aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorAlex Bennée <alex.bennee@linaro.org>2019-06-11 13:29:55 +0100
committerAlex Bennée <alex.bennee@linaro.org>2019-10-28 15:12:38 +0000
commit12268df393726e4edea62d36fa98b7f4ddd388c5 (patch)
treeb03400a2cd6f5f7025e58189a89146ace0121369
parentf79e8fa3b7b6226e1e17359fd8039fcf4486997e (diff)
tests/plugin: add hotpages to analyse memory access patterns
This plugin gives a summary of access patterns grouped by "pages" and showing read/write patterns by vCPUS. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
-rw-r--r--tests/plugin/Makefile1
-rw-r--r--tests/plugin/hotpages.c191
2 files changed, 192 insertions, 0 deletions
diff --git a/tests/plugin/Makefile b/tests/plugin/Makefile
index 3656429d46..75467b6db8 100644
--- a/tests/plugin/Makefile
+++ b/tests/plugin/Makefile
@@ -12,6 +12,7 @@ NAMES += insn
NAMES += mem
NAMES += hotblocks
NAMES += howvec
+NAMES += hotpages
SONAMES := $(addsuffix .so,$(addprefix lib,$(NAMES)))
diff --git a/tests/plugin/hotpages.c b/tests/plugin/hotpages.c
new file mode 100644
index 0000000000..77df07a3cc
--- /dev/null
+++ b/tests/plugin/hotpages.c
@@ -0,0 +1,191 @@
+/*
+ * Copyright (C) 2019, Alex Bennée <alex.bennee@linaro.org>
+ *
+ * Hot Pages - show which pages saw the most memory accesses.
+ *
+ * License: GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include <inttypes.h>
+#include <assert.h>
+#include <stdlib.h>
+#include <inttypes.h>
+#include <string.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <glib.h>
+
+#include <qemu-plugin.h>
+
+#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
+
+static uint64_t page_size = 4096;
+static uint64_t page_mask;
+static int limit = 50;
+static enum qemu_plugin_mem_rw rw = QEMU_PLUGIN_MEM_RW;
+static bool track_io;
+
+enum sort_type {
+ SORT_RW = 0,
+ SORT_R,
+ SORT_W,
+ SORT_A
+};
+
+static int sort_by = SORT_RW;
+
+typedef struct {
+ uint64_t page_address;
+ int cpu_read;
+ int cpu_write;
+ uint64_t reads;
+ uint64_t writes;
+} PageCounters;
+
+static GMutex lock;
+static GHashTable *pages;
+
+static gint cmp_access_count(gconstpointer a, gconstpointer b)
+{
+ PageCounters *ea = (PageCounters *) a;
+ PageCounters *eb = (PageCounters *) b;
+ int r;
+ switch (sort_by) {
+ case SORT_RW:
+ r = (ea->reads + ea->writes) > (eb->reads + eb->writes) ? -1 : 1;
+ break;
+ case SORT_R:
+ r = ea->reads > eb->reads ? -1 : 1;
+ break;
+ case SORT_W:
+ r = ea->writes > eb->writes ? -1 : 1;
+ break;
+ case SORT_A:
+ r = ea->page_address > eb->page_address ? -1 : 1;
+ break;
+ default:
+ g_assert_not_reached();
+ }
+ return r;
+}
+
+
+static void plugin_exit(qemu_plugin_id_t id, void *p)
+{
+ g_autoptr(GString) report = g_string_new("Addr, RCPUs, Reads, WCPUs, Writes\n");
+ int i;
+ GList *counts;
+
+ counts = g_hash_table_get_values(pages);
+ if (counts && g_list_next(counts)) {
+ GList *it;
+
+ it = g_list_sort(counts, cmp_access_count);
+
+ for (i = 0; i < limit && it->next; i++, it = it->next) {
+ PageCounters *rec = (PageCounters *) it->data;
+ g_string_append_printf(report,
+ "%#016"PRIx64", 0x%04x, %"PRId64
+ ", 0x%04x, %"PRId64"\n",
+ rec->page_address,
+ rec->cpu_read, rec->reads,
+ rec->cpu_write, rec->writes);
+ }
+ g_list_free(it);
+ }
+
+ qemu_plugin_outs(report->str);
+}
+
+static void plugin_init(void)
+{
+ page_mask = (page_size - 1);
+ pages = g_hash_table_new(NULL, g_direct_equal);
+}
+
+static void vcpu_haddr(unsigned int cpu_index, qemu_plugin_meminfo_t meminfo,
+ uint64_t vaddr, void *udata)
+{
+ struct qemu_plugin_hwaddr *hwaddr = qemu_plugin_get_hwaddr(meminfo, vaddr);
+ uint64_t page;
+ PageCounters *count;
+
+ /* We only get a hwaddr for system emulation */
+ if (track_io) {
+ if (hwaddr && qemu_plugin_hwaddr_is_io(hwaddr)) {
+ page = vaddr;
+ } else {
+ return;
+ }
+ } else {
+ if (hwaddr && !qemu_plugin_hwaddr_is_io(hwaddr)) {
+ page = (uint64_t) qemu_plugin_hwaddr_device_offset(hwaddr);
+ } else {
+ page = vaddr;
+ }
+ }
+ page &= ~page_mask;
+
+ g_mutex_lock(&lock);
+ count = (PageCounters *) g_hash_table_lookup(pages, GUINT_TO_POINTER(page));
+
+ if (!count) {
+ count = g_new0(PageCounters, 1);
+ count->page_address = page;
+ g_hash_table_insert(pages, GUINT_TO_POINTER(page), (gpointer) count);
+ }
+ if (qemu_plugin_mem_is_store(meminfo)) {
+ count->writes++;
+ count->cpu_write |= (1 << cpu_index);
+ } else {
+ count->reads++;
+ count->cpu_read |= (1 << cpu_index);
+ }
+
+ g_mutex_unlock(&lock);
+}
+
+static void vcpu_tb_trans(qemu_plugin_id_t id, struct qemu_plugin_tb *tb)
+{
+ size_t n = qemu_plugin_tb_n_insns(tb);
+ size_t i;
+
+ for (i = 0; i < n; i++) {
+ struct qemu_plugin_insn *insn = qemu_plugin_tb_get_insn(tb, i);
+ qemu_plugin_register_vcpu_mem_cb(insn, vcpu_haddr,
+ QEMU_PLUGIN_CB_NO_REGS,
+ rw, NULL);
+ }
+}
+
+QEMU_PLUGIN_EXPORT
+int qemu_plugin_install(qemu_plugin_id_t id, const qemu_info_t *info,
+ int argc, char **argv)
+{
+ int i;
+
+ for (i = 0; i < argc; i++) {
+ char *opt = argv[i];
+ if (g_strcmp0(opt, "reads") == 0) {
+ sort_by = SORT_R;
+ } else if (g_strcmp0(opt, "writes") == 0) {
+ sort_by = SORT_W;
+ } else if (g_strcmp0(opt, "address") == 0) {
+ sort_by = SORT_A;
+ } else if (g_strcmp0(opt, "io") == 0) {
+ track_io = true;
+ } else if (g_str_has_prefix(opt, "pagesize=")) {
+ page_size = g_ascii_strtoull(opt + 9, NULL, 10);
+ } else {
+ fprintf(stderr, "option parsing failed: %s\n", opt);
+ return -1;
+ }
+ }
+
+ plugin_init();
+
+ qemu_plugin_register_vcpu_tb_trans_cb(id, vcpu_tb_trans);
+ qemu_plugin_register_atexit_cb(id, plugin_exit, NULL);
+ return 0;
+}