From: Steven Rostedt <[email protected]> Instead of having #ifdef CONFIG_TRACER_MAX_TRACE around every access to the struct tracer's use_max_tr field, add a helper function for that access and if CONFIG_TRACER_MAX_TRACE is not configured it just returns false.
Signed-off-by: Steven Rostedt (Google) <[email protected]> --- kernel/trace/trace.c | 52 +++++++++++++++----------------------------- kernel/trace/trace.h | 12 ++++++++++ 2 files changed, 29 insertions(+), 35 deletions(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 98524d0656bf..9fbb124e87dc 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -810,7 +810,6 @@ EXPORT_SYMBOL_GPL(tracing_on); static void tracing_snapshot_instance_cond(struct trace_array *tr, void *cond_data) { - struct tracer *tracer = tr->current_trace; unsigned long flags; if (in_nmi()) { @@ -827,7 +826,7 @@ static void tracing_snapshot_instance_cond(struct trace_array *tr, } /* Note, snapshot can not be used when the tracer uses it */ - if (tracer->use_max_tr) { + if (tracer_uses_snapshot(tr->current_trace)) { trace_array_puts(tr, "*** LATENCY TRACER ACTIVE ***\n"); trace_array_puts(tr, "*** Can not use snapshot (sorry) ***\n"); return; @@ -1076,7 +1075,7 @@ int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, guard(mutex)(&trace_types_lock); - if (tr->current_trace->use_max_tr) + if (tracer_uses_snapshot(tr->current_trace)) return -EBUSY; /* @@ -1787,7 +1786,7 @@ static int run_tracer_selftest(struct tracer *type) tr->current_trace_flags = type->flags ? : type->default_flags; #ifdef CONFIG_TRACER_MAX_TRACE - if (type->use_max_tr) { + if (tracer_uses_snapshot(type)) { /* If we expanded the buffers, make sure the max is expanded too */ if (tr->ring_buffer_expanded) ring_buffer_resize(tr->snapshot_buffer.buffer, trace_buf_size, @@ -1812,7 +1811,7 @@ static int run_tracer_selftest(struct tracer *type) tracing_reset_online_cpus(&tr->array_buffer); #ifdef CONFIG_TRACER_MAX_TRACE - if (type->use_max_tr) { + if (tracer_uses_snapshot(type)) { tr->allocated_snapshot = false; /* Shrink the max buffer again */ @@ -3240,10 +3239,8 @@ static void *s_start(struct seq_file *m, loff_t *pos) } mutex_unlock(&trace_types_lock); -#ifdef CONFIG_TRACER_MAX_TRACE - if (iter->snapshot && iter->trace->use_max_tr) + if (iter->snapshot && tracer_uses_snapshot(iter->trace)) return ERR_PTR(-EBUSY); -#endif if (*pos != iter->pos) { iter->ent = NULL; @@ -3282,10 +3279,8 @@ static void s_stop(struct seq_file *m, void *p) { struct trace_iterator *iter = m->private; -#ifdef CONFIG_TRACER_MAX_TRACE - if (iter->snapshot && iter->trace->use_max_tr) + if (iter->snapshot && tracer_uses_snapshot(iter->trace)) return; -#endif trace_access_unlock(iter->cpu_file); trace_event_read_unlock(); @@ -4177,11 +4172,9 @@ static int tracing_open(struct inode *inode, struct file *file) static bool trace_ok_for_array(struct tracer *t, struct trace_array *tr) { -#ifdef CONFIG_TRACER_SNAPSHOT /* arrays with mapped buffer range do not have snapshots */ - if (tr->range_addr_start && t->use_max_tr) + if (tr->range_addr_start && tracer_uses_snapshot(t)) return false; -#endif return (tr->flags & TRACE_ARRAY_FL_GLOBAL) || t->allow_instances; } @@ -5579,8 +5572,7 @@ int tracing_set_tracer(struct trace_array *tr, const char *buf) if (trace == tr->current_trace) return 0; -#ifdef CONFIG_TRACER_SNAPSHOT - if (trace->use_max_tr) { + if (tracer_uses_snapshot(trace)) { local_irq_disable(); arch_spin_lock(&tr->max_lock); ret = tr->cond_snapshot ? -EBUSY : 0; @@ -5589,7 +5581,7 @@ int tracing_set_tracer(struct trace_array *tr, const char *buf) if (ret) return ret; } -#endif + /* Some tracers won't work on kernel command line */ if (system_state < SYSTEM_RUNNING && trace->noboot) { pr_warn("Tracer '%s' is not allowed on command line, ignored\n", @@ -5612,14 +5604,13 @@ int tracing_set_tracer(struct trace_array *tr, const char *buf) if (tr->current_trace->reset) tr->current_trace->reset(tr); -#ifdef CONFIG_TRACER_MAX_TRACE - had_max_tr = tr->current_trace->use_max_tr; + had_max_tr = tracer_uses_snapshot(tr->current_trace); /* Current trace needs to be nop_trace before synchronize_rcu */ tr->current_trace = &nop_trace; tr->current_trace_flags = nop_trace.flags; - if (had_max_tr && !trace->use_max_tr) { + if (had_max_tr && !tracer_uses_snapshot(trace)) { /* * We need to make sure that the update_max_tr sees that * current_trace changed to nop_trace to keep it from @@ -5632,24 +5623,19 @@ int tracing_set_tracer(struct trace_array *tr, const char *buf) tracing_disarm_snapshot(tr); } - if (!had_max_tr && trace->use_max_tr) { + if (!had_max_tr && tracer_uses_snapshot(trace)) { ret = tracing_arm_snapshot_locked(tr); if (ret) return ret; } -#else - tr->current_trace = &nop_trace; -#endif tr->current_trace_flags = t->flags ? : t->tracer->flags; if (trace->init) { ret = tracer_init(trace, tr); if (ret) { -#ifdef CONFIG_TRACER_MAX_TRACE - if (trace->use_max_tr) + if (tracer_uses_snapshot(trace)) tracing_disarm_snapshot(tr); -#endif tr->current_trace_flags = nop_trace.flags; return ret; } @@ -7207,7 +7193,7 @@ tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt, guard(mutex)(&trace_types_lock); - if (tr->current_trace->use_max_tr) + if (tracer_uses_snapshot(tr->current_trace)) return -EBUSY; local_irq_disable(); @@ -7306,7 +7292,7 @@ static int snapshot_raw_open(struct inode *inode, struct file *filp) info = filp->private_data; - if (info->iter.trace->use_max_tr) { + if (tracer_uses_snapshot(info->iter.trace)) { tracing_buffers_release(inode, filp); return -EBUSY; } @@ -7862,10 +7848,8 @@ tracing_buffers_read(struct file *filp, char __user *ubuf, if (!count) return 0; -#ifdef CONFIG_TRACER_MAX_TRACE - if (iter->snapshot && iter->tr->current_trace->use_max_tr) + if (iter->snapshot && tracer_uses_snapshot(iter->tr->current_trace)) return -EBUSY; -#endif page_size = ring_buffer_subbuf_size_get(iter->array_buffer->buffer); @@ -8049,10 +8033,8 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos, int entries, i; ssize_t ret = 0; -#ifdef CONFIG_TRACER_MAX_TRACE - if (iter->snapshot && iter->tr->current_trace->use_max_tr) + if (iter->snapshot && tracer_uses_snapshot(iter->tr->current_trace)) return -EBUSY; -#endif page_size = ring_buffer_subbuf_size_get(iter->array_buffer->buffer); if (*ppos & (page_size - 1)) diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index b50383aa8e50..ebb47abc0ee7 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -817,6 +817,18 @@ static inline void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, } #endif /* CONFIG_STACKTRACE */ +#ifdef CONFIG_TRACER_MAX_TRACE +static inline bool tracer_uses_snapshot(struct tracer *tracer) +{ + return tracer->use_max_tr; +} +#else +static inline bool tracer_uses_snapshot(struct tracer *tracer) +{ + return false; +} +#endif + void trace_last_func_repeats(struct trace_array *tr, struct trace_func_repeats *last_info, unsigned int trace_ctx); -- 2.51.0
