Some minor things that I will rework in next rev after spending some more time on it:
On Sat, Jun 3, 2017 at 9:03 PM, Joel Fernandes <joe...@google.com> wrote: [..] > @@ -463,7 +469,7 @@ int trace_set_clr_event(const char *system, const char > *event, int set); > #define event_trace_printk(ip, fmt, args...) \ > do { \ > __trace_printk_check_format(fmt, ##args); \ > - tracing_record_cmdline(current); \ > + tracing_record_taskinfo_single(current, true, false); \ > if (__builtin_constant_p(fmt)) { \ > static const char *trace_printk_fmt \ > __attribute__((section("__trace_printk_fmt"))) = \ > diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c > index 193c5f5e3f79..d7394cdf899e 100644 > --- a/kernel/trace/blktrace.c > +++ b/kernel/trace/blktrace.c > @@ -236,7 +236,7 @@ static void __blk_add_trace(struct blk_trace *bt, > sector_t sector, int bytes, > cpu = raw_smp_processor_id(); > > if (blk_tracer) { > - tracing_record_cmdline(current); > + tracing_record_taskinfo_single(current, true, false); I think I will try to preserve the existing API so that existing users aren't bothered much. > > buffer = blk_tr->trace_buffer.buffer; > pc = preempt_count(); > diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c > index 63deff9cdf2c..7be21ae4f0a8 100644 > --- a/kernel/trace/trace.c > +++ b/kernel/trace/trace.c > @@ -87,7 +87,7 @@ dummy_set_flag(struct trace_array *tr, u32 old_flags, u32 > bit, int set) > * tracing is active, only save the comm when a trace event > * occurred. > */ > -static DEFINE_PER_CPU(bool, trace_cmdline_save); > +static DEFINE_PER_CPU(bool, trace_taskinfo_save); > > /* > * Kill all tracing for good (never come back). > @@ -790,7 +790,7 @@ EXPORT_SYMBOL_GPL(tracing_on); > static __always_inline void > __buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event > *event) > { > - __this_cpu_write(trace_cmdline_save, true); > + __this_cpu_write(trace_taskinfo_save, true); > > /* If this is the temp buffer, we need to commit fully */ > if (this_cpu_read(trace_buffered_event) == event) { > @@ -1709,6 +1709,15 @@ void tracing_reset_all_online_cpus(void) > } > } > > +static unsigned int *tgid_map; > + > +void tracing_alloc_tgid_map(void) > +{ > + tgid_map = kzalloc((PID_MAX_DEFAULT + 1) * sizeof(*tgid_map), > + GFP_KERNEL); > + WARN_ONCE(!tgid_map, "Allocation of tgid_map failed\n"); I should check if tgid_map is already allocated or there's a chance of re-allocating. Looking forward to any other comments... thanks, -Joel