cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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auxtrace.c (3068B)

      1#include <stdbool.h>
      2#include <stdlib.h>
      3#include <linux/kernel.h>
      4#include <linux/types.h>
      5#include <linux/bitops.h>
      6#include <linux/log2.h>
      7#include <linux/zalloc.h>
      8
      9#include "../../util/evlist.h"
     10#include "../../util/auxtrace.h"
     11#include "../../util/evsel.h"
     12#include "../../util/record.h"
     13
     14#define PERF_EVENT_CPUM_SF		0xB0000 /* Event: Basic-sampling */
     15#define PERF_EVENT_CPUM_SF_DIAG		0xBD000 /* Event: Combined-sampling */
     16#define DEFAULT_AUX_PAGES		128
     17#define DEFAULT_FREQ			4000
     18
     19static void cpumsf_free(struct auxtrace_record *itr)
     20{
     21	free(itr);
     22}
     23
     24static size_t cpumsf_info_priv_size(struct auxtrace_record *itr __maybe_unused,
     25				    struct evlist *evlist __maybe_unused)
     26{
     27	return 0;
     28}
     29
     30static int
     31cpumsf_info_fill(struct auxtrace_record *itr __maybe_unused,
     32		 struct perf_session *session __maybe_unused,
     33		 struct perf_record_auxtrace_info *auxtrace_info __maybe_unused,
     34		 size_t priv_size __maybe_unused)
     35{
     36	auxtrace_info->type = PERF_AUXTRACE_S390_CPUMSF;
     37	return 0;
     38}
     39
     40static unsigned long
     41cpumsf_reference(struct auxtrace_record *itr __maybe_unused)
     42{
     43	return 0;
     44}
     45
     46static int
     47cpumsf_recording_options(struct auxtrace_record *ar __maybe_unused,
     48			 struct evlist *evlist __maybe_unused,
     49			 struct record_opts *opts)
     50{
     51	unsigned int factor = 1;
     52	unsigned int pages;
     53
     54	opts->full_auxtrace = true;
     55
     56	/*
     57	 * The AUX buffer size should be set properly to avoid
     58	 * overflow of samples if it is not set explicitly.
     59	 * DEFAULT_AUX_PAGES is an proper size when sampling frequency
     60	 * is DEFAULT_FREQ. It is expected to hold about 1/2 second
     61	 * of sampling data. The size used for AUX buffer will scale
     62	 * according to the specified frequency and DEFAULT_FREQ.
     63	 */
     64	if (!opts->auxtrace_mmap_pages) {
     65		if (opts->user_freq != UINT_MAX)
     66			factor = (opts->user_freq + DEFAULT_FREQ
     67				  - 1) / DEFAULT_FREQ;
     68		pages = DEFAULT_AUX_PAGES * factor;
     69		opts->auxtrace_mmap_pages = roundup_pow_of_two(pages);
     70	}
     71
     72	return 0;
     73}
     74
     75static int
     76cpumsf_parse_snapshot_options(struct auxtrace_record *itr __maybe_unused,
     77			      struct record_opts *opts __maybe_unused,
     78			      const char *str __maybe_unused)
     79{
     80	return 0;
     81}
     82
     83/*
     84 * auxtrace_record__init is called when perf record
     85 * check if the event really need auxtrace
     86 */
     87struct auxtrace_record *auxtrace_record__init(struct evlist *evlist,
     88					      int *err)
     89{
     90	struct auxtrace_record *aux;
     91	struct evsel *pos;
     92	int diagnose = 0;
     93
     94	*err = 0;
     95	if (evlist->core.nr_entries == 0)
     96		return NULL;
     97
     98	evlist__for_each_entry(evlist, pos) {
     99		if (pos->core.attr.config == PERF_EVENT_CPUM_SF_DIAG) {
    100			diagnose = 1;
    101			pos->needs_auxtrace_mmap = true;
    102			break;
    103		}
    104	}
    105
    106	if (!diagnose)
    107		return NULL;
    108
    109	/* sampling in diagnose mode. alloc aux buffer */
    110	aux = zalloc(sizeof(*aux));
    111	if (aux == NULL) {
    112		*err = -ENOMEM;
    113		return NULL;
    114	}
    115
    116	aux->parse_snapshot_options = cpumsf_parse_snapshot_options;
    117	aux->recording_options = cpumsf_recording_options;
    118	aux->info_priv_size = cpumsf_info_priv_size;
    119	aux->info_fill = cpumsf_info_fill;
    120	aux->free = cpumsf_free;
    121	aux->reference = cpumsf_reference;
    122
    123	return aux;
    124}