depends on KPROBES && HAVE_OPTPROBES
depends on !PREEMPT
+config KPROBES_ON_FTRACE
+ def_bool y
+ depends on KPROBES && HAVE_KPROBES_ON_FTRACE
+ depends on DYNAMIC_FTRACE_WITH_REGS
+ help
+ If function tracer is enabled and the arch supports full
+ passing of pt_regs to function tracing, then kprobes can
+ optimize on top of function tracing.
+
config UPROBES
bool "Transparent user-space probes (EXPERIMENTAL)"
depends on UPROBE_EVENT && PERF_EVENTS
config HAVE_OPTPROBES
bool
+config HAVE_KPROBES_ON_FTRACE
+ bool
+
config HAVE_NMI_WATCHDOG
bool
#
select HAVE_DMA_CONTIGUOUS if !SWIOTLB
select HAVE_KRETPROBES
select HAVE_OPTPROBES
+ select HAVE_KPROBES_ON_FTRACE
select HAVE_FTRACE_MCOUNT_RECORD
select HAVE_FENTRY if X86_64
select HAVE_C_RECORDMCOUNT
obj-$(CONFIG_CRASH_DUMP) += crash_dump_$(BITS).o
obj-$(CONFIG_KPROBES) += kprobes.o
obj-$(CONFIG_OPTPROBES) += kprobes-opt.o
+obj-$(CONFIG_KPROBES_ON_FTRACE) += kprobes-ftrace.o
obj-$(CONFIG_MODULES) += module.o
obj-$(CONFIG_DOUBLEFAULT) += doublefault_32.o
obj-$(CONFIG_KGDB) += kgdb.o
return addr;
}
#endif
+
+#ifdef CONFIG_KPROBES_ON_FTRACE
+extern int skip_singlestep(struct kprobe *p, struct pt_regs *regs,
+ struct kprobe_ctlblk *kcb);
+#else
+static inline int skip_singlestep(struct kprobe *p, struct pt_regs *regs,
+ struct kprobe_ctlblk *kcb)
+{
+ return 0;
+}
+#endif
#endif
--- /dev/null
+/*
+ * Dynamic Ftrace based Kprobes Optimization
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Copyright (C) Hitachi Ltd., 2012
+ */
+#include <linux/kprobes.h>
+#include <linux/ptrace.h>
+#include <linux/hardirq.h>
+#include <linux/preempt.h>
+#include <linux/ftrace.h>
+
+#include "kprobes-common.h"
+
+static int __skip_singlestep(struct kprobe *p, struct pt_regs *regs,
+ struct kprobe_ctlblk *kcb)
+{
+ /*
+ * Emulate singlestep (and also recover regs->ip)
+ * as if there is a 5byte nop
+ */
+ regs->ip = (unsigned long)p->addr + MCOUNT_INSN_SIZE;
+ if (unlikely(p->post_handler)) {
+ kcb->kprobe_status = KPROBE_HIT_SSDONE;
+ p->post_handler(p, regs, 0);
+ }
+ __this_cpu_write(current_kprobe, NULL);
+ return 1;
+}
+
+int __kprobes skip_singlestep(struct kprobe *p, struct pt_regs *regs,
+ struct kprobe_ctlblk *kcb)
+{
+ if (kprobe_ftrace(p))
+ return __skip_singlestep(p, regs, kcb);
+ else
+ return 0;
+}
+
+/* Ftrace callback handler for kprobes */
+void __kprobes kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_ops *ops, struct pt_regs *regs)
+{
+ struct kprobe *p;
+ struct kprobe_ctlblk *kcb;
+ unsigned long flags;
+
+ /* Disable irq for emulating a breakpoint and avoiding preempt */
+ local_irq_save(flags);
+
+ p = get_kprobe((kprobe_opcode_t *)ip);
+ if (unlikely(!p) || kprobe_disabled(p))
+ goto end;
+
+ kcb = get_kprobe_ctlblk();
+ if (kprobe_running()) {
+ kprobes_inc_nmissed_count(p);
+ } else {
+ /* Kprobe handler expects regs->ip = ip + 1 as breakpoint hit */
+ regs->ip = ip + sizeof(kprobe_opcode_t);
+
+ __this_cpu_write(current_kprobe, p);
+ kcb->kprobe_status = KPROBE_HIT_ACTIVE;
+ if (!p->pre_handler || !p->pre_handler(p, regs))
+ __skip_singlestep(p, regs, kcb);
+ /*
+ * If pre_handler returns !0, it sets regs->ip and
+ * resets current kprobe.
+ */
+ }
+end:
+ local_irq_restore(flags);
+}
+
+int __kprobes arch_prepare_kprobe_ftrace(struct kprobe *p)
+{
+ p->ainsn.insn = NULL;
+ p->ainsn.boostable = -1;
+ return 0;
+}
return 1;
}
-#ifdef KPROBES_CAN_USE_FTRACE
-static void __kprobes skip_singlestep(struct kprobe *p, struct pt_regs *regs,
- struct kprobe_ctlblk *kcb)
-{
- /*
- * Emulate singlestep (and also recover regs->ip)
- * as if there is a 5byte nop
- */
- regs->ip = (unsigned long)p->addr + MCOUNT_INSN_SIZE;
- if (unlikely(p->post_handler)) {
- kcb->kprobe_status = KPROBE_HIT_SSDONE;
- p->post_handler(p, regs, 0);
- }
- __this_cpu_write(current_kprobe, NULL);
-}
-#endif
-
/*
* Interrupts are disabled on entry as trap3 is an interrupt gate and they
* remain disabled throughout this function.
} else if (kprobe_running()) {
p = __this_cpu_read(current_kprobe);
if (p->break_handler && p->break_handler(p, regs)) {
-#ifdef KPROBES_CAN_USE_FTRACE
- if (kprobe_ftrace(p)) {
- skip_singlestep(p, regs, kcb);
- return 1;
- }
-#endif
- setup_singlestep(p, regs, kcb, 0);
+ if (!skip_singlestep(p, regs, kcb))
+ setup_singlestep(p, regs, kcb, 0);
return 1;
}
} /* else: not a kprobe fault; let the kernel handle it */
return 0;
}
-#ifdef KPROBES_CAN_USE_FTRACE
-/* Ftrace callback handler for kprobes */
-void __kprobes kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
- struct ftrace_ops *ops, struct pt_regs *regs)
-{
- struct kprobe *p;
- struct kprobe_ctlblk *kcb;
- unsigned long flags;
-
- /* Disable irq for emulating a breakpoint and avoiding preempt */
- local_irq_save(flags);
-
- p = get_kprobe((kprobe_opcode_t *)ip);
- if (unlikely(!p) || kprobe_disabled(p))
- goto end;
-
- kcb = get_kprobe_ctlblk();
- if (kprobe_running()) {
- kprobes_inc_nmissed_count(p);
- } else {
- /* Kprobe handler expects regs->ip = ip + 1 as breakpoint hit */
- regs->ip = ip + sizeof(kprobe_opcode_t);
-
- __this_cpu_write(current_kprobe, p);
- kcb->kprobe_status = KPROBE_HIT_ACTIVE;
- if (!p->pre_handler || !p->pre_handler(p, regs))
- skip_singlestep(p, regs, kcb);
- /*
- * If pre_handler returns !0, it sets regs->ip and
- * resets current kprobe.
- */
- }
-end:
- local_irq_restore(flags);
-}
-
-int __kprobes arch_prepare_kprobe_ftrace(struct kprobe *p)
-{
- p->ainsn.insn = NULL;
- p->ainsn.boostable = -1;
- return 0;
-}
-#endif
-
int __init arch_init_kprobes(void)
{
return arch_init_optprobes();
#define KPROBE_REENTER 0x00000004
#define KPROBE_HIT_SSDONE 0x00000008
-/*
- * If function tracer is enabled and the arch supports full
- * passing of pt_regs to function tracing, then kprobes can
- * optimize on top of function tracing.
- */
-#if defined(CONFIG_FUNCTION_TRACER) && defined(ARCH_SUPPORTS_FTRACE_SAVE_REGS) \
- && defined(ARCH_SUPPORTS_KPROBES_ON_FTRACE)
-# define KPROBES_CAN_USE_FTRACE
-#endif
-
/* Attach to insert probes on any functions which should be ignored*/
#define __kprobes __attribute__((__section__(".kprobes.text")))
#endif
#endif /* CONFIG_OPTPROBES */
-#ifdef KPROBES_CAN_USE_FTRACE
+#ifdef CONFIG_KPROBES_ON_FTRACE
extern void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
struct ftrace_ops *ops, struct pt_regs *regs);
extern int arch_prepare_kprobe_ftrace(struct kprobe *p);
}
#endif /* CONFIG_OPTPROBES */
-#ifdef KPROBES_CAN_USE_FTRACE
+#ifdef CONFIG_KPROBES_ON_FTRACE
static struct ftrace_ops kprobe_ftrace_ops __read_mostly = {
.func = kprobe_ftrace_handler,
.flags = FTRACE_OPS_FL_SAVE_REGS,
(unsigned long)p->addr, 1, 0);
WARN(ret < 0, "Failed to disarm kprobe-ftrace at %p (%d)\n", p->addr, ret);
}
-#else /* !KPROBES_CAN_USE_FTRACE */
+#else /* !CONFIG_KPROBES_ON_FTRACE */
#define prepare_kprobe(p) arch_prepare_kprobe(p)
#define arm_kprobe_ftrace(p) do {} while (0)
#define disarm_kprobe_ftrace(p) do {} while (0)
*/
ftrace_addr = ftrace_location((unsigned long)p->addr);
if (ftrace_addr) {
-#ifdef KPROBES_CAN_USE_FTRACE
+#ifdef CONFIG_KPROBES_ON_FTRACE
/* Given address is not on the instruction boundary */
if ((unsigned long)p->addr != ftrace_addr)
return -EILSEQ;
p->flags |= KPROBE_FLAG_FTRACE;
-#else /* !KPROBES_CAN_USE_FTRACE */
+#else /* !CONFIG_KPROBES_ON_FTRACE */
return -EINVAL;
#endif
}
projects / linux-2.6-microblaze.git / commitdiff