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| author |   Steven Rostedt (Red Hat) <rostedt@goodmis.org> | 2014-11-24 13:21:09 -0500 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2014-12-01 14:07:39 -0500 |
| commit | 094dfc545139510f251b9595850aa63fe2a8c131 (patch) | |
| tree | 1d92fc26e6a38cbd3938e1ab1fe2fbf5584bfb7a /arch/x86/kernel/mcount_64.S | |
| parent | ftrace/x86: Rename MCOUNT_SAVE_FRAME and add more detailed comments (diff) | |
| download | linux-dev-094dfc545139510f251b9595850aa63fe2a8c131.tar.xz linux-dev-094dfc545139510f251b9595850aa63fe2a8c131.zip | |
ftrace/x86: Have save_mcount_regs store RIP in %rdi for first parameter
Instead of having save_mcount_regs store the RIP in %rdx as a temp register
to place it in the proper location of the pt_regs on the stack. Use the
%rdi register as the temp register. This lets us remove the extra store
in the ftrace_caller_setup macro.
Link: http://lkml.kernel.org/r/CA+55aFwF+qCGSKdGaEgW4p6N65GZ5_XTV=1NbtWDvxnd5yYLiw@mail.gmail.com
Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1411262304010.3961@nanos
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to '')
| -rw-r--r-- | arch/x86/kernel/mcount_64.S | 7 |
1 files changed, 3 insertions, 4 deletions
diff --git a/arch/x86/kernel/mcount_64.S b/arch/x86/kernel/mcount_64.S index 0a693d011980..4f1b27642495 100644 --- a/arch/x86/kernel/mcount_64.S +++ b/arch/x86/kernel/mcount_64.S @@ -51,8 +51,8 @@ movq %r8, R8(%rsp) movq %r9, R9(%rsp) /* Move RIP to its proper location */ - movq SS+8(%rsp), %rdx - movq %rdx, RIP(%rsp) + movq SS+8(%rsp), %rdi + movq %rdi, RIP(%rsp) .endm .macro restore_mcount_regs skip=0 @@ -75,8 +75,7 @@ GLOBAL(\trace_label) /* Load the ftrace_ops into the 3rd parameter */ movq function_trace_op(%rip), %rdx - /* Load ip into the first parameter */ - movq RIP(%rsp), %rdi + /* %rdi already has %rip from the save_mcount_regs macro */ subq $MCOUNT_INSN_SIZE, %rdi /* Load the parent_ip into the second parameter */ #ifdef CC_USING_FENTRY |