diff options
Diffstat (limited to 'kernel/trace')
-rw-r--r-- | kernel/trace/Kconfig | 2 | ||||
-rw-r--r-- | kernel/trace/ftrace.c | 52 | ||||
-rw-r--r-- | kernel/trace/trace.h | 1 | ||||
-rw-r--r-- | kernel/trace/trace_branch.c | 17 | ||||
-rw-r--r-- | kernel/trace/trace_uprobe.c | 22 |
5 files changed, 67 insertions, 27 deletions
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index 3b9a48ae153a..1153c43428f3 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -434,7 +434,7 @@ config UPROBE_EVENT config BPF_EVENTS depends on BPF_SYSCALL - depends on KPROBE_EVENT + depends on KPROBE_EVENT || UPROBE_EVENT bool default y help diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 02bece4a99ea..eb11011b5292 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -98,6 +98,13 @@ struct ftrace_pid { struct pid *pid; }; +static bool ftrace_pids_enabled(void) +{ + return !list_empty(&ftrace_pids); +} + +static void ftrace_update_trampoline(struct ftrace_ops *ops); + /* * ftrace_disabled is set when an anomaly is discovered. * ftrace_disabled is much stronger than ftrace_enabled. @@ -109,7 +116,6 @@ static DEFINE_MUTEX(ftrace_lock); static struct ftrace_ops *ftrace_control_list __read_mostly = &ftrace_list_end; static struct ftrace_ops *ftrace_ops_list __read_mostly = &ftrace_list_end; ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub; -ftrace_func_t ftrace_pid_function __read_mostly = ftrace_stub; static struct ftrace_ops global_ops; static struct ftrace_ops control_ops; @@ -183,14 +189,7 @@ static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip, if (!test_tsk_trace_trace(current)) return; - ftrace_pid_function(ip, parent_ip, op, regs); -} - -static void set_ftrace_pid_function(ftrace_func_t func) -{ - /* do not set ftrace_pid_function to itself! */ - if (func != ftrace_pid_func) - ftrace_pid_function = func; + op->saved_func(ip, parent_ip, op, regs); } /** @@ -202,7 +201,6 @@ static void set_ftrace_pid_function(ftrace_func_t func) void clear_ftrace_function(void) { ftrace_trace_function = ftrace_stub; - ftrace_pid_function = ftrace_stub; } static void control_ops_disable_all(struct ftrace_ops *ops) @@ -436,6 +434,12 @@ static int __register_ftrace_function(struct ftrace_ops *ops) } else add_ftrace_ops(&ftrace_ops_list, ops); + /* Always save the function, and reset at unregistering */ + ops->saved_func = ops->func; + + if (ops->flags & FTRACE_OPS_FL_PID && ftrace_pids_enabled()) + ops->func = ftrace_pid_func; + ftrace_update_trampoline(ops); if (ftrace_enabled) @@ -463,15 +467,28 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops) if (ftrace_enabled) update_ftrace_function(); + ops->func = ops->saved_func; + return 0; } static void ftrace_update_pid_func(void) { + bool enabled = ftrace_pids_enabled(); + struct ftrace_ops *op; + /* Only do something if we are tracing something */ if (ftrace_trace_function == ftrace_stub) return; + do_for_each_ftrace_op(op, ftrace_ops_list) { + if (op->flags & FTRACE_OPS_FL_PID) { + op->func = enabled ? ftrace_pid_func : + op->saved_func; + ftrace_update_trampoline(op); + } + } while_for_each_ftrace_op(op); + update_ftrace_function(); } @@ -1133,7 +1150,8 @@ static struct ftrace_ops global_ops = { .local_hash.filter_hash = EMPTY_HASH, INIT_OPS_HASH(global_ops) .flags = FTRACE_OPS_FL_RECURSION_SAFE | - FTRACE_OPS_FL_INITIALIZED, + FTRACE_OPS_FL_INITIALIZED | + FTRACE_OPS_FL_PID, }; /* @@ -5023,7 +5041,9 @@ static void ftrace_update_trampoline(struct ftrace_ops *ops) static struct ftrace_ops global_ops = { .func = ftrace_stub, - .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED, + .flags = FTRACE_OPS_FL_RECURSION_SAFE | + FTRACE_OPS_FL_INITIALIZED | + FTRACE_OPS_FL_PID, }; static int __init ftrace_nodyn_init(void) @@ -5080,11 +5100,6 @@ void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func) if (WARN_ON(tr->ops->func != ftrace_stub)) printk("ftrace ops had %pS for function\n", tr->ops->func); - /* Only the top level instance does pid tracing */ - if (!list_empty(&ftrace_pids)) { - set_ftrace_pid_function(func); - func = ftrace_pid_func; - } } tr->ops->func = func; tr->ops->private = tr; @@ -5371,7 +5386,7 @@ static void *fpid_start(struct seq_file *m, loff_t *pos) { mutex_lock(&ftrace_lock); - if (list_empty(&ftrace_pids) && (!*pos)) + if (!ftrace_pids_enabled() && (!*pos)) return (void *) 1; return seq_list_start(&ftrace_pids, *pos); @@ -5610,6 +5625,7 @@ static struct ftrace_ops graph_ops = { .func = ftrace_stub, .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED | + FTRACE_OPS_FL_PID | FTRACE_OPS_FL_STUB, #ifdef FTRACE_GRAPH_TRAMP_ADDR .trampoline = FTRACE_GRAPH_TRAMP_ADDR, diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index f060716b02ae..74bde81601a9 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -444,6 +444,7 @@ enum { TRACE_CONTROL_BIT, + TRACE_BRANCH_BIT, /* * Abuse of the trace_recursion. * As we need a way to maintain state if we are tracing the function diff --git a/kernel/trace/trace_branch.c b/kernel/trace/trace_branch.c index a87b43f49eb4..e2e12ad3186f 100644 --- a/kernel/trace/trace_branch.c +++ b/kernel/trace/trace_branch.c @@ -36,9 +36,12 @@ probe_likely_condition(struct ftrace_branch_data *f, int val, int expect) struct trace_branch *entry; struct ring_buffer *buffer; unsigned long flags; - int cpu, pc; + int pc; const char *p; + if (current->trace_recursion & TRACE_BRANCH_BIT) + return; + /* * I would love to save just the ftrace_likely_data pointer, but * this code can also be used by modules. Ugly things can happen @@ -49,10 +52,10 @@ probe_likely_condition(struct ftrace_branch_data *f, int val, int expect) if (unlikely(!tr)) return; - local_irq_save(flags); - cpu = raw_smp_processor_id(); - data = per_cpu_ptr(tr->trace_buffer.data, cpu); - if (atomic_inc_return(&data->disabled) != 1) + raw_local_irq_save(flags); + current->trace_recursion |= TRACE_BRANCH_BIT; + data = this_cpu_ptr(tr->trace_buffer.data); + if (atomic_read(&data->disabled)) goto out; pc = preempt_count(); @@ -81,8 +84,8 @@ probe_likely_condition(struct ftrace_branch_data *f, int val, int expect) __buffer_unlock_commit(buffer, event); out: - atomic_dec(&data->disabled); - local_irq_restore(flags); + current->trace_recursion &= ~TRACE_BRANCH_BIT; + raw_local_irq_restore(flags); } static inline diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c index aa1ea7b36fa8..d2f6d0be3503 100644 --- a/kernel/trace/trace_uprobe.c +++ b/kernel/trace/trace_uprobe.c @@ -601,7 +601,22 @@ static int probes_seq_show(struct seq_file *m, void *v) seq_printf(m, "%c:%s/%s", c, tu->tp.call.class->system, trace_event_name(&tu->tp.call)); - seq_printf(m, " %s:0x%p", tu->filename, (void *)tu->offset); + seq_printf(m, " %s:", tu->filename); + + /* Don't print "0x (null)" when offset is 0 */ + if (tu->offset) { + seq_printf(m, "0x%p", (void *)tu->offset); + } else { + switch (sizeof(void *)) { + case 4: + seq_printf(m, "0x00000000"); + break; + case 8: + default: + seq_printf(m, "0x0000000000000000"); + break; + } + } for (i = 0; i < tu->tp.nr_args; i++) seq_printf(m, " %s=%s", tu->tp.args[i].name, tu->tp.args[i].comm); @@ -1095,11 +1110,15 @@ static void __uprobe_perf_func(struct trace_uprobe *tu, { struct trace_event_call *call = &tu->tp.call; struct uprobe_trace_entry_head *entry; + struct bpf_prog *prog = call->prog; struct hlist_head *head; void *data; int size, esize; int rctx; + if (prog && !trace_call_bpf(prog, regs)) + return; + esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu)); size = esize + tu->tp.size + dsize; @@ -1289,6 +1308,7 @@ static int register_uprobe_event(struct trace_uprobe *tu) return -ENODEV; } + call->flags = TRACE_EVENT_FL_UPROBE; call->class->reg = trace_uprobe_register; call->data = tu; ret = trace_add_event_call(call); |