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perf tools: Improve thread_stack__process() for trace begin / end

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thread_stack__process() is used to create call paths for database
export.  Improve the handling of trace begin / end to allow for a trace
that ends in a call.

Previously, the Intel PT decoder would indicate begin / end by a branch
from / to zero. That hides useful information, in particular when a
trace ends with a call. Before remedying that, enhance the thread stack
so that it identifies the trace end by the flag instead of by ip == 0.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/20180920130048.31432-5-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Adrian Hunter
2018-09-20 16:00:46 +03:00
committed by Arnaldo Carvalho de Melo
parent 4d60e5e36a
commit 2dcde4e152
1 changed files with 9 additions and 7 deletions
Download Patch File Download Diff File Expand all files Collapse all files

16
tools/perf/util/thread-stack.c
View File

@@ -357,7 +357,7 @@ void call_return_processor__free(struct call_return_processor *crp)
static int thread_stack__push_cp(struct thread_stack *ts, u64 ret_addr, static int thread_stack__push_cp(struct thread_stack *ts, u64 ret_addr,
u64 timestamp, u64 ref, struct call_path *cp, u64 timestamp, u64 ref, struct call_path *cp,
bool no_call) bool no_call, bool trace_end)
{ {
struct thread_stack_entry *tse; struct thread_stack_entry *tse;
int err; int err;
@@ -375,6 +375,7 @@ static int thread_stack__push_cp(struct thread_stack *ts, u64 ret_addr,
tse->branch_count = ts->branch_count; tse->branch_count = ts->branch_count;
tse->cp = cp; tse->cp = cp;
tse->no_call = no_call; tse->no_call = no_call;
tse->trace_end = trace_end;
return 0; return 0;
} }
@@ -448,7 +449,7 @@ static int thread_stack__bottom(struct thread *thread, struct thread_stack *ts,
return -ENOMEM; return -ENOMEM;
return thread_stack__push_cp(thread->ts, ip, sample->time, ref, cp, return thread_stack__push_cp(thread->ts, ip, sample->time, ref, cp,
true); true, false);
} }
static int thread_stack__no_call_return(struct thread *thread, static int thread_stack__no_call_return(struct thread *thread,
@@ -480,7 +481,7 @@ static int thread_stack__no_call_return(struct thread *thread,
if (!cp) if (!cp)
return -ENOMEM; return -ENOMEM;
return thread_stack__push_cp(ts, 0, sample->time, ref, return thread_stack__push_cp(ts, 0, sample->time, ref,
cp, true); cp, true, false);
} }
} else if (thread_stack__in_kernel(ts) && sample->ip < ks) { } else if (thread_stack__in_kernel(ts) && sample->ip < ks) {
/* Return to userspace, so pop all kernel addresses */ /* Return to userspace, so pop all kernel addresses */
@@ -505,7 +506,7 @@ static int thread_stack__no_call_return(struct thread *thread,
return -ENOMEM; return -ENOMEM;
err = thread_stack__push_cp(ts, sample->addr, sample->time, ref, cp, err = thread_stack__push_cp(ts, sample->addr, sample->time, ref, cp,
true); true, false);
if (err) if (err)
return err; return err;
@@ -525,7 +526,7 @@ static int thread_stack__trace_begin(struct thread *thread,
/* Pop trace end */ /* Pop trace end */
tse = &ts->stack[ts->cnt - 1]; tse = &ts->stack[ts->cnt - 1];
if (tse->cp->sym == NULL && tse->cp->ip == 0) { if (tse->trace_end) {
err = thread_stack__call_return(thread, ts, --ts->cnt, err = thread_stack__call_return(thread, ts, --ts->cnt,
timestamp, ref, false); timestamp, ref, false);
if (err) if (err)
@@ -554,7 +555,7 @@ static int thread_stack__trace_end(struct thread_stack *ts,
ret_addr = sample->ip + sample->insn_len; ret_addr = sample->ip + sample->insn_len;
return thread_stack__push_cp(ts, ret_addr, sample->time, ref, cp, return thread_stack__push_cp(ts, ret_addr, sample->time, ref, cp,
false); false, true);
} }
int thread_stack__process(struct thread *thread, struct comm *comm, int thread_stack__process(struct thread *thread, struct comm *comm,
@@ -604,6 +605,7 @@ int thread_stack__process(struct thread *thread, struct comm *comm,
ts->last_time = sample->time; ts->last_time = sample->time;
if (sample->flags & PERF_IP_FLAG_CALL) { if (sample->flags & PERF_IP_FLAG_CALL) {
bool trace_end = sample->flags & PERF_IP_FLAG_TRACE_END;
struct call_path_root *cpr = ts->crp->cpr; struct call_path_root *cpr = ts->crp->cpr;
struct call_path *cp; struct call_path *cp;
u64 ret_addr; u64 ret_addr;
@@ -621,7 +623,7 @@ int thread_stack__process(struct thread *thread, struct comm *comm,
if (!cp) if (!cp)
return -ENOMEM; return -ENOMEM;
err = thread_stack__push_cp(ts, ret_addr, sample->time, ref, err = thread_stack__push_cp(ts, ret_addr, sample->time, ref,
cp, false); cp, false, trace_end);
} else if (sample->flags & PERF_IP_FLAG_RETURN) { } else if (sample->flags & PERF_IP_FLAG_RETURN) {
if (!sample->ip || !sample->addr) if (!sample->ip || !sample->addr)
return 0; return 0;