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

From: "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com>
To: Steven Rostedt <rostedt@goodmis.org>,
	Michael Ellerman <mpe@ellerman.id.au>
Cc: <linux-kernel@vger.kernel.org>, <linuxppc-dev@lists.ozlabs.org>
Subject: [RFC PATCH 07/14] powerpc/ftrace: Remove dead code
Date: Thu, 26 Nov 2020 23:38:44 +0530	[thread overview]
Message-ID: <bdc3710137c4bda8393532a789558bed22507cfe.1606412433.git.naveen.n.rao@linux.vnet.ibm.com> (raw)
In-Reply-To: <cover.1606412433.git.naveen.n.rao@linux.vnet.ibm.com>

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@linux.vnet.ibm.com>
---
 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

