Commit afd3287c authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman

powerpc/optprobes: Minimise casts

nip is already an unsigned long, no cast needed.

op_callback_addr and emulate_step_addr are kprobe_opcode_t *.
There value is obtained with ppc_kallsyms_lookup_name() which
returns 'unsigned long', and there values are used create_branch()
which expects 'unsigned long'. So change them to 'unsigned long'
to avoid casting them back and forth.

can_optimize() used p->addr several times as 'unsigned long'.
Use a local 'unsigned long' variable and avoid casting multiple times.
Signed-off-by: default avatarChristophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/e03192a6d4123242a275e71ce2ba0bb4d90700c1.1621516826.git.christophe.leroy@csgroup.eu
parent 077c4ded
......@@ -55,6 +55,7 @@ static unsigned long can_optimize(struct kprobe *p)
struct pt_regs regs;
struct instruction_op op;
unsigned long nip = 0;
unsigned long addr = (unsigned long)p->addr;
/*
* kprobe placed for kretprobe during boot time
......@@ -62,7 +63,7 @@ static unsigned long can_optimize(struct kprobe *p)
* So further checks can be skipped.
*/
if (p->addr == (kprobe_opcode_t *)&kretprobe_trampoline)
return (unsigned long)p->addr + sizeof(kprobe_opcode_t);
return addr + sizeof(kprobe_opcode_t);
/*
* We only support optimizing kernel addresses, but not
......@@ -70,11 +71,11 @@ static unsigned long can_optimize(struct kprobe *p)
*
* FIXME: Optimize kprobes placed in module addresses.
*/
if (!is_kernel_addr((unsigned long)p->addr))
if (!is_kernel_addr(addr))
return 0;
memset(&regs, 0, sizeof(struct pt_regs));
regs.nip = (unsigned long)p->addr;
regs.nip = addr;
regs.trap = 0x0;
regs.msr = MSR_KERNEL;
......@@ -184,7 +185,8 @@ static void patch_imm_load_insns(unsigned long val, int reg, kprobe_opcode_t *ad
int arch_prepare_optimized_kprobe(struct optimized_kprobe *op, struct kprobe *p)
{
struct ppc_inst branch_op_callback, branch_emulate_step, temp;
kprobe_opcode_t *op_callback_addr, *emulate_step_addr, *buff;
unsigned long op_callback_addr, emulate_step_addr;
kprobe_opcode_t *buff;
long b_offset;
unsigned long nip, size;
int rc, i;
......@@ -212,8 +214,7 @@ int arch_prepare_optimized_kprobe(struct optimized_kprobe *op, struct kprobe *p)
goto error;
/* Check if the return address is also within 32MB range */
b_offset = (unsigned long)(buff + TMPL_RET_IDX) -
(unsigned long)nip;
b_offset = (unsigned long)(buff + TMPL_RET_IDX) - nip;
if (!is_offset_in_branch_range(b_offset))
goto error;
......@@ -236,20 +237,18 @@ int arch_prepare_optimized_kprobe(struct optimized_kprobe *op, struct kprobe *p)
/*
* 2. branch to optimized_callback() and emulate_step()
*/
op_callback_addr = (kprobe_opcode_t *)ppc_kallsyms_lookup_name("optimized_callback");
emulate_step_addr = (kprobe_opcode_t *)ppc_kallsyms_lookup_name("emulate_step");
op_callback_addr = ppc_kallsyms_lookup_name("optimized_callback");
emulate_step_addr = ppc_kallsyms_lookup_name("emulate_step");
if (!op_callback_addr || !emulate_step_addr) {
WARN(1, "Unable to lookup optimized_callback()/emulate_step()\n");
goto error;
}
rc = create_branch(&branch_op_callback, buff + TMPL_CALL_HDLR_IDX,
(unsigned long)op_callback_addr,
BRANCH_SET_LINK);
op_callback_addr, BRANCH_SET_LINK);
rc |= create_branch(&branch_emulate_step, buff + TMPL_EMULATE_IDX,
(unsigned long)emulate_step_addr,
BRANCH_SET_LINK);
emulate_step_addr, BRANCH_SET_LINK);
if (rc)
goto error;
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment