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kprobes/x86: Make boostable flag boolean

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Make arch_specific_insn.boostable to boolean, since it has
only 2 states, boostable or not. So it is better to use
boolean from the viewpoint of code readability.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David S . Miller <davem@davemloft.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ye Xiaolong <xiaolong.ye@intel.com>
Link: http://lkml.kernel.org/r/149076368566.22469.6322906866458231844.stgit@devbox
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Masami Hiramatsu 2017-03-29 14:01:35 +09:00 committed by Ingo Molnar
parent 804dec5bda
commit 490154bc68
3 changed files with 10 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
arch/x86/include/asm/kprobes.h
View File

@ -72,14 +72,13 @@ struct arch_specific_insn {
/* copy of the original instruction */ /* copy of the original instruction */
kprobe_opcode_t *insn; kprobe_opcode_t *insn;
/* /*
* boostable = -1: This instruction type is not boostable. * boostable = false: This instruction type is not boostable.
* boostable = 0: This instruction type is boostable. * boostable = true: This instruction has been boosted: we have
* boostable = 1: This instruction has been boosted: we have
* added a relative jump after the instruction copy in insn, * added a relative jump after the instruction copy in insn,
* so no single-step and fixup are needed (unless there's * so no single-step and fixup are needed (unless there's
* a post_handler or break_handler). * a post_handler or break_handler).
*/ */
int boostable; bool boostable;
bool if_modifier; bool if_modifier;
}; };

12
arch/x86/kernel/kprobes/core.c
View File

@ -409,9 +409,9 @@ static void prepare_boost(struct kprobe *p, int length)
* jumps back to correct address. * jumps back to correct address.
*/ */
synthesize_reljump(p->ainsn.insn + length, p->addr + length); synthesize_reljump(p->ainsn.insn + length, p->addr + length);
p->ainsn.boostable = 1; p->ainsn.boostable = true;
} else { } else {
p->ainsn.boostable = -1; p->ainsn.boostable = false;
} }
} }
@ -467,7 +467,7 @@ void arch_disarm_kprobe(struct kprobe *p)
void arch_remove_kprobe(struct kprobe *p) void arch_remove_kprobe(struct kprobe *p)
{ {
if (p->ainsn.insn) { if (p->ainsn.insn) {
free_insn_slot(p->ainsn.insn, (p->ainsn.boostable == 1)); free_insn_slot(p->ainsn.insn, p->ainsn.boostable);
p->ainsn.insn = NULL; p->ainsn.insn = NULL;
} }
} }
@ -539,7 +539,7 @@ static void setup_singlestep(struct kprobe *p, struct pt_regs *regs,
return; return;
#if !defined(CONFIG_PREEMPT) #if !defined(CONFIG_PREEMPT)
if (p->ainsn.boostable == 1 && !p->post_handler) { if (p->ainsn.boostable && !p->post_handler) {
/* Boost up -- we can execute copied instructions directly */ /* Boost up -- we can execute copied instructions directly */
if (!reenter) if (!reenter)
reset_current_kprobe(); reset_current_kprobe();
@ -859,7 +859,7 @@ static void resume_execution(struct kprobe *p, struct pt_regs *regs,
case 0xcf: case 0xcf:
case 0xea: /* jmp absolute -- ip is correct */ case 0xea: /* jmp absolute -- ip is correct */
/* ip is already adjusted, no more changes required */ /* ip is already adjusted, no more changes required */
p->ainsn.boostable = 1; p->ainsn.boostable = true;
goto no_change; goto no_change;
case 0xe8: /* call relative - Fix return addr */ case 0xe8: /* call relative - Fix return addr */
*tos = orig_ip + (*tos - copy_ip); *tos = orig_ip + (*tos - copy_ip);
@ -884,7 +884,7 @@ static void resume_execution(struct kprobe *p, struct pt_regs *regs,
* jmp near and far, absolute indirect * jmp near and far, absolute indirect
* ip is correct. And this is boostable * ip is correct. And this is boostable
*/ */
p->ainsn.boostable = 1; p->ainsn.boostable = true;
goto no_change; goto no_change;
} }
default: default:

2
arch/x86/kernel/kprobes/ftrace.c
View File

@ -94,6 +94,6 @@ NOKPROBE_SYMBOL(kprobe_ftrace_handler);
int arch_prepare_kprobe_ftrace(struct kprobe *p) int arch_prepare_kprobe_ftrace(struct kprobe *p)
{ {
p->ainsn.insn = NULL; p->ainsn.insn = NULL;
p->ainsn.boostable = -1; p->ainsn.boostable = false;
return 0; return 0;
} }