From: Ananth N Mavinakayanahalli <[email protected]>
IA64 changes to track kprobe execution on a per-cpu basis. We now track
the kprobe state machine independently on each cpu using an arch specific
kprobe control block.
Signed-off-by: Ananth N Mavinakayanahalli <[email protected]>
Signed-off-by: Anil S Keshavamurthy <[email protected]>
---
arch/ia64/kernel/kprobes.c | 83 ++++++++++++++++++++++++---------------------
include/asm-ia64/kprobes.h | 13 +++++++
2 files changed, 58 insertions(+), 38 deletions(-)
Index: linux-2.6.14-rc3/arch/ia64/kernel/kprobes.c
===================================================================
--- linux-2.6.14-rc3.orig/arch/ia64/kernel/kprobes.c 2005-10-05 15:23:17.000000000 -0400
+++ linux-2.6.14-rc3/arch/ia64/kernel/kprobes.c 2005-10-05 15:29:28.000000000 -0400
@@ -38,13 +38,8 @@
extern void jprobe_inst_return(void);
-/* kprobe_status settings */
-#define KPROBE_HIT_ACTIVE 0x00000001
-#define KPROBE_HIT_SS 0x00000002
-
-static struct kprobe *current_kprobe, *kprobe_prev;
-static unsigned long kprobe_status, kprobe_status_prev;
-static struct pt_regs jprobe_saved_regs;
+DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
+DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
enum instruction_type {A, I, M, F, B, L, X, u};
static enum instruction_type bundle_encoding[32][3] = {
@@ -313,21 +308,22 @@ static int __kprobes valid_kprobe_addr(i
return 0;
}
-static inline void save_previous_kprobe(void)
+static inline void save_previous_kprobe(struct kprobe_ctlblk *kcb)
{
- kprobe_prev = current_kprobe;
- kprobe_status_prev = kprobe_status;
+ kcb->prev_kprobe.kp = kprobe_running();
+ kcb->prev_kprobe.status = kcb->kprobe_status;
}
-static inline void restore_previous_kprobe(void)
+static inline void restore_previous_kprobe(struct kprobe_ctlblk *kcb)
{
- current_kprobe = kprobe_prev;
- kprobe_status = kprobe_status_prev;
+ __get_cpu_var(current_kprobe) = kcb->prev_kprobe.kp;
+ kcb->kprobe_status = kcb->prev_kprobe.status;
}
-static inline void set_current_kprobe(struct kprobe *p)
+static inline void set_current_kprobe(struct kprobe *p,
+ struct kprobe_ctlblk *kcb)
{
- current_kprobe = p;
+ __get_cpu_var(current_kprobe) = p;
}
static void kretprobe_trampoline(void)
@@ -389,6 +385,7 @@ int __kprobes trampoline_probe_handler(s
BUG_ON(!orig_ret_address || (orig_ret_address == trampoline_address));
regs->cr_iip = orig_ret_address;
+ reset_current_kprobe();
unlock_kprobes();
preempt_enable_no_resched();
@@ -606,12 +603,13 @@ static int __kprobes pre_kprobes_handler
int ret = 0;
struct pt_regs *regs = args->regs;
kprobe_opcode_t *addr = (kprobe_opcode_t *)instruction_pointer(regs);
+ struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
/* Handle recursion cases */
if (kprobe_running()) {
p = get_kprobe(addr);
if (p) {
- if ( (kprobe_status == KPROBE_HIT_SS) &&
+ if ((kcb->kprobe_status == KPROBE_HIT_SS) &&
(p->ainsn.inst_flag == INST_FLAG_BREAK_INST)) {
ia64_psr(regs)->ss = 0;
unlock_kprobes();
@@ -623,17 +621,17 @@ static int __kprobes pre_kprobes_handler
* just single step on the instruction of the new probe
* without calling any user handlers.
*/
- save_previous_kprobe();
- set_current_kprobe(p);
+ save_previous_kprobe(kcb);
+ set_current_kprobe(p, kcb);
p->nmissed++;
prepare_ss(p, regs);
- kprobe_status = KPROBE_REENTER;
+ kcb->kprobe_status = KPROBE_REENTER;
return 1;
} else if (args->err == __IA64_BREAK_JPROBE) {
/*
* jprobe instrumented function just completed
*/
- p = current_kprobe;
+ p = __get_cpu_var(current_kprobe);
if (p->break_handler && p->break_handler(p, regs)) {
goto ss_probe;
}
@@ -668,8 +666,8 @@ static int __kprobes pre_kprobes_handler
* in post_kprobes_handler()
*/
preempt_disable();
- kprobe_status = KPROBE_HIT_ACTIVE;
- set_current_kprobe(p);
+ set_current_kprobe(p, kcb);
+ kcb->kprobe_status = KPROBE_HIT_ACTIVE;
if (p->pre_handler && p->pre_handler(p, regs))
/*
@@ -681,7 +679,7 @@ static int __kprobes pre_kprobes_handler
ss_probe:
prepare_ss(p, regs);
- kprobe_status = KPROBE_HIT_SS;
+ kcb->kprobe_status = KPROBE_HIT_SS;
return 1;
no_kprobe:
@@ -690,22 +688,25 @@ no_kprobe:
static int __kprobes post_kprobes_handler(struct pt_regs *regs)
{
- if (!kprobe_running())
+ struct kprobe *cur = kprobe_running();
+ struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
+
+ if (!cur)
return 0;
- if ((kprobe_status != KPROBE_REENTER) && current_kprobe->post_handler) {
- kprobe_status = KPROBE_HIT_SSDONE;
- current_kprobe->post_handler(current_kprobe, regs, 0);
+ if ((kcb->kprobe_status != KPROBE_REENTER) && cur->post_handler) {
+ kcb->kprobe_status = KPROBE_HIT_SSDONE;
+ cur->post_handler(cur, regs, 0);
}
- resume_execution(current_kprobe, regs);
+ resume_execution(cur, regs);
/*Restore back the original saved kprobes variables and continue. */
- if (kprobe_status == KPROBE_REENTER) {
- restore_previous_kprobe();
+ if (kcb->kprobe_status == KPROBE_REENTER) {
+ restore_previous_kprobe(kcb);
goto out;
}
-
+ reset_current_kprobe();
unlock_kprobes();
out:
@@ -715,15 +716,18 @@ out:
static int __kprobes kprobes_fault_handler(struct pt_regs *regs, int trapnr)
{
- if (!kprobe_running())
+ struct kprobe *cur = kprobe_running();
+ struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
+
+ if (!cur)
return 0;
- if (current_kprobe->fault_handler &&
- current_kprobe->fault_handler(current_kprobe, regs, trapnr))
+ if (cur->fault_handler && cur->fault_handler(cur, regs, trapnr))
return 1;
- if (kprobe_status & KPROBE_HIT_SS) {
- resume_execution(current_kprobe, regs);
+ if (kcb->kprobe_status & KPROBE_HIT_SS) {
+ resume_execution(cur, regs);
+ reset_current_kprobe();
unlock_kprobes();
preempt_enable_no_resched();
}
@@ -761,9 +765,10 @@ int __kprobes setjmp_pre_handler(struct
{
struct jprobe *jp = container_of(p, struct jprobe, kp);
unsigned long addr = ((struct fnptr *)(jp->entry))->ip;
+ struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
/* save architectural state */
- jprobe_saved_regs = *regs;
+ kcb->jprobe_saved_regs = *regs;
/* after rfi, execute the jprobe instrumented function */
regs->cr_iip = addr & ~0xFULL;
@@ -781,7 +786,9 @@ int __kprobes setjmp_pre_handler(struct
int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
{
- *regs = jprobe_saved_regs;
+ struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
+
+ *regs = kcb->jprobe_saved_regs;
return 1;
}
Index: linux-2.6.14-rc3/include/asm-ia64/kprobes.h
===================================================================
--- linux-2.6.14-rc3.orig/include/asm-ia64/kprobes.h 2005-09-30 17:17:35.000000000 -0400
+++ linux-2.6.14-rc3/include/asm-ia64/kprobes.h 2005-10-05 15:28:35.000000000 -0400
@@ -26,6 +26,7 @@
*/
#include <linux/types.h>
#include <linux/ptrace.h>
+#include <linux/percpu.h>
#include <asm/break.h>
#define MAX_INSN_SIZE 16
@@ -62,6 +63,18 @@ typedef struct _bundle {
} quad1;
} __attribute__((__aligned__(16))) bundle_t;
+struct prev_kprobe {
+ struct kprobe *kp;
+ unsigned long status;
+};
+
+/* per-cpu kprobe control block */
+struct kprobe_ctlblk {
+ unsigned long kprobe_status;
+ struct pt_regs jprobe_saved_regs;
+ struct prev_kprobe prev_kprobe;
+};
+
#define JPROBE_ENTRY(pentry) (kprobe_opcode_t *)pentry
#define ARCH_SUPPORTS_KRETPROBES
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
