[PATCHv2 0/2] tracing,mm - add kernel pagefault tracepoint for x86 & x86_64

[Jiri Olsa <jolsa@redhat.com>]

This provides a tracepoint to trace kernel pagefault event
for x86 and x86_64 architectures.

There's a problem with this tracepoint when having the
userstacktrace option enabled, since it might generated
the page fault itself. The 1/2 patch address this issue.

v2 changes:
- replaced regs for error_code in page fault trace
- swapped the patch order not to introduce the regression
- minor code style change

attached patches:
1/2 tracing - fix recursive user stack trace
2/2 tracing,mm - add kernel pagefault tracepoint for x86 & x86_64

wbr,
jirka
---
 arch/x86/mm/fault.c         |   32 +++++++++++++++++++++-----------
 include/trace/events/kmem.h |   22 ++++++++++++++++++++++
 kernel/trace/trace.c        |   17 +++++++++++++++++
 3 files changed, 60 insertions(+), 11 deletions(-)