Commit 26009592 authored by Naveen N. Rao's avatar Naveen N. Rao Committed by Michael Ellerman
Browse files

selftests/powerpc: Account for offline cpus in perf-hwbreak test 



For systemwide tests, use online cpu mask to only open events on online
cpus. This enables this test to work on systems in lower SMT modes.

Signed-off-by: default avatarNaveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/15fd447dcefd19945a7d31f0a475349f548a3603.1669096083.git.naveen.n.rao@linux.vnet.ibm.com
parent 616ad3f4

tools/testing/selftests/powerpc/ptrace/perf-hwbreak.c

+39 −6
Original line number Diff line number Diff line
@@ -17,8 +17,11 @@ 
 * Copyright (C) 2018 Michael Neuling, IBM Corporation.

 */



#define _GNU_SOURCE



#include <unistd.h>

#include <assert.h>

#include <sched.h>

#include <stdio.h>

#include <stdlib.h>

#include <signal.h>
@@ -141,8 +144,10 @@ static void disable_fds(int *fd, int n) 


static int perf_systemwide_event_open(int *fd, __u32 type, __u64 addr, __u64 len)

{

	int i, ncpus, cpu, ret = 0;

	struct rlimit rlim;

	int i = 0;

	cpu_set_t *mask;

	size_t size;



	if (getrlimit(RLIMIT_NOFILE, &rlim)) {

		perror("getrlimit");
@@ -154,16 +159,44 @@ static int perf_systemwide_event_open(int *fd, __u32 type, __u64 addr, __u64 len 
		return -1;

	}



	/* Assume online processors are 0 to nprocs for simplisity */

	for (i = 0; i < nprocs; i++) {

		fd[i] = perf_cpu_event_open(i, type, addr, len);

	ncpus = get_nprocs_conf();

	size = CPU_ALLOC_SIZE(ncpus);

	mask = CPU_ALLOC(ncpus);

	if (!mask) {

		perror("malloc");

		return -1;

	}



	CPU_ZERO_S(size, mask);



	if (sched_getaffinity(0, size, mask)) {

		perror("sched_getaffinity");

		ret = -1;

		goto done;

	}



	for (i = 0, cpu = 0; i < nprocs && cpu < ncpus; cpu++) {

		if (!CPU_ISSET_S(cpu, size, mask))

			continue;

		fd[i] = perf_cpu_event_open(cpu, type, addr, len);

		if (fd[i] < 0) {

			perror("perf_systemwide_event_open");

			close_fds(fd, i);

			return fd[i];

			ret = fd[i];

			goto done;

		}

		i++;

	}

	return 0;



	if (i < nprocs) {

		printf("Error: Number of online cpus reduced since start of test: %d < %d\n", i, nprocs);

		close_fds(fd, i);

		ret = -1;

	}



done:

	CPU_FREE(mask);

	return ret;

}



static inline bool breakpoint_test(int len)