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-rw-r--r--include/linux/hw_breakpoint.h35
-rw-r--r--kernel/hw_breakpoint.c35
-rw-r--r--kernel/trace/trace_ksym.c42
-rw-r--r--samples/hw_breakpoint/data_breakpoint.c10
4 files changed, 44 insertions, 78 deletions
diff --git a/include/linux/hw_breakpoint.h b/include/linux/hw_breakpoint.h
index 5da472e..a03daed 100644
--- a/include/linux/hw_breakpoint.h
+++ b/include/linux/hw_breakpoint.h
@@ -28,6 +28,13 @@ struct perf_event_attr name = { \
.pinned = 1, \
};
+static inline void hw_breakpoint_init(struct perf_event_attr *attr)
+{
+ attr->type = PERF_TYPE_BREAKPOINT;
+ attr->size = sizeof(*attr);
+ attr->pinned = 1;
+}
+
static inline unsigned long hw_breakpoint_addr(struct perf_event *bp)
{
return bp->attr.bp_addr;
@@ -59,19 +66,13 @@ modify_user_hw_breakpoint(struct perf_event *bp,
* Kernel breakpoints are not associated with any particular thread.
*/
extern struct perf_event *
-register_wide_hw_breakpoint_cpu(unsigned long addr,
- int len,
- int type,
+register_wide_hw_breakpoint_cpu(struct perf_event_attr *attr,
perf_callback_t triggered,
- int cpu,
- bool active);
+ int cpu);
extern struct perf_event **
-register_wide_hw_breakpoint(unsigned long addr,
- int len,
- int type,
- perf_callback_t triggered,
- bool active);
+register_wide_hw_breakpoint(struct perf_event_attr *attr,
+ perf_callback_t triggered);
extern int register_perf_hw_breakpoint(struct perf_event *bp);
extern int __register_perf_hw_breakpoint(struct perf_event *bp);
@@ -100,18 +101,12 @@ modify_user_hw_breakpoint(struct perf_event *bp,
perf_callback_t triggered,
struct task_struct *tsk) { return NULL; }
static inline struct perf_event *
-register_wide_hw_breakpoint_cpu(unsigned long addr,
- int len,
- int type,
+register_wide_hw_breakpoint_cpu(struct perf_event_attr *attr,
perf_callback_t triggered,
- int cpu,
- bool active) { return NULL; }
+ int cpu) { return NULL; }
static inline struct perf_event **
-register_wide_hw_breakpoint(unsigned long addr,
- int len,
- int type,
- perf_callback_t triggered,
- bool active) { return NULL; }
+register_wide_hw_breakpoint(struct perf_event_attr *attr,
+ perf_callback_t triggered) { return NULL; }
static inline int
register_perf_hw_breakpoint(struct perf_event *bp) { return -ENOSYS; }
static inline int
diff --git a/kernel/hw_breakpoint.c b/kernel/hw_breakpoint.c
index 2a47514..cf5ee16 100644
--- a/kernel/hw_breakpoint.c
+++ b/kernel/hw_breakpoint.c
@@ -339,42 +339,16 @@ void unregister_hw_breakpoint(struct perf_event *bp)
}
EXPORT_SYMBOL_GPL(unregister_hw_breakpoint);
-static struct perf_event *
-register_kernel_hw_breakpoint_cpu(unsigned long addr,
- int len,
- int type,
- perf_callback_t triggered,
- int cpu,
- bool active)
-{
- DEFINE_BREAKPOINT_ATTR(attr);
-
- attr.bp_addr = addr;
- attr.bp_len = len;
- attr.bp_type = type;
-
- if (!active)
- attr.disabled = 1;
-
- return perf_event_create_kernel_counter(&attr, cpu, -1, triggered);
-}
-
/**
* register_wide_hw_breakpoint - register a wide breakpoint in the kernel
- * @addr: is the memory address that triggers the breakpoint
- * @len: the length of the access to the memory (1 byte, 2 bytes etc...)
- * @type: the type of the access to the memory (read/write/exec)
+ * @attr: breakpoint attributes
* @triggered: callback to trigger when we hit the breakpoint
- * @active: should we activate it while registering it
*
* @return a set of per_cpu pointers to perf events
*/
struct perf_event **
-register_wide_hw_breakpoint(unsigned long addr,
- int len,
- int type,
- perf_callback_t triggered,
- bool active)
+register_wide_hw_breakpoint(struct perf_event_attr *attr,
+ perf_callback_t triggered)
{
struct perf_event **cpu_events, **pevent, *bp;
long err;
@@ -386,8 +360,7 @@ register_wide_hw_breakpoint(unsigned long addr,
for_each_possible_cpu(cpu) {
pevent = per_cpu_ptr(cpu_events, cpu);
- bp = register_kernel_hw_breakpoint_cpu(addr, len, type,
- triggered, cpu, active);
+ bp = perf_event_create_kernel_counter(attr, cpu, -1, triggered);
*pevent = bp;
diff --git a/kernel/trace/trace_ksym.c b/kernel/trace/trace_ksym.c
index c538b15..ddfa0fd 100644
--- a/kernel/trace/trace_ksym.c
+++ b/kernel/trace/trace_ksym.c
@@ -42,9 +42,7 @@
struct trace_ksym {
struct perf_event **ksym_hbp;
- unsigned long ksym_addr;
- int type;
- int len;
+ struct perf_event_attr attr;
#ifdef CONFIG_PROFILE_KSYM_TRACER
unsigned long counter;
#endif
@@ -71,7 +69,7 @@ void ksym_collect_stats(unsigned long hbp_hit_addr)
rcu_read_lock();
hlist_for_each_entry_rcu(entry, node, &ksym_filter_head, ksym_hlist) {
- if ((entry->ksym_addr == hbp_hit_addr) &&
+ if ((entry->attr.bp_addr == hbp_hit_addr) &&
(entry->counter <= MAX_UL_INT)) {
entry->counter++;
break;
@@ -192,14 +190,15 @@ int process_new_ksym_entry(char *ksymname, int op, unsigned long addr)
if (!entry)
return -ENOMEM;
- entry->type = op;
- entry->ksym_addr = addr;
- entry->len = HW_BREAKPOINT_LEN_4;
+ hw_breakpoint_init(&entry->attr);
+
+ entry->attr.bp_type = op;
+ entry->attr.bp_addr = addr;
+ entry->attr.bp_len = HW_BREAKPOINT_LEN_4;
ret = -EAGAIN;
- entry->ksym_hbp = register_wide_hw_breakpoint(entry->ksym_addr,
- entry->len, entry->type,
- ksym_hbp_handler, true);
+ entry->ksym_hbp = register_wide_hw_breakpoint(&entry->attr,
+ ksym_hbp_handler);
if (IS_ERR(entry->ksym_hbp)) {
ret = PTR_ERR(entry->ksym_hbp);
@@ -236,12 +235,12 @@ static ssize_t ksym_trace_filter_read(struct file *filp, char __user *ubuf,
mutex_lock(&ksym_tracer_mutex);
hlist_for_each_entry(entry, node, &ksym_filter_head, ksym_hlist) {
- ret = trace_seq_printf(s, "%pS:", (void *)entry->ksym_addr);
- if (entry->type == HW_BREAKPOINT_R)
+ ret = trace_seq_printf(s, "%pS:", (void *)entry->attr.bp_addr);
+ if (entry->attr.bp_type == HW_BREAKPOINT_R)
ret = trace_seq_puts(s, "r--\n");
- else if (entry->type == HW_BREAKPOINT_W)
+ else if (entry->attr.bp_type == HW_BREAKPOINT_W)
ret = trace_seq_puts(s, "-w-\n");
- else if (entry->type == (HW_BREAKPOINT_W | HW_BREAKPOINT_R))
+ else if (entry->attr.bp_type == (HW_BREAKPOINT_W | HW_BREAKPOINT_R))
ret = trace_seq_puts(s, "rw-\n");
WARN_ON_ONCE(!ret);
}
@@ -317,9 +316,9 @@ static ssize_t ksym_trace_filter_write(struct file *file,
ret = -EINVAL;
hlist_for_each_entry(entry, node, &ksym_filter_head, ksym_hlist) {
- if (entry->ksym_addr == ksym_addr) {
+ if (entry->attr.bp_addr == ksym_addr) {
/* Check for malformed request: (6) */
- if (entry->type != op)
+ if (entry->attr.bp_type != op)
changed = 1;
else
goto out;
@@ -328,13 +327,12 @@ static ssize_t ksym_trace_filter_write(struct file *file,
}
if (changed) {
unregister_wide_hw_breakpoint(entry->ksym_hbp);
- entry->type = op;
+ entry->attr.bp_type = op;
ret = 0;
if (op > 0) {
entry->ksym_hbp =
- register_wide_hw_breakpoint(entry->ksym_addr,
- entry->len, entry->type,
- ksym_hbp_handler, true);
+ register_wide_hw_breakpoint(&entry->attr,
+ ksym_hbp_handler);
if (IS_ERR(entry->ksym_hbp))
ret = PTR_ERR(entry->ksym_hbp);
else
@@ -489,7 +487,7 @@ static int ksym_tracer_stat_show(struct seq_file *m, void *v)
entry = hlist_entry(stat, struct trace_ksym, ksym_hlist);
- access_type = entry->type;
+ access_type = entry->attr.bp_type;
switch (access_type) {
case HW_BREAKPOINT_R:
@@ -505,7 +503,7 @@ static int ksym_tracer_stat_show(struct seq_file *m, void *v)
seq_puts(m, " NA ");
}
- if (lookup_symbol_name(entry->ksym_addr, fn_name) >= 0)
+ if (lookup_symbol_name(entry->attr.bp_addr, fn_name) >= 0)
seq_printf(m, " %-36s", fn_name);
else
seq_printf(m, " %-36s", "<NA>");
diff --git a/samples/hw_breakpoint/data_breakpoint.c b/samples/hw_breakpoint/data_breakpoint.c
index ee7f9fb..2952550 100644
--- a/samples/hw_breakpoint/data_breakpoint.c
+++ b/samples/hw_breakpoint/data_breakpoint.c
@@ -51,13 +51,13 @@ static void sample_hbp_handler(struct perf_event *temp, void *data)
static int __init hw_break_module_init(void)
{
int ret;
- unsigned long addr;
+ DEFINE_BREAKPOINT_ATTR(attr);
- addr = kallsyms_lookup_name(ksym_name);
+ attr.bp_addr = kallsyms_lookup_name(ksym_name);
+ attr.bp_len = HW_BREAKPOINT_LEN_4;
+ attr.bp_type = HW_BREAKPOINT_W | HW_BREAKPOINT_R;
- sample_hbp = register_wide_hw_breakpoint(addr, HW_BREAKPOINT_LEN_4,
- HW_BREAKPOINT_W | HW_BREAKPOINT_R,
- sample_hbp_handler, true);
+ sample_hbp = register_wide_hw_breakpoint(&attr, sample_hbp_handler);
if (IS_ERR(sample_hbp)) {
ret = PTR_ERR(sample_hbp);
goto fail;
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