x86/ftrace: Add stack frame pointer to ftrace_caller
authorSteven Rostedt (VMware) <rostedt@goodmis.org>
Thu, 23 Mar 2017 14:33:50 +0000 (10:33 -0400)
committerThomas Gleixner <tglx@linutronix.de>
Fri, 24 Mar 2017 09:14:07 +0000 (10:14 +0100)
commite6928e58d4d4a02f88838945f792c107623314ac
treeab933b16e09edd0dc24772fb39df2a0011d91dd0
parent3d82c59c6e3cb168284d9b0a1143415d9c98ae40
x86/ftrace: Add stack frame pointer to ftrace_caller

The function hook ftrace_caller does not create its own stack frame, and
this causes the ftrace stack trace to miss the first function when doing
stack traces.

 # echo schedule:stacktrace > /sys/kernel/tracing/set_ftrace_filter

Before:
         <idle>-0     [002] .N..    29.865807: <stack trace>
 => cpu_startup_entry
 => start_secondary
 => startup_32_smp
           <...>-7     [001] ....    29.866509: <stack trace>
 => kthread
 => ret_from_fork
           <...>-1     [000] ....    29.865377: <stack trace>
 => poll_schedule_timeout
 => do_select
 => core_sys_select
 => SyS_select
 => do_fast_syscall_32
 => entry_SYSENTER_32

After:
          <idle>-0     [002] .N..    31.234853: <stack trace>
 => do_idle
 => cpu_startup_entry
 => start_secondary
 => startup_32_smp
           <...>-7     [003] ....    31.235140: <stack trace>
 => rcu_gp_kthread
 => kthread
 => ret_from_fork
           <...>-1819  [000] ....    31.264172: <stack trace>
 => schedule_hrtimeout_range
 => poll_schedule_timeout
 => do_sys_poll
 => SyS_ppoll
 => do_fast_syscall_32
 => entry_SYSENTER_32

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20170323143445.771707773@goodmis.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
arch/x86/kernel/ftrace_32.S