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Diffstat (limited to 'kernel/trace/trace_syscalls.c')
-rw-r--r--kernel/trace/trace_syscalls.c189
1 files changed, 71 insertions, 118 deletions
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index 75289f3..cba47d7 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -143,70 +143,65 @@ extern char *__bad_type_size(void);
#type, #name, offsetof(typeof(trace), name), \
sizeof(trace.name), is_signed_type(type)
-int syscall_enter_format(struct ftrace_event_call *call, struct trace_seq *s)
+static
+int __set_enter_print_fmt(struct syscall_metadata *entry, char *buf, int len)
{
int i;
- int ret;
- struct syscall_metadata *entry = call->data;
- struct syscall_trace_enter trace;
- int offset = offsetof(struct syscall_trace_enter, args);
+ int pos = 0;
- ret = trace_seq_printf(s, "\tfield:%s %s;\toffset:%zu;\tsize:%zu;"
- "\tsigned:%u;\n",
- SYSCALL_FIELD(int, nr));
- if (!ret)
- return 0;
+ /* When len=0, we just calculate the needed length */
+#define LEN_OR_ZERO (len ? len - pos : 0)
+ pos += snprintf(buf + pos, LEN_OR_ZERO, "\"");
for (i = 0; i < entry->nb_args; i++) {
- ret = trace_seq_printf(s, "\tfield:%s %s;", entry->types[i],
- entry->args[i]);
- if (!ret)
- return 0;
- ret = trace_seq_printf(s, "\toffset:%d;\tsize:%zu;"
- "\tsigned:%u;\n", offset,
- sizeof(unsigned long),
- is_signed_type(unsigned long));
- if (!ret)
- return 0;
- offset += sizeof(unsigned long);
+ pos += snprintf(buf + pos, LEN_OR_ZERO, "%s: 0x%%0%zulx%s",
+ entry->args[i], sizeof(unsigned long),
+ i == entry->nb_args - 1 ? "" : ", ");
}
+ pos += snprintf(buf + pos, LEN_OR_ZERO, "\"");
- trace_seq_puts(s, "\nprint fmt: \"");
for (i = 0; i < entry->nb_args; i++) {
- ret = trace_seq_printf(s, "%s: 0x%%0%zulx%s", entry->args[i],
- sizeof(unsigned long),
- i == entry->nb_args - 1 ? "" : ", ");
- if (!ret)
- return 0;
+ pos += snprintf(buf + pos, LEN_OR_ZERO,
+ ", ((unsigned long)(REC->%s))", entry->args[i]);
}
- trace_seq_putc(s, '"');
- for (i = 0; i < entry->nb_args; i++) {
- ret = trace_seq_printf(s, ", ((unsigned long)(REC->%s))",
- entry->args[i]);
- if (!ret)
- return 0;
- }
+#undef LEN_OR_ZERO
- return trace_seq_putc(s, '\n');
+ /* return the length of print_fmt */
+ return pos;
}
-int syscall_exit_format(struct ftrace_event_call *call, struct trace_seq *s)
+static int set_syscall_print_fmt(struct ftrace_event_call *call)
{
- int ret;
- struct syscall_trace_exit trace;
+ char *print_fmt;
+ int len;
+ struct syscall_metadata *entry = call->data;
- ret = trace_seq_printf(s,
- "\tfield:%s %s;\toffset:%zu;\tsize:%zu;"
- "\tsigned:%u;\n"
- "\tfield:%s %s;\toffset:%zu;\tsize:%zu;"
- "\tsigned:%u;\n",
- SYSCALL_FIELD(int, nr),
- SYSCALL_FIELD(long, ret));
- if (!ret)
+ if (entry->enter_event != call) {
+ call->print_fmt = "\"0x%lx\", REC->ret";
return 0;
+ }
+
+ /* First: called with 0 length to calculate the needed length */
+ len = __set_enter_print_fmt(entry, NULL, 0);
+
+ print_fmt = kmalloc(len + 1, GFP_KERNEL);
+ if (!print_fmt)
+ return -ENOMEM;
+
+ /* Second: actually write the @print_fmt */
+ __set_enter_print_fmt(entry, print_fmt, len + 1);
+ call->print_fmt = print_fmt;
- return trace_seq_printf(s, "\nprint fmt: \"0x%%lx\", REC->ret\n");
+ return 0;
+}
+
+static void free_syscall_print_fmt(struct ftrace_event_call *call)
+{
+ struct syscall_metadata *entry = call->data;
+
+ if (entry->enter_event == call)
+ kfree(call->print_fmt);
}
int syscall_enter_define_fields(struct ftrace_event_call *call)
@@ -386,12 +381,22 @@ int init_syscall_trace(struct ftrace_event_call *call)
{
int id;
- id = register_ftrace_event(call->event);
- if (!id)
- return -ENODEV;
- call->id = id;
- INIT_LIST_HEAD(&call->fields);
- return 0;
+ if (set_syscall_print_fmt(call) < 0)
+ return -ENOMEM;
+
+ id = trace_event_raw_init(call);
+
+ if (id < 0) {
+ free_syscall_print_fmt(call);
+ return id;
+ }
+
+ return id;
+}
+
+unsigned long __init arch_syscall_addr(int nr)
+{
+ return (unsigned long)sys_call_table[nr];
}
int __init init_ftrace_syscalls(void)
@@ -421,7 +426,7 @@ int __init init_ftrace_syscalls(void)
}
core_initcall(init_ftrace_syscalls);
-#ifdef CONFIG_EVENT_PROFILE
+#ifdef CONFIG_PERF_EVENTS
static DECLARE_BITMAP(enabled_prof_enter_syscalls, NR_syscalls);
static DECLARE_BITMAP(enabled_prof_exit_syscalls, NR_syscalls);
@@ -433,12 +438,9 @@ static void prof_syscall_enter(struct pt_regs *regs, long id)
struct syscall_metadata *sys_data;
struct syscall_trace_enter *rec;
unsigned long flags;
- char *trace_buf;
- char *raw_data;
int syscall_nr;
int rctx;
int size;
- int cpu;
syscall_nr = syscall_get_nr(current, regs);
if (!test_bit(syscall_nr, enabled_prof_enter_syscalls))
@@ -457,37 +459,15 @@ static void prof_syscall_enter(struct pt_regs *regs, long id)
"profile buffer not large enough"))
return;
- /* Protect the per cpu buffer, begin the rcu read side */
- local_irq_save(flags);
-
- rctx = perf_swevent_get_recursion_context();
- if (rctx < 0)
- goto end_recursion;
-
- cpu = smp_processor_id();
-
- trace_buf = rcu_dereference(perf_trace_buf);
-
- if (!trace_buf)
- goto end;
-
- raw_data = per_cpu_ptr(trace_buf, cpu);
-
- /* zero the dead bytes from align to not leak stack to user */
- *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL;
+ rec = (struct syscall_trace_enter *)ftrace_perf_buf_prepare(size,
+ sys_data->enter_event->id, &rctx, &flags);
+ if (!rec)
+ return;
- rec = (struct syscall_trace_enter *) raw_data;
- tracing_generic_entry_update(&rec->ent, 0, 0);
- rec->ent.type = sys_data->enter_event->id;
rec->nr = syscall_nr;
syscall_get_arguments(current, regs, 0, sys_data->nb_args,
(unsigned long *)&rec->args);
- perf_tp_event(sys_data->enter_event->id, 0, 1, rec, size);
-
-end:
- perf_swevent_put_recursion_context(rctx);
-end_recursion:
- local_irq_restore(flags);
+ ftrace_perf_buf_submit(rec, size, rctx, 0, 1, flags);
}
int prof_sysenter_enable(struct ftrace_event_call *call)
@@ -531,11 +511,8 @@ static void prof_syscall_exit(struct pt_regs *regs, long ret)
struct syscall_trace_exit *rec;
unsigned long flags;
int syscall_nr;
- char *trace_buf;
- char *raw_data;
int rctx;
int size;
- int cpu;
syscall_nr = syscall_get_nr(current, regs);
if (!test_bit(syscall_nr, enabled_prof_exit_syscalls))
@@ -557,38 +534,15 @@ static void prof_syscall_exit(struct pt_regs *regs, long ret)
"exit event has grown above profile buffer size"))
return;
- /* Protect the per cpu buffer, begin the rcu read side */
- local_irq_save(flags);
-
- rctx = perf_swevent_get_recursion_context();
- if (rctx < 0)
- goto end_recursion;
-
- cpu = smp_processor_id();
-
- trace_buf = rcu_dereference(perf_trace_buf);
-
- if (!trace_buf)
- goto end;
-
- raw_data = per_cpu_ptr(trace_buf, cpu);
-
- /* zero the dead bytes from align to not leak stack to user */
- *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL;
-
- rec = (struct syscall_trace_exit *)raw_data;
+ rec = (struct syscall_trace_exit *)ftrace_perf_buf_prepare(size,
+ sys_data->exit_event->id, &rctx, &flags);
+ if (!rec)
+ return;
- tracing_generic_entry_update(&rec->ent, 0, 0);
- rec->ent.type = sys_data->exit_event->id;
rec->nr = syscall_nr;
rec->ret = syscall_get_return_value(current, regs);
- perf_tp_event(sys_data->exit_event->id, 0, 1, rec, size);
-
-end:
- perf_swevent_put_recursion_context(rctx);
-end_recursion:
- local_irq_restore(flags);
+ ftrace_perf_buf_submit(rec, size, rctx, 0, 1, flags);
}
int prof_sysexit_enable(struct ftrace_event_call *call)
@@ -603,7 +557,7 @@ int prof_sysexit_enable(struct ftrace_event_call *call)
ret = register_trace_sys_exit(prof_syscall_exit);
if (ret) {
pr_info("event trace: Could not activate"
- "syscall entry trace point");
+ "syscall exit trace point");
} else {
set_bit(num, enabled_prof_exit_syscalls);
sys_prof_refcount_exit++;
@@ -626,6 +580,5 @@ void prof_sysexit_disable(struct ftrace_event_call *call)
mutex_unlock(&syscall_trace_lock);
}
-#endif
-
+#endif /* CONFIG_PERF_EVENTS */
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