xref: /openbmc/linux/tools/perf/arch/x86/util/evsel.c (revision eb39bf325631f9ae185abd16281079b7b9858737)
1ea8d0ed6SKan Liang // SPDX-License-Identifier: GPL-2.0
2ea8d0ed6SKan Liang #include <stdio.h>
3*eb39bf32SRavi Bangoria #include <stdlib.h>
4ea8d0ed6SKan Liang #include "util/evsel.h"
5*eb39bf32SRavi Bangoria #include "util/env.h"
6*eb39bf32SRavi Bangoria #include "linux/string.h"
7ea8d0ed6SKan Liang 
8ea8d0ed6SKan Liang void arch_evsel__set_sample_weight(struct evsel *evsel)
9ea8d0ed6SKan Liang {
10ea8d0ed6SKan Liang 	evsel__set_sample_bit(evsel, WEIGHT_STRUCT);
11ea8d0ed6SKan Liang }
12*eb39bf32SRavi Bangoria 
13*eb39bf32SRavi Bangoria void arch_evsel__fixup_new_cycles(struct perf_event_attr *attr)
14*eb39bf32SRavi Bangoria {
15*eb39bf32SRavi Bangoria 	struct perf_env env = { .total_mem = 0, } ;
16*eb39bf32SRavi Bangoria 
17*eb39bf32SRavi Bangoria 	if (!perf_env__cpuid(&env))
18*eb39bf32SRavi Bangoria 		return;
19*eb39bf32SRavi Bangoria 
20*eb39bf32SRavi Bangoria 	/*
21*eb39bf32SRavi Bangoria 	 * On AMD, precise cycles event sampling internally uses IBS pmu.
22*eb39bf32SRavi Bangoria 	 * But IBS does not have filtering capabilities and perf by default
23*eb39bf32SRavi Bangoria 	 * sets exclude_guest = 1. This makes IBS pmu event init fail and
24*eb39bf32SRavi Bangoria 	 * thus perf ends up doing non-precise sampling. Avoid it by clearing
25*eb39bf32SRavi Bangoria 	 * exclude_guest.
26*eb39bf32SRavi Bangoria 	 */
27*eb39bf32SRavi Bangoria 	if (env.cpuid && strstarts(env.cpuid, "AuthenticAMD"))
28*eb39bf32SRavi Bangoria 		attr->exclude_guest = 0;
29*eb39bf32SRavi Bangoria 
30*eb39bf32SRavi Bangoria 	free(env.cpuid);
31*eb39bf32SRavi Bangoria }
32