[PATCH v2 0/5] powerpc/ftrace: Add support for ftrace_modify_call() and a few other fixes

Naveen N. Rao naveen.n.rao at linux.vnet.ibm.com
Wed Mar 21 21:43:17 AEDT 2018


The first two patches fix a kernel oops when function tracing is enabled 
while using KVM and are v2 of the patches posted at:
https://www.mail-archive.com/linuxppc-dev@lists.ozlabs.org/msg130548.html

Patch 3 is a new patch that tightens how we detect _mcount() call sites 
for -mprofile-kernel during module loading.

The last two patches implement support for ftrace_caller() to 
conditionally save the register state. The existing ftrace_caller() is 
renamed to ftrace_regs_caller() since we save the entire pt_regs today.  
A new implementation of ftrace_caller() that saves the minimum register 
state is provided. We switch between the two variants through 
ftrace_modify_call(). The necessary support to call into the two 
different variants from modules is also added.


- Naveen


Naveen N. Rao (5):
  powerpc64/ftrace: Add a field in paca to disable ftrace in unsafe code
    paths
  powerpc64/ftrace: Disable ftrace during kvm guest entry/exit
  powerpc64/module: Tighten detection of mcount call sites with
    -mprofile-kernel
  powerpc64/ftrace: Use the generic version of ftrace_replace_code()
  powerpc64/ftrace: Implement support for ftrace_regs_caller()

 arch/powerpc/include/asm/ftrace.h              |   2 -
 arch/powerpc/include/asm/module.h              |   3 +
 arch/powerpc/include/asm/paca.h                |   1 +
 arch/powerpc/kernel/asm-offsets.c              |   1 +
 arch/powerpc/kernel/module_64.c                |  43 +++--
 arch/powerpc/kernel/trace/ftrace.c             | 210 ++++++++++++++++++++-----
 arch/powerpc/kernel/trace/ftrace_64_mprofile.S |  85 +++++++++-
 arch/powerpc/kernel/trace/ftrace_64_pg.S       |   4 +
 arch/powerpc/kvm/book3s_hv_rmhandlers.S        |   8 +
 9 files changed, 294 insertions(+), 63 deletions(-)

-- 
2.16.2



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