[RFC PATCH 07/14] powerpc/ftrace: Remove dead code

From: Naveen N. Rao
Date: Thu Nov 26 2020 - 13:10:35 EST


ftrace_plt_tramps[] was intended to speed up skipping plt branches, but
the code wasn't completed. It is also not significantly better than
reading and decoding the instruction. Remove the same.

Signed-off-by: Naveen N. Rao <naveen.n.rao@xxxxxxxxxxxxxxxxxx>
---
arch/powerpc/kernel/trace/ftrace.c | 8 --------
1 file changed, 8 deletions(-)

diff --git a/arch/powerpc/kernel/trace/ftrace.c b/arch/powerpc/kernel/trace/ftrace.c
index 42761ebec9f755..4fe5f373172fd2 100644
--- a/arch/powerpc/kernel/trace/ftrace.c
+++ b/arch/powerpc/kernel/trace/ftrace.c
@@ -332,7 +332,6 @@ static int setup_mcount_compiler_tramp(unsigned long tramp)
struct ppc_inst op;
unsigned long ptr;
struct ppc_inst instr;
- static unsigned long ftrace_plt_tramps[NUM_FTRACE_TRAMPS];

/* Is this a known long jump tramp? */
for (i = 0; i < NUM_FTRACE_TRAMPS; i++)
@@ -341,13 +340,6 @@ static int setup_mcount_compiler_tramp(unsigned long tramp)
else if (ftrace_tramps[i] == tramp)
return 0;

- /* Is this a known plt tramp? */
- for (i = 0; i < NUM_FTRACE_TRAMPS; i++)
- if (!ftrace_plt_tramps[i])
- break;
- else if (ftrace_plt_tramps[i] == tramp)
- return -1;
-
/* New trampoline -- read where this goes */
if (probe_kernel_read_inst(&op, (void *)tramp)) {
pr_debug("Fetching opcode failed.\n");
--
2.25.4