diff options
Diffstat (limited to 'kernel/trace/trace_syscalls.c')
-rw-r--r-- | kernel/trace/trace_syscalls.c | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c index e58a9c11ba8..f4eaec3d559 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -1,6 +1,7 @@ #include <trace/syscall.h> #include <linux/kernel.h> #include <linux/ftrace.h> +#include <linux/perf_counter.h> #include <asm/syscall.h> #include "trace_output.h" @@ -252,3 +253,123 @@ struct trace_event event_syscall_enter = { struct trace_event event_syscall_exit = { .trace = print_syscall_exit, }; + +#ifdef CONFIG_EVENT_PROFILE +static DECLARE_BITMAP(enabled_prof_enter_syscalls, FTRACE_SYSCALL_MAX); +static DECLARE_BITMAP(enabled_prof_exit_syscalls, FTRACE_SYSCALL_MAX); +static int sys_prof_refcount_enter; +static int sys_prof_refcount_exit; + +static void prof_syscall_enter(struct pt_regs *regs, long id) +{ + struct syscall_metadata *sys_data; + int syscall_nr; + + syscall_nr = syscall_get_nr(current, regs); + if (!test_bit(syscall_nr, enabled_prof_enter_syscalls)) + return; + + sys_data = syscall_nr_to_meta(syscall_nr); + if (!sys_data) + return; + + perf_tpcounter_event(sys_data->enter_id, 0, 1, NULL, 0); +} + +int reg_prof_syscall_enter(char *name) +{ + int ret = 0; + int num; + + num = syscall_name_to_nr(name); + if (num < 0 || num >= FTRACE_SYSCALL_MAX) + return -ENOSYS; + + mutex_lock(&syscall_trace_lock); + if (!sys_prof_refcount_enter) + ret = register_trace_syscall_enter(prof_syscall_enter); + if (ret) { + pr_info("event trace: Could not activate" + "syscall entry trace point"); + } else { + set_bit(num, enabled_prof_enter_syscalls); + sys_prof_refcount_enter++; + } + mutex_unlock(&syscall_trace_lock); + return ret; +} + +void unreg_prof_syscall_enter(char *name) +{ + int num; + + num = syscall_name_to_nr(name); + if (num < 0 || num >= FTRACE_SYSCALL_MAX) + return; + + mutex_lock(&syscall_trace_lock); + sys_prof_refcount_enter--; + clear_bit(num, enabled_prof_enter_syscalls); + if (!sys_prof_refcount_enter) + unregister_trace_syscall_enter(prof_syscall_enter); + mutex_unlock(&syscall_trace_lock); +} + +static void prof_syscall_exit(struct pt_regs *regs, long ret) +{ + struct syscall_metadata *sys_data; + int syscall_nr; + + syscall_nr = syscall_get_nr(current, regs); + if (!test_bit(syscall_nr, enabled_prof_exit_syscalls)) + return; + + sys_data = syscall_nr_to_meta(syscall_nr); + if (!sys_data) + return; + + perf_tpcounter_event(sys_data->exit_id, 0, 1, NULL, 0); +} + +int reg_prof_syscall_exit(char *name) +{ + int ret = 0; + int num; + + num = syscall_name_to_nr(name); + if (num < 0 || num >= FTRACE_SYSCALL_MAX) + return -ENOSYS; + + mutex_lock(&syscall_trace_lock); + if (!sys_prof_refcount_exit) + ret = register_trace_syscall_exit(prof_syscall_exit); + if (ret) { + pr_info("event trace: Could not activate" + "syscall entry trace point"); + } else { + set_bit(num, enabled_prof_exit_syscalls); + sys_prof_refcount_exit++; + } + mutex_unlock(&syscall_trace_lock); + return ret; +} + +void unreg_prof_syscall_exit(char *name) +{ + int num; + + num = syscall_name_to_nr(name); + if (num < 0 || num >= FTRACE_SYSCALL_MAX) + return; + + mutex_lock(&syscall_trace_lock); + sys_prof_refcount_exit--; + clear_bit(num, enabled_prof_exit_syscalls); + if (!sys_prof_refcount_exit) + unregister_trace_syscall_exit(prof_syscall_exit); + mutex_unlock(&syscall_trace_lock); +} + +#endif + + |