perf tools: Add hw_idx in struct branch_stack

The low level index of raw branch records for the most recent branch can
be recorded in a sample with PERF_SAMPLE_BRANCH_HW_INDEX
branch_sample_type. Extend struct branch_stack to support it.

However, if the PERF_SAMPLE_BRANCH_HW_INDEX is not applied, only nr and
entries[] will be output by kernel. The pointer of entries[] could be
wrong, since the output format is different with new struct
branch_stack.  Add a variable no_hw_idx in struct perf_sample to
indicate whether the hw_idx is output.  Add get_branch_entry() to return
corresponding pointer of entries[0].

To make dummy branch sample consistent as new branch sample, add hw_idx
in struct dummy_branch_stack for cs-etm and intel-pt.

Apply the new struct branch_stack for synthetic events as well.

Extend test case sample-parsing to support new struct branch_stack.

Committer notes:

Renamed get_branch_entries() to perf_sample__branch_entries() to have
proper namespacing and pave the way for this to be moved to libperf,
eventually.

Add 'static' to that inline as it is in a header.

Add 'hw_idx' to 'struct dummy_branch_stack' in cs-etm.c to fix the build
on arm64.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Pavel Gerasimov <pavel.gerasimov@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vitaly Slobodskoy <vitaly.slobodskoy@intel.com>
Link: http://lore.kernel.org/lkml/20200228163011.19358-2-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 6 insertions, 1 deletions

diff --git a/tools/perf/tests/sample-parsing.c b/tools/perf/tests/sample-parsing.c
index 2762e1155238..14239e472187 100644
--- a/tools/perf/tests/sample-parsing.c
+++ b/tools/perf/tests/sample-parsing.c
@@ -99,6 +99,7 @@ static bool samples_same(const struct perf_sample *s1,
 
 	if (type & PERF_SAMPLE_BRANCH_STACK) {
 		COMP(branch_stack->nr);
+		COMP(branch_stack->hw_idx);
 		for (i = 0; i < s1->branch_stack->nr; i++)
 			MCOMP(branch_stack->entries[i]);
 	}
@@ -186,7 +187,7 @@ static int do_test(u64 sample_type, u64 sample_regs, u64 read_format)
 		u64 data[64];
 	} branch_stack = {
 		/* 1 branch_entry */
-		.data = {1, 211, 212, 213},
+		.data = {1, -1ULL, 211, 212, 213},
 	};
 	u64 regs[64];
 	const u64 raw_data[] = {0x123456780a0b0c0dULL, 0x1102030405060708ULL};
@@ -208,6 +209,7 @@ static int do_test(u64 sample_type, u64 sample_regs, u64 read_format)
 		.transaction	= 112,
 		.raw_data	= (void *)raw_data,
 		.callchain	= &callchain.callchain,
+		.no_hw_idx      = false,
 		.branch_stack	= &branch_stack.branch_stack,
 		.user_regs	= {
 			.abi	= PERF_SAMPLE_REGS_ABI_64,
@@ -244,6 +246,9 @@ static int do_test(u64 sample_type, u64 sample_regs, u64 read_format)
 	if (sample_type & PERF_SAMPLE_REGS_INTR)
 		evsel.core.attr.sample_regs_intr = sample_regs;
 
+	if (sample_type & PERF_SAMPLE_BRANCH_STACK)
+		evsel.core.attr.branch_sample_type |= PERF_SAMPLE_BRANCH_HW_INDEX;
+
 	for (i = 0; i < sizeof(regs); i++)
 		*(i + (u8 *)regs) = i & 0xfe;