Since the ring buffer is lockless, there is no need to disable ftrace on
CPU. And no one doing so: after commit 68179686ac67cb ("tracing: Remove
ftrace_disable/enable_cpu()") ftrace_cpu_disabled stays the same after
initialization, nothing changes it.
ftrace_cpu_disabled shouldn't be used by any external module since it
disables only function and graph_function tracers but not any other
tracer.
Link: http://lkml.kernel.org/r/1446836846-22239-1-git-send-email-0x7f454c46@gmail.com
Signed-off-by: Dmitry Safonov <0x7f454c46@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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>
The sleep-time and graph-time options are only for the function graph tracer and are not used by anything else. As tracer options are now visible when the tracer is not activated, its better to move the function graph specific tracer options into the function graph tracer. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Jungseok Lee noticed the following:
Currently, row's width of 7-digit duration numbers not aligned with
other cases like the following example.
3) $ 3999884 us | }
3) | finish_task_switch() {
3) 0.365 us | _raw_spin_unlock_irq();
3) 3.333 us | }
3) $ 3999976 us | }
3) $ 3999979 us | } /* schedule */
As adding a single white space in case of 7-digit numbers, the format
could be unified easily as follows.
3) $ 2237472 us | }
3) | finish_task_switch() {
3) 0.364 us | _raw_spin_unlock_irq();
3) 3.125 us | }
3) $ 2237556 us | }
3) $ 2237559 us | } /* schedule */
Instead of making a special case for 7-digit numbers, the logic
of the len and the space loop is slightly modified to make the
two cases have the same format.
Link: http://lkml.kernel.org/r/1436626300-1679-2-git-send-email-jungseoklee85@gmail.com
Reported-by: Jungseok Lee <jungseoklee85@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
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>
The name "ftrace" really refers to the function hook infrastructure. It is not about the trace_events. The functions (un)register_ftrace_event() is really about trace_events, and the name should be register_trace_event() instead. Also renamed ftrace_event_reg() to trace_event_reg() for the same reason. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Pull tracing fixes from Steven Rostedt: "This adds three fixes for the tracing code. The first is a bug when ftrace_dump_on_oops is triggered in atomic context and function graph tracer is the tracer that is being reported. The second fix is bad parsing of the trace_events from the kernel command line, where it would ignore specific events if the system name is used with defining the event(it enables all events within the system). The last one is a fix to the TRACE_DEFINE_ENUM(), where a check was missing to see if the ptr was incremented to the end of the string, but the loop increments it again and can miss the nul delimiter to stop processing" * tag 'trace-v4.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Fix possible out of bounds memory access when parsing enums tracing: Fix incorrect enabling of trace events by boot cmdline tracing: Handle ftrace_dump() atomic context in graph_trace_open()
graph_trace_open() can be called in atomic context from ftrace_dump(). Use GFP_ATOMIC for the memory allocations when that's the case, in order to avoid the following splat. BUG: sleeping function called from invalid context at mm/slab.c:2849 in_atomic(): 1, irqs_disabled(): 128, pid: 0, name: swapper/0 Backtrace: .. [<8004dc94>] (__might_sleep) from [<801371f4>] (kmem_cache_alloc_trace+0x160/0x238) r7:87800040 r6:000080d0 r5:810d16e8 r4:000080d0 [<80137094>] (kmem_cache_alloc_trace) from [<800cbd60>] (graph_trace_open+0x30/0xd0) r10:00000100 r9:809171a8 r8:00008e28 r7:810d16f0 r6:00000001 r5:810d16e8 r4:810d16f0 [<800cbd30>] (graph_trace_open) from [<800c79c4>] (trace_init_global_iter+0x50/0x9c) r8:00008e28 r7:808c853c r6:00000001 r5:810d16e8 r4:810d16f0 r3:800cbd30 [<800c7974>] (trace_init_global_iter) from [<800c7aa0>] (ftrace_dump+0x90/0x2ec) r4:810d2580 r3:00000000 [<800c7a10>] (ftrace_dump) from [<80414b2c>] (sysrq_ftrace_dump+0x1c/0x20) r10:00000100 r9:809171a8 r8:808f6e7c r7:00000001 r6:00000007 r5:0000007a r4:808d5394 [<80414b10>] (sysrq_ftrace_dump) from [<800169b8>] (return_to_handler+0x0/0x18) [<80415498>] (__handle_sysrq) from [<800169b8>] (return_to_handler+0x0/0x18) r8:808c8100 r7:808c8444 r6:00000101 r5:00000010 r4:84eb3210 [<80415668>] (handle_sysrq) from [<800169b8>] (return_to_handler+0x0/0x18) [<8042a760>] (pl011_int) from [<800169b8>] (return_to_handler+0x0/0x18) r10:809171bc r9:809171a8 r8:00000001 r7:00000026 r6:808c6000 r5:84f01e60 r4:8454fe00 [<8007782c>] (handle_irq_event_percpu) from [<80077b44>] (handle_irq_event+0x4c/0x6c) r10:808c7ef0 r9:87283e00 r8:00000001 r7:00000000 r6:8454fe00 r5:84f01e60 r4:84f01e00 [<80077af8>] (handle_irq_event) from [<8007aa28>] (handle_fasteoi_irq+0xf0/0x1ac) r6:808f52a4 r5:84f01e60 r4:84f01e00 r3:00000000 [<8007a938>] (handle_fasteoi_irq) from [<80076dc0>] (generic_handle_irq+0x3c/0x4c) r6:00000026 r5:00000000 r4:00000026 r3:8007a938 [<80076d84>] (generic_handle_irq) from [<80077128>] (__handle_domain_irq+0x8c/0xfc) r4:808c1e38 r3:0000002e [<8007709c>] (__handle_domain_irq) from [<800087b8>] (gic_handle_irq+0x34/0x6c) r10:80917748 r9:00000001 r8:88802100 r7:808c7ef0 r6:808c8fb0 r5:00000015 r4:8880210c r3:808c7ef0 [<80008784>] (gic_handle_irq) from [<80014044>] (__irq_svc+0x44/0x7c) Link: http://lkml.kernel.org/r/1428953721-31349-1-git-send-email-rabin@rab.in Link: http://lkml.kernel.org/r/1428957012-2319-1-git-send-email-rabin@rab.in Cc: stable@vger.kernel.org # 3.13+ Signed-off-by: Rabin Vincent <rabin@rab.in> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
debugfs was fine for the tracing facility as a quick way to get an interface. Now that tracing has matured, it should separate itself from debugfs such that it can be mounted separately without needing to mount all of debugfs with it. That is, users resist using tracing because it requires mounting debugfs. Having tracing have its own file system lets users get the features of tracing without needing to bring in the rest of the kernel's debug infrastructure. Another reason for tracefs is that debubfs does not support mkdir. Currently, to create instances, one does a mkdir in the tracing/instance directory. This is implemented via a hack that forces debugfs to do something it is not intended on doing. By converting over to tracefs, this hack can be removed and mkdir can be properly implemented. This patch does not address this yet, but it lays the ground work for that to be done. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
tracing_init_dentry() will soon return NULL as a valid pointer for the top level tracing directroy. NULL can not be used as an error value. Instead, switch to ERR_PTR() and check the return status with IS_ERR(). Signed-off-by: Steven Rostedt <rostedt@goodmis.org>