Subject: [PATCH v7 10/28] powerpc: Introduce functions for instruction equality

From: Jordan Niethe <[email-masked]>
Date: Fri, 1 May 2020 13:42:02 +1000

In preparation for an instruction data type that can not be directly
used with the '==' operator use functions for checking equality.

Reviewed-by: Balamuruhan S <[email-masked]>
Signed-off-by: Jordan Niethe <[email-masked]>
---
v5: Remove ppc_inst_null()
v7: Fix compilation issue in expected_nop_sequence() when no
    CONFIG_MPROFILE_KERNEL
---
 arch/powerpc/include/asm/inst.h    |  5 +++++
 arch/powerpc/kernel/trace/ftrace.c | 15 ++++++++-------
 arch/powerpc/lib/code-patching.c   | 12 ++++++------
 arch/powerpc/xmon/xmon.c           |  4 ++--
 4 files changed, 21 insertions(+), 15 deletions(-)

diff --git a/arch/powerpc/include/asm/inst.h b/arch/powerpc/include/asm/inst.h
index 23fd57a86b03..0c5dc539160a 100644
--- a/arch/powerpc/include/asm/inst.h
+++ b/arch/powerpc/include/asm/inst.h
@@ -23,4 +23,9 @@ static inline u32 ppc_inst_swab(u32 x)
 	return ppc_inst(swab32(ppc_inst_val(x)));
 }
 
+static inline bool ppc_inst_equal(u32 x, u32 y)
+{
+	return x == y;
+}
+
 #endif /* _ASM_INST_H */
diff --git a/arch/powerpc/kernel/trace/ftrace.c b/arch/powerpc/kernel/trace/ftrace.c
index 335b10008035..d83c1be417f2 100644
--- a/arch/powerpc/kernel/trace/ftrace.c
+++ b/arch/powerpc/kernel/trace/ftrace.c
@@ -72,7 +72,7 @@ ftrace_modify_code(unsigned long ip, unsigned int old, unsigned int new)
 		return -EFAULT;
 
 	/* Make sure it is what we expect it to be */
-	if (replaced != old) {
+	if (!ppc_inst_equal(replaced, old)) {
 		pr_err("%p: replaced (%#x) != old (%#x)",
 		(void *)ip, ppc_inst_val(replaced), ppc_inst_val(old));
 		return -EINVAL;
@@ -170,7 +170,8 @@ __ftrace_make_nop(struct module *mod,
 	}
 
 	/* We expect either a mflr r0, or a std r0, LRSAVE(r1) */
-	if (op != ppc_inst(PPC_INST_MFLR) && op != ppc_inst(PPC_INST_STD_LR)) {
+	if (!ppc_inst_equal(op, ppc_inst(PPC_INST_MFLR)) &&
+	    !ppc_inst_equal(op, ppc_inst(PPC_INST_STD_LR))) {
 		pr_err("Unexpected instruction %08x around bl _mcount\n", ppc_inst_val(op));
 		return -EINVAL;
 	}
@@ -200,7 +201,7 @@ __ftrace_make_nop(struct module *mod,
 		return -EFAULT;
 	}
 
-	if (op != ppc_inst(PPC_INST_LD_TOC)) {
+	if (!ppc_inst_equal(op,  ppc_inst(PPC_INST_LD_TOC))) {
 		pr_err("Expected %08x found %08x\n", PPC_INST_LD_TOC, ppc_inst_val(op));
 		return -EINVAL;
 	}
@@ -497,7 +498,7 @@ expected_nop_sequence(void *ip, unsigned int op0, unsigned int op1)
 	 * The load offset is different depending on the ABI. For simplicity
 	 * just mask it out when doing the compare.
 	 */
-	if ((op0 != ppc_inst(0x48000008)) || (ppc_inst_val(op1) & 0xffff0000) != 0xe8410000)
+	if ((!ppc_inst_equal(op0, ppc_inst(0x48000008))) || (ppc_inst_val(op1) & 0xffff0000) != 0xe8410000)
 		return 0;
 	return 1;
 }
@@ -506,7 +507,7 @@ static int
 expected_nop_sequence(void *ip, unsigned int op0, unsigned int op1)
 {
 	/* look for patched "NOP" on ppc64 with -mprofile-kernel */
-	if (op0 != ppc_inst(PPC_INST_NOP))
+	if (!ppc_inst_equal(op0, ppc_inst(PPC_INST_NOP)))
 		return 0;
 	return 1;
 }
@@ -589,7 +590,7 @@ __ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
 		return -EFAULT;
 
 	/* It should be pointing to a nop */
-	if (op != ppc_inst(PPC_INST_NOP)) {
+	if (!ppc_inst_equal(op,  ppc_inst(PPC_INST_NOP))) {
 		pr_err("Expected NOP but have %x\n", op);
 		return -EINVAL;
 	}
@@ -646,7 +647,7 @@ static int __ftrace_make_call_kernel(struct dyn_ftrace *rec, unsigned long addr)
 		return -EFAULT;
 	}
 
-	if (op != ppc_inst(PPC_INST_NOP)) {
+	if (!ppc_inst_equal(op, ppc_inst(PPC_INST_NOP))) {
 		pr_err("Unexpected call sequence at %p: %x\n", ip, ppc_inst_val(op));
 		return -EINVAL;
 	}
diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c
index f5c6dcbac44b..d298bb16936e 100644
--- a/arch/powerpc/lib/code-patching.c
+++ b/arch/powerpc/lib/code-patching.c
@@ -479,7 +479,7 @@ static void __init test_branch_iform(void)
 	/* Check flags are masked correctly */
 	err = create_branch(&instr, &instr, addr, 0xFFFFFFFC);
 	check(instr_is_branch_to_addr(&instr, addr));
-	check(instr == ppc_inst(0x48000000));
+	check(ppc_inst_equal(instr, ppc_inst(0x48000000)));
 }
 
 static void __init test_create_function_call(void)
@@ -564,7 +564,7 @@ static void __init test_branch_bform(void)
 	/* Check flags are masked correctly */
 	err = create_cond_branch(&instr, iptr, addr, 0xFFFFFFFC);
 	check(instr_is_branch_to_addr(&instr, addr));
-	check(instr == ppc_inst(0x43FF0000));
+	check(ppc_inst_equal(instr, ppc_inst(0x43FF0000)));
 }
 
 static void __init test_translate_branch(void)
@@ -598,7 +598,7 @@ static void __init test_translate_branch(void)
 	patch_instruction(q, instr);
 	check(instr_is_branch_to_addr(p, addr));
 	check(instr_is_branch_to_addr(q, addr));
-	check(*q == ppc_inst(0x4a000000));
+	check(ppc_inst_equal(*q, ppc_inst(0x4a000000)));
 
 	/* Maximum positive case, move x to x - 32 MB + 4 */
 	p = buf + 0x2000000;
@@ -609,7 +609,7 @@ static void __init test_translate_branch(void)
 	patch_instruction(q, instr);
 	check(instr_is_branch_to_addr(p, addr));
 	check(instr_is_branch_to_addr(q, addr));
-	check(*q == ppc_inst(0x49fffffc));
+	check(ppc_inst_equal(*q, ppc_inst(0x49fffffc)));
 
 	/* Jump to x + 16 MB moved to x + 20 MB */
 	p = buf;
@@ -655,7 +655,7 @@ static void __init test_translate_branch(void)
 	patch_instruction(q, instr);
 	check(instr_is_branch_to_addr(p, addr));
 	check(instr_is_branch_to_addr(q, addr));
-	check(*q == ppc_inst(0x43ff8000));
+	check(ppc_inst_equal(*q, ppc_inst(0x43ff8000)));
 
 	/* Maximum positive case, move x to x - 32 KB + 4 */
 	p = buf + 0x8000;
@@ -667,7 +667,7 @@ static void __init test_translate_branch(void)
 	patch_instruction(q, instr);
 	check(instr_is_branch_to_addr(p, addr));
 	check(instr_is_branch_to_addr(q, addr));
-	check(*q == ppc_inst(0x43ff7ffc));
+	check(ppc_inst_equal(*q, ppc_inst(0x43ff7ffc)));
 
 	/* Jump to x + 12 KB moved to x + 20 KB */
 	p = buf;
diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c
index 855676785c56..5064e29a3dab 100644
--- a/arch/powerpc/xmon/xmon.c
+++ b/arch/powerpc/xmon/xmon.c
@@ -947,7 +947,7 @@ static void remove_bpts(void)
 		if ((bp->enabled & (BP_TRAP|BP_CIABR)) != BP_TRAP)
 			continue;
 		if (mread(bp->address, &instr, 4) == 4
-		    && instr == ppc_inst(bpinstr)
+		    && ppc_inst_equal(instr, ppc_inst(bpinstr))
 		    && patch_instruction(
 			(unsigned int *)bp->address, bp->instr[0]) != 0)
 			printf("Couldn't remove breakpoint at %lx\n",
@@ -2862,7 +2862,7 @@ generic_inst_dump(unsigned long adr, long count, int praddr,
 			break;
 		}
 		inst = ppc_inst(GETWORD(val));
-		if (adr > first_adr && inst == last_inst) {
+		if (adr > first_adr && ppc_inst_equal(inst, last_inst)) {
 			if (!dotted) {
 				printf(" ...\n");
 				dotted = 1;
-- 
2.17.1