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Diffstat (limited to 'kernel/trace/trace_syscalls.c')
-rw-r--r--kernel/trace/trace_syscalls.c235
1 files changed, 142 insertions, 93 deletions
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index 527e17e..75289f3 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -14,6 +14,43 @@ static int sys_refcount_exit;
static DECLARE_BITMAP(enabled_enter_syscalls, NR_syscalls);
static DECLARE_BITMAP(enabled_exit_syscalls, NR_syscalls);
+extern unsigned long __start_syscalls_metadata[];
+extern unsigned long __stop_syscalls_metadata[];
+
+static struct syscall_metadata **syscalls_metadata;
+
+static struct syscall_metadata *find_syscall_meta(unsigned long syscall)
+{
+ struct syscall_metadata *start;
+ struct syscall_metadata *stop;
+ char str[KSYM_SYMBOL_LEN];
+
+
+ start = (struct syscall_metadata *)__start_syscalls_metadata;
+ stop = (struct syscall_metadata *)__stop_syscalls_metadata;
+ kallsyms_lookup(syscall, NULL, NULL, NULL, str);
+
+ for ( ; start < stop; start++) {
+ /*
+ * Only compare after the "sys" prefix. Archs that use
+ * syscall wrappers may have syscalls symbols aliases prefixed
+ * with "SyS" instead of "sys", leading to an unwanted
+ * mismatch.
+ */
+ if (start->name && !strcmp(start->name + 3, str + 3))
+ return start;
+ }
+ return NULL;
+}
+
+static struct syscall_metadata *syscall_nr_to_meta(int nr)
+{
+ if (!syscalls_metadata || nr >= NR_syscalls || nr < 0)
+ return NULL;
+
+ return syscalls_metadata[nr];
+}
+
enum print_line_t
print_syscall_enter(struct trace_iterator *iter, int flags)
{
@@ -30,7 +67,7 @@ print_syscall_enter(struct trace_iterator *iter, int flags)
if (!entry)
goto end;
- if (entry->enter_id != ent->type) {
+ if (entry->enter_event->id != ent->type) {
WARN_ON_ONCE(1);
goto end;
}
@@ -85,7 +122,7 @@ print_syscall_exit(struct trace_iterator *iter, int flags)
return TRACE_TYPE_HANDLED;
}
- if (entry->exit_id != ent->type) {
+ if (entry->exit_event->id != ent->type) {
WARN_ON_ONCE(1);
return TRACE_TYPE_UNHANDLED;
}
@@ -103,24 +140,19 @@ extern char *__bad_type_size(void);
#define SYSCALL_FIELD(type, name) \
sizeof(type) != sizeof(trace.name) ? \
__bad_type_size() : \
- #type, #name, offsetof(typeof(trace), name), sizeof(trace.name)
+ #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)
{
int i;
- int nr;
int ret;
- struct syscall_metadata *entry;
+ struct syscall_metadata *entry = call->data;
struct syscall_trace_enter trace;
int offset = offsetof(struct syscall_trace_enter, args);
- nr = syscall_name_to_nr(call->data);
- entry = syscall_nr_to_meta(nr);
-
- if (!entry)
- return 0;
-
- ret = trace_seq_printf(s, "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n",
+ ret = trace_seq_printf(s, "\tfield:%s %s;\toffset:%zu;\tsize:%zu;"
+ "\tsigned:%u;\n",
SYSCALL_FIELD(int, nr));
if (!ret)
return 0;
@@ -130,8 +162,10 @@ int syscall_enter_format(struct ftrace_event_call *call, struct trace_seq *s)
entry->args[i]);
if (!ret)
return 0;
- ret = trace_seq_printf(s, "\toffset:%d;\tsize:%zu;\n", offset,
- sizeof(unsigned long));
+ 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);
@@ -163,8 +197,10 @@ int syscall_exit_format(struct ftrace_event_call *call, struct trace_seq *s)
struct syscall_trace_exit trace;
ret = trace_seq_printf(s,
- "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n"
- "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n",
+ "\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)
@@ -176,19 +212,12 @@ int syscall_exit_format(struct ftrace_event_call *call, struct trace_seq *s)
int syscall_enter_define_fields(struct ftrace_event_call *call)
{
struct syscall_trace_enter trace;
- struct syscall_metadata *meta;
+ struct syscall_metadata *meta = call->data;
int ret;
- int nr;
int i;
int offset = offsetof(typeof(trace), args);
- nr = syscall_name_to_nr(call->data);
- meta = syscall_nr_to_meta(nr);
-
- if (!meta)
- return 0;
-
- ret = trace_define_common_fields(call);
+ ret = trace_define_field(call, SYSCALL_FIELD(int, nr), FILTER_OTHER);
if (ret)
return ret;
@@ -208,11 +237,11 @@ int syscall_exit_define_fields(struct ftrace_event_call *call)
struct syscall_trace_exit trace;
int ret;
- ret = trace_define_common_fields(call);
+ ret = trace_define_field(call, SYSCALL_FIELD(int, nr), FILTER_OTHER);
if (ret)
return ret;
- ret = trace_define_field(call, SYSCALL_FIELD(long, ret), 0,
+ ret = trace_define_field(call, SYSCALL_FIELD(long, ret),
FILTER_OTHER);
return ret;
@@ -239,8 +268,8 @@ void ftrace_syscall_enter(struct pt_regs *regs, long id)
size = sizeof(*entry) + sizeof(unsigned long) * sys_data->nb_args;
- event = trace_current_buffer_lock_reserve(&buffer, sys_data->enter_id,
- size, 0, 0);
+ event = trace_current_buffer_lock_reserve(&buffer,
+ sys_data->enter_event->id, size, 0, 0);
if (!event)
return;
@@ -271,8 +300,8 @@ void ftrace_syscall_exit(struct pt_regs *regs, long ret)
if (!sys_data)
return;
- event = trace_current_buffer_lock_reserve(&buffer, sys_data->exit_id,
- sizeof(*entry), 0, 0);
+ event = trace_current_buffer_lock_reserve(&buffer,
+ sys_data->exit_event->id, sizeof(*entry), 0, 0);
if (!event)
return;
@@ -285,23 +314,18 @@ void ftrace_syscall_exit(struct pt_regs *regs, long ret)
trace_current_buffer_unlock_commit(buffer, event, 0, 0);
}
-int reg_event_syscall_enter(void *ptr)
+int reg_event_syscall_enter(struct ftrace_event_call *call)
{
int ret = 0;
int num;
- char *name;
- name = (char *)ptr;
- num = syscall_name_to_nr(name);
+ num = ((struct syscall_metadata *)call->data)->syscall_nr;
if (num < 0 || num >= NR_syscalls)
return -ENOSYS;
mutex_lock(&syscall_trace_lock);
if (!sys_refcount_enter)
ret = register_trace_sys_enter(ftrace_syscall_enter);
- if (ret) {
- pr_info("event trace: Could not activate"
- "syscall entry trace point");
- } else {
+ if (!ret) {
set_bit(num, enabled_enter_syscalls);
sys_refcount_enter++;
}
@@ -309,13 +333,11 @@ int reg_event_syscall_enter(void *ptr)
return ret;
}
-void unreg_event_syscall_enter(void *ptr)
+void unreg_event_syscall_enter(struct ftrace_event_call *call)
{
int num;
- char *name;
- name = (char *)ptr;
- num = syscall_name_to_nr(name);
+ num = ((struct syscall_metadata *)call->data)->syscall_nr;
if (num < 0 || num >= NR_syscalls)
return;
mutex_lock(&syscall_trace_lock);
@@ -326,23 +348,18 @@ void unreg_event_syscall_enter(void *ptr)
mutex_unlock(&syscall_trace_lock);
}
-int reg_event_syscall_exit(void *ptr)
+int reg_event_syscall_exit(struct ftrace_event_call *call)
{
int ret = 0;
int num;
- char *name;
- name = (char *)ptr;
- num = syscall_name_to_nr(name);
+ num = ((struct syscall_metadata *)call->data)->syscall_nr;
if (num < 0 || num >= NR_syscalls)
return -ENOSYS;
mutex_lock(&syscall_trace_lock);
if (!sys_refcount_exit)
ret = register_trace_sys_exit(ftrace_syscall_exit);
- if (ret) {
- pr_info("event trace: Could not activate"
- "syscall exit trace point");
- } else {
+ if (!ret) {
set_bit(num, enabled_exit_syscalls);
sys_refcount_exit++;
}
@@ -350,13 +367,11 @@ int reg_event_syscall_exit(void *ptr)
return ret;
}
-void unreg_event_syscall_exit(void *ptr)
+void unreg_event_syscall_exit(struct ftrace_event_call *call)
{
int num;
- char *name;
- name = (char *)ptr;
- num = syscall_name_to_nr(name);
+ num = ((struct syscall_metadata *)call->data)->syscall_nr;
if (num < 0 || num >= NR_syscalls)
return;
mutex_lock(&syscall_trace_lock);
@@ -367,13 +382,44 @@ void unreg_event_syscall_exit(void *ptr)
mutex_unlock(&syscall_trace_lock);
}
-struct trace_event event_syscall_enter = {
- .trace = print_syscall_enter,
-};
+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;
+}
+
+int __init init_ftrace_syscalls(void)
+{
+ struct syscall_metadata *meta;
+ unsigned long addr;
+ int i;
+
+ syscalls_metadata = kzalloc(sizeof(*syscalls_metadata) *
+ NR_syscalls, GFP_KERNEL);
+ if (!syscalls_metadata) {
+ WARN_ON(1);
+ return -ENOMEM;
+ }
+
+ for (i = 0; i < NR_syscalls; i++) {
+ addr = arch_syscall_addr(i);
+ meta = find_syscall_meta(addr);
+ if (!meta)
+ continue;
+
+ meta->syscall_nr = i;
+ syscalls_metadata[i] = meta;
+ }
-struct trace_event event_syscall_exit = {
- .trace = print_syscall_exit,
-};
+ return 0;
+}
+core_initcall(init_ftrace_syscalls);
#ifdef CONFIG_EVENT_PROFILE
@@ -387,8 +433,10 @@ 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;
@@ -412,41 +460,42 @@ static void prof_syscall_enter(struct pt_regs *regs, long id)
/* 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();
- if (in_nmi())
- raw_data = rcu_dereference(trace_profile_buf_nmi);
- else
- raw_data = rcu_dereference(trace_profile_buf);
+ trace_buf = rcu_dereference(perf_trace_buf);
- if (!raw_data)
+ if (!trace_buf)
goto end;
- raw_data = per_cpu_ptr(raw_data, cpu);
+ 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 *) raw_data;
tracing_generic_entry_update(&rec->ent, 0, 0);
- rec->ent.type = sys_data->enter_id;
+ 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_id, 0, 1, rec, size);
+ 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);
}
-int reg_prof_syscall_enter(char *name)
+int prof_sysenter_enable(struct ftrace_event_call *call)
{
int ret = 0;
int num;
- num = syscall_name_to_nr(name);
- if (num < 0 || num >= NR_syscalls)
- return -ENOSYS;
+ num = ((struct syscall_metadata *)call->data)->syscall_nr;
mutex_lock(&syscall_trace_lock);
if (!sys_prof_refcount_enter)
@@ -462,13 +511,11 @@ int reg_prof_syscall_enter(char *name)
return ret;
}
-void unreg_prof_syscall_enter(char *name)
+void prof_sysenter_disable(struct ftrace_event_call *call)
{
int num;
- num = syscall_name_to_nr(name);
- if (num < 0 || num >= NR_syscalls)
- return;
+ num = ((struct syscall_metadata *)call->data)->syscall_nr;
mutex_lock(&syscall_trace_lock);
sys_prof_refcount_enter--;
@@ -484,7 +531,9 @@ 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;
@@ -510,17 +559,19 @@ static void prof_syscall_exit(struct pt_regs *regs, long ret)
/* 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();
- if (in_nmi())
- raw_data = rcu_dereference(trace_profile_buf_nmi);
- else
- raw_data = rcu_dereference(trace_profile_buf);
+ trace_buf = rcu_dereference(perf_trace_buf);
- if (!raw_data)
+ if (!trace_buf)
goto end;
- raw_data = per_cpu_ptr(raw_data, cpu);
+ 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;
@@ -528,24 +579,24 @@ static void prof_syscall_exit(struct pt_regs *regs, long ret)
rec = (struct syscall_trace_exit *)raw_data;
tracing_generic_entry_update(&rec->ent, 0, 0);
- rec->ent.type = sys_data->exit_id;
+ 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_id, 0, 1, rec, size);
+ 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);
}
-int reg_prof_syscall_exit(char *name)
+int prof_sysexit_enable(struct ftrace_event_call *call)
{
int ret = 0;
int num;
- num = syscall_name_to_nr(name);
- if (num < 0 || num >= NR_syscalls)
- return -ENOSYS;
+ num = ((struct syscall_metadata *)call->data)->syscall_nr;
mutex_lock(&syscall_trace_lock);
if (!sys_prof_refcount_exit)
@@ -561,13 +612,11 @@ int reg_prof_syscall_exit(char *name)
return ret;
}
-void unreg_prof_syscall_exit(char *name)
+void prof_sysexit_disable(struct ftrace_event_call *call)
{
int num;
- num = syscall_name_to_nr(name);
- if (num < 0 || num >= NR_syscalls)
- return;
+ num = ((struct syscall_metadata *)call->data)->syscall_nr;
mutex_lock(&syscall_trace_lock);
sys_prof_refcount_exit--;
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