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Diffstat (limited to 'kernel/trace/trace_ksym.c')
-rw-r--r--kernel/trace/trace_ksym.c126
1 files changed, 60 insertions, 66 deletions
diff --git a/kernel/trace/trace_ksym.c b/kernel/trace/trace_ksym.c
index 6d5609c6737..fea83eeeef0 100644
--- a/kernel/trace/trace_ksym.c
+++ b/kernel/trace/trace_ksym.c
@@ -29,7 +29,11 @@
#include "trace_stat.h"
#include "trace.h"
-/* For now, let us restrict the no. of symbols traced simultaneously to number
+#include <linux/hw_breakpoint.h>
+#include <asm/hw_breakpoint.h>
+
+/*
+ * For now, let us restrict the no. of symbols traced simultaneously to number
* of available hardware breakpoint registers.
*/
#define KSYM_TRACER_MAX HBP_NUM
@@ -37,8 +41,10 @@
#define KSYM_TRACER_OP_LEN 3 /* rw- */
struct trace_ksym {
- struct hw_breakpoint *ksym_hbp;
+ struct perf_event **ksym_hbp;
unsigned long ksym_addr;
+ int type;
+ int len;
#ifdef CONFIG_PROFILE_KSYM_TRACER
unsigned long counter;
#endif
@@ -75,10 +81,11 @@ void ksym_collect_stats(unsigned long hbp_hit_addr)
}
#endif /* CONFIG_PROFILE_KSYM_TRACER */
-void ksym_hbp_handler(struct hw_breakpoint *hbp, struct pt_regs *regs)
+void ksym_hbp_handler(struct perf_event *hbp, void *data)
{
struct ring_buffer_event *event;
struct ksym_trace_entry *entry;
+ struct pt_regs *regs = data;
struct ring_buffer *buffer;
int pc;
@@ -96,12 +103,12 @@ void ksym_hbp_handler(struct hw_breakpoint *hbp, struct pt_regs *regs)
entry = ring_buffer_event_data(event);
entry->ip = instruction_pointer(regs);
- entry->type = hbp->info.type;
- strlcpy(entry->ksym_name, hbp->info.name, KSYM_SYMBOL_LEN);
+ entry->type = hw_breakpoint_type(hbp);
+ entry->addr = hw_breakpoint_addr(hbp);
strlcpy(entry->cmd, current->comm, TASK_COMM_LEN);
#ifdef CONFIG_PROFILE_KSYM_TRACER
- ksym_collect_stats(hbp->info.address);
+ ksym_collect_stats(hw_breakpoint_addr(hbp));
#endif /* CONFIG_PROFILE_KSYM_TRACER */
trace_buffer_unlock_commit(buffer, event, 0, pc);
@@ -120,31 +127,21 @@ static int ksym_trace_get_access_type(char *str)
int access = 0;
if (str[0] == 'r')
- access += 4;
- else if (str[0] != '-')
- return -EINVAL;
+ access |= HW_BREAKPOINT_R;
if (str[1] == 'w')
- access += 2;
- else if (str[1] != '-')
- return -EINVAL;
+ access |= HW_BREAKPOINT_W;
- if (str[2] != '-')
- return -EINVAL;
+ if (str[2] == 'x')
+ access |= HW_BREAKPOINT_X;
switch (access) {
- case 6:
- access = HW_BREAKPOINT_RW;
- break;
- case 4:
- access = -EINVAL;
- break;
- case 2:
- access = HW_BREAKPOINT_WRITE;
- break;
+ case HW_BREAKPOINT_W:
+ case HW_BREAKPOINT_W | HW_BREAKPOINT_R:
+ return access;
+ default:
+ return -EINVAL;
}
-
- return access;
}
/*
@@ -194,36 +191,33 @@ int process_new_ksym_entry(char *ksymname, int op, unsigned long addr)
if (!entry)
return -ENOMEM;
- entry->ksym_hbp = kzalloc(sizeof(struct hw_breakpoint), GFP_KERNEL);
- if (!entry->ksym_hbp)
- goto err;
-
- entry->ksym_hbp->info.name = kstrdup(ksymname, GFP_KERNEL);
- if (!entry->ksym_hbp->info.name)
- goto err;
-
- entry->ksym_hbp->info.type = op;
- entry->ksym_addr = entry->ksym_hbp->info.address = addr;
-#ifdef CONFIG_X86
- entry->ksym_hbp->info.len = HW_BREAKPOINT_LEN_4;
-#endif
- entry->ksym_hbp->triggered = (void *)ksym_hbp_handler;
+ entry->type = op;
+ entry->ksym_addr = addr;
+ entry->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);
+ if (IS_ERR(entry->ksym_hbp)) {
+ entry->ksym_hbp = NULL;
+ ret = PTR_ERR(entry->ksym_hbp);
+ }
- ret = register_kernel_hw_breakpoint(entry->ksym_hbp);
- if (ret < 0) {
+ if (!entry->ksym_hbp) {
printk(KERN_INFO "ksym_tracer request failed. Try again"
" later!!\n");
- ret = -EAGAIN;
goto err;
}
+
hlist_add_head_rcu(&(entry->ksym_hlist), &ksym_filter_head);
ksym_filter_entry_count++;
+
return 0;
+
err:
- if (entry->ksym_hbp)
- kfree(entry->ksym_hbp->info.name);
- kfree(entry->ksym_hbp);
kfree(entry);
+
return ret;
}
@@ -244,10 +238,10 @@ 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, "%s:", entry->ksym_hbp->info.name);
- if (entry->ksym_hbp->info.type == HW_BREAKPOINT_WRITE)
+ ret = trace_seq_printf(s, "%pS:", (void *)entry->ksym_addr);
+ if (entry->type == HW_BREAKPOINT_W)
ret = trace_seq_puts(s, "-w-\n");
- else if (entry->ksym_hbp->info.type == HW_BREAKPOINT_RW)
+ else if (entry->type == (HW_BREAKPOINT_W | HW_BREAKPOINT_R))
ret = trace_seq_puts(s, "rw-\n");
WARN_ON_ONCE(!ret);
}
@@ -269,12 +263,10 @@ static void __ksym_trace_reset(void)
mutex_lock(&ksym_tracer_mutex);
hlist_for_each_entry_safe(entry, node, node1, &ksym_filter_head,
ksym_hlist) {
- unregister_kernel_hw_breakpoint(entry->ksym_hbp);
+ unregister_wide_hw_breakpoint(entry->ksym_hbp);
ksym_filter_entry_count--;
hlist_del_rcu(&(entry->ksym_hlist));
synchronize_rcu();
- kfree(entry->ksym_hbp->info.name);
- kfree(entry->ksym_hbp);
kfree(entry);
}
mutex_unlock(&ksym_tracer_mutex);
@@ -327,7 +319,7 @@ static ssize_t ksym_trace_filter_write(struct file *file,
hlist_for_each_entry(entry, node, &ksym_filter_head, ksym_hlist) {
if (entry->ksym_addr == ksym_addr) {
/* Check for malformed request: (6) */
- if (entry->ksym_hbp->info.type != op)
+ if (entry->type != op)
changed = 1;
else
goto out;
@@ -335,18 +327,21 @@ static ssize_t ksym_trace_filter_write(struct file *file,
}
}
if (changed) {
- unregister_kernel_hw_breakpoint(entry->ksym_hbp);
- entry->ksym_hbp->info.type = op;
+ unregister_wide_hw_breakpoint(entry->ksym_hbp);
+ entry->type = op;
if (op > 0) {
- ret = register_kernel_hw_breakpoint(entry->ksym_hbp);
- if (ret == 0)
+ entry->ksym_hbp =
+ register_wide_hw_breakpoint(entry->ksym_addr,
+ entry->len, entry->type,
+ ksym_hbp_handler, true);
+ if (IS_ERR(entry->ksym_hbp))
+ entry->ksym_hbp = NULL;
+ if (!entry->ksym_hbp)
goto out;
}
ksym_filter_entry_count--;
hlist_del_rcu(&(entry->ksym_hlist));
synchronize_rcu();
- kfree(entry->ksym_hbp->info.name);
- kfree(entry->ksym_hbp);
kfree(entry);
ret = 0;
goto out;
@@ -413,16 +408,16 @@ static enum print_line_t ksym_trace_output(struct trace_iterator *iter)
trace_assign_type(field, entry);
- ret = trace_seq_printf(s, "%11s-%-5d [%03d] %-30s ", field->cmd,
- entry->pid, iter->cpu, field->ksym_name);
+ ret = trace_seq_printf(s, "%11s-%-5d [%03d] %pS", field->cmd,
+ entry->pid, iter->cpu, (char *)field->addr);
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
switch (field->type) {
- case HW_BREAKPOINT_WRITE:
+ case HW_BREAKPOINT_W:
ret = trace_seq_printf(s, " W ");
break;
- case HW_BREAKPOINT_RW:
+ case HW_BREAKPOINT_R | HW_BREAKPOINT_W:
ret = trace_seq_printf(s, " RW ");
break;
default:
@@ -490,14 +485,13 @@ static int ksym_tracer_stat_show(struct seq_file *m, void *v)
entry = hlist_entry(stat, struct trace_ksym, ksym_hlist);
- if (entry->ksym_hbp)
- access_type = entry->ksym_hbp->info.type;
+ access_type = entry->type;
switch (access_type) {
- case HW_BREAKPOINT_WRITE:
+ case HW_BREAKPOINT_W:
seq_puts(m, " W ");
break;
- case HW_BREAKPOINT_RW:
+ case HW_BREAKPOINT_R | HW_BREAKPOINT_W:
seq_puts(m, " RW ");
break;
default: