Commit 61d89900 authored by Kajol Jain's avatar Kajol Jain Committed by Michael Ellerman
Browse files

selftests/powerpc/pmu: Add support for branch sampling in get_intr_regs function 



Add support for sample type as PERF_SAMPLE_BRANCH_STACK in sampling
tests. This change is a precursor/helper for sampling testcases, that
test branck stack feature in perf interface.

Signed-off-by: default avatarKajol Jain <kjain@linux.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220610134113.62991-5-atrajeev@linux.vnet.ibm.com
parent 50d9c30a

tools/testing/selftests/powerpc/pmu/sampling_tests/misc.c

+20 −1
Original line number Diff line number Diff line
@@ -259,13 +259,32 @@ u64 *get_intr_regs(struct event *event, void *sample_buff) 
	u64 *intr_regs;

	size_t size = 0;



	if ((type ^ PERF_SAMPLE_REGS_INTR))

	if ((type ^ (PERF_SAMPLE_REGS_INTR | PERF_SAMPLE_BRANCH_STACK)) &&

			(type  ^ PERF_SAMPLE_REGS_INTR))

		return NULL;



	intr_regs = (u64 *)perf_read_first_sample(sample_buff, &size);

	if (!intr_regs)

		return NULL;



	if (type & PERF_SAMPLE_BRANCH_STACK) {

		/*

		 * PERF_RECORD_SAMPLE and PERF_SAMPLE_BRANCH_STACK:

		 * struct {

		 *     struct perf_event_header hdr;

		 *     u64 number_of_branches;

		 *     struct perf_branch_entry[number_of_branches];

		 *     u64 data[];

		 * };

		 * struct perf_branch_entry {

		 *     u64	from;

		 *     u64	to;

		 *     u64	misc;

		 * };

		 */

		intr_regs += ((*intr_regs) * 3) + 1;

	}



	/*

	 * First entry in the sample buffer used to specify

	 * PERF_SAMPLE_REGS_ABI_64, skip perf regs abi to access