@gmail.com Signed-off-by: Ezequiel Garcia <elezegarcia@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-08-17tracing/syscalls: Fix perf syscall tracing when syscall_nr == -1Will Deacon
syscall_get_nr can return -1 in the case that the task is not executing a system call. This patch fixes perf_syscall_{enter,exit} to check that the syscall number is valid before using it as an index into a bitmap. Link: http://lkml.kernel.org/r/1345137254-7377-1-git-send-email-will.deacon@arm.com Cc: Jason Baron <jbaron@redhat.com> Cc: Wade Farnsworth <wade_farnsworth@mentor.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-31perf/trace: Add ability to set a target task for eventsAndrew Vagin
A few events are interesting not only for a current task. For example, sched_stat_* events are interesting for a task which wakes up. For this reason, it will be good if such events will be delivered to a target task too. Now a target task can be set by using __perf_task(). The original idea and a draft patch belongs to Peter Zijlstra. I need these events for profiling sleep times. sched_switch is used for getting callchains and sched_stat_* is used for getting time periods. These events are combined in user space, then it can be analyzed by perf tools. Inspired-by: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Arun Sharma <asharma@fb.com> Signed-off-by: Andrew Vagin <avagin@openvz.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1342016098-213063-1-git-send-email-avagin@openvz.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-02-21ftrace, perf: Add add/del tracepoint perf registration actionsJiri Olsa
Adding TRACE_REG_PERF_ADD and TRACE_REG_PERF_DEL to handle perf event schedule in/out actions. The add action is invoked for when the perf event is scheduled in, while the del action is invoked when the event is scheduled out. Link: http://lkml.kernel.org/r/1329317514-8131-4-git-send-email-jolsa@redhat.com Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-02-21ftrace, perf: Add open/close tracepoint perf registration actionsJiri Olsa
Adding TRACE_REG_PERF_OPEN and TRACE_REG_PERF_CLOSE to differentiate register/unregister from open/close actions. The register/unregister actions are invoked for the first/last tracepoint user when opening/closing the event. The open/close actions are invoked for each tracepoint user when opening/closing the event. Link: http://lkml.kernel.org/r/1329317514-8131-3-git-send-email-jolsa@redhat.com Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Jiri Olsa <jolsa@redhat.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-02-13tracing/trivial: Use kcalloc instead of kzalloc to allocate arrayThomas Meyer
The advantage of kcalloc is, that will prevent integer overflows which could result from the multiplication of number of elements and size and it is also a bit nicer to read. The semantic patch that makes this change is available in https://lkml.org/lkml/2011/11/25/107 Link: http://lkml.kernel.org/r/1322600880.1534.347.camel@localhost.localdomain Signed-off-by: Thomas Meyer <thomas@m3y3r.de> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-10-31kernel: Add <linux/module.h> to files using it implicitlyPaul Gortmaker
These files are doing things like module_put and try_module_get so they need to call out the module.h for explicit inclusion, rather than getting it via <linux/device.h> which we ideally want to remove the module.h inclusion from. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-02-07tracing/syscalls: Early terminate search for sys_ni_syscallIan Munsie
Many system calls are unimplemented and mapped to sys_ni_syscall, but at boot ftrace would still search through every syscall metadata entry for a match which wouldn't be there. This patch adds causes the search to terminate early if the system call is not mapped. Signed-off-by: Ian Munsie <imunsie@au1.ibm.com> LKML-Reference: <1296703645-18718-7-git-send-email-imunsie@au1.ibm.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-02-07tracing/syscalls: Allow arch specific syscall symbol matchingIan Munsie
Some architectures have unusual symbol names and the generic code to match the symbol name with the function name for the syscall metadata will fail. For example, symbols on PPC64 start with a period and the generic code will fail to match them. This patch moves the match logic out into a separate function which an arch can override by defining ARCH_HAS_SYSCALL_MATCH_SYM_NAME in asm/ftrace.h and implementing arch_syscall_match_sym_name. Signed-off-by: Ian Munsie <imunsie@au1.ibm.com> LKML-Reference: <1296703645-18718-5-git-send-email-imunsie@au1.ibm.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-02-07tracing/syscalls: Make arch_syscall_addr weakIan Munsie
Some architectures use non-trivial system call tables and will not work with the generic arch_syscall_addr code. For example, PowerPC64 uses a table of twin long longs. This patch makes the generic arch_syscall_addr weak to allow architectures with non-trivial system call tables to override it. Signed-off-by: Ian Munsie <imunsie@au1.ibm.com> LKML-Reference: <1296703645-18718-4-git-send-email-imunsie@au1.ibm.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-02-07tracing/syscalls: Convert redundant syscall_nr checks into WARN_ONIan Munsie
With the ftrace events now checking if the syscall_nr is valid upon initialisation it should no longer be possible to register or unregister a syscall event without a valid syscall_nr since they should not be created. This adds a WARN_ON_ONCE in the register and unregister functions to locate potential regressions in the future. Signed-off-by: Ian Munsie <imunsie@au1.ibm.com> LKML-Reference: <1296703645-18718-3-git-send-email-imunsie@au1.ibm.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-02-07tracing/syscalls: Don't add events for unmapped syscallsIan Munsie
FTRACE_SYSCALLS would create events for each and every system call, even if it had failed to map the system call's name with it's number. This resulted in a number of events being created that would not behave as expected. This could happen, for example, on architectures who's symbol names are unusual and will not match the system call name. It could also happen with system calls which were mapped to sys_ni_syscall. This patch changes the default system call number in the metadata to -1. If the system call name from the metadata is not successfully mapped to a system call number during boot, than the event initialisation routine will now return an error, preventing the event from being created. Signed-off-by: Ian Munsie <imunsie@au1.ibm.com> LKML-Reference: <1296703645-18718-2-git-send-email-imunsie@au1.ibm.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-02-03tracing: Replace syscall_meta_data struct array with pointer arraySteven Rostedt
Currently the syscall_meta structures for the syscall tracepoints are placed in the __syscall_metadata section, and at link time, the linker makes one large array of all these syscall metadata structures. On boot up, this array is read (much like the initcall sections) and the syscall data is processed. The problem is that there is no guarantee that gcc will place complex structures nicely together in an array format. Two structures in the same file may be placed awkwardly, because gcc has no clue that they are suppose to be in an array. A hack was used previous to force the alignment to 4, to pack the structures together. But this caused alignment issues with other architectures (sparc). Instead of packing the structures into an array, the structures' addresses are now put into the __syscall_metadata section. As pointers are always the natural alignment, gcc should always pack them tightly together (otherwise initcall, extable, etc would also fail). By having the pointers to the structures in the section, we can still iterate the trace_events without causing unnecessary alignment problems with other architectures, or depending on the current behaviour of gcc that will likely change in the future just to tick us kernel developers off a little more. The __syscall_metadata section is also moved into the .init.data section as it is now only needed at boot up. Suggested-by: David Miller <davem@davemloft.net> Acked-by: David S. Miller <davem@davemloft.net> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-01-14tracing: Remove syscall_exit_fieldsLai Jiangshan
There is no need for syscall_exit_fields as the syscall exit event class can already host the fields in its structure, like most other trace events do by default. Use that default behavior instead. Following this scheme, we don't need anymore to override the get_fields() callback of the syscall exit event class either. Hence both syscall_exit_fields and syscall_get_exit_fields() can be removed. Also changed some indentation to keep the following under 80 characters: ".fields = LIST_HEAD_INIT(event_class_syscall_exit.fields)," Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> LKML-Reference: <4D301C0E.8090408@cn.fujitsu.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2010-06-28tracing: Use a global field list for all syscall exit eventsLi Zefan
All syscall exit events have the same fields. The kernel size drops 2.5K: text data bss dec hex filename 7018612 2034376 7251132 16304120 f8c7f8 vmlinux.o.orig 7018612 2031888 7251132 16301632 f8be40 vmlinux.o Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> LKML-Reference: <4BFA3746.8070100@cn.fujitsu.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>