[RFC][PATCH 00/18 v2] ftrace/rcu: Handle unsafe RCU functions and ftrace callbacks

[Steven Rostedt <rostedt@goodmis.org>]

This is my final draft of the patches. I'm starting to run them
through my formal tests now. They may change depending on the outcome
of the tests.

I'm also a bit tired, and I added the change logs last. Thus I may
need to go back and fix the change logs up too. But the code was done
when I was rather spunky. But that doesn't mean I didn't break anything.

Anyway, let me know what you think. I'm going to need acks for the
places I added the FTRACE_UNSAFE_RCU() annotations.

I added a checker that traces all functions with the non RCU safe
settings, and did a rcu_read_lock() with PROVE_RCU enabled. This caught
several functions that needed to be annotated. There may be more, but
the test gives us a way to find out.

There's some improvements that can be done to these patches, but for
3.12, I think this version is good enough. We can do the improvements
for 3.13.

Well, enjoy.

-- Steve


Steven Rostedt (Red Hat) (18):
      ftrace: Add hash list to save RCU unsafe functions
      ftrace: Do not set ftrace records for unsafe RCU when not allowed
      ftrace: Set ftrace internal function tracing RCU safe
      ftrace: Add test for ops against unsafe RCU functions in callback
      ftrace: Do not display non safe RCU functions in available_filter_functions
      ftrace: Add rcu_unsafe_filter_functions file
      ftrace: Add selftest to check if RCU unsafe functions are filtered properly
      ftrace/rcu: Do not trace debug_lockdep_rcu_enabled()
      ftrace: Fix a slight race in modifying what function callback gets traced
      ftrace: Create a RCU unsafe checker
      ftrace: Adde infrastructure to stop RCU unsafe checker from checking
      ftrace: Disable RCU unsafe checker when function graph is enabled
      ftrace: Disable the RCU unsafe checker when irqsoff is enabled
      ftrace/lockdep: Have the RCU lockdep splat show what function triggered
      ftrace/rcu: Mark functions that are RCU unsafe
      rcu/irq/x86: Mark functions that are RCU unsafe
      ftrace/cpuidle/x86: Mark functions that are RCU unsafe
      ftrace/sched: Mark functions that are RCU unsafe

----
 arch/x86/kernel/apic/apic.c           |    2 +
 arch/x86/kernel/irq.c                 |    1 +
 arch/x86/kernel/irq_work.c            |    3 +
 arch/x86/kernel/process.c             |    2 +
 arch/x86/kernel/smp.c                 |    8 ++
 drivers/cpuidle/cpuidle.c             |    2 +
 include/asm-generic/vmlinux.lds.h     |   10 ++
 include/linux/ftrace.h                |   46 +++++++
 kernel/cpu/idle.c                     |    2 +
 kernel/lockdep.c                      |    2 +
 kernel/rcupdate.c                     |    2 +-
 kernel/rcutiny.c                      |    1 +
 kernel/rcutree.c                      |    7 +
 kernel/sched/core.c                   |    2 +
 kernel/softirq.c                      |    2 +
 kernel/trace/Kconfig                  |   22 ++++
 kernel/trace/ftrace.c                 |  231 +++++++++++++++++++++++++++++++--
 kernel/trace/trace.h                  |   11 ++
 kernel/trace/trace_functions.c        |   76 ++++++++++-
 kernel/trace/trace_irqsoff.c          |   16 ++-
 kernel/trace/trace_selftest.c         |   94 ++++++++++++++
 kernel/trace/trace_selftest_dynamic.c |    7 +
 22 files changed, 532 insertions(+), 17 deletions(-)