+++ /dev/null
-/*
- * lttng-syscalls.c
- *
- * Copyright 2010 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- *
- * LTTng sched probes.
- *
- * Dual LGPL v2.1/GPL v2 license.
- */
-
-#include <linux/module.h>
-#include <linux/slab.h>
-#include <asm/ptrace.h>
-#include <asm/syscall.h>
-
-#include "ltt-events.h"
-
-static void syscall_entry_probe(void *__data, struct pt_regs *regs, long id);
-
-/*
- * Take care of NOARGS not supported by mainline.
- */
-#define DECLARE_EVENT_CLASS_NOARGS(name, tstruct, assign, print)
-#define DEFINE_EVENT_NOARGS(template, name)
-#define TRACE_EVENT_NOARGS(name, struct, assign, print)
-
-/*
- * Create LTTng tracepoint probes.
- */
-#define LTTNG_PACKAGE_BUILD
-#define CREATE_TRACE_POINTS
-
-/* Hijack probe callback for system calls */
-#define TP_PROBE_CB(_template) &syscall_entry_probe
-#define TP_MODULE_OVERRIDE
-
-#define TRACE_INCLUDE_PATH ../instrumentation/syscalls/headers
-#include "instrumentation/syscalls/headers/syscalls_integers.h"
-#include "instrumentation/syscalls/headers/syscalls_pointers.h"
-
-#undef TP_MODULE_OVERRIDE
-#undef TP_PROBE_CB
-#undef LTTNG_PACKAGE_BUILD
-#undef CREATE_TRACE_POINTS
-
-struct trace_syscall_entry {
- void *func;
- const struct lttng_event_desc *desc;
- const struct lttng_event_field *fields;
- unsigned int nrargs;
-};
-
-#define CREATE_SYSCALL_TABLE
-
-#undef TRACE_SYSCALL_TABLE
-#define TRACE_SYSCALL_TABLE(_template, _name, _nr, _nrargs) \
- [ _nr ] = { \
- .func = __event_probe__##_template, \
- .nrargs = (_nrargs), \
- .fields = __event_fields___##_template, \
- .desc = &__event_desc___##_name, \
- },
-
-static struct trace_syscall_entry sc_table[] = {
-#include "instrumentation/syscalls/headers/syscalls_integers.h"
-#include "instrumentation/syscalls/headers/syscalls_pointers.h"
-};
-
-#undef CREATE_SYSCALL_TABLE
-
-static void syscall_entry_probe(void *__data, struct pt_regs *regs, long id)
-{
- struct trace_syscall_entry *entry;
- struct ltt_channel *chan = __data;
- struct ltt_event *event;
-
- if (unlikely(id >= ARRAY_SIZE(sc_table)))
- return;
- entry = &sc_table[id];
- if (unlikely(!entry->func))
- return;
- event = chan->sc_table[id];
- WARN_ON_ONCE(!event);
-
- switch (entry->nrargs) {
- case 0:
- {
- void (*fptr)(void *__data) = entry->func;
-
- fptr(event);
- break;
- }
- case 1:
- {
- void (*fptr)(void *__data, unsigned long arg0) = entry->func;
- unsigned long args[1];
-
- syscall_get_arguments(current, regs, 0, entry->nrargs, args);
- fptr(event, args[0]);
- break;
- }
- case 2:
- {
- void (*fptr)(void *__data,
- unsigned long arg0,
- unsigned long arg1) = entry->func;
- unsigned long args[2];
-
- syscall_get_arguments(current, regs, 0, entry->nrargs, args);
- fptr(event, args[0], args[1]);
- break;
- }
- case 3:
- {
- void (*fptr)(void *__data,
- unsigned long arg0,
- unsigned long arg1,
- unsigned long arg2) = entry->func;
- unsigned long args[3];
-
- syscall_get_arguments(current, regs, 0, entry->nrargs, args);
- fptr(event, args[0], args[1], args[2]);
- break;
- }
- case 4:
- {
- void (*fptr)(void *__data,
- unsigned long arg0,
- unsigned long arg1,
- unsigned long arg2,
- unsigned long arg3) = entry->func;
- unsigned long args[4];
-
- syscall_get_arguments(current, regs, 0, entry->nrargs, args);
- fptr(event, args[0], args[1], args[2], args[3]);
- break;
- }
- case 5:
- {
- void (*fptr)(void *__data,
- unsigned long arg0,
- unsigned long arg1,
- unsigned long arg2,
- unsigned long arg3,
- unsigned long arg4) = entry->func;
- unsigned long args[5];
-
- syscall_get_arguments(current, regs, 0, entry->nrargs, args);
- fptr(event, args[0], args[1], args[2], args[3], args[4]);
- break;
- }
- case 6:
- {
- void (*fptr)(void *__data,
- unsigned long arg0,
- unsigned long arg1,
- unsigned long arg2,
- unsigned long arg3,
- unsigned long arg4,
- unsigned long arg5) = entry->func;
- unsigned long args[6];
-
- syscall_get_arguments(current, regs, 0, entry->nrargs, args);
- fptr(event, args[0], args[1], args[2],
- args[3], args[4], args[5]);
- break;
- }
- default:
- break;
- }
-}
-
-int lttng_syscalls_register(struct ltt_channel *chan, void *filter)
-{
- unsigned int i;
- int ret;
-
- wrapper_vmalloc_sync_all();
-
- if (!chan->sc_table) {
- /* create syscall table mapping syscall to events */
- chan->sc_table = kzalloc(sizeof(struct ltt_event *)
- * ARRAY_SIZE(sc_table), GFP_KERNEL);
- if (!chan->sc_table)
- return -ENOMEM;
- }
-
- /* Allocate events for each syscall, insert into table */
- for (i = 0; i < ARRAY_SIZE(sc_table); i++) {
- struct lttng_kernel_event ev;
- const struct lttng_event_desc *desc = sc_table[i].desc;
-
- if (!desc)
- continue;
- /*
- * Skip those already populated by previous failed
- * register for this channel.
- */
- if (chan->sc_table[i])
- continue;
- memset(&ev, 0, sizeof(ev));
- strncpy(ev.name, desc->name, LTTNG_SYM_NAME_LEN);
- ev.name[LTTNG_SYM_NAME_LEN - 1] = '\0';
- ev.instrumentation = LTTNG_KERNEL_NOOP;
- chan->sc_table[i] = ltt_event_create(chan, &ev, filter,
- desc);
- if (!chan->sc_table[i]) {
- /*
- * If something goes wrong in event registration
- * after the first one, we have no choice but to
- * leave the previous events in there, until
- * deleted by session teardown.
- */
- return -EINVAL;
- }
- }
- ret = tracepoint_probe_register("sys_enter",
- (void *) syscall_entry_probe, chan);
- return ret;
-}
-
-/*
- * Only called at session destruction.
- */
-int lttng_syscalls_unregister(struct ltt_channel *chan)
-{
- int ret;
-
- if (!chan->sc_table)
- return 0;
- ret = tracepoint_probe_unregister("sys_enter",
- (void *) syscall_entry_probe, chan);
- if (ret)
- return ret;
- /* ltt_event destroy will be performed by ltt_session_destroy() */
- kfree(chan->sc_table);
- return 0;
-}