From ed5467da0e369e65b247b99eb6403cb79172bcda Mon Sep 17 00:00:00 2001 From: Andrew Vagin Date: Fri, 2 Aug 2013 21:16:43 +0400 Subject: tracing: Fix fields of struct trace_iterator that are zeroed by mistake tracing_read_pipe zeros all fields bellow "seq". The declaration contains a comment about that, but it doesn't help. The first field is "snapshot", it's true when current open file is snapshot. Looks obvious, that it should not be zeroed. The second field is "started". It was converted from cpumask_t to cpumask_var_t (v2.6.28-4983-g4462344), in other words it was converted from cpumask to pointer on cpumask. Currently the reference on "started" memory is lost after the first read from tracing_read_pipe and a proper object will never be freed. The "started" is never dereferenced for trace_pipe, because trace_pipe can't have the TRACE_FILE_ANNOTATE options. Link: http://lkml.kernel.org/r/1375463803-3085183-1-git-send-email-avagin@openvz.org Cc: stable@vger.kernel.org # 2.6.30 Signed-off-by: Andrew Vagin Signed-off-by: Steven Rostedt --- kernel/trace/trace.c | 1 + 1 file changed, 1 insertion(+) (limited to 'kernel/trace/trace.c') diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 882ec1dd1515..f5b35a5e852f 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -4151,6 +4151,7 @@ waitagain: memset(&iter->seq, 0, sizeof(struct trace_iterator) - offsetof(struct trace_iterator, seq)); + cpumask_clear(iter->started); iter->pos = -1; trace_event_read_lock(); -- cgit v1.2.1 From 711e124379e0f889e40e2f01d7f5d61936d3cd23 Mon Sep 17 00:00:00 2001 From: Alexander Z Lam Date: Fri, 2 Aug 2013 18:36:15 -0700 Subject: tracing: Make TRACE_ITER_STOP_ON_FREE stop the correct buffer Releasing the free_buffer file in an instance causes the global buffer to be stopped when TRACE_ITER_STOP_ON_FREE is enabled. Operate on the correct buffer. Link: http://lkml.kernel.org/r/1375493777-17261-1-git-send-email-azl@google.com Cc: Vaibhav Nagarnaik Cc: David Sharp Cc: Alexander Z Lam Cc: stable@vger.kernel.org # 3.10 Signed-off-by: Alexander Z Lam Signed-off-by: Steven Rostedt --- kernel/trace/trace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel/trace/trace.c') diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index f5b35a5e852f..531c9e69d0b3 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -4469,7 +4469,7 @@ tracing_free_buffer_release(struct inode *inode, struct file *filp) /* disable tracing ? */ if (trace_flags & TRACE_ITER_STOP_ON_FREE) - tracing_off(); + tracer_tracing_off(tr); /* resize the ring buffer to 0 */ tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS); -- cgit v1.2.1 From 9457158bbc0ee04ecef76862d73eecd8076e9c7b Mon Sep 17 00:00:00 2001 From: Alexander Z Lam Date: Fri, 2 Aug 2013 18:36:16 -0700 Subject: tracing: Fix reset of time stamps during trace_clock changes Fixed two issues with changing the timestamp clock with trace_clock: - The global buffer was reset on instance clock changes. Change this to pass the correct per-instance buffer - ftrace_now() is used to set buf->time_start in tracing_reset_online_cpus(). This was incorrect because ftrace_now() used the global buffer's clock to return the current time. Change this to use buffer_ftrace_now() which returns the current time for the correct per-instance buffer. Also removed tracing_reset_current() because it is not used anywhere Link: http://lkml.kernel.org/r/1375493777-17261-2-git-send-email-azl@google.com Cc: Vaibhav Nagarnaik Cc: David Sharp Cc: Alexander Z Lam Cc: stable@vger.kernel.org # 3.10 Signed-off-by: Alexander Z Lam Signed-off-by: Steven Rostedt --- kernel/trace/trace.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) (limited to 'kernel/trace/trace.c') diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 531c9e69d0b3..496f94d57698 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -243,20 +243,25 @@ int filter_current_check_discard(struct ring_buffer *buffer, } EXPORT_SYMBOL_GPL(filter_current_check_discard); -cycle_t ftrace_now(int cpu) +cycle_t buffer_ftrace_now(struct trace_buffer *buf, int cpu) { u64 ts; /* Early boot up does not have a buffer yet */ - if (!global_trace.trace_buffer.buffer) + if (!buf->buffer) return trace_clock_local(); - ts = ring_buffer_time_stamp(global_trace.trace_buffer.buffer, cpu); - ring_buffer_normalize_time_stamp(global_trace.trace_buffer.buffer, cpu, &ts); + ts = ring_buffer_time_stamp(buf->buffer, cpu); + ring_buffer_normalize_time_stamp(buf->buffer, cpu, &ts); return ts; } +cycle_t ftrace_now(int cpu) +{ + return buffer_ftrace_now(&global_trace.trace_buffer, cpu); +} + /** * tracing_is_enabled - Show if global_trace has been disabled * @@ -1211,7 +1216,7 @@ void tracing_reset_online_cpus(struct trace_buffer *buf) /* Make sure all commits have finished */ synchronize_sched(); - buf->time_start = ftrace_now(buf->cpu); + buf->time_start = buffer_ftrace_now(buf, buf->cpu); for_each_online_cpu(cpu) ring_buffer_reset_cpu(buffer, cpu); @@ -1219,11 +1224,6 @@ void tracing_reset_online_cpus(struct trace_buffer *buf) ring_buffer_record_enable(buffer); } -void tracing_reset_current(int cpu) -{ - tracing_reset(&global_trace.trace_buffer, cpu); -} - /* Must have trace_types_lock held */ void tracing_reset_all_online_cpus(void) { @@ -4634,12 +4634,12 @@ static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, * New clock may not be consistent with the previous clock. * Reset the buffer so that it doesn't have incomparable timestamps. */ - tracing_reset_online_cpus(&global_trace.trace_buffer); + tracing_reset_online_cpus(&tr->trace_buffer); #ifdef CONFIG_TRACER_MAX_TRACE if (tr->flags & TRACE_ARRAY_FL_GLOBAL && tr->max_buffer.buffer) ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func); - tracing_reset_online_cpus(&global_trace.max_buffer); + tracing_reset_online_cpus(&tr->max_buffer); #endif mutex_unlock(&trace_types_lock); -- cgit v1.2.1