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![Peter Zijlstra (Intel)](/assets/img/avatar_default.png)
Both Linus (most recent) and Steve (a while ago) reported that perf related callbacks have massive stack bloat. The problem is that software events need a pt_regs in order to properly report the event location and unwind stack. And because we could not assume one was present we allocated one on stack and filled it with minimal bits required for operation. Now, pt_regs is quite large, so this is undesirable. Furthermore it turns out that most sites actually have a pt_regs pointer available, making this even more onerous, as the stack space is pointless waste. This patch addresses the problem by observing that software events have well defined nesting semantics, therefore we can use static per-cpu storage instead of on-stack. Linus made the further observation that all but the scheduler callers of perf_sw_event() have a pt_regs available, so we change the regular perf_sw_event() to require a valid pt_regs (where it used to be optional) and add perf_sw_event_sched() for the scheduler. We have a scheduler specific call instead of a more generic _noregs() like construct because we can assume non-recursion from the scheduler and thereby simplify the code further (_noregs would have to put the recursion context call inline in order to assertain which __perf_regs element to use). One last note on the implementation of perf_trace_buf_prepare(); we allow .regs = NULL for those cases where we already have a pt_regs pointer available and do not need another. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Reported-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Javi Merino <javi.merino@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Petr Mladek <pmladek@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Tom Zanussi <tom.zanussi@linux.intel.com> Cc: Vaibhav Nagarnaik <vnagarnaik@google.com> Link: http://lkml.kernel.org/r/20141216115041.GW3337@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
750 lines
18 KiB
C
750 lines
18 KiB
C
#include <trace/syscall.h>
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#include <trace/events/syscalls.h>
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#include <linux/syscalls.h>
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#include <linux/slab.h>
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#include <linux/kernel.h>
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#include <linux/module.h> /* for MODULE_NAME_LEN via KSYM_SYMBOL_LEN */
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#include <linux/ftrace.h>
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#include <linux/perf_event.h>
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#include <asm/syscall.h>
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#include "trace_output.h"
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#include "trace.h"
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static DEFINE_MUTEX(syscall_trace_lock);
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static int syscall_enter_register(struct ftrace_event_call *event,
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enum trace_reg type, void *data);
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static int syscall_exit_register(struct ftrace_event_call *event,
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enum trace_reg type, void *data);
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static struct list_head *
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syscall_get_enter_fields(struct ftrace_event_call *call)
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{
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struct syscall_metadata *entry = call->data;
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return &entry->enter_fields;
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}
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extern struct syscall_metadata *__start_syscalls_metadata[];
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extern struct syscall_metadata *__stop_syscalls_metadata[];
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static struct syscall_metadata **syscalls_metadata;
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#ifndef ARCH_HAS_SYSCALL_MATCH_SYM_NAME
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static inline bool arch_syscall_match_sym_name(const char *sym, const char *name)
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{
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/*
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* Only compare after the "sys" prefix. Archs that use
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* syscall wrappers may have syscalls symbols aliases prefixed
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* with ".SyS" or ".sys" instead of "sys", leading to an unwanted
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* mismatch.
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*/
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return !strcmp(sym + 3, name + 3);
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}
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#endif
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#ifdef ARCH_TRACE_IGNORE_COMPAT_SYSCALLS
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/*
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* Some architectures that allow for 32bit applications
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* to run on a 64bit kernel, do not map the syscalls for
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* the 32bit tasks the same as they do for 64bit tasks.
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*
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* *cough*x86*cough*
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*
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* In such a case, instead of reporting the wrong syscalls,
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* simply ignore them.
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*
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* For an arch to ignore the compat syscalls it needs to
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* define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS as well as
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* define the function arch_trace_is_compat_syscall() to let
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* the tracing system know that it should ignore it.
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*/
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static int
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trace_get_syscall_nr(struct task_struct *task, struct pt_regs *regs)
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{
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if (unlikely(arch_trace_is_compat_syscall(regs)))
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return -1;
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return syscall_get_nr(task, regs);
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}
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#else
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static inline int
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trace_get_syscall_nr(struct task_struct *task, struct pt_regs *regs)
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{
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return syscall_get_nr(task, regs);
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}
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#endif /* ARCH_TRACE_IGNORE_COMPAT_SYSCALLS */
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static __init struct syscall_metadata *
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find_syscall_meta(unsigned long syscall)
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{
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struct syscall_metadata **start;
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struct syscall_metadata **stop;
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char str[KSYM_SYMBOL_LEN];
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start = __start_syscalls_metadata;
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stop = __stop_syscalls_metadata;
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kallsyms_lookup(syscall, NULL, NULL, NULL, str);
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if (arch_syscall_match_sym_name(str, "sys_ni_syscall"))
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return NULL;
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for ( ; start < stop; start++) {
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if ((*start)->name && arch_syscall_match_sym_name(str, (*start)->name))
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return *start;
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}
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return NULL;
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}
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static struct syscall_metadata *syscall_nr_to_meta(int nr)
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{
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if (!syscalls_metadata || nr >= NR_syscalls || nr < 0)
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return NULL;
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return syscalls_metadata[nr];
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}
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static enum print_line_t
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print_syscall_enter(struct trace_iterator *iter, int flags,
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struct trace_event *event)
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{
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struct trace_seq *s = &iter->seq;
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struct trace_entry *ent = iter->ent;
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struct syscall_trace_enter *trace;
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struct syscall_metadata *entry;
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int i, syscall;
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trace = (typeof(trace))ent;
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syscall = trace->nr;
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entry = syscall_nr_to_meta(syscall);
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if (!entry)
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goto end;
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if (entry->enter_event->event.type != ent->type) {
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WARN_ON_ONCE(1);
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goto end;
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}
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trace_seq_printf(s, "%s(", entry->name);
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for (i = 0; i < entry->nb_args; i++) {
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if (trace_seq_has_overflowed(s))
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goto end;
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/* parameter types */
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if (trace_flags & TRACE_ITER_VERBOSE)
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trace_seq_printf(s, "%s ", entry->types[i]);
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/* parameter values */
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trace_seq_printf(s, "%s: %lx%s", entry->args[i],
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trace->args[i],
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i == entry->nb_args - 1 ? "" : ", ");
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}
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trace_seq_putc(s, ')');
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end:
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trace_seq_putc(s, '\n');
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return trace_handle_return(s);
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}
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static enum print_line_t
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print_syscall_exit(struct trace_iterator *iter, int flags,
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struct trace_event *event)
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{
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struct trace_seq *s = &iter->seq;
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struct trace_entry *ent = iter->ent;
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struct syscall_trace_exit *trace;
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int syscall;
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struct syscall_metadata *entry;
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trace = (typeof(trace))ent;
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syscall = trace->nr;
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entry = syscall_nr_to_meta(syscall);
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if (!entry) {
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trace_seq_putc(s, '\n');
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goto out;
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}
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if (entry->exit_event->event.type != ent->type) {
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WARN_ON_ONCE(1);
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return TRACE_TYPE_UNHANDLED;
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}
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trace_seq_printf(s, "%s -> 0x%lx\n", entry->name,
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trace->ret);
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out:
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return trace_handle_return(s);
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}
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extern char *__bad_type_size(void);
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#define SYSCALL_FIELD(type, name) \
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sizeof(type) != sizeof(trace.name) ? \
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__bad_type_size() : \
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#type, #name, offsetof(typeof(trace), name), \
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sizeof(trace.name), is_signed_type(type)
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static int __init
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__set_enter_print_fmt(struct syscall_metadata *entry, char *buf, int len)
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{
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int i;
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int pos = 0;
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/* When len=0, we just calculate the needed length */
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#define LEN_OR_ZERO (len ? len - pos : 0)
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pos += snprintf(buf + pos, LEN_OR_ZERO, "\"");
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for (i = 0; i < entry->nb_args; i++) {
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pos += snprintf(buf + pos, LEN_OR_ZERO, "%s: 0x%%0%zulx%s",
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entry->args[i], sizeof(unsigned long),
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i == entry->nb_args - 1 ? "" : ", ");
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}
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pos += snprintf(buf + pos, LEN_OR_ZERO, "\"");
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for (i = 0; i < entry->nb_args; i++) {
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pos += snprintf(buf + pos, LEN_OR_ZERO,
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", ((unsigned long)(REC->%s))", entry->args[i]);
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}
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#undef LEN_OR_ZERO
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/* return the length of print_fmt */
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return pos;
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}
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static int __init set_syscall_print_fmt(struct ftrace_event_call *call)
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{
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char *print_fmt;
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int len;
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struct syscall_metadata *entry = call->data;
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if (entry->enter_event != call) {
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call->print_fmt = "\"0x%lx\", REC->ret";
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return 0;
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}
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/* First: called with 0 length to calculate the needed length */
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len = __set_enter_print_fmt(entry, NULL, 0);
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print_fmt = kmalloc(len + 1, GFP_KERNEL);
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if (!print_fmt)
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return -ENOMEM;
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/* Second: actually write the @print_fmt */
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__set_enter_print_fmt(entry, print_fmt, len + 1);
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call->print_fmt = print_fmt;
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return 0;
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}
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static void __init free_syscall_print_fmt(struct ftrace_event_call *call)
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{
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struct syscall_metadata *entry = call->data;
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if (entry->enter_event == call)
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kfree(call->print_fmt);
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}
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static int __init syscall_enter_define_fields(struct ftrace_event_call *call)
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{
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struct syscall_trace_enter trace;
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struct syscall_metadata *meta = call->data;
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int ret;
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int i;
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int offset = offsetof(typeof(trace), args);
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ret = trace_define_field(call, SYSCALL_FIELD(int, nr), FILTER_OTHER);
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if (ret)
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return ret;
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for (i = 0; i < meta->nb_args; i++) {
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ret = trace_define_field(call, meta->types[i],
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meta->args[i], offset,
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sizeof(unsigned long), 0,
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FILTER_OTHER);
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offset += sizeof(unsigned long);
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}
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return ret;
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}
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static int __init syscall_exit_define_fields(struct ftrace_event_call *call)
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{
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struct syscall_trace_exit trace;
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int ret;
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ret = trace_define_field(call, SYSCALL_FIELD(int, nr), FILTER_OTHER);
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if (ret)
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return ret;
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ret = trace_define_field(call, SYSCALL_FIELD(long, ret),
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FILTER_OTHER);
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return ret;
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}
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static void ftrace_syscall_enter(void *data, struct pt_regs *regs, long id)
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{
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struct trace_array *tr = data;
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struct ftrace_event_file *ftrace_file;
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struct syscall_trace_enter *entry;
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struct syscall_metadata *sys_data;
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struct ring_buffer_event *event;
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struct ring_buffer *buffer;
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unsigned long irq_flags;
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int pc;
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int syscall_nr;
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int size;
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syscall_nr = trace_get_syscall_nr(current, regs);
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if (syscall_nr < 0 || syscall_nr >= NR_syscalls)
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return;
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/* Here we're inside tp handler's rcu_read_lock_sched (__DO_TRACE) */
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ftrace_file = rcu_dereference_sched(tr->enter_syscall_files[syscall_nr]);
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if (!ftrace_file)
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return;
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if (ftrace_trigger_soft_disabled(ftrace_file))
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return;
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sys_data = syscall_nr_to_meta(syscall_nr);
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if (!sys_data)
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return;
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size = sizeof(*entry) + sizeof(unsigned long) * sys_data->nb_args;
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local_save_flags(irq_flags);
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pc = preempt_count();
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buffer = tr->trace_buffer.buffer;
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event = trace_buffer_lock_reserve(buffer,
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sys_data->enter_event->event.type, size, irq_flags, pc);
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if (!event)
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return;
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entry = ring_buffer_event_data(event);
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entry->nr = syscall_nr;
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syscall_get_arguments(current, regs, 0, sys_data->nb_args, entry->args);
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event_trigger_unlock_commit(ftrace_file, buffer, event, entry,
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irq_flags, pc);
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}
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static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret)
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{
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struct trace_array *tr = data;
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struct ftrace_event_file *ftrace_file;
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struct syscall_trace_exit *entry;
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struct syscall_metadata *sys_data;
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struct ring_buffer_event *event;
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struct ring_buffer *buffer;
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unsigned long irq_flags;
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int pc;
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int syscall_nr;
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syscall_nr = trace_get_syscall_nr(current, regs);
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if (syscall_nr < 0 || syscall_nr >= NR_syscalls)
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return;
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/* Here we're inside tp handler's rcu_read_lock_sched (__DO_TRACE()) */
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ftrace_file = rcu_dereference_sched(tr->exit_syscall_files[syscall_nr]);
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if (!ftrace_file)
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return;
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if (ftrace_trigger_soft_disabled(ftrace_file))
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return;
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sys_data = syscall_nr_to_meta(syscall_nr);
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if (!sys_data)
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return;
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local_save_flags(irq_flags);
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pc = preempt_count();
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buffer = tr->trace_buffer.buffer;
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event = trace_buffer_lock_reserve(buffer,
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sys_data->exit_event->event.type, sizeof(*entry),
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irq_flags, pc);
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if (!event)
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return;
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entry = ring_buffer_event_data(event);
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entry->nr = syscall_nr;
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entry->ret = syscall_get_return_value(current, regs);
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event_trigger_unlock_commit(ftrace_file, buffer, event, entry,
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irq_flags, pc);
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}
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static int reg_event_syscall_enter(struct ftrace_event_file *file,
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struct ftrace_event_call *call)
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{
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struct trace_array *tr = file->tr;
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int ret = 0;
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int num;
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num = ((struct syscall_metadata *)call->data)->syscall_nr;
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if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls))
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return -ENOSYS;
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mutex_lock(&syscall_trace_lock);
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if (!tr->sys_refcount_enter)
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ret = register_trace_sys_enter(ftrace_syscall_enter, tr);
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if (!ret) {
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rcu_assign_pointer(tr->enter_syscall_files[num], file);
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tr->sys_refcount_enter++;
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}
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mutex_unlock(&syscall_trace_lock);
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return ret;
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}
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static void unreg_event_syscall_enter(struct ftrace_event_file *file,
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struct ftrace_event_call *call)
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{
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struct trace_array *tr = file->tr;
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int num;
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num = ((struct syscall_metadata *)call->data)->syscall_nr;
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if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls))
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return;
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mutex_lock(&syscall_trace_lock);
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tr->sys_refcount_enter--;
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RCU_INIT_POINTER(tr->enter_syscall_files[num], NULL);
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if (!tr->sys_refcount_enter)
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unregister_trace_sys_enter(ftrace_syscall_enter, tr);
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mutex_unlock(&syscall_trace_lock);
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}
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static int reg_event_syscall_exit(struct ftrace_event_file *file,
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struct ftrace_event_call *call)
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{
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struct trace_array *tr = file->tr;
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int ret = 0;
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int num;
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num = ((struct syscall_metadata *)call->data)->syscall_nr;
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if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls))
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return -ENOSYS;
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mutex_lock(&syscall_trace_lock);
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if (!tr->sys_refcount_exit)
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ret = register_trace_sys_exit(ftrace_syscall_exit, tr);
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if (!ret) {
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rcu_assign_pointer(tr->exit_syscall_files[num], file);
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tr->sys_refcount_exit++;
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}
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mutex_unlock(&syscall_trace_lock);
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return ret;
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}
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static void unreg_event_syscall_exit(struct ftrace_event_file *file,
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struct ftrace_event_call *call)
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{
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struct trace_array *tr = file->tr;
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int num;
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num = ((struct syscall_metadata *)call->data)->syscall_nr;
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if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls))
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return;
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mutex_lock(&syscall_trace_lock);
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tr->sys_refcount_exit--;
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RCU_INIT_POINTER(tr->exit_syscall_files[num], NULL);
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if (!tr->sys_refcount_exit)
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unregister_trace_sys_exit(ftrace_syscall_exit, tr);
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mutex_unlock(&syscall_trace_lock);
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}
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static int __init init_syscall_trace(struct ftrace_event_call *call)
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{
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int id;
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int num;
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num = ((struct syscall_metadata *)call->data)->syscall_nr;
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if (num < 0 || num >= NR_syscalls) {
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pr_debug("syscall %s metadata not mapped, disabling ftrace event\n",
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((struct syscall_metadata *)call->data)->name);
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return -ENOSYS;
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}
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if (set_syscall_print_fmt(call) < 0)
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return -ENOMEM;
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id = trace_event_raw_init(call);
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if (id < 0) {
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free_syscall_print_fmt(call);
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return id;
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}
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return id;
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}
|
|
|
|
struct trace_event_functions enter_syscall_print_funcs = {
|
|
.trace = print_syscall_enter,
|
|
};
|
|
|
|
struct trace_event_functions exit_syscall_print_funcs = {
|
|
.trace = print_syscall_exit,
|
|
};
|
|
|
|
struct ftrace_event_class __refdata event_class_syscall_enter = {
|
|
.system = "syscalls",
|
|
.reg = syscall_enter_register,
|
|
.define_fields = syscall_enter_define_fields,
|
|
.get_fields = syscall_get_enter_fields,
|
|
.raw_init = init_syscall_trace,
|
|
};
|
|
|
|
struct ftrace_event_class __refdata event_class_syscall_exit = {
|
|
.system = "syscalls",
|
|
.reg = syscall_exit_register,
|
|
.define_fields = syscall_exit_define_fields,
|
|
.fields = LIST_HEAD_INIT(event_class_syscall_exit.fields),
|
|
.raw_init = init_syscall_trace,
|
|
};
|
|
|
|
unsigned long __init __weak arch_syscall_addr(int nr)
|
|
{
|
|
return (unsigned long)sys_call_table[nr];
|
|
}
|
|
|
|
void __init init_ftrace_syscalls(void)
|
|
{
|
|
struct syscall_metadata *meta;
|
|
unsigned long addr;
|
|
int i;
|
|
|
|
syscalls_metadata = kcalloc(NR_syscalls, sizeof(*syscalls_metadata),
|
|
GFP_KERNEL);
|
|
if (!syscalls_metadata) {
|
|
WARN_ON(1);
|
|
return;
|
|
}
|
|
|
|
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;
|
|
}
|
|
}
|
|
|
|
#ifdef CONFIG_PERF_EVENTS
|
|
|
|
static DECLARE_BITMAP(enabled_perf_enter_syscalls, NR_syscalls);
|
|
static DECLARE_BITMAP(enabled_perf_exit_syscalls, NR_syscalls);
|
|
static int sys_perf_refcount_enter;
|
|
static int sys_perf_refcount_exit;
|
|
|
|
static void perf_syscall_enter(void *ignore, struct pt_regs *regs, long id)
|
|
{
|
|
struct syscall_metadata *sys_data;
|
|
struct syscall_trace_enter *rec;
|
|
struct hlist_head *head;
|
|
int syscall_nr;
|
|
int rctx;
|
|
int size;
|
|
|
|
syscall_nr = trace_get_syscall_nr(current, regs);
|
|
if (syscall_nr < 0 || syscall_nr >= NR_syscalls)
|
|
return;
|
|
if (!test_bit(syscall_nr, enabled_perf_enter_syscalls))
|
|
return;
|
|
|
|
sys_data = syscall_nr_to_meta(syscall_nr);
|
|
if (!sys_data)
|
|
return;
|
|
|
|
head = this_cpu_ptr(sys_data->enter_event->perf_events);
|
|
if (hlist_empty(head))
|
|
return;
|
|
|
|
/* get the size after alignment with the u32 buffer size field */
|
|
size = sizeof(unsigned long) * sys_data->nb_args + sizeof(*rec);
|
|
size = ALIGN(size + sizeof(u32), sizeof(u64));
|
|
size -= sizeof(u32);
|
|
|
|
rec = (struct syscall_trace_enter *)perf_trace_buf_prepare(size,
|
|
sys_data->enter_event->event.type, NULL, &rctx);
|
|
if (!rec)
|
|
return;
|
|
|
|
rec->nr = syscall_nr;
|
|
syscall_get_arguments(current, regs, 0, sys_data->nb_args,
|
|
(unsigned long *)&rec->args);
|
|
perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head, NULL);
|
|
}
|
|
|
|
static int perf_sysenter_enable(struct ftrace_event_call *call)
|
|
{
|
|
int ret = 0;
|
|
int num;
|
|
|
|
num = ((struct syscall_metadata *)call->data)->syscall_nr;
|
|
|
|
mutex_lock(&syscall_trace_lock);
|
|
if (!sys_perf_refcount_enter)
|
|
ret = register_trace_sys_enter(perf_syscall_enter, NULL);
|
|
if (ret) {
|
|
pr_info("event trace: Could not activate"
|
|
"syscall entry trace point");
|
|
} else {
|
|
set_bit(num, enabled_perf_enter_syscalls);
|
|
sys_perf_refcount_enter++;
|
|
}
|
|
mutex_unlock(&syscall_trace_lock);
|
|
return ret;
|
|
}
|
|
|
|
static void perf_sysenter_disable(struct ftrace_event_call *call)
|
|
{
|
|
int num;
|
|
|
|
num = ((struct syscall_metadata *)call->data)->syscall_nr;
|
|
|
|
mutex_lock(&syscall_trace_lock);
|
|
sys_perf_refcount_enter--;
|
|
clear_bit(num, enabled_perf_enter_syscalls);
|
|
if (!sys_perf_refcount_enter)
|
|
unregister_trace_sys_enter(perf_syscall_enter, NULL);
|
|
mutex_unlock(&syscall_trace_lock);
|
|
}
|
|
|
|
static void perf_syscall_exit(void *ignore, struct pt_regs *regs, long ret)
|
|
{
|
|
struct syscall_metadata *sys_data;
|
|
struct syscall_trace_exit *rec;
|
|
struct hlist_head *head;
|
|
int syscall_nr;
|
|
int rctx;
|
|
int size;
|
|
|
|
syscall_nr = trace_get_syscall_nr(current, regs);
|
|
if (syscall_nr < 0 || syscall_nr >= NR_syscalls)
|
|
return;
|
|
if (!test_bit(syscall_nr, enabled_perf_exit_syscalls))
|
|
return;
|
|
|
|
sys_data = syscall_nr_to_meta(syscall_nr);
|
|
if (!sys_data)
|
|
return;
|
|
|
|
head = this_cpu_ptr(sys_data->exit_event->perf_events);
|
|
if (hlist_empty(head))
|
|
return;
|
|
|
|
/* We can probably do that at build time */
|
|
size = ALIGN(sizeof(*rec) + sizeof(u32), sizeof(u64));
|
|
size -= sizeof(u32);
|
|
|
|
rec = (struct syscall_trace_exit *)perf_trace_buf_prepare(size,
|
|
sys_data->exit_event->event.type, NULL, &rctx);
|
|
if (!rec)
|
|
return;
|
|
|
|
rec->nr = syscall_nr;
|
|
rec->ret = syscall_get_return_value(current, regs);
|
|
perf_trace_buf_submit(rec, size, rctx, 0, 1, regs, head, NULL);
|
|
}
|
|
|
|
static int perf_sysexit_enable(struct ftrace_event_call *call)
|
|
{
|
|
int ret = 0;
|
|
int num;
|
|
|
|
num = ((struct syscall_metadata *)call->data)->syscall_nr;
|
|
|
|
mutex_lock(&syscall_trace_lock);
|
|
if (!sys_perf_refcount_exit)
|
|
ret = register_trace_sys_exit(perf_syscall_exit, NULL);
|
|
if (ret) {
|
|
pr_info("event trace: Could not activate"
|
|
"syscall exit trace point");
|
|
} else {
|
|
set_bit(num, enabled_perf_exit_syscalls);
|
|
sys_perf_refcount_exit++;
|
|
}
|
|
mutex_unlock(&syscall_trace_lock);
|
|
return ret;
|
|
}
|
|
|
|
static void perf_sysexit_disable(struct ftrace_event_call *call)
|
|
{
|
|
int num;
|
|
|
|
num = ((struct syscall_metadata *)call->data)->syscall_nr;
|
|
|
|
mutex_lock(&syscall_trace_lock);
|
|
sys_perf_refcount_exit--;
|
|
clear_bit(num, enabled_perf_exit_syscalls);
|
|
if (!sys_perf_refcount_exit)
|
|
unregister_trace_sys_exit(perf_syscall_exit, NULL);
|
|
mutex_unlock(&syscall_trace_lock);
|
|
}
|
|
|
|
#endif /* CONFIG_PERF_EVENTS */
|
|
|
|
static int syscall_enter_register(struct ftrace_event_call *event,
|
|
enum trace_reg type, void *data)
|
|
{
|
|
struct ftrace_event_file *file = data;
|
|
|
|
switch (type) {
|
|
case TRACE_REG_REGISTER:
|
|
return reg_event_syscall_enter(file, event);
|
|
case TRACE_REG_UNREGISTER:
|
|
unreg_event_syscall_enter(file, event);
|
|
return 0;
|
|
|
|
#ifdef CONFIG_PERF_EVENTS
|
|
case TRACE_REG_PERF_REGISTER:
|
|
return perf_sysenter_enable(event);
|
|
case TRACE_REG_PERF_UNREGISTER:
|
|
perf_sysenter_disable(event);
|
|
return 0;
|
|
case TRACE_REG_PERF_OPEN:
|
|
case TRACE_REG_PERF_CLOSE:
|
|
case TRACE_REG_PERF_ADD:
|
|
case TRACE_REG_PERF_DEL:
|
|
return 0;
|
|
#endif
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int syscall_exit_register(struct ftrace_event_call *event,
|
|
enum trace_reg type, void *data)
|
|
{
|
|
struct ftrace_event_file *file = data;
|
|
|
|
switch (type) {
|
|
case TRACE_REG_REGISTER:
|
|
return reg_event_syscall_exit(file, event);
|
|
case TRACE_REG_UNREGISTER:
|
|
unreg_event_syscall_exit(file, event);
|
|
return 0;
|
|
|
|
#ifdef CONFIG_PERF_EVENTS
|
|
case TRACE_REG_PERF_REGISTER:
|
|
return perf_sysexit_enable(event);
|
|
case TRACE_REG_PERF_UNREGISTER:
|
|
perf_sysexit_disable(event);
|
|
return 0;
|
|
case TRACE_REG_PERF_OPEN:
|
|
case TRACE_REG_PERF_CLOSE:
|
|
case TRACE_REG_PERF_ADD:
|
|
case TRACE_REG_PERF_DEL:
|
|
return 0;
|
|
#endif
|
|
}
|
|
return 0;
|
|
}
|