* [PULL 01/18] deprecation: don't enable TCG plugins by default on 32 bit hosts
2024-09-18 21:06 [PULL 00/18] tcg plugins (deprecations, mem apis, contrib plugins) Alex Bennée
@ 2024-09-18 21:06 ` Alex Bennée
2024-09-18 21:06 ` [PULL 02/18] deprecation: don't enable TCG plugins by default with TCI Alex Bennée
` (17 subsequent siblings)
18 siblings, 0 replies; 23+ messages in thread
From: Alex Bennée @ 2024-09-18 21:06 UTC (permalink / raw)
To: qemu-devel
Cc: Alex Bennée, Pierrick Bouvier, Paolo Bonzini, Thomas Huth,
reviewer:Incompatible changes
The existing plugins already liberally use host pointer stuffing for
passing user data which will fail when doing 64 bit guests on 32 bit
hosts. We should discourage this by officially deprecating support and
adding another nail to the 32 bit host coffin.
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240916085400.1046925-2-alex.bennee@linaro.org>
diff --git a/docs/about/deprecated.rst b/docs/about/deprecated.rst
index ed31d4b0b2..809b2b9b81 100644
--- a/docs/about/deprecated.rst
+++ b/docs/about/deprecated.rst
@@ -184,6 +184,17 @@ be an effective use of its limited resources, and thus intends to discontinue
it. Since all recent x86 hardware from the past >10 years is capable of the
64-bit x86 extensions, a corresponding 64-bit OS should be used instead.
+TCG Plugin support not enabled by default on 32-bit hosts (since 9.2)
+'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
+
+While it is still possible to enable TCG plugin support for 32-bit
+hosts there are a number of potential pitfalls when instrumenting
+64-bit guests. The plugin APIs typically pass most addresses as
+uint64_t but practices like encoding that address in a host pointer
+for passing as user-data will lose data. As most software analysis
+benefits from having plenty of host memory it seems reasonable to
+encourage users to use 64 bit builds of QEMU for analysis work
+whatever targets they are instrumenting.
System emulator CPUs
--------------------
diff --git a/configure b/configure
index f3e7572afb..cc8e1ed5b8 100755
--- a/configure
+++ b/configure
@@ -516,6 +516,25 @@ case "$cpu" in
;;
esac
+# Now we have our CPU_CFLAGS we can check if we are targeting a 32 or
+# 64 bit host.
+
+check_64bit_host() {
+cat > $TMPC <<EOF
+#if __SIZEOF_POINTER__ != 8
+#error not 64 bit system
+#endif
+int main(void) { return 0; }
+EOF
+ compile_object "$1"
+}
+
+if check_64bit_host "$CPU_CFLAGS"; then
+ host_bits=64
+else
+ host_bits=32
+fi
+
if test -n "$host_arch" && {
! test -d "$source_path/linux-user/include/host/$host_arch" ||
! test -d "$source_path/common-user/host/$host_arch"; }; then
@@ -1028,7 +1047,7 @@ if test "$static" = "yes" ; then
fi
plugins="no"
fi
-if test "$plugins" != "no"; then
+if test "$plugins" != "no" && test $host_bits -eq 64; then
plugins=yes
subdirs="$subdirs contrib/plugins"
fi
--
2.39.5
^ permalink raw reply related [flat|nested] 23+ messages in thread* [PULL 02/18] deprecation: don't enable TCG plugins by default with TCI
2024-09-18 21:06 [PULL 00/18] tcg plugins (deprecations, mem apis, contrib plugins) Alex Bennée
2024-09-18 21:06 ` [PULL 01/18] deprecation: don't enable TCG plugins by default on 32 bit hosts Alex Bennée
@ 2024-09-18 21:06 ` Alex Bennée
2024-09-18 21:06 ` [PULL 03/18] contrib/plugins: control flow plugin Alex Bennée
` (16 subsequent siblings)
18 siblings, 0 replies; 23+ messages in thread
From: Alex Bennée @ 2024-09-18 21:06 UTC (permalink / raw)
To: qemu-devel
Cc: Alex Bennée, Pierrick Bouvier, Paolo Bonzini, Thomas Huth,
reviewer:Incompatible changes
The softmmu memory instrumentation test sees so many more accesses
than a normal translated host and its really not worth fixing up. Lets
deprecate this odd configuration and save on the CI cycles.
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240916085400.1046925-3-alex.bennee@linaro.org>
diff --git a/docs/about/deprecated.rst b/docs/about/deprecated.rst
index 809b2b9b81..c0aa52def5 100644
--- a/docs/about/deprecated.rst
+++ b/docs/about/deprecated.rst
@@ -196,6 +196,14 @@ benefits from having plenty of host memory it seems reasonable to
encourage users to use 64 bit builds of QEMU for analysis work
whatever targets they are instrumenting.
+TCG Plugin support not enabled by default with TCI (since 9.2)
+''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
+
+While the TCG interpreter can interpret the TCG ops used by plugins it
+is going to be so much slower it wouldn't make sense for any serious
+instrumentation. Due to implementation differences there will also be
+anomalies in things like memory instrumentation.
+
System emulator CPUs
--------------------
diff --git a/configure b/configure
index cc8e1ed5b8..aa7aae70fa 100755
--- a/configure
+++ b/configure
@@ -629,6 +629,9 @@ meson_option_parse() {
exit 1
fi
}
+has_meson_option() {
+ test "${meson_options#*"$1"}" != "$meson_options"
+}
meson_add_machine_file() {
if test "$cross_compile" = "yes"; then
@@ -1048,8 +1051,12 @@ if test "$static" = "yes" ; then
plugins="no"
fi
if test "$plugins" != "no" && test $host_bits -eq 64; then
- plugins=yes
- subdirs="$subdirs contrib/plugins"
+ if has_meson_option "-Dtcg_interpreter=true"; then
+ plugins="no"
+ else
+ plugins=yes
+ subdirs="$subdirs contrib/plugins"
+ fi
fi
cat > $TMPC << EOF
--
2.39.5
^ permalink raw reply related [flat|nested] 23+ messages in thread* [PULL 03/18] contrib/plugins: control flow plugin
2024-09-18 21:06 [PULL 00/18] tcg plugins (deprecations, mem apis, contrib plugins) Alex Bennée
2024-09-18 21:06 ` [PULL 01/18] deprecation: don't enable TCG plugins by default on 32 bit hosts Alex Bennée
2024-09-18 21:06 ` [PULL 02/18] deprecation: don't enable TCG plugins by default with TCI Alex Bennée
@ 2024-09-18 21:06 ` Alex Bennée
2024-09-18 21:06 ` [PULL 04/18] plugins: save value during memory accesses Alex Bennée
` (15 subsequent siblings)
18 siblings, 0 replies; 23+ messages in thread
From: Alex Bennée @ 2024-09-18 21:06 UTC (permalink / raw)
To: qemu-devel
Cc: Alex Bennée, Pierrick Bouvier, Alexandre Iooss,
Mahmoud Mandour
This is a simple control flow tracking plugin that uses the latest
inline and conditional operations to detect and track control flow
changes. It is currently an exercise at seeing how useful the changes
are.
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240916085400.1046925-4-alex.bennee@linaro.org>
diff --git a/contrib/plugins/cflow.c b/contrib/plugins/cflow.c
new file mode 100644
index 0000000000..6faa55d10d
--- /dev/null
+++ b/contrib/plugins/cflow.c
@@ -0,0 +1,388 @@
+/*
+ * Control Flow plugin
+ *
+ * This plugin will track changes to control flow and detect where
+ * instructions fault.
+ *
+ * Copyright (c) 2024 Linaro Ltd
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#include <glib.h>
+#include <inttypes.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <qemu-plugin.h>
+
+QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION;
+
+typedef enum {
+ SORT_HOTTEST, /* hottest branch insn */
+ SORT_EXCEPTION, /* most early exits */
+ SORT_POPDEST, /* most destinations (usually ret's) */
+} ReportType;
+
+ReportType report = SORT_HOTTEST;
+int topn = 10;
+
+typedef struct {
+ uint64_t daddr;
+ uint64_t dcount;
+} DestData;
+
+/* A node is an address where we can go to multiple places */
+typedef struct {
+ GMutex lock;
+ /* address of the branch point */
+ uint64_t addr;
+ /* array of DestData */
+ GArray *dests;
+ /* early exit/fault count */
+ uint64_t early_exit;
+ /* jump destination count */
+ uint64_t dest_count;
+ /* instruction data */
+ char *insn_disas;
+ /* symbol? */
+ const char *symbol;
+ /* times translated as last in block? */
+ int last_count;
+ /* times translated in the middle of block? */
+ int mid_count;
+} NodeData;
+
+typedef enum {
+ /* last insn in block, expected flow control */
+ LAST_INSN = (1 << 0),
+ /* mid-block insn, can only be an exception */
+ EXCP_INSN = (1 << 1),
+ /* multiple disassembly, may have changed */
+ MULT_INSN = (1 << 2),
+} InsnTypes;
+
+typedef struct {
+ /* address of the branch point */
+ uint64_t addr;
+ /* disassembly */
+ char *insn_disas;
+ /* symbol? */
+ const char *symbol;
+ /* types */
+ InsnTypes type_flag;
+} InsnData;
+
+/* We use this to track the current execution state */
+typedef struct {
+ /* address of end of block */
+ uint64_t end_block;
+ /* next pc after end of block */
+ uint64_t pc_after_block;
+ /* address of last executed PC */
+ uint64_t last_pc;
+} VCPUScoreBoard;
+
+/* descriptors for accessing the above scoreboard */
+static qemu_plugin_u64 end_block;
+static qemu_plugin_u64 pc_after_block;
+static qemu_plugin_u64 last_pc;
+
+
+static GMutex node_lock;
+static GHashTable *nodes;
+struct qemu_plugin_scoreboard *state;
+
+/* SORT_HOTTEST */
+static gint hottest(gconstpointer a, gconstpointer b)
+{
+ NodeData *na = (NodeData *) a;
+ NodeData *nb = (NodeData *) b;
+
+ return na->dest_count > nb->dest_count ? -1 :
+ na->dest_count == nb->dest_count ? 0 : 1;
+}
+
+static gint exception(gconstpointer a, gconstpointer b)
+{
+ NodeData *na = (NodeData *) a;
+ NodeData *nb = (NodeData *) b;
+
+ return na->early_exit > nb->early_exit ? -1 :
+ na->early_exit == nb->early_exit ? 0 : 1;
+}
+
+static gint popular(gconstpointer a, gconstpointer b)
+{
+ NodeData *na = (NodeData *) a;
+ NodeData *nb = (NodeData *) b;
+
+ return na->dests->len > nb->dests->len ? -1 :
+ na->dests->len == nb->dests->len ? 0 : 1;
+}
+
+/* Filter out non-branches - returns true to remove entry */
+static gboolean filter_non_branches(gpointer key, gpointer value,
+ gpointer user_data)
+{
+ NodeData *node = (NodeData *) value;
+
+ return node->dest_count == 0;
+}
+
+static void plugin_exit(qemu_plugin_id_t id, void *p)
+{
+ g_autoptr(GString) result = g_string_new("collected ");
+ GList *data;
+ GCompareFunc sort = &hottest;
+ int n = 0;
+
+ g_mutex_lock(&node_lock);
+ g_string_append_printf(result, "%d control flow nodes in the hash table\n",
+ g_hash_table_size(nodes));
+
+ /* remove all nodes that didn't branch */
+ g_hash_table_foreach_remove(nodes, filter_non_branches, NULL);
+
+ data = g_hash_table_get_values(nodes);
+
+ switch (report) {
+ case SORT_HOTTEST:
+ sort = &hottest;
+ break;
+ case SORT_EXCEPTION:
+ sort = &exception;
+ break;
+ case SORT_POPDEST:
+ sort = &popular;
+ break;
+ }
+
+ data = g_list_sort(data, sort);
+
+ for (GList *l = data;
+ l != NULL && n < topn;
+ l = l->next, n++) {
+ NodeData *n = l->data;
+ const char *type = n->mid_count ? "sync fault" : "branch";
+ g_string_append_printf(result, " addr: 0x%"PRIx64 " %s: %s (%s)\n",
+ n->addr, n->symbol, n->insn_disas, type);
+ if (n->early_exit) {
+ g_string_append_printf(result, " early exits %"PRId64"\n",
+ n->early_exit);
+ }
+ g_string_append_printf(result, " branches %"PRId64"\n",
+ n->dest_count);
+ for (int j = 0; j < n->dests->len; j++) {
+ DestData *dd = &g_array_index(n->dests, DestData, j);
+ g_string_append_printf(result, " to 0x%"PRIx64" (%"PRId64")\n",
+ dd->daddr, dd->dcount);
+ }
+ }
+
+ qemu_plugin_outs(result->str);
+
+ g_mutex_unlock(&node_lock);
+}
+
+static void plugin_init(void)
+{
+ g_mutex_init(&node_lock);
+ nodes = g_hash_table_new(NULL, g_direct_equal);
+ state = qemu_plugin_scoreboard_new(sizeof(VCPUScoreBoard));
+
+ /* score board declarations */
+ end_block = qemu_plugin_scoreboard_u64_in_struct(state, VCPUScoreBoard,
+ end_block);
+ pc_after_block = qemu_plugin_scoreboard_u64_in_struct(state, VCPUScoreBoard,
+ pc_after_block);
+ last_pc = qemu_plugin_scoreboard_u64_in_struct(state, VCPUScoreBoard,
+ last_pc);
+}
+
+static NodeData *create_node(uint64_t addr)
+{
+ NodeData *node = g_new0(NodeData, 1);
+ g_mutex_init(&node->lock);
+ node->addr = addr;
+ node->dests = g_array_new(true, true, sizeof(DestData));
+ return node;
+}
+
+static NodeData *fetch_node(uint64_t addr, bool create_if_not_found)
+{
+ NodeData *node = NULL;
+
+ g_mutex_lock(&node_lock);
+ node = (NodeData *) g_hash_table_lookup(nodes, (gconstpointer) addr);
+ if (!node && create_if_not_found) {
+ node = create_node(addr);
+ g_hash_table_insert(nodes, (gpointer) addr, (gpointer) node);
+ }
+ g_mutex_unlock(&node_lock);
+ return node;
+}
+
+/*
+ * Called when we detect a non-linear execution (pc !=
+ * pc_after_block). This could be due to a fault causing some sort of
+ * exit exception (if last_pc != block_end) or just a taken branch.
+ */
+static void vcpu_tb_branched_exec(unsigned int cpu_index, void *udata)
+{
+ uint64_t lpc = qemu_plugin_u64_get(last_pc, cpu_index);
+ uint64_t ebpc = qemu_plugin_u64_get(end_block, cpu_index);
+ uint64_t npc = qemu_plugin_u64_get(pc_after_block, cpu_index);
+ uint64_t pc = GPOINTER_TO_UINT(udata);
+
+ /* return early for address 0 */
+ if (!lpc) {
+ return;
+ }
+
+ NodeData *node = fetch_node(lpc, true);
+ DestData *data = NULL;
+ bool early_exit = (lpc != ebpc);
+ GArray *dests;
+
+ /* the condition should never hit */
+ g_assert(pc != npc);
+
+ g_mutex_lock(&node->lock);
+
+ if (early_exit) {
+ fprintf(stderr, "%s: pc=%"PRIx64", epbc=%"PRIx64
+ " npc=%"PRIx64", lpc=%"PRIx64"\n",
+ __func__, pc, ebpc, npc, lpc);
+ node->early_exit++;
+ if (!node->mid_count) {
+ /* count now as we've only just allocated */
+ node->mid_count++;
+ }
+ }
+
+ dests = node->dests;
+ for (int i = 0; i < dests->len; i++) {
+ if (g_array_index(dests, DestData, i).daddr == pc) {
+ data = &g_array_index(dests, DestData, i);
+ }
+ }
+
+ /* we've never seen this before, allocate a new entry */
+ if (!data) {
+ DestData new_entry = { .daddr = pc };
+ g_array_append_val(dests, new_entry);
+ data = &g_array_index(dests, DestData, dests->len - 1);
+ g_assert(data->daddr == pc);
+ }
+
+ data->dcount++;
+ node->dest_count++;
+
+ g_mutex_unlock(&node->lock);
+}
+
+/*
+ * At the start of each block we need to resolve two things:
+ *
+ * - is last_pc == block_end, if not we had an early exit
+ * - is start of block last_pc + insn width, if not we jumped
+ *
+ * Once those are dealt with we can instrument the rest of the
+ * instructions for their execution.
+ *
+ */
+static void vcpu_tb_trans(qemu_plugin_id_t id, struct qemu_plugin_tb *tb)
+{
+ uint64_t pc = qemu_plugin_tb_vaddr(tb);
+ size_t insns = qemu_plugin_tb_n_insns(tb);
+ struct qemu_plugin_insn *first_insn = qemu_plugin_tb_get_insn(tb, 0);
+ struct qemu_plugin_insn *last_insn = qemu_plugin_tb_get_insn(tb, insns - 1);
+
+ /*
+ * check if we are executing linearly after the last block. We can
+ * handle both early block exits and normal branches in the
+ * callback if we hit it.
+ */
+ gpointer udata = GUINT_TO_POINTER(pc);
+ qemu_plugin_register_vcpu_tb_exec_cond_cb(
+ tb, vcpu_tb_branched_exec, QEMU_PLUGIN_CB_NO_REGS,
+ QEMU_PLUGIN_COND_NE, pc_after_block, pc, udata);
+
+ /*
+ * Now we can set start/end for this block so the next block can
+ * check where we are at. Do this on the first instruction and not
+ * the TB so we don't get mixed up with above.
+ */
+ qemu_plugin_register_vcpu_insn_exec_inline_per_vcpu(first_insn,
+ QEMU_PLUGIN_INLINE_STORE_U64,
+ end_block, qemu_plugin_insn_vaddr(last_insn));
+ qemu_plugin_register_vcpu_insn_exec_inline_per_vcpu(first_insn,
+ QEMU_PLUGIN_INLINE_STORE_U64,
+ pc_after_block,
+ qemu_plugin_insn_vaddr(last_insn) +
+ qemu_plugin_insn_size(last_insn));
+
+ for (int idx = 0; idx < qemu_plugin_tb_n_insns(tb); ++idx) {
+ struct qemu_plugin_insn *insn = qemu_plugin_tb_get_insn(tb, idx);
+ uint64_t ipc = qemu_plugin_insn_vaddr(insn);
+ /*
+ * If this is a potential branch point check if we could grab
+ * the disassembly for it. If it is the last instruction
+ * always create an entry.
+ */
+ NodeData *node = fetch_node(ipc, last_insn);
+ if (node) {
+ g_mutex_lock(&node->lock);
+ if (!node->insn_disas) {
+ node->insn_disas = qemu_plugin_insn_disas(insn);
+ }
+ if (!node->symbol) {
+ node->symbol = qemu_plugin_insn_symbol(insn);
+ }
+ if (last_insn == insn) {
+ node->last_count++;
+ } else {
+ node->mid_count++;
+ }
+ g_mutex_unlock(&node->lock);
+ }
+
+ /* Store the PC of what we are about to execute */
+ qemu_plugin_register_vcpu_insn_exec_inline_per_vcpu(insn,
+ QEMU_PLUGIN_INLINE_STORE_U64,
+ last_pc, ipc);
+ }
+}
+
+QEMU_PLUGIN_EXPORT
+int qemu_plugin_install(qemu_plugin_id_t id, const qemu_info_t *info,
+ int argc, char **argv)
+{
+ for (int i = 0; i < argc; i++) {
+ char *opt = argv[i];
+ g_auto(GStrv) tokens = g_strsplit(opt, "=", 2);
+ if (g_strcmp0(tokens[0], "sort") == 0) {
+ if (g_strcmp0(tokens[1], "hottest") == 0) {
+ report = SORT_HOTTEST;
+ } else if (g_strcmp0(tokens[1], "early") == 0) {
+ report = SORT_EXCEPTION;
+ } else if (g_strcmp0(tokens[1], "exceptions") == 0) {
+ report = SORT_POPDEST;
+ } else {
+ fprintf(stderr, "failed to parse: %s\n", tokens[1]);
+ return -1;
+ }
+ } 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;
+}
diff --git a/contrib/plugins/Makefile b/contrib/plugins/Makefile
index 05a2a45c5c..d4ac599f93 100644
--- a/contrib/plugins/Makefile
+++ b/contrib/plugins/Makefile
@@ -29,6 +29,7 @@ NAMES += cache
NAMES += drcov
NAMES += ips
NAMES += stoptrigger
+NAMES += cflow
ifeq ($(CONFIG_WIN32),y)
SO_SUFFIX := .dll
--
2.39.5
^ permalink raw reply related [flat|nested] 23+ messages in thread* [PULL 04/18] plugins: save value during memory accesses
2024-09-18 21:06 [PULL 00/18] tcg plugins (deprecations, mem apis, contrib plugins) Alex Bennée
` (2 preceding siblings ...)
2024-09-18 21:06 ` [PULL 03/18] contrib/plugins: control flow plugin Alex Bennée
@ 2024-09-18 21:06 ` Alex Bennée
2024-09-18 21:06 ` [PULL 05/18] plugins: extend API to get latest memory value accessed Alex Bennée
` (14 subsequent siblings)
18 siblings, 0 replies; 23+ messages in thread
From: Alex Bennée @ 2024-09-18 21:06 UTC (permalink / raw)
To: qemu-devel
Cc: Pierrick Bouvier, Richard Henderson, Alex Bennée,
Paolo Bonzini, Eduardo Habkost, Marcel Apfelbaum,
Philippe Mathieu-Daudé, Yanan Wang, Zhao Liu,
Alexandre Iooss, Mahmoud Mandour
From: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Different code paths handle memory accesses:
- tcg generated code
- load/store helpers
- atomic helpers
This value is saved in cpu->neg.plugin_mem_value_{high,low}. Values are
written only for accessed word size (upper bits are not set).
Atomic operations are doing read/write at the same time, so we generate
two memory callbacks instead of one, to allow plugins to access distinct
values.
For now, we can have access only up to 128 bits, thus split this in two
64 bits words. When QEMU will support wider operations, we'll be able to
reconsider this.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Message-Id: <20240724194708.1843704-2-pierrick.bouvier@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240916085400.1046925-5-alex.bennee@linaro.org>
diff --git a/accel/tcg/atomic_template.h b/accel/tcg/atomic_template.h
index 1dc2151daf..89593b2502 100644
--- a/accel/tcg/atomic_template.h
+++ b/accel/tcg/atomic_template.h
@@ -53,6 +53,14 @@
# error unsupported data size
#endif
+#if DATA_SIZE == 16
+# define VALUE_LOW(val) int128_getlo(val)
+# define VALUE_HIGH(val) int128_gethi(val)
+#else
+# define VALUE_LOW(val) val
+# define VALUE_HIGH(val) 0
+#endif
+
#if DATA_SIZE >= 4
# define ABI_TYPE DATA_TYPE
#else
@@ -83,7 +91,12 @@ ABI_TYPE ATOMIC_NAME(cmpxchg)(CPUArchState *env, abi_ptr addr,
ret = qatomic_cmpxchg__nocheck(haddr, cmpv, newv);
#endif
ATOMIC_MMU_CLEANUP;
- atomic_trace_rmw_post(env, addr, oi);
+ atomic_trace_rmw_post(env, addr,
+ VALUE_LOW(ret),
+ VALUE_HIGH(ret),
+ VALUE_LOW(newv),
+ VALUE_HIGH(newv),
+ oi);
return ret;
}
@@ -97,7 +110,12 @@ ABI_TYPE ATOMIC_NAME(xchg)(CPUArchState *env, abi_ptr addr, ABI_TYPE val,
ret = qatomic_xchg__nocheck(haddr, val);
ATOMIC_MMU_CLEANUP;
- atomic_trace_rmw_post(env, addr, oi);
+ atomic_trace_rmw_post(env, addr,
+ VALUE_LOW(ret),
+ VALUE_HIGH(ret),
+ VALUE_LOW(val),
+ VALUE_HIGH(val),
+ oi);
return ret;
}
@@ -109,7 +127,12 @@ ABI_TYPE ATOMIC_NAME(X)(CPUArchState *env, abi_ptr addr, \
haddr = atomic_mmu_lookup(env_cpu(env), addr, oi, DATA_SIZE, retaddr); \
ret = qatomic_##X(haddr, val); \
ATOMIC_MMU_CLEANUP; \
- atomic_trace_rmw_post(env, addr, oi); \
+ atomic_trace_rmw_post(env, addr, \
+ VALUE_LOW(ret), \
+ VALUE_HIGH(ret), \
+ VALUE_LOW(val), \
+ VALUE_HIGH(val), \
+ oi); \
return ret; \
}
@@ -145,7 +168,12 @@ ABI_TYPE ATOMIC_NAME(X)(CPUArchState *env, abi_ptr addr, \
cmp = qatomic_cmpxchg__nocheck(haddr, old, new); \
} while (cmp != old); \
ATOMIC_MMU_CLEANUP; \
- atomic_trace_rmw_post(env, addr, oi); \
+ atomic_trace_rmw_post(env, addr, \
+ VALUE_LOW(old), \
+ VALUE_HIGH(old), \
+ VALUE_LOW(xval), \
+ VALUE_HIGH(xval), \
+ oi); \
return RET; \
}
@@ -188,7 +216,12 @@ ABI_TYPE ATOMIC_NAME(cmpxchg)(CPUArchState *env, abi_ptr addr,
ret = qatomic_cmpxchg__nocheck(haddr, BSWAP(cmpv), BSWAP(newv));
#endif
ATOMIC_MMU_CLEANUP;
- atomic_trace_rmw_post(env, addr, oi);
+ atomic_trace_rmw_post(env, addr,
+ VALUE_LOW(ret),
+ VALUE_HIGH(ret),
+ VALUE_LOW(newv),
+ VALUE_HIGH(newv),
+ oi);
return BSWAP(ret);
}
@@ -202,7 +235,12 @@ ABI_TYPE ATOMIC_NAME(xchg)(CPUArchState *env, abi_ptr addr, ABI_TYPE val,
ret = qatomic_xchg__nocheck(haddr, BSWAP(val));
ATOMIC_MMU_CLEANUP;
- atomic_trace_rmw_post(env, addr, oi);
+ atomic_trace_rmw_post(env, addr,
+ VALUE_LOW(ret),
+ VALUE_HIGH(ret),
+ VALUE_LOW(val),
+ VALUE_HIGH(val),
+ oi);
return BSWAP(ret);
}
@@ -214,7 +252,12 @@ ABI_TYPE ATOMIC_NAME(X)(CPUArchState *env, abi_ptr addr, \
haddr = atomic_mmu_lookup(env_cpu(env), addr, oi, DATA_SIZE, retaddr); \
ret = qatomic_##X(haddr, BSWAP(val)); \
ATOMIC_MMU_CLEANUP; \
- atomic_trace_rmw_post(env, addr, oi); \
+ atomic_trace_rmw_post(env, addr, \
+ VALUE_LOW(ret), \
+ VALUE_HIGH(ret), \
+ VALUE_LOW(val), \
+ VALUE_HIGH(val), \
+ oi); \
return BSWAP(ret); \
}
@@ -247,7 +290,12 @@ ABI_TYPE ATOMIC_NAME(X)(CPUArchState *env, abi_ptr addr, \
ldn = qatomic_cmpxchg__nocheck(haddr, ldo, BSWAP(new)); \
} while (ldo != ldn); \
ATOMIC_MMU_CLEANUP; \
- atomic_trace_rmw_post(env, addr, oi); \
+ atomic_trace_rmw_post(env, addr, \
+ VALUE_LOW(old), \
+ VALUE_HIGH(old), \
+ VALUE_LOW(xval), \
+ VALUE_HIGH(xval), \
+ oi); \
return RET; \
}
@@ -281,3 +329,5 @@ GEN_ATOMIC_HELPER_FN(add_fetch, ADD, DATA_TYPE, new)
#undef SUFFIX
#undef DATA_SIZE
#undef SHIFT
+#undef VALUE_LOW
+#undef VALUE_HIGH
diff --git a/include/hw/core/cpu.h b/include/hw/core/cpu.h
index 1c9c775df6..04e9ad4996 100644
--- a/include/hw/core/cpu.h
+++ b/include/hw/core/cpu.h
@@ -350,6 +350,8 @@ typedef union IcountDecr {
* from CPUArchState, via small negative offsets.
* @can_do_io: True if memory-mapped IO is allowed.
* @plugin_mem_cbs: active plugin memory callbacks
+ * @plugin_mem_value_low: 64 lower bits of latest accessed mem value.
+ * @plugin_mem_value_high: 64 higher bits of latest accessed mem value.
*/
typedef struct CPUNegativeOffsetState {
CPUTLB tlb;
@@ -358,6 +360,8 @@ typedef struct CPUNegativeOffsetState {
* The callback pointer are accessed via TCG (see gen_empty_mem_helper).
*/
GArray *plugin_mem_cbs;
+ uint64_t plugin_mem_value_low;
+ uint64_t plugin_mem_value_high;
#endif
IcountDecr icount_decr;
bool can_do_io;
diff --git a/include/qemu/plugin.h b/include/qemu/plugin.h
index af5f9db469..9726a9ebf3 100644
--- a/include/qemu/plugin.h
+++ b/include/qemu/plugin.h
@@ -167,6 +167,8 @@ qemu_plugin_vcpu_syscall(CPUState *cpu, int64_t num, uint64_t a1,
void qemu_plugin_vcpu_syscall_ret(CPUState *cpu, int64_t num, int64_t ret);
void qemu_plugin_vcpu_mem_cb(CPUState *cpu, uint64_t vaddr,
+ uint64_t value_low,
+ uint64_t value_high,
MemOpIdx oi, enum qemu_plugin_mem_rw rw);
void qemu_plugin_flush_cb(void);
@@ -251,6 +253,8 @@ void qemu_plugin_vcpu_syscall_ret(CPUState *cpu, int64_t num, int64_t ret)
{ }
static inline void qemu_plugin_vcpu_mem_cb(CPUState *cpu, uint64_t vaddr,
+ uint64_t value_low,
+ uint64_t value_high,
MemOpIdx oi,
enum qemu_plugin_mem_rw rw)
{ }
diff --git a/plugins/core.c b/plugins/core.c
index 2897453cac..bb105e8e68 100644
--- a/plugins/core.c
+++ b/plugins/core.c
@@ -602,6 +602,8 @@ void exec_inline_op(enum plugin_dyn_cb_type type,
}
void qemu_plugin_vcpu_mem_cb(CPUState *cpu, uint64_t vaddr,
+ uint64_t value_low,
+ uint64_t value_high,
MemOpIdx oi, enum qemu_plugin_mem_rw rw)
{
GArray *arr = cpu->neg.plugin_mem_cbs;
@@ -610,6 +612,10 @@ void qemu_plugin_vcpu_mem_cb(CPUState *cpu, uint64_t vaddr,
if (arr == NULL) {
return;
}
+
+ cpu->neg.plugin_mem_value_low = value_low;
+ cpu->neg.plugin_mem_value_high = value_high;
+
for (i = 0; i < arr->len; i++) {
struct qemu_plugin_dyn_cb *cb =
&g_array_index(arr, struct qemu_plugin_dyn_cb, i);
diff --git a/tcg/tcg-op-ldst.c b/tcg/tcg-op-ldst.c
index 8510160258..23dc807f11 100644
--- a/tcg/tcg-op-ldst.c
+++ b/tcg/tcg-op-ldst.c
@@ -148,11 +148,11 @@ static TCGv_i64 plugin_maybe_preserve_addr(TCGTemp *addr)
return NULL;
}
+#ifdef CONFIG_PLUGIN
static void
plugin_gen_mem_callbacks(TCGv_i64 copy_addr, TCGTemp *orig_addr, MemOpIdx oi,
enum qemu_plugin_mem_rw rw)
{
-#ifdef CONFIG_PLUGIN
if (tcg_ctx->plugin_insn != NULL) {
qemu_plugin_meminfo_t info = make_plugin_meminfo(oi, rw);
@@ -172,6 +172,54 @@ plugin_gen_mem_callbacks(TCGv_i64 copy_addr, TCGTemp *orig_addr, MemOpIdx oi,
}
}
}
+}
+#endif
+
+static void
+plugin_gen_mem_callbacks_i32(TCGv_i32 val,
+ TCGv_i64 copy_addr, TCGTemp *orig_addr,
+ MemOpIdx oi, enum qemu_plugin_mem_rw rw)
+{
+#ifdef CONFIG_PLUGIN
+ if (tcg_ctx->plugin_insn != NULL) {
+ tcg_gen_st_i32(val, tcg_env,
+ offsetof(CPUState, neg.plugin_mem_value_low) -
+ sizeof(CPUState) + (HOST_BIG_ENDIAN * 4));
+ plugin_gen_mem_callbacks(copy_addr, orig_addr, oi, rw);
+ }
+#endif
+}
+
+static void
+plugin_gen_mem_callbacks_i64(TCGv_i64 val,
+ TCGv_i64 copy_addr, TCGTemp *orig_addr,
+ MemOpIdx oi, enum qemu_plugin_mem_rw rw)
+{
+#ifdef CONFIG_PLUGIN
+ if (tcg_ctx->plugin_insn != NULL) {
+ tcg_gen_st_i64(val, tcg_env,
+ offsetof(CPUState, neg.plugin_mem_value_low) -
+ sizeof(CPUState));
+ plugin_gen_mem_callbacks(copy_addr, orig_addr, oi, rw);
+ }
+#endif
+}
+
+static void
+plugin_gen_mem_callbacks_i128(TCGv_i128 val,
+ TCGv_i64 copy_addr, TCGTemp *orig_addr,
+ MemOpIdx oi, enum qemu_plugin_mem_rw rw)
+{
+#ifdef CONFIG_PLUGIN
+ if (tcg_ctx->plugin_insn != NULL) {
+ tcg_gen_st_i64(TCGV128_LOW(val), tcg_env,
+ offsetof(CPUState, neg.plugin_mem_value_low) -
+ sizeof(CPUState));
+ tcg_gen_st_i64(TCGV128_HIGH(val), tcg_env,
+ offsetof(CPUState, neg.plugin_mem_value_high) -
+ sizeof(CPUState));
+ plugin_gen_mem_callbacks(copy_addr, orig_addr, oi, rw);
+ }
#endif
}
@@ -203,7 +251,8 @@ static void tcg_gen_qemu_ld_i32_int(TCGv_i32 val, TCGTemp *addr,
opc = INDEX_op_qemu_ld_a64_i32;
}
gen_ldst(opc, tcgv_i32_temp(val), NULL, addr, oi);
- plugin_gen_mem_callbacks(copy_addr, addr, orig_oi, QEMU_PLUGIN_MEM_R);
+ plugin_gen_mem_callbacks_i32(val, copy_addr, addr, orig_oi,
+ QEMU_PLUGIN_MEM_R);
if ((orig_memop ^ memop) & MO_BSWAP) {
switch (orig_memop & MO_SIZE) {
@@ -271,7 +320,7 @@ static void tcg_gen_qemu_st_i32_int(TCGv_i32 val, TCGTemp *addr,
}
}
gen_ldst(opc, tcgv_i32_temp(val), NULL, addr, oi);
- plugin_gen_mem_callbacks(NULL, addr, orig_oi, QEMU_PLUGIN_MEM_W);
+ plugin_gen_mem_callbacks_i32(val, NULL, addr, orig_oi, QEMU_PLUGIN_MEM_W);
if (swap) {
tcg_temp_free_i32(swap);
@@ -324,7 +373,8 @@ static void tcg_gen_qemu_ld_i64_int(TCGv_i64 val, TCGTemp *addr,
opc = INDEX_op_qemu_ld_a64_i64;
}
gen_ldst_i64(opc, val, addr, oi);
- plugin_gen_mem_callbacks(copy_addr, addr, orig_oi, QEMU_PLUGIN_MEM_R);
+ plugin_gen_mem_callbacks_i64(val, copy_addr, addr, orig_oi,
+ QEMU_PLUGIN_MEM_R);
if ((orig_memop ^ memop) & MO_BSWAP) {
int flags = (orig_memop & MO_SIGN
@@ -396,7 +446,7 @@ static void tcg_gen_qemu_st_i64_int(TCGv_i64 val, TCGTemp *addr,
opc = INDEX_op_qemu_st_a64_i64;
}
gen_ldst_i64(opc, val, addr, oi);
- plugin_gen_mem_callbacks(NULL, addr, orig_oi, QEMU_PLUGIN_MEM_W);
+ plugin_gen_mem_callbacks_i64(val, NULL, addr, orig_oi, QEMU_PLUGIN_MEM_W);
if (swap) {
tcg_temp_free_i64(swap);
@@ -606,7 +656,8 @@ static void tcg_gen_qemu_ld_i128_int(TCGv_i128 val, TCGTemp *addr,
tcg_constant_i32(orig_oi));
}
- plugin_gen_mem_callbacks(ext_addr, addr, orig_oi, QEMU_PLUGIN_MEM_R);
+ plugin_gen_mem_callbacks_i128(val, ext_addr, addr, orig_oi,
+ QEMU_PLUGIN_MEM_R);
}
void tcg_gen_qemu_ld_i128_chk(TCGv_i128 val, TCGTemp *addr, TCGArg idx,
@@ -722,7 +773,8 @@ static void tcg_gen_qemu_st_i128_int(TCGv_i128 val, TCGTemp *addr,
tcg_constant_i32(orig_oi));
}
- plugin_gen_mem_callbacks(ext_addr, addr, orig_oi, QEMU_PLUGIN_MEM_W);
+ plugin_gen_mem_callbacks_i128(val, ext_addr, addr, orig_oi,
+ QEMU_PLUGIN_MEM_W);
}
void tcg_gen_qemu_st_i128_chk(TCGv_i128 val, TCGTemp *addr, TCGArg idx,
diff --git a/accel/tcg/atomic_common.c.inc b/accel/tcg/atomic_common.c.inc
index 95a5c5ff12..6056598c23 100644
--- a/accel/tcg/atomic_common.c.inc
+++ b/accel/tcg/atomic_common.c.inc
@@ -14,9 +14,20 @@
*/
static void atomic_trace_rmw_post(CPUArchState *env, uint64_t addr,
+ uint64_t read_value_low,
+ uint64_t read_value_high,
+ uint64_t write_value_low,
+ uint64_t write_value_high,
MemOpIdx oi)
{
- qemu_plugin_vcpu_mem_cb(env_cpu(env), addr, oi, QEMU_PLUGIN_MEM_RW);
+ if (cpu_plugin_mem_cbs_enabled(env_cpu(env))) {
+ qemu_plugin_vcpu_mem_cb(env_cpu(env), addr,
+ read_value_low, read_value_high,
+ oi, QEMU_PLUGIN_MEM_R);
+ qemu_plugin_vcpu_mem_cb(env_cpu(env), addr,
+ write_value_low, write_value_high,
+ oi, QEMU_PLUGIN_MEM_W);
+ }
}
/*
diff --git a/accel/tcg/ldst_common.c.inc b/accel/tcg/ldst_common.c.inc
index 87ceb95487..ebbf380d76 100644
--- a/accel/tcg/ldst_common.c.inc
+++ b/accel/tcg/ldst_common.c.inc
@@ -123,10 +123,15 @@ void helper_st_i128(CPUArchState *env, uint64_t addr, Int128 val, MemOpIdx oi)
* Load helpers for cpu_ldst.h
*/
-static void plugin_load_cb(CPUArchState *env, abi_ptr addr, MemOpIdx oi)
+static void plugin_load_cb(CPUArchState *env, abi_ptr addr,
+ uint64_t value_low,
+ uint64_t value_high,
+ MemOpIdx oi)
{
if (cpu_plugin_mem_cbs_enabled(env_cpu(env))) {
- qemu_plugin_vcpu_mem_cb(env_cpu(env), addr, oi, QEMU_PLUGIN_MEM_R);
+ qemu_plugin_vcpu_mem_cb(env_cpu(env), addr,
+ value_low, value_high,
+ oi, QEMU_PLUGIN_MEM_R);
}
}
@@ -136,7 +141,7 @@ uint8_t cpu_ldb_mmu(CPUArchState *env, abi_ptr addr, MemOpIdx oi, uintptr_t ra)
tcg_debug_assert((get_memop(oi) & MO_SIZE) == MO_UB);
ret = do_ld1_mmu(env_cpu(env), addr, oi, ra, MMU_DATA_LOAD);
- plugin_load_cb(env, addr, oi);
+ plugin_load_cb(env, addr, ret, 0, oi);
return ret;
}
@@ -147,7 +152,7 @@ uint16_t cpu_ldw_mmu(CPUArchState *env, abi_ptr addr,
tcg_debug_assert((get_memop(oi) & MO_SIZE) == MO_16);
ret = do_ld2_mmu(env_cpu(env), addr, oi, ra, MMU_DATA_LOAD);
- plugin_load_cb(env, addr, oi);
+ plugin_load_cb(env, addr, ret, 0, oi);
return ret;
}
@@ -158,7 +163,7 @@ uint32_t cpu_ldl_mmu(CPUArchState *env, abi_ptr addr,
tcg_debug_assert((get_memop(oi) & MO_SIZE) == MO_32);
ret = do_ld4_mmu(env_cpu(env), addr, oi, ra, MMU_DATA_LOAD);
- plugin_load_cb(env, addr, oi);
+ plugin_load_cb(env, addr, ret, 0, oi);
return ret;
}
@@ -169,7 +174,7 @@ uint64_t cpu_ldq_mmu(CPUArchState *env, abi_ptr addr,
tcg_debug_assert((get_memop(oi) & MO_SIZE) == MO_64);
ret = do_ld8_mmu(env_cpu(env), addr, oi, ra, MMU_DATA_LOAD);
- plugin_load_cb(env, addr, oi);
+ plugin_load_cb(env, addr, ret, 0, oi);
return ret;
}
@@ -180,7 +185,7 @@ Int128 cpu_ld16_mmu(CPUArchState *env, abi_ptr addr,
tcg_debug_assert((get_memop(oi) & MO_SIZE) == MO_128);
ret = do_ld16_mmu(env_cpu(env), addr, oi, ra);
- plugin_load_cb(env, addr, oi);
+ plugin_load_cb(env, addr, int128_getlo(ret), int128_gethi(ret), oi);
return ret;
}
@@ -188,10 +193,15 @@ Int128 cpu_ld16_mmu(CPUArchState *env, abi_ptr addr,
* Store helpers for cpu_ldst.h
*/
-static void plugin_store_cb(CPUArchState *env, abi_ptr addr, MemOpIdx oi)
+static void plugin_store_cb(CPUArchState *env, abi_ptr addr,
+ uint64_t value_low,
+ uint64_t value_high,
+ MemOpIdx oi)
{
if (cpu_plugin_mem_cbs_enabled(env_cpu(env))) {
- qemu_plugin_vcpu_mem_cb(env_cpu(env), addr, oi, QEMU_PLUGIN_MEM_W);
+ qemu_plugin_vcpu_mem_cb(env_cpu(env), addr,
+ value_low, value_high,
+ oi, QEMU_PLUGIN_MEM_W);
}
}
@@ -199,7 +209,7 @@ void cpu_stb_mmu(CPUArchState *env, abi_ptr addr, uint8_t val,
MemOpIdx oi, uintptr_t retaddr)
{
helper_stb_mmu(env, addr, val, oi, retaddr);
- plugin_store_cb(env, addr, oi);
+ plugin_store_cb(env, addr, val, 0, oi);
}
void cpu_stw_mmu(CPUArchState *env, abi_ptr addr, uint16_t val,
@@ -207,7 +217,7 @@ void cpu_stw_mmu(CPUArchState *env, abi_ptr addr, uint16_t val,
{
tcg_debug_assert((get_memop(oi) & MO_SIZE) == MO_16);
do_st2_mmu(env_cpu(env), addr, val, oi, retaddr);
- plugin_store_cb(env, addr, oi);
+ plugin_store_cb(env, addr, val, 0, oi);
}
void cpu_stl_mmu(CPUArchState *env, abi_ptr addr, uint32_t val,
@@ -215,7 +225,7 @@ void cpu_stl_mmu(CPUArchState *env, abi_ptr addr, uint32_t val,
{
tcg_debug_assert((get_memop(oi) & MO_SIZE) == MO_32);
do_st4_mmu(env_cpu(env), addr, val, oi, retaddr);
- plugin_store_cb(env, addr, oi);
+ plugin_store_cb(env, addr, val, 0, oi);
}
void cpu_stq_mmu(CPUArchState *env, abi_ptr addr, uint64_t val,
@@ -223,7 +233,7 @@ void cpu_stq_mmu(CPUArchState *env, abi_ptr addr, uint64_t val,
{
tcg_debug_assert((get_memop(oi) & MO_SIZE) == MO_64);
do_st8_mmu(env_cpu(env), addr, val, oi, retaddr);
- plugin_store_cb(env, addr, oi);
+ plugin_store_cb(env, addr, val, 0, oi);
}
void cpu_st16_mmu(CPUArchState *env, abi_ptr addr, Int128 val,
@@ -231,7 +241,7 @@ void cpu_st16_mmu(CPUArchState *env, abi_ptr addr, Int128 val,
{
tcg_debug_assert((get_memop(oi) & MO_SIZE) == MO_128);
do_st16_mmu(env_cpu(env), addr, val, oi, retaddr);
- plugin_store_cb(env, addr, oi);
+ plugin_store_cb(env, addr, int128_getlo(val), int128_gethi(val), oi);
}
/*
--
2.39.5
^ permalink raw reply related [flat|nested] 23+ messages in thread* [PULL 05/18] plugins: extend API to get latest memory value accessed
2024-09-18 21:06 [PULL 00/18] tcg plugins (deprecations, mem apis, contrib plugins) Alex Bennée
` (3 preceding siblings ...)
2024-09-18 21:06 ` [PULL 04/18] plugins: save value during memory accesses Alex Bennée
@ 2024-09-18 21:06 ` Alex Bennée
2024-09-18 21:07 ` [PULL 06/18] tests/tcg: add mechanism to run specific tests with plugins Alex Bennée
` (13 subsequent siblings)
18 siblings, 0 replies; 23+ messages in thread
From: Alex Bennée @ 2024-09-18 21:06 UTC (permalink / raw)
To: qemu-devel
Cc: Pierrick Bouvier, Richard Henderson, Xingtao Yao,
Alex Bennée, Alexandre Iooss, Mahmoud Mandour
From: Pierrick Bouvier <pierrick.bouvier@linaro.org>
This value can be accessed only during a memory callback, using
new qemu_plugin_mem_get_value function.
Returned value can be extended when QEMU will support accesses wider
than 128 bits.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1719
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2152
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Xingtao Yao <yaoxt.fnst@fujitsu.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Message-Id: <20240724194708.1843704-3-pierrick.bouvier@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240916085400.1046925-6-alex.bennee@linaro.org>
diff --git a/include/qemu/qemu-plugin.h b/include/qemu/qemu-plugin.h
index c71c705b69..649ce89815 100644
--- a/include/qemu/qemu-plugin.h
+++ b/include/qemu/qemu-plugin.h
@@ -262,6 +262,29 @@ enum qemu_plugin_mem_rw {
QEMU_PLUGIN_MEM_RW,
};
+enum qemu_plugin_mem_value_type {
+ QEMU_PLUGIN_MEM_VALUE_U8,
+ QEMU_PLUGIN_MEM_VALUE_U16,
+ QEMU_PLUGIN_MEM_VALUE_U32,
+ QEMU_PLUGIN_MEM_VALUE_U64,
+ QEMU_PLUGIN_MEM_VALUE_U128,
+};
+
+/* typedef qemu_plugin_mem_value - value accessed during a load/store */
+typedef struct {
+ enum qemu_plugin_mem_value_type type;
+ union {
+ uint8_t u8;
+ uint16_t u16;
+ uint32_t u32;
+ uint64_t u64;
+ struct {
+ uint64_t low;
+ uint64_t high;
+ } u128;
+ } data;
+} qemu_plugin_mem_value;
+
/**
* enum qemu_plugin_cond - condition to enable callback
*
@@ -551,6 +574,15 @@ bool qemu_plugin_mem_is_big_endian(qemu_plugin_meminfo_t info);
QEMU_PLUGIN_API
bool qemu_plugin_mem_is_store(qemu_plugin_meminfo_t info);
+/**
+ * qemu_plugin_mem_get_mem_value() - return last value loaded/stored
+ * @info: opaque memory transaction handle
+ *
+ * Returns: memory value
+ */
+QEMU_PLUGIN_API
+qemu_plugin_mem_value qemu_plugin_mem_get_value(qemu_plugin_meminfo_t info);
+
/**
* qemu_plugin_get_hwaddr() - return handle for memory operation
* @info: opaque memory info structure
diff --git a/plugins/api.c b/plugins/api.c
index 2ff13d09de..3316d4a04d 100644
--- a/plugins/api.c
+++ b/plugins/api.c
@@ -351,6 +351,39 @@ bool qemu_plugin_mem_is_store(qemu_plugin_meminfo_t info)
return get_plugin_meminfo_rw(info) & QEMU_PLUGIN_MEM_W;
}
+qemu_plugin_mem_value qemu_plugin_mem_get_value(qemu_plugin_meminfo_t info)
+{
+ uint64_t low = current_cpu->neg.plugin_mem_value_low;
+ qemu_plugin_mem_value value;
+
+ switch (qemu_plugin_mem_size_shift(info)) {
+ case 0:
+ value.type = QEMU_PLUGIN_MEM_VALUE_U8;
+ value.data.u8 = (uint8_t)low;
+ break;
+ case 1:
+ value.type = QEMU_PLUGIN_MEM_VALUE_U16;
+ value.data.u16 = (uint16_t)low;
+ break;
+ case 2:
+ value.type = QEMU_PLUGIN_MEM_VALUE_U32;
+ value.data.u32 = (uint32_t)low;
+ break;
+ case 3:
+ value.type = QEMU_PLUGIN_MEM_VALUE_U64;
+ value.data.u64 = low;
+ break;
+ case 4:
+ value.type = QEMU_PLUGIN_MEM_VALUE_U128;
+ value.data.u128.low = low;
+ value.data.u128.high = current_cpu->neg.plugin_mem_value_high;
+ break;
+ default:
+ g_assert_not_reached();
+ }
+ return value;
+}
+
/*
* Virtual Memory queries
*/
diff --git a/plugins/qemu-plugins.symbols b/plugins/qemu-plugins.symbols
index ca773d8d9f..eed9d8abd9 100644
--- a/plugins/qemu-plugins.symbols
+++ b/plugins/qemu-plugins.symbols
@@ -13,6 +13,7 @@
qemu_plugin_insn_size;
qemu_plugin_insn_symbol;
qemu_plugin_insn_vaddr;
+ qemu_plugin_mem_get_value;
qemu_plugin_mem_is_big_endian;
qemu_plugin_mem_is_sign_extended;
qemu_plugin_mem_is_store;
--
2.39.5
^ permalink raw reply related [flat|nested] 23+ messages in thread* [PULL 06/18] tests/tcg: add mechanism to run specific tests with plugins
2024-09-18 21:06 [PULL 00/18] tcg plugins (deprecations, mem apis, contrib plugins) Alex Bennée
` (4 preceding siblings ...)
2024-09-18 21:06 ` [PULL 05/18] plugins: extend API to get latest memory value accessed Alex Bennée
@ 2024-09-18 21:07 ` Alex Bennée
2024-09-18 21:07 ` [PULL 07/18] tests/tcg: allow to check output of plugins Alex Bennée
` (12 subsequent siblings)
18 siblings, 0 replies; 23+ messages in thread
From: Alex Bennée @ 2024-09-18 21:07 UTC (permalink / raw)
To: qemu-devel
Cc: Pierrick Bouvier, Xingtao Yao, Richard Henderson,
Alex Bennée, Philippe Mathieu-Daudé
From: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Only multiarch tests are run with plugins, and we want to be able to run
per-arch test with plugins too.
Tested-by: Xingtao Yao <yaoxt.fnst@fujitsu.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Message-Id: <20240724194708.1843704-4-pierrick.bouvier@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240916085400.1046925-7-alex.bennee@linaro.org>
diff --git a/tests/tcg/Makefile.target b/tests/tcg/Makefile.target
index 452a2cde65..c5b1c7a786 100644
--- a/tests/tcg/Makefile.target
+++ b/tests/tcg/Makefile.target
@@ -152,10 +152,11 @@ PLUGINS=$(patsubst %.c, lib%.so, $(notdir $(wildcard $(PLUGIN_SRC)/*.c)))
# only expand MULTIARCH_TESTS which are common on most of our targets
# to avoid an exponential explosion as new tests are added. We also
# add some special helpers the run-plugin- rules can use below.
+# In more, extra tests can be added using ADDITIONAL_PLUGINS_TESTS variable.
ifneq ($(MULTIARCH_TESTS),)
$(foreach p,$(PLUGINS), \
- $(foreach t,$(MULTIARCH_TESTS),\
+ $(foreach t,$(MULTIARCH_TESTS) $(ADDITIONAL_PLUGINS_TESTS),\
$(eval run-plugin-$(t)-with-$(p): $t $p) \
$(eval RUN_TESTS+=run-plugin-$(t)-with-$(p))))
endif # MULTIARCH_TESTS
--
2.39.5
^ permalink raw reply related [flat|nested] 23+ messages in thread* [PULL 07/18] tests/tcg: allow to check output of plugins
2024-09-18 21:06 [PULL 00/18] tcg plugins (deprecations, mem apis, contrib plugins) Alex Bennée
` (5 preceding siblings ...)
2024-09-18 21:07 ` [PULL 06/18] tests/tcg: add mechanism to run specific tests with plugins Alex Bennée
@ 2024-09-18 21:07 ` Alex Bennée
2024-09-18 21:07 ` [PULL 08/18] tests/tcg/plugins/mem: add option to print memory accesses Alex Bennée
` (11 subsequent siblings)
18 siblings, 0 replies; 23+ messages in thread
From: Alex Bennée @ 2024-09-18 21:07 UTC (permalink / raw)
To: qemu-devel
Cc: Pierrick Bouvier, Xingtao Yao, Richard Henderson,
Alex Bennée, Philippe Mathieu-Daudé
From: Pierrick Bouvier <pierrick.bouvier@linaro.org>
A specific plugin test can now read and check a plugin output, to ensure
it contains expected values.
Tested-by: Xingtao Yao <yaoxt.fnst@fujitsu.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Message-Id: <20240724194708.1843704-5-pierrick.bouvier@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240916085400.1046925-8-alex.bennee@linaro.org>
diff --git a/tests/tcg/Makefile.target b/tests/tcg/Makefile.target
index c5b1c7a786..2da70b2fcf 100644
--- a/tests/tcg/Makefile.target
+++ b/tests/tcg/Makefile.target
@@ -90,6 +90,7 @@ CFLAGS=
LDFLAGS=
QEMU_OPTS=
+CHECK_PLUGIN_OUTPUT_COMMAND=
# If TCG debugging, or TCI is enabled things are a lot slower
@@ -180,6 +181,10 @@ run-plugin-%:
-plugin $(PLUGIN_LIB)/$(call extract-plugin,$@)$(PLUGIN_ARGS) \
-d plugin -D $*.pout \
$(call strip-plugin,$<))
+ $(if $(CHECK_PLUGIN_OUTPUT_COMMAND), \
+ $(call quiet-command, $(CHECK_PLUGIN_OUTPUT_COMMAND) $*.pout, \
+ TEST, check plugin $(call extract-plugin,$@) output \
+ with $(call strip-plugin,$<)))
else
run-%: %
$(call run-test, $<, \
@@ -194,6 +199,10 @@ run-plugin-%:
-plugin $(PLUGIN_LIB)/$(call extract-plugin,$@)$(PLUGIN_ARGS) \
-d plugin -D $*.pout \
$(QEMU_OPTS) $(call strip-plugin,$<))
+ $(if $(CHECK_PLUGIN_OUTPUT_COMMAND), \
+ $(call quiet-command, $(CHECK_PLUGIN_OUTPUT_COMMAND) $*.pout, \
+ TEST, check plugin $(call extract-plugin,$@) output \
+ with $(call strip-plugin,$<)))
endif
gdb-%: %
--
2.39.5
^ permalink raw reply related [flat|nested] 23+ messages in thread* [PULL 08/18] tests/tcg/plugins/mem: add option to print memory accesses
2024-09-18 21:06 [PULL 00/18] tcg plugins (deprecations, mem apis, contrib plugins) Alex Bennée
` (6 preceding siblings ...)
2024-09-18 21:07 ` [PULL 07/18] tests/tcg: allow to check output of plugins Alex Bennée
@ 2024-09-18 21:07 ` Alex Bennée
2024-09-18 21:07 ` [PULL 09/18] tests/tcg/multiarch: add test for plugin memory access Alex Bennée
` (10 subsequent siblings)
18 siblings, 0 replies; 23+ messages in thread
From: Alex Bennée @ 2024-09-18 21:07 UTC (permalink / raw)
To: qemu-devel
Cc: Pierrick Bouvier, Richard Henderson, Xingtao Yao,
Alex Bennée, Alexandre Iooss, Mahmoud Mandour
From: Pierrick Bouvier <pierrick.bouvier@linaro.org>
By using "print-accesses=true" option, mem plugin will now print every
value accessed, with associated size, type (store vs load), symbol,
instruction address and phys/virt address accessed.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Xingtao Yao <yaoxt.fnst@fujitsu.com>
Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Message-Id: <20240724194708.1843704-6-pierrick.bouvier@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240916085400.1046925-9-alex.bennee@linaro.org>
diff --git a/tests/tcg/plugins/mem.c b/tests/tcg/plugins/mem.c
index b650dddcce..086e6f5bdf 100644
--- a/tests/tcg/plugins/mem.c
+++ b/tests/tcg/plugins/mem.c
@@ -21,10 +21,15 @@ typedef struct {
uint64_t io_count;
} CPUCount;
+typedef struct {
+ uint64_t vaddr;
+ const char *sym;
+} InsnInfo;
+
static struct qemu_plugin_scoreboard *counts;
static qemu_plugin_u64 mem_count;
static qemu_plugin_u64 io_count;
-static bool do_inline, do_callback;
+static bool do_inline, do_callback, do_print_accesses;
static bool do_haddr;
static enum qemu_plugin_mem_rw rw = QEMU_PLUGIN_MEM_RW;
@@ -60,6 +65,44 @@ static void vcpu_mem(unsigned int cpu_index, qemu_plugin_meminfo_t meminfo,
}
}
+static void print_access(unsigned int cpu_index, qemu_plugin_meminfo_t meminfo,
+ uint64_t vaddr, void *udata)
+{
+ InsnInfo *insn_info = udata;
+ unsigned size = 8 << qemu_plugin_mem_size_shift(meminfo);
+ const char *type = qemu_plugin_mem_is_store(meminfo) ? "store" : "load";
+ qemu_plugin_mem_value value = qemu_plugin_mem_get_value(meminfo);
+ uint64_t hwaddr =
+ qemu_plugin_hwaddr_phys_addr(qemu_plugin_get_hwaddr(meminfo, vaddr));
+ g_autoptr(GString) out = g_string_new("");
+ g_string_printf(out,
+ "0x%"PRIx64",%s,0x%"PRIx64",0x%"PRIx64",%d,%s,",
+ insn_info->vaddr, insn_info->sym,
+ vaddr, hwaddr, size, type);
+ switch (value.type) {
+ case QEMU_PLUGIN_MEM_VALUE_U8:
+ g_string_append_printf(out, "0x%02"PRIx8, value.data.u8);
+ break;
+ case QEMU_PLUGIN_MEM_VALUE_U16:
+ g_string_append_printf(out, "0x%04"PRIx16, value.data.u16);
+ break;
+ case QEMU_PLUGIN_MEM_VALUE_U32:
+ g_string_append_printf(out, "0x%08"PRIx32, value.data.u32);
+ break;
+ case QEMU_PLUGIN_MEM_VALUE_U64:
+ g_string_append_printf(out, "0x%016"PRIx64, value.data.u64);
+ break;
+ case QEMU_PLUGIN_MEM_VALUE_U128:
+ g_string_append_printf(out, "0x%016"PRIx64"%016"PRIx64,
+ value.data.u128.high, value.data.u128.low);
+ break;
+ default:
+ g_assert_not_reached();
+ }
+ g_string_append_printf(out, "\n");
+ qemu_plugin_outs(out->str);
+}
+
static void vcpu_tb_trans(qemu_plugin_id_t id, struct qemu_plugin_tb *tb)
{
size_t n = qemu_plugin_tb_n_insns(tb);
@@ -79,6 +122,16 @@ static void vcpu_tb_trans(qemu_plugin_id_t id, struct qemu_plugin_tb *tb)
QEMU_PLUGIN_CB_NO_REGS,
rw, NULL);
}
+ if (do_print_accesses) {
+ /* we leak this pointer, to avoid locking to keep track of it */
+ InsnInfo *insn_info = g_malloc(sizeof(InsnInfo));
+ const char *sym = qemu_plugin_insn_symbol(insn);
+ insn_info->sym = sym ? sym : "";
+ insn_info->vaddr = qemu_plugin_insn_vaddr(insn);
+ qemu_plugin_register_vcpu_mem_cb(insn, print_access,
+ QEMU_PLUGIN_CB_NO_REGS,
+ rw, (void *) insn_info);
+ }
}
}
@@ -117,6 +170,12 @@ QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plugin_id_t id,
fprintf(stderr, "boolean argument parsing failed: %s\n", opt);
return -1;
}
+ } else if (g_strcmp0(tokens[0], "print-accesses") == 0) {
+ if (!qemu_plugin_bool_parse(tokens[0], tokens[1],
+ &do_print_accesses)) {
+ fprintf(stderr, "boolean argument parsing failed: %s\n", opt);
+ return -1;
+ }
} else {
fprintf(stderr, "option parsing failed: %s\n", opt);
return -1;
@@ -129,6 +188,14 @@ QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plugin_id_t id,
return -1;
}
+ if (do_print_accesses) {
+ g_autoptr(GString) out = g_string_new("");
+ g_string_printf(out,
+ "insn_vaddr,insn_symbol,mem_vaddr,mem_hwaddr,"
+ "access_size,access_type,mem_value\n");
+ qemu_plugin_outs(out->str);
+ }
+
counts = qemu_plugin_scoreboard_new(sizeof(CPUCount));
mem_count = qemu_plugin_scoreboard_u64_in_struct(
counts, CPUCount, mem_count);
--
2.39.5
^ permalink raw reply related [flat|nested] 23+ messages in thread* [PULL 09/18] tests/tcg/multiarch: add test for plugin memory access
2024-09-18 21:06 [PULL 00/18] tcg plugins (deprecations, mem apis, contrib plugins) Alex Bennée
` (7 preceding siblings ...)
2024-09-18 21:07 ` [PULL 08/18] tests/tcg/plugins/mem: add option to print memory accesses Alex Bennée
@ 2024-09-18 21:07 ` Alex Bennée
2024-09-18 21:07 ` [PULL 10/18] tests/tcg: clean up output of memory system test Alex Bennée
` (9 subsequent siblings)
18 siblings, 0 replies; 23+ messages in thread
From: Alex Bennée @ 2024-09-18 21:07 UTC (permalink / raw)
To: qemu-devel
Cc: Pierrick Bouvier, Xingtao Yao, Alex Bennée,
Richard Henderson, Nicholas Piggin, Daniel Henrique Barboza,
open list:PowerPC TCG CPUs
From: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Add an explicit test to check expected memory values are read/written.
8,16,32 load/store are tested for all arch.
64,128 load/store are tested for aarch64/x64.
atomic operations (8,16,32,64) are tested for x64 only.
By default, atomic accesses are non atomic if a single cpu is running,
so we force creation of a second one by creating a new thread first.
load/store helpers code path can't be triggered easily in user mode (no
softmmu), so we can't test it here.
Output of test-plugin-mem-access.c is the list of expected patterns in
plugin output. By reading stdout, we can compare to plugins output and
have a multiarch test.
Can be run with:
make -C build/tests/tcg/$ARCH-linux-user run-plugin-test-plugin-mem-access-with-libmem.so
Tested-by: Xingtao Yao <yaoxt.fnst@fujitsu.com>
Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240910172033.1427812-7-pierrick.bouvier@linaro.org>
Message-Id: <20240916085400.1046925-10-alex.bennee@linaro.org>
diff --git a/tests/tcg/multiarch/test-plugin-mem-access.c b/tests/tcg/multiarch/test-plugin-mem-access.c
new file mode 100644
index 0000000000..057b9aac9f
--- /dev/null
+++ b/tests/tcg/multiarch/test-plugin-mem-access.c
@@ -0,0 +1,177 @@
+/*
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ *
+ * Check if we detect all memory accesses expected using plugin API.
+ * Used in conjunction with ./check-plugin-mem-access.sh check script.
+ * Output of this program is the list of patterns expected in plugin output.
+ *
+ * 8,16,32 load/store are tested for all arch.
+ * 64,128 load/store are tested for aarch64/x64.
+ * atomic operations (8,16,32,64) are tested for x64 only.
+ */
+
+#include <pthread.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#if defined(__x86_64__)
+#include <emmintrin.h>
+#elif defined(__aarch64__)
+#include <arm_neon.h>
+#endif /* __x86_64__ */
+
+static void *data;
+
+/* ,store_u8,.*,8,store,0xf1 */
+#define PRINT_EXPECTED(function, type, value, action) \
+do { \
+ printf(",%s,.*,%d,%s,%s\n", \
+ #function, (int) sizeof(type) * 8, action, value); \
+} \
+while (0)
+
+#define DEFINE_STORE(name, type, value) \
+ \
+static void print_expected_store_##name(void) \
+{ \
+ PRINT_EXPECTED(store_##name, type, #value, "store"); \
+} \
+ \
+static void store_##name(void) \
+{ \
+ *((type *)data) = value; \
+ print_expected_store_##name(); \
+}
+
+#define DEFINE_ATOMIC_OP(name, type, value) \
+ \
+static void print_expected_atomic_op_##name(void) \
+{ \
+ PRINT_EXPECTED(atomic_op_##name, type, "0x0*42", "load"); \
+ PRINT_EXPECTED(atomic_op_##name, type, #value, "store"); \
+} \
+ \
+static void atomic_op_##name(void) \
+{ \
+ *((type *)data) = 0x42; \
+ __sync_val_compare_and_swap((type *)data, 0x42, value); \
+ print_expected_atomic_op_##name(); \
+}
+
+#define DEFINE_LOAD(name, type, value) \
+ \
+static void print_expected_load_##name(void) \
+{ \
+ PRINT_EXPECTED(load_##name, type, #value, "load"); \
+} \
+ \
+static void load_##name(void) \
+{ \
+ \
+ /* volatile forces load to be generated. */ \
+ volatile type src = *((type *) data); \
+ volatile type dest = src; \
+ (void)src, (void)dest; \
+ print_expected_load_##name(); \
+}
+
+DEFINE_STORE(u8, uint8_t, 0xf1)
+DEFINE_LOAD(u8, uint8_t, 0xf1)
+DEFINE_STORE(u16, uint16_t, 0xf123)
+DEFINE_LOAD(u16, uint16_t, 0xf123)
+DEFINE_STORE(u32, uint32_t, 0xff112233)
+DEFINE_LOAD(u32, uint32_t, 0xff112233)
+
+#if defined(__x86_64__) || defined(__aarch64__)
+DEFINE_STORE(u64, uint64_t, 0xf123456789abcdef)
+DEFINE_LOAD(u64, uint64_t, 0xf123456789abcdef)
+
+static void print_expected_store_u128(void)
+{
+ PRINT_EXPECTED(store_u128, __int128,
+ "0xf122334455667788f123456789abcdef", "store");
+}
+
+static void store_u128(void)
+{
+#ifdef __x86_64__
+ _mm_store_si128(data, _mm_set_epi32(0xf1223344, 0x55667788,
+ 0xf1234567, 0x89abcdef));
+#else
+ const uint32_t init[4] = {0x89abcdef, 0xf1234567, 0x55667788, 0xf1223344};
+ uint32x4_t vec = vld1q_u32(init);
+ vst1q_u32(data, vec);
+#endif /* __x86_64__ */
+ print_expected_store_u128();
+}
+
+static void print_expected_load_u128(void)
+{
+ PRINT_EXPECTED(load_u128, __int128,
+ "0xf122334455667788f123456789abcdef", "load");
+}
+
+static void load_u128(void)
+{
+#ifdef __x86_64__
+ __m128i var = _mm_load_si128(data);
+#else
+ uint32x4_t var = vld1q_u32(data);
+#endif
+ (void) var;
+ print_expected_load_u128();
+}
+#endif /* __x86_64__ || __aarch64__ */
+
+#if defined(__x86_64__)
+DEFINE_ATOMIC_OP(u8, uint8_t, 0xf1)
+DEFINE_ATOMIC_OP(u16, uint16_t, 0xf123)
+DEFINE_ATOMIC_OP(u32, uint32_t, 0xff112233)
+DEFINE_ATOMIC_OP(u64, uint64_t, 0xf123456789abcdef)
+#endif /* __x86_64__ */
+
+static void *f(void *p)
+{
+ return NULL;
+}
+
+int main(void)
+{
+ /*
+ * We force creation of a second thread to enable cpu flag CF_PARALLEL.
+ * This will generate atomic operations when needed.
+ */
+ pthread_t thread;
+ pthread_create(&thread, NULL, &f, NULL);
+ pthread_join(thread, NULL);
+
+ /* allocate storage up to 128 bits */
+ data = malloc(16);
+
+ store_u8();
+ load_u8();
+
+ store_u16();
+ load_u16();
+
+ store_u32();
+ load_u32();
+
+#if defined(__x86_64__) || defined(__aarch64__)
+ store_u64();
+ load_u64();
+
+ store_u128();
+ load_u128();
+#endif /* __x86_64__ || __aarch64__ */
+
+#if defined(__x86_64__)
+ atomic_op_u8();
+ atomic_op_u16();
+ atomic_op_u32();
+ atomic_op_u64();
+#endif /* __x86_64__ */
+
+ free(data);
+}
diff --git a/tests/tcg/alpha/Makefile.target b/tests/tcg/alpha/Makefile.target
index fdd7ddf64e..36d8ed1eae 100644
--- a/tests/tcg/alpha/Makefile.target
+++ b/tests/tcg/alpha/Makefile.target
@@ -12,4 +12,7 @@ test-cmov: EXTRA_CFLAGS=-DTEST_CMOV
test-cmov: test-cond.c
$(CC) $(CFLAGS) $(EXTRA_CFLAGS) $< -o $@ $(LDFLAGS)
+# Force generation of byte read/write
+test-plugin-mem-access: CFLAGS+=-mbwx
+
run-test-cmov: test-cmov
diff --git a/tests/tcg/multiarch/Makefile.target b/tests/tcg/multiarch/Makefile.target
index 5e3391ec9d..78b83d5575 100644
--- a/tests/tcg/multiarch/Makefile.target
+++ b/tests/tcg/multiarch/Makefile.target
@@ -170,5 +170,16 @@ run-plugin-semiconsole-with-%:
TESTS += semihosting semiconsole
endif
+# Test plugin memory access instrumentation
+run-plugin-test-plugin-mem-access-with-libmem.so: \
+ PLUGIN_ARGS=$(COMMA)print-accesses=true
+run-plugin-test-plugin-mem-access-with-libmem.so: \
+ CHECK_PLUGIN_OUTPUT_COMMAND= \
+ $(SRC_PATH)/tests/tcg/multiarch/check-plugin-output.sh \
+ $(QEMU) $<
+
+test-plugin-mem-access: CFLAGS+=-pthread -O0
+test-plugin-mem-access: LDFLAGS+=-pthread -O0
+
# Update TESTS
TESTS += $(MULTIARCH_TESTS)
diff --git a/tests/tcg/multiarch/check-plugin-output.sh b/tests/tcg/multiarch/check-plugin-output.sh
new file mode 100755
index 0000000000..80607f04b5
--- /dev/null
+++ b/tests/tcg/multiarch/check-plugin-output.sh
@@ -0,0 +1,36 @@
+#!/usr/bin/env bash
+
+# This script runs a given executable using qemu, and compare its standard
+# output with an expected plugin output.
+# Each line of output is searched (as a regexp) in the expected plugin output.
+
+set -euo pipefail
+
+die()
+{
+ echo "$@" 1>&2
+ exit 1
+}
+
+check()
+{
+ file=$1
+ pattern=$2
+ grep "$pattern" "$file" > /dev/null || die "\"$pattern\" not found in $file"
+}
+
+[ $# -eq 3 ] || die "usage: qemu_bin exe plugin_out_file"
+
+qemu_bin=$1; shift
+exe=$1;shift
+plugin_out=$1; shift
+
+expected()
+{
+ $qemu_bin $exe ||
+ die "running $exe failed"
+}
+
+expected | while read line; do
+ check "$plugin_out" "$line"
+done
diff --git a/tests/tcg/ppc64/Makefile.target b/tests/tcg/ppc64/Makefile.target
index 509a20be2b..1940886c73 100644
--- a/tests/tcg/ppc64/Makefile.target
+++ b/tests/tcg/ppc64/Makefile.target
@@ -55,4 +55,9 @@ PPC64_TESTS += signal_save_restore_xer
PPC64_TESTS += xxspltw
PPC64_TESTS += test-aes
+# ppc64 ABI uses function descriptors, and thus, QEMU can't find symbol for a
+# given instruction. Thus, we don't check output of mem-access plugin.
+run-plugin-test-plugin-mem-access-with-libmem.so: \
+ CHECK_PLUGIN_OUTPUT_COMMAND=
+
TESTS += $(PPC64_TESTS)
--
2.39.5
^ permalink raw reply related [flat|nested] 23+ messages in thread* [PULL 10/18] tests/tcg: clean up output of memory system test
2024-09-18 21:06 [PULL 00/18] tcg plugins (deprecations, mem apis, contrib plugins) Alex Bennée
` (8 preceding siblings ...)
2024-09-18 21:07 ` [PULL 09/18] tests/tcg/multiarch: add test for plugin memory access Alex Bennée
@ 2024-09-18 21:07 ` Alex Bennée
2024-09-18 21:07 ` [PULL 11/18] tests/tcg: only read/write 64 bit words on 64 bit systems Alex Bennée
` (8 subsequent siblings)
18 siblings, 0 replies; 23+ messages in thread
From: Alex Bennée @ 2024-09-18 21:07 UTC (permalink / raw)
To: qemu-devel; +Cc: Alex Bennée, Pierrick Bouvier
This is useful information when debugging memory issues so lets
improve by:
- include the ptr address for u8 fills (like the others)
- indicate the number of operations for reads and writes
- explicitly note when we are flushing
- move the fill printf to after the reset
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240916085400.1046925-11-alex.bennee@linaro.org>
diff --git a/tests/tcg/multiarch/system/memory.c b/tests/tcg/multiarch/system/memory.c
index 6eb2eb16f7..8f2371975d 100644
--- a/tests/tcg/multiarch/system/memory.c
+++ b/tests/tcg/multiarch/system/memory.c
@@ -63,12 +63,14 @@ static void init_test_data_u8(int unused_offset)
int i;
(void)(unused_offset);
- ml_printf("Filling test area with u8:");
+ ml_printf("Filling test area with u8 (%p):", ptr);
+
for (i = 0; i < TEST_SIZE; i++) {
*ptr++ = BYTE_NEXT(count);
pdot(i);
}
- ml_printf("done\n");
+
+ ml_printf("done %d @ %p\n", i, ptr);
}
/*
@@ -94,7 +96,7 @@ static void init_test_data_s8(bool neg_first)
*ptr++ = get_byte(i, !neg_first);
pdot(i);
}
- ml_printf("done\n");
+ ml_printf("done %d @ %p\n", i * 2, ptr);
}
/*
@@ -105,9 +107,18 @@ static void reset_start_data(int offset)
{
uint32_t *ptr = (uint32_t *) &test_data[0];
int i;
+
+ if (!offset) {
+ return;
+ }
+
+ ml_printf("Flushing %d bytes from %p: ", offset, ptr);
+
for (i = 0; i < offset; i++) {
*ptr++ = 0;
}
+
+ ml_printf("done %d @ %p\n", i, ptr);
}
static void init_test_data_u16(int offset)
@@ -117,17 +128,17 @@ static void init_test_data_u16(int offset)
const int max = (TEST_SIZE - offset) / sizeof(word);
int i;
- ml_printf("Filling test area with u16 (offset %d, %p):", offset, ptr);
-
reset_start_data(offset);
+ ml_printf("Filling test area with u16 (offset %d, %p):", offset, ptr);
+
for (i = 0; i < max; i++) {
uint16_t low = BYTE_NEXT(count), high = BYTE_NEXT(count);
word = BYTE_SHIFT(high, 1) | BYTE_SHIFT(low, 0);
*ptr++ = word;
pdot(i);
}
- ml_printf("done @ %p\n", ptr);
+ ml_printf("done %d @ %p\n", i, ptr);
}
static void init_test_data_u32(int offset)
@@ -137,10 +148,10 @@ static void init_test_data_u32(int offset)
const int max = (TEST_SIZE - offset) / sizeof(word);
int i;
- ml_printf("Filling test area with u32 (offset %d, %p):", offset, ptr);
-
reset_start_data(offset);
+ ml_printf("Filling test area with u32 (offset %d, %p):", offset, ptr);
+
for (i = 0; i < max; i++) {
uint32_t b4 = BYTE_NEXT(count), b3 = BYTE_NEXT(count);
uint32_t b2 = BYTE_NEXT(count), b1 = BYTE_NEXT(count);
@@ -149,7 +160,7 @@ static void init_test_data_u32(int offset)
*ptr++ = word;
pdot(i);
}
- ml_printf("done @ %p\n", ptr);
+ ml_printf("done %d @ %p\n", i, ptr);
}
static void init_test_data_u64(int offset)
@@ -159,10 +170,10 @@ static void init_test_data_u64(int offset)
const int max = (TEST_SIZE - offset) / sizeof(word);
int i;
- ml_printf("Filling test area with u64 (offset %d, %p):", offset, ptr);
-
reset_start_data(offset);
+ ml_printf("Filling test area with u64 (offset %d, %p):", offset, ptr);
+
for (i = 0; i < max; i++) {
uint64_t b8 = BYTE_NEXT(count), b7 = BYTE_NEXT(count);
uint64_t b6 = BYTE_NEXT(count), b5 = BYTE_NEXT(count);
@@ -174,7 +185,7 @@ static void init_test_data_u64(int offset)
*ptr++ = word;
pdot(i);
}
- ml_printf("done @ %p\n", ptr);
+ ml_printf("done %d @ %p\n", i, ptr);
}
static bool read_test_data_u16(int offset)
@@ -198,7 +209,7 @@ static bool read_test_data_u16(int offset)
}
}
- ml_printf("done @ %p\n", ptr);
+ ml_printf("done %d @ %p\n", i, ptr);
return true;
}
@@ -239,7 +250,7 @@ static bool read_test_data_u32(int offset)
pdot(i);
}
}
- ml_printf("done @ %p\n", ptr);
+ ml_printf("done %d @ %p\n", i, ptr);
return true;
}
@@ -293,7 +304,7 @@ static bool read_test_data_u64(int offset)
pdot(i);
}
}
- ml_printf("done @ %p\n", ptr);
+ ml_printf("done %d @ %p\n", i, ptr);
return true;
}
@@ -365,7 +376,7 @@ static bool read_test_data_s8(int offset, bool neg_first)
return false;
}
}
- ml_printf("done @ %p\n", ptr);
+ ml_printf("done %d @ %p\n", i * 2, ptr);
return true;
}
@@ -398,7 +409,7 @@ static bool read_test_data_s16(int offset, bool neg_first)
return false;
}
}
- ml_printf("done @ %p\n", ptr);
+ ml_printf("done %d @ %p\n", i, ptr);
return true;
}
@@ -431,7 +442,7 @@ static bool read_test_data_s32(int offset, bool neg_first)
return false;
}
}
- ml_printf("done @ %p\n", ptr);
+ ml_printf("done %d @ %p\n", i, ptr);
return true;
}
--
2.39.5
^ permalink raw reply related [flat|nested] 23+ messages in thread* [PULL 11/18] tests/tcg: only read/write 64 bit words on 64 bit systems
2024-09-18 21:06 [PULL 00/18] tcg plugins (deprecations, mem apis, contrib plugins) Alex Bennée
` (9 preceding siblings ...)
2024-09-18 21:07 ` [PULL 10/18] tests/tcg: clean up output of memory system test Alex Bennée
@ 2024-09-18 21:07 ` Alex Bennée
2024-09-18 21:07 ` [PULL 12/18] tests/tcg: ensure s390x-softmmu output redirected Alex Bennée
` (7 subsequent siblings)
18 siblings, 0 replies; 23+ messages in thread
From: Alex Bennée @ 2024-09-18 21:07 UTC (permalink / raw)
To: qemu-devel; +Cc: Alex Bennée, Pierrick Bouvier
While the compilers will generally happily synthesise a 64 bit value
for you on 32 bit systems it doesn't exercise anything on QEMU. It
also makes it hard to accurately compare the accesses to test_data
when instrumenting.
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240916085400.1046925-12-alex.bennee@linaro.org>
diff --git a/tests/tcg/multiarch/system/memory.c b/tests/tcg/multiarch/system/memory.c
index 8f2371975d..28080767b2 100644
--- a/tests/tcg/multiarch/system/memory.c
+++ b/tests/tcg/multiarch/system/memory.c
@@ -163,6 +163,7 @@ static void init_test_data_u32(int offset)
ml_printf("done %d @ %p\n", i, ptr);
}
+#if __SIZEOF_POINTER__ >= 8
static void init_test_data_u64(int offset)
{
uint8_t count = 0;
@@ -187,6 +188,7 @@ static void init_test_data_u64(int offset)
}
ml_printf("done %d @ %p\n", i, ptr);
}
+#endif
static bool read_test_data_u16(int offset)
{
@@ -254,6 +256,7 @@ static bool read_test_data_u32(int offset)
return true;
}
+#if __SIZEOF_POINTER__ >= 8
static bool read_test_data_u64(int offset)
{
uint64_t word, *ptr = (uint64_t *)&test_data[offset];
@@ -307,11 +310,16 @@ static bool read_test_data_u64(int offset)
ml_printf("done %d @ %p\n", i, ptr);
return true;
}
+#endif
/* Read the test data and verify at various offsets */
-read_ufn read_ufns[] = { read_test_data_u16,
- read_test_data_u32,
- read_test_data_u64 };
+read_ufn read_ufns[] = {
+ read_test_data_u16,
+ read_test_data_u32,
+#if __SIZEOF_POINTER__ >= 8
+ read_test_data_u64
+#endif
+};
bool do_unsigned_reads(int start_off)
{
@@ -476,10 +484,14 @@ bool do_signed_reads(bool neg_first)
return ok;
}
-init_ufn init_ufns[] = { init_test_data_u8,
- init_test_data_u16,
- init_test_data_u32,
- init_test_data_u64 };
+init_ufn init_ufns[] = {
+ init_test_data_u8,
+ init_test_data_u16,
+ init_test_data_u32,
+#if __SIZEOF_POINTER__ >= 8
+ init_test_data_u64
+#endif
+};
int main(void)
{
--
2.39.5
^ permalink raw reply related [flat|nested] 23+ messages in thread* [PULL 12/18] tests/tcg: ensure s390x-softmmu output redirected
2024-09-18 21:06 [PULL 00/18] tcg plugins (deprecations, mem apis, contrib plugins) Alex Bennée
` (10 preceding siblings ...)
2024-09-18 21:07 ` [PULL 11/18] tests/tcg: only read/write 64 bit words on 64 bit systems Alex Bennée
@ 2024-09-18 21:07 ` Alex Bennée
2024-09-18 21:07 ` [PULL 13/18] tests/tcg: add a system test to check memory instrumentation Alex Bennée
` (6 subsequent siblings)
18 siblings, 0 replies; 23+ messages in thread
From: Alex Bennée @ 2024-09-18 21:07 UTC (permalink / raw)
To: qemu-devel
Cc: Alex Bennée, Ilya Leoshkevich, Thomas Huth,
Richard Henderson, David Hildenbrand, open list:S390 TCG CPUs
The multiarch system tests output serial data which should be
redirected to the "output" chardev rather than echoed to the console.
Comment the use of EXTFLAGS variable while we are at it.
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240916085400.1046925-13-alex.bennee@linaro.org>
diff --git a/tests/tcg/s390x/Makefile.softmmu-target b/tests/tcg/s390x/Makefile.softmmu-target
index f60f94b090..be242ba8f1 100644
--- a/tests/tcg/s390x/Makefile.softmmu-target
+++ b/tests/tcg/s390x/Makefile.softmmu-target
@@ -1,6 +1,7 @@
S390X_SRC=$(SRC_PATH)/tests/tcg/s390x
VPATH+=$(S390X_SRC)
-QEMU_OPTS+=-action panic=exit-failure -nographic $(EXTFLAGS) -kernel
+# EXTFLAGS can be passed by the user, e.g. to override the --accel
+QEMU_OPTS+=-action panic=exit-failure -nographic -serial chardev:output $(EXTFLAGS) -kernel
LINK_SCRIPT=$(S390X_SRC)/softmmu.ld
CFLAGS+=-ggdb -O0
LDFLAGS=-nostdlib -static
--
2.39.5
^ permalink raw reply related [flat|nested] 23+ messages in thread* [PULL 13/18] tests/tcg: add a system test to check memory instrumentation
2024-09-18 21:06 [PULL 00/18] tcg plugins (deprecations, mem apis, contrib plugins) Alex Bennée
` (11 preceding siblings ...)
2024-09-18 21:07 ` [PULL 12/18] tests/tcg: ensure s390x-softmmu output redirected Alex Bennée
@ 2024-09-18 21:07 ` Alex Bennée
2024-09-18 21:07 ` [PULL 14/18] util/timer: avoid deadlock when shutting down Alex Bennée
` (5 subsequent siblings)
18 siblings, 0 replies; 23+ messages in thread
From: Alex Bennée @ 2024-09-18 21:07 UTC (permalink / raw)
To: qemu-devel
Cc: Alex Bennée, Pierrick Bouvier, Richard Henderson,
Alexandre Iooss, Mahmoud Mandour, David Hildenbrand,
Ilya Leoshkevich, open list:S390 TCG CPUs
At first I thought I could compile the user-mode test for system mode
however we already have a fairly comprehensive test case for system
mode in "memory" so lets use that.
As tracking every access will quickly build up with "print-access" we
add a new mode to track groups of reads and writes to regions. Because
the test_data is 16k aligned we can be sure all accesses to it are
ones we can count.
First we extend the test to report where the test_data region is. Then
we expand the pdot() function to track the total number of reads and
writes to the region. We have to add some addition pdot() calls to
take into account multiple reads/writes in the test loops.
Finally we add a python script to integrate the data from the plugin
and the output of the test and validate they both agree on the total
counts. As some boot codes clear the bss we also add a flag to add a
regions worth of writes to the expected total.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Message-Id: <20240916085400.1046925-14-alex.bennee@linaro.org>
diff --git a/tests/tcg/multiarch/system/memory.c b/tests/tcg/multiarch/system/memory.c
index 28080767b2..65a6038a24 100644
--- a/tests/tcg/multiarch/system/memory.c
+++ b/tests/tcg/multiarch/system/memory.c
@@ -14,26 +14,35 @@
#include <stdint.h>
#include <stdbool.h>
+#include <inttypes.h>
#include <minilib.h>
#ifndef CHECK_UNALIGNED
# error "Target does not specify CHECK_UNALIGNED"
#endif
+uint32_t test_read_count;
+uint32_t test_write_count;
+
#define MEM_PAGE_SIZE 4096 /* nominal 4k "pages" */
#define TEST_SIZE (MEM_PAGE_SIZE * 4) /* 4 pages */
#define ARRAY_SIZE(x) ((sizeof(x) / sizeof((x)[0])))
-__attribute__((aligned(MEM_PAGE_SIZE)))
+__attribute__((aligned(TEST_SIZE)))
static uint8_t test_data[TEST_SIZE];
typedef void (*init_ufn) (int offset);
typedef bool (*read_ufn) (int offset);
typedef bool (*read_sfn) (int offset, bool nf);
-static void pdot(int count)
+static void pdot(int count, bool write)
{
+ if (write) {
+ test_write_count++;
+ } else {
+ test_read_count++;
+ }
if (count % 128 == 0) {
ml_printf(".");
}
@@ -67,7 +76,7 @@ static void init_test_data_u8(int unused_offset)
for (i = 0; i < TEST_SIZE; i++) {
*ptr++ = BYTE_NEXT(count);
- pdot(i);
+ pdot(i, true);
}
ml_printf("done %d @ %p\n", i, ptr);
@@ -93,8 +102,9 @@ static void init_test_data_s8(bool neg_first)
neg_first ? "neg first" : "pos first");
for (i = 0; i < TEST_SIZE / 2; i++) {
*ptr++ = get_byte(i, neg_first);
+ pdot(i, true);
*ptr++ = get_byte(i, !neg_first);
- pdot(i);
+ pdot(i, true);
}
ml_printf("done %d @ %p\n", i * 2, ptr);
}
@@ -116,6 +126,7 @@ static void reset_start_data(int offset)
for (i = 0; i < offset; i++) {
*ptr++ = 0;
+ pdot(i, true);
}
ml_printf("done %d @ %p\n", i, ptr);
@@ -136,7 +147,7 @@ static void init_test_data_u16(int offset)
uint16_t low = BYTE_NEXT(count), high = BYTE_NEXT(count);
word = BYTE_SHIFT(high, 1) | BYTE_SHIFT(low, 0);
*ptr++ = word;
- pdot(i);
+ pdot(i, true);
}
ml_printf("done %d @ %p\n", i, ptr);
}
@@ -158,7 +169,7 @@ static void init_test_data_u32(int offset)
word = BYTE_SHIFT(b1, 3) | BYTE_SHIFT(b2, 2) | BYTE_SHIFT(b3, 1) |
BYTE_SHIFT(b4, 0);
*ptr++ = word;
- pdot(i);
+ pdot(i, true);
}
ml_printf("done %d @ %p\n", i, ptr);
}
@@ -184,7 +195,7 @@ static void init_test_data_u64(int offset)
BYTE_SHIFT(b4, 4) | BYTE_SHIFT(b5, 3) | BYTE_SHIFT(b6, 2) |
BYTE_SHIFT(b7, 1) | BYTE_SHIFT(b8, 0);
*ptr++ = word;
- pdot(i);
+ pdot(i, true);
}
ml_printf("done %d @ %p\n", i, ptr);
}
@@ -207,7 +218,7 @@ static bool read_test_data_u16(int offset)
ml_printf("Error %d < %d\n", high, low);
return false;
} else {
- pdot(i);
+ pdot(i, false);
}
}
@@ -249,7 +260,7 @@ static bool read_test_data_u32(int offset)
ml_printf("Error %d, %d, %d, %d", b1, b2, b3, b4);
return false;
} else {
- pdot(i);
+ pdot(i, false);
}
}
ml_printf("done %d @ %p\n", i, ptr);
@@ -304,7 +315,7 @@ static bool read_test_data_u64(int offset)
b1, b2, b3, b4, b5, b6, b7, b8);
return false;
} else {
- pdot(i);
+ pdot(i, false);
}
}
ml_printf("done %d @ %p\n", i, ptr);
@@ -376,9 +387,11 @@ static bool read_test_data_s8(int offset, bool neg_first)
second = *ptr++;
if (neg_first && first < 0 && second > 0) {
- pdot(i);
+ pdot(i, false);
+ pdot(i, false);
} else if (!neg_first && first > 0 && second < 0) {
- pdot(i);
+ pdot(i, false);
+ pdot(i, false);
} else {
ml_printf("Error %d %c %d\n", first, neg_first ? '<' : '>', second);
return false;
@@ -409,9 +422,9 @@ static bool read_test_data_s16(int offset, bool neg_first)
int32_t data = *ptr++;
if (neg_first && data < 0) {
- pdot(i);
+ pdot(i, false);
} else if (!neg_first && data > 0) {
- pdot(i);
+ pdot(i, false);
} else {
ml_printf("Error %d %c 0\n", data, neg_first ? '<' : '>');
return false;
@@ -442,9 +455,9 @@ static bool read_test_data_s32(int offset, bool neg_first)
int64_t data = *ptr++;
if (neg_first && data < 0) {
- pdot(i);
+ pdot(i, false);
} else if (!neg_first && data > 0) {
- pdot(i);
+ pdot(i, false);
} else {
ml_printf("Error %d %c 0\n", data, neg_first ? '<' : '>');
return false;
@@ -498,6 +511,9 @@ int main(void)
int i;
bool ok = true;
+ ml_printf("Test data start: 0x%"PRIxPTR"\n", &test_data[0]);
+ ml_printf("Test data end: 0x%"PRIxPTR"\n", &test_data[TEST_SIZE]);
+
/* Run through the unsigned tests first */
for (i = 0; i < ARRAY_SIZE(init_ufns) && ok; i++) {
ok = do_unsigned_test(init_ufns[i]);
@@ -513,6 +529,8 @@ int main(void)
ok = do_signed_reads(true);
}
+ ml_printf("Test data read: %"PRId32"\n", test_read_count);
+ ml_printf("Test data write: %"PRId32"\n", test_write_count);
ml_printf("Test complete: %s\n", ok ? "PASSED" : "FAILED");
return ok ? 0 : -1;
}
diff --git a/tests/tcg/plugins/mem.c b/tests/tcg/plugins/mem.c
index 086e6f5bdf..121210157f 100644
--- a/tests/tcg/plugins/mem.c
+++ b/tests/tcg/plugins/mem.c
@@ -9,6 +9,7 @@
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
+#include <endian.h>
#include <stdio.h>
#include <glib.h>
@@ -26,13 +27,47 @@ typedef struct {
const char *sym;
} InsnInfo;
+/*
+ * For the "memory" system test we need to track accesses to
+ * individual regions. We mirror the data written to the region and
+ * then check when it is read that it matches up.
+ *
+ * We do this as regions rather than pages to save on complications
+ * with page crossing and the fact the test only cares about the
+ * test_data region.
+ */
+static uint64_t region_size = 4096 * 4;
+static uint64_t region_mask;
+
+typedef struct {
+ uint64_t region_address;
+ uint64_t reads;
+ uint64_t writes;
+ uint8_t *data;
+ /* Did we see every write and read with correct values? */
+ bool seen_all;
+} RegionInfo;
+
static struct qemu_plugin_scoreboard *counts;
static qemu_plugin_u64 mem_count;
static qemu_plugin_u64 io_count;
-static bool do_inline, do_callback, do_print_accesses;
+static bool do_inline, do_callback, do_print_accesses, do_region_summary;
static bool do_haddr;
static enum qemu_plugin_mem_rw rw = QEMU_PLUGIN_MEM_RW;
+
+static GMutex lock;
+static GHashTable *regions;
+
+static gint addr_order(gconstpointer a, gconstpointer b)
+{
+ RegionInfo *na = (RegionInfo *) a;
+ RegionInfo *nb = (RegionInfo *) b;
+
+ return na->region_address > nb->region_address ? 1 : -1;
+}
+
+
static void plugin_exit(qemu_plugin_id_t id, void *p)
{
g_autoptr(GString) out = g_string_new("");
@@ -46,9 +81,133 @@ static void plugin_exit(qemu_plugin_id_t id, void *p)
qemu_plugin_u64_sum(io_count));
}
qemu_plugin_outs(out->str);
+
+
+ if (do_region_summary) {
+ GList *counts = g_hash_table_get_values(regions);
+
+ counts = g_list_sort(counts, addr_order);
+
+ g_string_printf(out, "Region Base, Reads, Writes, Seen all\n");
+
+ if (counts && g_list_next(counts)) {
+ for (/* counts */; counts; counts = counts->next) {
+ RegionInfo *ri = (RegionInfo *) counts->data;
+
+ g_string_append_printf(out,
+ "0x%016"PRIx64", "
+ "%"PRId64", %"PRId64", %s\n",
+ ri->region_address,
+ ri->reads,
+ ri->writes,
+ ri->seen_all ? "true" : "false");
+ }
+ }
+ qemu_plugin_outs(out->str);
+ }
+
qemu_plugin_scoreboard_free(counts);
}
+/*
+ * Update the region tracking info for the access. We split up accesses
+ * that span regions even though the plugin infrastructure will deliver
+ * it as a single access.
+ */
+static void update_region_info(uint64_t region, uint64_t offset,
+ qemu_plugin_meminfo_t meminfo,
+ qemu_plugin_mem_value value,
+ unsigned size)
+{
+ bool be = qemu_plugin_mem_is_big_endian(meminfo);
+ bool is_store = qemu_plugin_mem_is_store(meminfo);
+ RegionInfo *ri;
+ bool unseen_data = false;
+
+ g_assert(offset + size <= region_size);
+
+ g_mutex_lock(&lock);
+ ri = (RegionInfo *) g_hash_table_lookup(regions, GUINT_TO_POINTER(region));
+
+ if (!ri) {
+ ri = g_new0(RegionInfo, 1);
+ ri->region_address = region;
+ ri->data = g_malloc0(region_size);
+ ri->seen_all = true;
+ g_hash_table_insert(regions, GUINT_TO_POINTER(region), (gpointer) ri);
+ }
+
+ if (is_store) {
+ ri->writes++;
+ } else {
+ ri->reads++;
+ }
+
+ switch (value.type) {
+ case QEMU_PLUGIN_MEM_VALUE_U8:
+ if (is_store) {
+ ri->data[offset] = value.data.u8;
+ } else if (ri->data[offset] != value.data.u8) {
+ unseen_data = true;
+ }
+ break;
+ case QEMU_PLUGIN_MEM_VALUE_U16:
+ {
+ uint16_t *p = (uint16_t *) &ri->data[offset];
+ uint16_t val = be ? htobe16(value.data.u16) : htole16(value.data.u16);
+ if (is_store) {
+ *p = val;
+ } else if (*p != val) {
+ unseen_data = true;
+ }
+ break;
+ }
+ case QEMU_PLUGIN_MEM_VALUE_U32:
+ {
+ uint32_t *p = (uint32_t *) &ri->data[offset];
+ uint32_t val = be ? htobe32(value.data.u32) : htole32(value.data.u32);
+ if (is_store) {
+ *p = val;
+ } else if (*p != val) {
+ unseen_data = true;
+ }
+ break;
+ }
+ case QEMU_PLUGIN_MEM_VALUE_U64:
+ {
+ uint64_t *p = (uint64_t *) &ri->data[offset];
+ uint64_t val = be ? htobe64(value.data.u64) : htole64(value.data.u64);
+ if (is_store) {
+ *p = val;
+ } else if (*p != val) {
+ unseen_data = true;
+ }
+ break;
+ }
+ case QEMU_PLUGIN_MEM_VALUE_U128:
+ /* non in test so skip */
+ break;
+ default:
+ g_assert_not_reached();
+ }
+
+ /*
+ * This is expected for regions initialised by QEMU (.text etc) but we
+ * expect to see all data read and written to the test_data region
+ * of the memory test.
+ */
+ if (unseen_data && ri->seen_all) {
+ g_autoptr(GString) error = g_string_new("Warning: ");
+ g_string_append_printf(error, "0x%016"PRIx64":%"PRId64
+ " read an un-instrumented value\n",
+ region, offset);
+ qemu_plugin_outs(error->str);
+ ri->seen_all = false;
+ }
+
+ g_mutex_unlock(&lock);
+}
+
static void vcpu_mem(unsigned int cpu_index, qemu_plugin_meminfo_t meminfo,
uint64_t vaddr, void *udata)
{
@@ -63,6 +222,15 @@ static void vcpu_mem(unsigned int cpu_index, qemu_plugin_meminfo_t meminfo,
} else {
qemu_plugin_u64_add(mem_count, cpu_index, 1);
}
+
+ if (do_region_summary) {
+ uint64_t region = vaddr & ~region_mask;
+ uint64_t offset = vaddr & region_mask;
+ qemu_plugin_mem_value value = qemu_plugin_mem_get_value(meminfo);
+ unsigned size = 1 << qemu_plugin_mem_size_shift(meminfo);
+
+ update_region_info(region, offset, meminfo, value, size);
+ }
}
static void print_access(unsigned int cpu_index, qemu_plugin_meminfo_t meminfo,
@@ -117,7 +285,7 @@ static void vcpu_tb_trans(qemu_plugin_id_t id, struct qemu_plugin_tb *tb)
QEMU_PLUGIN_INLINE_ADD_U64,
mem_count, 1);
}
- if (do_callback) {
+ if (do_callback || do_region_summary) {
qemu_plugin_register_vcpu_mem_cb(insn, vcpu_mem,
QEMU_PLUGIN_CB_NO_REGS,
rw, NULL);
@@ -176,6 +344,12 @@ QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plugin_id_t id,
fprintf(stderr, "boolean argument parsing failed: %s\n", opt);
return -1;
}
+ } else if (g_strcmp0(tokens[0], "region-summary") == 0) {
+ if (!qemu_plugin_bool_parse(tokens[0], tokens[1],
+ &do_region_summary)) {
+ fprintf(stderr, "boolean argument parsing failed: %s\n", opt);
+ return -1;
+ }
} else {
fprintf(stderr, "option parsing failed: %s\n", opt);
return -1;
@@ -196,6 +370,11 @@ QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plugin_id_t id,
qemu_plugin_outs(out->str);
}
+ if (do_region_summary) {
+ region_mask = (region_size - 1);
+ regions = g_hash_table_new(NULL, g_direct_equal);
+ }
+
counts = qemu_plugin_scoreboard_new(sizeof(CPUCount));
mem_count = qemu_plugin_scoreboard_u64_in_struct(
counts, CPUCount, mem_count);
diff --git a/tests/tcg/alpha/Makefile.softmmu-target b/tests/tcg/alpha/Makefile.softmmu-target
index a0eca4d6ea..a944102a3c 100644
--- a/tests/tcg/alpha/Makefile.softmmu-target
+++ b/tests/tcg/alpha/Makefile.softmmu-target
@@ -28,7 +28,7 @@ LDFLAGS+=-static -nostdlib $(CRT_OBJS) $(MINILIB_OBJS) -lgcc
%: %.c $(LINK_SCRIPT) $(CRT_OBJS) $(MINILIB_OBJS)
$(CC) $(CFLAGS) $(EXTRA_CFLAGS) $< -o $@ $(LDFLAGS)
-memory: CFLAGS+=-DCHECK_UNALIGNED=0
+memory: CFLAGS+=-DCHECK_UNALIGNED=0 -mbwx
# Running
QEMU_OPTS+=-serial chardev:output -kernel
diff --git a/tests/tcg/multiarch/system/Makefile.softmmu-target b/tests/tcg/multiarch/system/Makefile.softmmu-target
index 32dc0f9830..07be001102 100644
--- a/tests/tcg/multiarch/system/Makefile.softmmu-target
+++ b/tests/tcg/multiarch/system/Makefile.softmmu-target
@@ -65,3 +65,9 @@ endif
MULTIARCH_RUNS += run-gdbstub-memory run-gdbstub-interrupt \
run-gdbstub-untimely-packet run-gdbstub-registers
+
+# Test plugin memory access instrumentation
+run-plugin-memory-with-libmem.so: \
+ PLUGIN_ARGS=$(COMMA)region-summary=true
+run-plugin-memory-with-libmem.so: \
+ CHECK_PLUGIN_OUTPUT_COMMAND=$(MULTIARCH_SYSTEM_SRC)/validate-memory-counts.py $@.out
diff --git a/tests/tcg/multiarch/system/validate-memory-counts.py b/tests/tcg/multiarch/system/validate-memory-counts.py
new file mode 100755
index 0000000000..5b8bbf3ef3
--- /dev/null
+++ b/tests/tcg/multiarch/system/validate-memory-counts.py
@@ -0,0 +1,130 @@
+#!/usr/bin/env python3
+#
+# validate-memory-counts.py: check we instrumented memory properly
+#
+# This program takes two inputs:
+# - the mem plugin output
+# - the memory binary output
+#
+# Copyright (C) 2024 Linaro Ltd
+#
+# SPDX-License-Identifier: GPL-2.0-or-later
+
+import sys
+from argparse import ArgumentParser
+
+def extract_counts(path):
+ """
+ Load the output from path and extract the lines containing:
+
+ Test data start: 0x40214000
+ Test data end: 0x40218001
+ Test data read: 2522280
+ Test data write: 262111
+
+ From the stream of data. Extract the values for use in the
+ validation function.
+ """
+ start_address = None
+ end_address = None
+ read_count = 0
+ write_count = 0
+ with open(path, 'r') as f:
+ for line in f:
+ if line.startswith("Test data start:"):
+ start_address = int(line.split(':')[1].strip(), 16)
+ elif line.startswith("Test data end:"):
+ end_address = int(line.split(':')[1].strip(), 16)
+ elif line.startswith("Test data read:"):
+ read_count = int(line.split(':')[1].strip())
+ elif line.startswith("Test data write:"):
+ write_count = int(line.split(':')[1].strip())
+ return start_address, end_address, read_count, write_count
+
+
+def parse_plugin_output(path, start, end):
+ """
+ Load the plugin output from path in the form of:
+
+ Region Base, Reads, Writes, Seen all
+ 0x0000000040004000, 31093, 0, false
+ 0x0000000040214000, 2522280, 278579, true
+ 0x0000000040000000, 137398, 0, false
+ 0x0000000040210000, 54727397, 33721956, false
+
+ And extract the ranges that match test data start and end and
+ return the results.
+ """
+ total_reads = 0
+ total_writes = 0
+ seen_all = False
+
+ with open(path, 'r') as f:
+ next(f) # Skip the header
+ for line in f:
+
+ if line.startswith("Region Base"):
+ continue
+
+ parts = line.strip().split(', ')
+ if len(parts) != 4:
+ continue
+
+ region_base = int(parts[0], 16)
+ reads = int(parts[1])
+ writes = int(parts[2])
+
+ if start <= region_base < end: # Checking if within range
+ total_reads += reads
+ total_writes += writes
+ seen_all = parts[3] == "true"
+
+ return total_reads, total_writes, seen_all
+
+def main() -> None:
+ """
+ Process the arguments, injest the program and plugin out and
+ verify they match up and report if they do not.
+ """
+ parser = ArgumentParser(description="Validate memory instrumentation")
+ parser.add_argument('test_output',
+ help="The output from the test itself")
+ parser.add_argument('plugin_output',
+ help="The output from memory plugin")
+ parser.add_argument('--bss-cleared',
+ action='store_true',
+ help='Assume bss was cleared (and adjusts counts).')
+
+ args = parser.parse_args()
+
+ # Extract counts from memory binary
+ start, end, exp_reads, exp_writes = extract_counts(args.test_output)
+
+ # Some targets clear BSS before running but the test doesn't know
+ # that so we adjust it by the size of the test region.
+ if args.bss_cleared:
+ exp_writes += 16384
+
+ if start is None or end is None:
+ print("Failed to test_data boundaries from output.")
+ sys.exit(1)
+
+ # Parse plugin output
+ preads, pwrites, seen_all = parse_plugin_output(args.plugin_output,
+ start, end)
+
+ if not seen_all:
+ print("Fail: didn't instrument all accesses to test_data.")
+ sys.exit(1)
+
+ # Compare and report
+ if preads == exp_reads and pwrites == exp_writes:
+ sys.exit(0)
+ else:
+ print("Fail: The memory reads and writes count does not match.")
+ print(f"Expected Reads: {exp_reads}, Actual Reads: {preads}")
+ print(f"Expected Writes: {exp_writes}, Actual Writes: {pwrites}")
+ sys.exit(1)
+
+if __name__ == "__main__":
+ main()
diff --git a/tests/tcg/s390x/Makefile.softmmu-target b/tests/tcg/s390x/Makefile.softmmu-target
index be242ba8f1..3227903348 100644
--- a/tests/tcg/s390x/Makefile.softmmu-target
+++ b/tests/tcg/s390x/Makefile.softmmu-target
@@ -47,3 +47,8 @@ $(MULTIARCH_TESTS): $(S390X_MULTIARCH_RUNTIME_OBJS)
$(MULTIARCH_TESTS): LDFLAGS += $(S390X_MULTIARCH_RUNTIME_OBJS)
$(MULTIARCH_TESTS): CFLAGS += $(MINILIB_INC)
memory: CFLAGS += -DCHECK_UNALIGNED=0
+
+# s390x clears the BSS section so we need to account for that
+run-plugin-memory-with-libmem.so: \
+ CHECK_PLUGIN_OUTPUT_COMMAND=$(MULTIARCH_SYSTEM_SRC)/validate-memory-counts.py \
+ --bss-cleared $@.out
--
2.39.5
^ permalink raw reply related [flat|nested] 23+ messages in thread* [PULL 14/18] util/timer: avoid deadlock when shutting down
2024-09-18 21:06 [PULL 00/18] tcg plugins (deprecations, mem apis, contrib plugins) Alex Bennée
` (12 preceding siblings ...)
2024-09-18 21:07 ` [PULL 13/18] tests/tcg: add a system test to check memory instrumentation Alex Bennée
@ 2024-09-18 21:07 ` Alex Bennée
2024-09-18 21:07 ` [PULL 15/18] contrib/plugins: Add a plugin to generate basic block vectors Alex Bennée
` (4 subsequent siblings)
18 siblings, 0 replies; 23+ messages in thread
From: Alex Bennée @ 2024-09-18 21:07 UTC (permalink / raw)
To: qemu-devel
Cc: Alex Bennée, Elisha Hollander, Pierrick Bouvier,
Paolo Bonzini
When we shut down a guest we disable the timers. However this can
cause deadlock if the guest has queued some async work that is trying
to advance system time and spins forever trying to wind time forward.
Pay attention to the return code and bail early if we can't wind time
forward.
Reported-by: Elisha Hollander <just4now666666@gmail.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Message-Id: <20240916085400.1046925-15-alex.bennee@linaro.org>
diff --git a/util/qemu-timer.c b/util/qemu-timer.c
index 213114be68..6b1533bc2a 100644
--- a/util/qemu-timer.c
+++ b/util/qemu-timer.c
@@ -685,10 +685,17 @@ int64_t qemu_clock_advance_virtual_time(int64_t dest)
{
int64_t clock = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
AioContext *aio_context;
+ int64_t deadline;
+
aio_context = qemu_get_aio_context();
- while (clock < dest) {
- int64_t deadline = qemu_clock_deadline_ns_all(QEMU_CLOCK_VIRTUAL,
+
+ deadline = qemu_clock_deadline_ns_all(QEMU_CLOCK_VIRTUAL,
QEMU_TIMER_ATTR_ALL);
+ /*
+ * A deadline of < 0 indicates this timer is not enabled, so we
+ * won't get far trying to run it forward.
+ */
+ while (deadline >= 0 && clock < dest) {
int64_t warp = qemu_soonest_timeout(dest - clock, deadline);
qemu_virtual_clock_set_ns(qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + warp);
@@ -696,6 +703,9 @@ int64_t qemu_clock_advance_virtual_time(int64_t dest)
qemu_clock_run_timers(QEMU_CLOCK_VIRTUAL);
timerlist_run_timers(aio_context->tlg.tl[QEMU_CLOCK_VIRTUAL]);
clock = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+
+ deadline = qemu_clock_deadline_ns_all(QEMU_CLOCK_VIRTUAL,
+ QEMU_TIMER_ATTR_ALL);
}
qemu_clock_notify(QEMU_CLOCK_VIRTUAL);
--
2.39.5
^ permalink raw reply related [flat|nested] 23+ messages in thread* [PULL 15/18] contrib/plugins: Add a plugin to generate basic block vectors
2024-09-18 21:06 [PULL 00/18] tcg plugins (deprecations, mem apis, contrib plugins) Alex Bennée
` (13 preceding siblings ...)
2024-09-18 21:07 ` [PULL 14/18] util/timer: avoid deadlock when shutting down Alex Bennée
@ 2024-09-18 21:07 ` Alex Bennée
2024-09-18 21:07 ` [PULL 16/18] plugins: add plugin API to read guest memory Alex Bennée
` (3 subsequent siblings)
18 siblings, 0 replies; 23+ messages in thread
From: Alex Bennée @ 2024-09-18 21:07 UTC (permalink / raw)
To: qemu-devel
Cc: Akihiko Odaki, Yotaro Nada, Pierrick Bouvier, Alex Bennée,
Alexandre Iooss, Mahmoud Mandour
From: Akihiko Odaki <akihiko.odaki@daynix.com>
SimPoint is a widely used tool to find the ideal microarchitecture
simulation points so Valgrind[2] and Pin[3] support generating basic
block vectors for use with them. Let's add a corresponding plugin to
QEMU too.
Note that this plugin has a different goal with tests/plugin/bb.c.
This plugin creates a vector for each constant interval instead of
counting the execution of basic blocks for the entire run and able to
describe the change of execution behavior. Its output is also
syntactically simple and better suited for parsing, while the output of
tests/plugin/bb.c is more human-readable.
[1] https://cseweb.ucsd.edu/~calder/simpoint/
[2] https://valgrind.org/docs/manual/bbv-manual.html
[3] https://www.intel.com/content/www/us/en/developer/articles/tool/pin-a-dynamic-binary-instrumentation-tool.html
Signed-off-by: Yotaro Nada <yotaro.nada@gmail.com>
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Message-Id: <20240816-bb-v3-1-b9aa4a5c75c5@daynix.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240916085400.1046925-16-alex.bennee@linaro.org>
diff --git a/docs/about/emulation.rst b/docs/about/emulation.rst
index 05f54d3f27..ee59c2fa9b 100644
--- a/docs/about/emulation.rst
+++ b/docs/about/emulation.rst
@@ -268,6 +268,36 @@ Behaviour can be tweaked with the following arguments:
* - idle=true|false
- Dump the current execution stats whenever the guest vCPU idles
+Basic Block Vectors
+...................
+
+``contrib/plugins/bbv.c``
+
+The bbv plugin allows you to generate basic block vectors for use with the
+`SimPoint <https://cseweb.ucsd.edu/~calder/simpoint/>`__ analysis tool.
+
+.. list-table:: Basic block vectors arguments
+ :widths: 20 80
+ :header-rows: 1
+
+ * - Option
+ - Description
+ * - interval=N
+ - The interval to generate a basic block vector specified by the number of
+ instructions (Default: N = 100000000)
+ * - outfile=PATH
+ - The path to output files.
+ It will be suffixed with ``.N.bb`` where ``N`` is a vCPU index.
+
+Example::
+
+ $ qemu-aarch64 \
+ -plugin contrib/plugins/libbbv.so,interval=100,outfile=sha1 \
+ tests/tcg/aarch64-linux-user/sha1
+ SHA1=15dd99a1991e0b3826fede3deffc1feba42278e6
+ $ du sha1.0.bb
+ 23128 sha1.0.bb
+
Instruction
...........
diff --git a/contrib/plugins/bbv.c b/contrib/plugins/bbv.c
new file mode 100644
index 0000000000..a5256517dd
--- /dev/null
+++ b/contrib/plugins/bbv.c
@@ -0,0 +1,158 @@
+/*
+ * Generate basic block vectors for use with the SimPoint analysis tool.
+ * SimPoint: https://cseweb.ucsd.edu/~calder/simpoint/
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include <stdio.h>
+#include <glib.h>
+
+#include <qemu-plugin.h>
+
+typedef struct Bb {
+ uint64_t vaddr;
+ struct qemu_plugin_scoreboard *count;
+ unsigned int index;
+} Bb;
+
+typedef struct Vcpu {
+ uint64_t count;
+ FILE *file;
+} Vcpu;
+
+QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION;
+static GHashTable *bbs;
+static GRWLock bbs_lock;
+static char *filename;
+static struct qemu_plugin_scoreboard *vcpus;
+static uint64_t interval = 100000000;
+
+static void plugin_exit(qemu_plugin_id_t id, void *p)
+{
+ for (int i = 0; i < qemu_plugin_num_vcpus(); i++) {
+ fclose(((Vcpu *)qemu_plugin_scoreboard_find(vcpus, i))->file);
+ }
+
+ g_hash_table_unref(bbs);
+ g_free(filename);
+ qemu_plugin_scoreboard_free(vcpus);
+}
+
+static void free_bb(void *data)
+{
+ qemu_plugin_scoreboard_free(((Bb *)data)->count);
+ g_free(data);
+}
+
+static qemu_plugin_u64 count_u64(void)
+{
+ return qemu_plugin_scoreboard_u64_in_struct(vcpus, Vcpu, count);
+}
+
+static qemu_plugin_u64 bb_count_u64(Bb *bb)
+{
+ return qemu_plugin_scoreboard_u64(bb->count);
+}
+
+static void vcpu_init(qemu_plugin_id_t id, unsigned int vcpu_index)
+{
+ g_autofree gchar *vcpu_filename = NULL;
+ Vcpu *vcpu = qemu_plugin_scoreboard_find(vcpus, vcpu_index);
+
+ vcpu_filename = g_strdup_printf("%s.%u.bb", filename, vcpu_index);
+ vcpu->file = fopen(vcpu_filename, "w");
+}
+
+static void vcpu_interval_exec(unsigned int vcpu_index, void *udata)
+{
+ Vcpu *vcpu = qemu_plugin_scoreboard_find(vcpus, vcpu_index);
+ GHashTableIter iter;
+ void *value;
+
+ if (!vcpu->file) {
+ return;
+ }
+
+ vcpu->count -= interval;
+
+ fputc('T', vcpu->file);
+
+ g_rw_lock_reader_lock(&bbs_lock);
+ g_hash_table_iter_init(&iter, bbs);
+
+ while (g_hash_table_iter_next(&iter, NULL, &value)) {
+ Bb *bb = value;
+ uint64_t bb_count = qemu_plugin_u64_get(bb_count_u64(bb), vcpu_index);
+
+ if (!bb_count) {
+ continue;
+ }
+
+ fprintf(vcpu->file, ":%u:%" PRIu64 " ", bb->index, bb_count);
+ qemu_plugin_u64_set(bb_count_u64(bb), vcpu_index, 0);
+ }
+
+ g_rw_lock_reader_unlock(&bbs_lock);
+ fputc('\n', vcpu->file);
+}
+
+static void vcpu_tb_trans(qemu_plugin_id_t id, struct qemu_plugin_tb *tb)
+{
+ uint64_t n_insns = qemu_plugin_tb_n_insns(tb);
+ uint64_t vaddr = qemu_plugin_tb_vaddr(tb);
+ Bb *bb;
+
+ g_rw_lock_writer_lock(&bbs_lock);
+ bb = g_hash_table_lookup(bbs, &vaddr);
+ if (!bb) {
+ bb = g_new(Bb, 1);
+ bb->vaddr = vaddr;
+ bb->count = qemu_plugin_scoreboard_new(sizeof(uint64_t));
+ bb->index = g_hash_table_size(bbs);
+ g_hash_table_replace(bbs, &bb->vaddr, bb);
+ }
+ g_rw_lock_writer_unlock(&bbs_lock);
+
+ qemu_plugin_register_vcpu_tb_exec_inline_per_vcpu(
+ tb, QEMU_PLUGIN_INLINE_ADD_U64, count_u64(), n_insns);
+
+ qemu_plugin_register_vcpu_tb_exec_inline_per_vcpu(
+ tb, QEMU_PLUGIN_INLINE_ADD_U64, bb_count_u64(bb), n_insns);
+
+ qemu_plugin_register_vcpu_tb_exec_cond_cb(
+ tb, vcpu_interval_exec, QEMU_PLUGIN_CB_NO_REGS,
+ QEMU_PLUGIN_COND_GE, count_u64(), interval, NULL);
+}
+
+QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plugin_id_t id,
+ const qemu_info_t *info,
+ int argc, char **argv)
+{
+ for (int i = 0; i < argc; i++) {
+ char *opt = argv[i];
+ g_auto(GStrv) tokens = g_strsplit(opt, "=", 2);
+ if (g_strcmp0(tokens[0], "interval") == 0) {
+ interval = g_ascii_strtoull(tokens[1], NULL, 10);
+ } else if (g_strcmp0(tokens[0], "outfile") == 0) {
+ filename = tokens[1];
+ tokens[1] = NULL;
+ } else {
+ fprintf(stderr, "option parsing failed: %s\n", opt);
+ return -1;
+ }
+ }
+
+ if (!filename) {
+ fputs("outfile unspecified\n", stderr);
+ return -1;
+ }
+
+ bbs = g_hash_table_new_full(g_int64_hash, g_int64_equal, NULL, free_bb);
+ vcpus = qemu_plugin_scoreboard_new(sizeof(Vcpu));
+ qemu_plugin_register_atexit_cb(id, plugin_exit, NULL);
+ qemu_plugin_register_vcpu_init_cb(id, vcpu_init);
+ qemu_plugin_register_vcpu_tb_trans_cb(id, vcpu_tb_trans);
+
+ return 0;
+}
diff --git a/contrib/plugins/Makefile b/contrib/plugins/Makefile
index d4ac599f93..bbddd4800f 100644
--- a/contrib/plugins/Makefile
+++ b/contrib/plugins/Makefile
@@ -13,6 +13,7 @@ TOP_SRC_PATH = $(SRC_PATH)/../..
VPATH += $(SRC_PATH)
NAMES :=
+NAMES += bbv
NAMES += execlog
NAMES += hotblocks
NAMES += hotpages
--
2.39.5
^ permalink raw reply related [flat|nested] 23+ messages in thread* [PULL 16/18] plugins: add plugin API to read guest memory
2024-09-18 21:06 [PULL 00/18] tcg plugins (deprecations, mem apis, contrib plugins) Alex Bennée
` (14 preceding siblings ...)
2024-09-18 21:07 ` [PULL 15/18] contrib/plugins: Add a plugin to generate basic block vectors Alex Bennée
@ 2024-09-18 21:07 ` Alex Bennée
2024-09-18 21:07 ` [PULL 17/18] plugins: add option to dump write argument to syscall plugin Alex Bennée
` (2 subsequent siblings)
18 siblings, 0 replies; 23+ messages in thread
From: Alex Bennée @ 2024-09-18 21:07 UTC (permalink / raw)
To: qemu-devel
Cc: Rowan Hart, Pierrick Bouvier, Alex Bennée, Alexandre Iooss,
Mahmoud Mandour
From: Rowan Hart <rowanbhart@gmail.com>
Signed-off-by: Rowan Hart <rowanbhart@gmail.com>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Message-Id: <20240827215329.248434-2-rowanbhart@gmail.com>
[AJB: tweaked cpu_memory_rw_debug call]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240916085400.1046925-17-alex.bennee@linaro.org>
diff --git a/include/qemu/qemu-plugin.h b/include/qemu/qemu-plugin.h
index 649ce89815..622c9a0232 100644
--- a/include/qemu/qemu-plugin.h
+++ b/include/qemu/qemu-plugin.h
@@ -57,11 +57,19 @@ typedef uint64_t qemu_plugin_id_t;
* - Remove qemu_plugin_register_vcpu_{tb, insn, mem}_exec_inline.
* Those functions are replaced by *_per_vcpu variants, which guarantee
* thread-safety for operations.
+ *
+ * version 3:
+ * - modified arguments and return value of qemu_plugin_insn_data to copy
+ * the data into a user-provided buffer instead of returning a pointer
+ * to the data.
+ *
+ * version 4:
+ * - added qemu_plugin_read_memory_vaddr
*/
extern QEMU_PLUGIN_EXPORT int qemu_plugin_version;
-#define QEMU_PLUGIN_VERSION 3
+#define QEMU_PLUGIN_VERSION 4
/**
* struct qemu_info_t - system information for plugins
@@ -884,6 +892,28 @@ typedef struct {
QEMU_PLUGIN_API
GArray *qemu_plugin_get_registers(void);
+/**
+ * qemu_plugin_read_memory_vaddr() - read from memory using a virtual address
+ *
+ * @addr: A virtual address to read from
+ * @data: A byte array to store data into
+ * @len: The number of bytes to read, starting from @addr
+ *
+ * @len bytes of data is read starting at @addr and stored into @data. If @data
+ * is not large enough to hold @len bytes, it will be expanded to the necessary
+ * size, reallocating if necessary. @len must be greater than 0.
+ *
+ * This function does not ensure writes are flushed prior to reading, so
+ * callers should take care when calling this function in plugin callbacks to
+ * avoid attempting to read data which may not yet be written and should use
+ * the memory callback API instead.
+ *
+ * Returns true on success and false on failure.
+ */
+QEMU_PLUGIN_API
+bool qemu_plugin_read_memory_vaddr(uint64_t addr,
+ GByteArray *data, size_t len);
+
/**
* qemu_plugin_read_register() - read register for current vCPU
*
diff --git a/plugins/api.c b/plugins/api.c
index 3316d4a04d..24ea64e2de 100644
--- a/plugins/api.c
+++ b/plugins/api.c
@@ -560,6 +560,26 @@ GArray *qemu_plugin_get_registers(void)
return create_register_handles(regs);
}
+bool qemu_plugin_read_memory_vaddr(vaddr addr, GByteArray *data, size_t len)
+{
+ g_assert(current_cpu);
+
+ if (len == 0) {
+ return false;
+ }
+
+ g_byte_array_set_size(data, len);
+
+ int result = cpu_memory_rw_debug(current_cpu, addr, data->data,
+ data->len, false);
+
+ if (result < 0) {
+ return false;
+ }
+
+ return true;
+}
+
int qemu_plugin_read_register(struct qemu_plugin_register *reg, GByteArray *buf)
{
g_assert(current_cpu);
diff --git a/plugins/qemu-plugins.symbols b/plugins/qemu-plugins.symbols
index eed9d8abd9..032661f9ea 100644
--- a/plugins/qemu-plugins.symbols
+++ b/plugins/qemu-plugins.symbols
@@ -21,6 +21,7 @@
qemu_plugin_num_vcpus;
qemu_plugin_outs;
qemu_plugin_path_to_binary;
+ qemu_plugin_read_memory_vaddr;
qemu_plugin_read_register;
qemu_plugin_register_atexit_cb;
qemu_plugin_register_flush_cb;
--
2.39.5
^ permalink raw reply related [flat|nested] 23+ messages in thread* [PULL 17/18] plugins: add option to dump write argument to syscall plugin
2024-09-18 21:06 [PULL 00/18] tcg plugins (deprecations, mem apis, contrib plugins) Alex Bennée
` (15 preceding siblings ...)
2024-09-18 21:07 ` [PULL 16/18] plugins: add plugin API to read guest memory Alex Bennée
@ 2024-09-18 21:07 ` Alex Bennée
2024-09-18 21:07 ` [PULL 18/18] contrib/plugins: avoid hanging program Alex Bennée
2024-09-19 9:50 ` [PULL 00/18] tcg plugins (deprecations, mem apis, contrib plugins) Peter Maydell
18 siblings, 0 replies; 23+ messages in thread
From: Alex Bennée @ 2024-09-18 21:07 UTC (permalink / raw)
To: qemu-devel
Cc: Rowan Hart, Pierrick Bouvier, Alex Bennée, Alexandre Iooss,
Mahmoud Mandour
From: Rowan Hart <rowanbhart@gmail.com>
Signed-off-by: Rowan Hart <rowanbhart@gmail.com>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Tested-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Message-Id: <20240827215329.248434-3-rowanbhart@gmail.com>
[AJB: tweak fmt string for vaddr]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240916085400.1046925-18-alex.bennee@linaro.org>
diff --git a/docs/about/emulation.rst b/docs/about/emulation.rst
index ee59c2fa9b..3028d5fff7 100644
--- a/docs/about/emulation.rst
+++ b/docs/about/emulation.rst
@@ -414,6 +414,19 @@ run::
160 1 0
135 1 0
+Behaviour can be tweaked with the following arguments:
+
+.. list-table:: Syscall plugin arguments
+ :widths: 20 80
+ :header-rows: 1
+
+ * - Option
+ - Description
+ * - print=true|false
+ - Print the number of times each syscall is called
+ * - log_writes=true|false
+ - Log the buffer of each write syscall in hexdump format
+
Test inline operations
......................
@@ -803,4 +816,3 @@ Other emulation features
When running system emulation you can also enable deterministic
execution which allows for repeatable record/replay debugging. See
:ref:`Record/Replay<replay>` for more details.
-
diff --git a/tests/tcg/plugins/syscall.c b/tests/tcg/plugins/syscall.c
index 72e1a5bf90..89dc7f49b1 100644
--- a/tests/tcg/plugins/syscall.c
+++ b/tests/tcg/plugins/syscall.c
@@ -22,8 +22,57 @@ typedef struct {
int64_t errors;
} SyscallStats;
+struct SyscallInfo {
+ const char *name;
+ int64_t write_sysno;
+};
+
+static const struct SyscallInfo arch_syscall_info[] = {
+ { "aarch64", 64 },
+ { "aarch64_be", 64 },
+ { "alpha", 4 },
+ { "arm", 4 },
+ { "armeb", 4 },
+ { "avr", -1 },
+ { "cris", -1 },
+ { "hexagon", 64 },
+ { "hppa", -1 },
+ { "i386", 4 },
+ { "loongarch64", -1 },
+ { "m68k", 4 },
+ { "microblaze", 4 },
+ { "microblazeel", 4 },
+ { "mips", 1 },
+ { "mips64", 1 },
+ { "mips64el", 1 },
+ { "mipsel", 1 },
+ { "mipsn32", 1 },
+ { "mipsn32el", 1 },
+ { "or1k", -1 },
+ { "ppc", 4 },
+ { "ppc64", 4 },
+ { "ppc64le", 4 },
+ { "riscv32", 64 },
+ { "riscv64", 64 },
+ { "rx", -1 },
+ { "s390x", -1 },
+ { "sh4", -1 },
+ { "sh4eb", -1 },
+ { "sparc", 4 },
+ { "sparc32plus", 4 },
+ { "sparc64", 4 },
+ { "tricore", -1 },
+ { "x86_64", 1 },
+ { "xtensa", 13 },
+ { "xtensaeb", 13 },
+ { NULL, -1 },
+};
+
static GMutex lock;
static GHashTable *statistics;
+static GByteArray *memory_buffer;
+static bool do_log_writes;
+static int64_t write_sysno = -1;
static SyscallStats *get_or_create_entry(int64_t num)
{
@@ -39,6 +88,44 @@ static SyscallStats *get_or_create_entry(int64_t num)
return entry;
}
+/*
+ * Hex-dump a GByteArray to the QEMU plugin output in the format:
+ * 61 63 63 65 6c 09 09 20 20 20 66 70 75 09 09 09 | accel.....fpu...
+ * 20 6d 6f 64 75 6c 65 2d 63 6f 6d 6d 6f 6e 2e 63 | .module-common.c
+ */
+static void hexdump(const GByteArray *data)
+{
+ g_autoptr(GString) out = g_string_new("");
+
+ for (guint index = 0; index < data->len; index += 16) {
+ for (guint col = 0; col < 16; col++) {
+ if (index + col < data->len) {
+ g_string_append_printf(out, "%02x ", data->data[index + col]);
+ } else {
+ g_string_append(out, " ");
+ }
+ }
+
+ g_string_append(out, " | ");
+
+ for (guint col = 0; col < 16; col++) {
+ if (index + col >= data->len) {
+ break;
+ }
+
+ if (g_ascii_isgraph(data->data[index + col])) {
+ g_string_append_printf(out, "%c", data->data[index + col]);
+ } else {
+ g_string_append(out, ".");
+ }
+ }
+
+ g_string_append(out, "\n");
+ }
+
+ qemu_plugin_outs(out->str);
+}
+
static void vcpu_syscall(qemu_plugin_id_t id, unsigned int vcpu_index,
int64_t num, uint64_t a1, uint64_t a2,
uint64_t a3, uint64_t a4, uint64_t a5,
@@ -54,6 +141,14 @@ static void vcpu_syscall(qemu_plugin_id_t id, unsigned int vcpu_index,
g_autofree gchar *out = g_strdup_printf("syscall #%" PRIi64 "\n", num);
qemu_plugin_outs(out);
}
+
+ if (do_log_writes && num == write_sysno) {
+ if (qemu_plugin_read_memory_vaddr(a2, memory_buffer, a3)) {
+ hexdump(memory_buffer);
+ } else {
+ fprintf(stderr, "Error reading memory from vaddr %"PRIu64"\n", a2);
+ }
+ }
}
static void vcpu_syscall_ret(qemu_plugin_id_t id, unsigned int vcpu_idx,
@@ -127,6 +222,10 @@ QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plugin_id_t id,
if (!qemu_plugin_bool_parse(tokens[0], tokens[1], &do_print)) {
fprintf(stderr, "boolean argument parsing failed: %s\n", opt);
}
+ } else if (g_strcmp0(tokens[0], "log_writes") == 0) {
+ if (!qemu_plugin_bool_parse(tokens[0], tokens[1], &do_log_writes)) {
+ fprintf(stderr, "boolean argument parsing failed: %s\n", opt);
+ }
} else {
fprintf(stderr, "unsupported argument: %s\n", argv[i]);
return -1;
@@ -137,6 +236,24 @@ QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plugin_id_t id,
statistics = g_hash_table_new_full(NULL, g_direct_equal, NULL, g_free);
}
+ if (do_log_writes) {
+ for (const struct SyscallInfo *syscall_info = arch_syscall_info;
+ syscall_info->name != NULL; syscall_info++) {
+
+ if (g_strcmp0(syscall_info->name, info->target_name) == 0) {
+ write_sysno = syscall_info->write_sysno;
+ break;
+ }
+ }
+
+ if (write_sysno == -1) {
+ fprintf(stderr, "write syscall number not found\n");
+ return -1;
+ }
+
+ memory_buffer = g_byte_array_new();
+ }
+
qemu_plugin_register_vcpu_syscall_cb(id, vcpu_syscall);
qemu_plugin_register_vcpu_syscall_ret_cb(id, vcpu_syscall_ret);
qemu_plugin_register_atexit_cb(id, plugin_exit, NULL);
--
2.39.5
^ permalink raw reply related [flat|nested] 23+ messages in thread* [PULL 18/18] contrib/plugins: avoid hanging program
2024-09-18 21:06 [PULL 00/18] tcg plugins (deprecations, mem apis, contrib plugins) Alex Bennée
` (16 preceding siblings ...)
2024-09-18 21:07 ` [PULL 17/18] plugins: add option to dump write argument to syscall plugin Alex Bennée
@ 2024-09-18 21:07 ` Alex Bennée
2024-09-19 9:50 ` [PULL 00/18] tcg plugins (deprecations, mem apis, contrib plugins) Peter Maydell
18 siblings, 0 replies; 23+ messages in thread
From: Alex Bennée @ 2024-09-18 21:07 UTC (permalink / raw)
To: qemu-devel
Cc: Alex Bennée, Elisha Hollander, Richard Henderson,
Pierrick Bouvier, Alexandre Iooss, Mahmoud Mandour
Although we asks for instructions per second we work in quanta and
that cannot be 0. Fail to load the plugin instead and report the
minimum IPS we can handle.
Reported-by: Elisha Hollander <just4now666666@gmail.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Message-Id: <20240916085400.1046925-19-alex.bennee@linaro.org>
diff --git a/contrib/plugins/ips.c b/contrib/plugins/ips.c
index 29fa556d0f..e5297dbb01 100644
--- a/contrib/plugins/ips.c
+++ b/contrib/plugins/ips.c
@@ -152,6 +152,12 @@ QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plugin_id_t id,
vcpus = qemu_plugin_scoreboard_new(sizeof(vCPUTime));
max_insn_per_quantum = max_insn_per_second / NUM_TIME_UPDATE_PER_SEC;
+ if (max_insn_per_quantum == 0) {
+ fprintf(stderr, "minimum of %d instructions per second needed\n",
+ NUM_TIME_UPDATE_PER_SEC);
+ return -1;
+ }
+
time_handle = qemu_plugin_request_time_control();
g_assert(time_handle);
--
2.39.5
^ permalink raw reply related [flat|nested] 23+ messages in thread* Re: [PULL 00/18] tcg plugins (deprecations, mem apis, contrib plugins)
2024-09-18 21:06 [PULL 00/18] tcg plugins (deprecations, mem apis, contrib plugins) Alex Bennée
` (17 preceding siblings ...)
2024-09-18 21:07 ` [PULL 18/18] contrib/plugins: avoid hanging program Alex Bennée
@ 2024-09-19 9:50 ` Peter Maydell
2024-09-19 13:11 ` Alex Bennée
18 siblings, 1 reply; 23+ messages in thread
From: Peter Maydell @ 2024-09-19 9:50 UTC (permalink / raw)
To: Alex Bennée; +Cc: qemu-devel
On Wed, 18 Sept 2024 at 22:08, Alex Bennée <alex.bennee@linaro.org> wrote:
>
> The following changes since commit 2b81c046252fbfb375ad30632362fc16e6e22bd5:
>
> Merge tag 'block-pull-request' of https://gitlab.com/stefanha/qemu into staging (2024-09-17 14:02:18 +0100)
>
> are available in the Git repository at:
>
> https://gitlab.com/stsquad/qemu.git tags/pull-tcg-plugin-memory-180924-2
>
> for you to fetch changes up to a33f4871e0a0f4bf1cb037ab29fae7df7f2fc658:
>
> contrib/plugins: avoid hanging program (2024-09-18 21:02:36 +0100)
>
> ----------------------------------------------------------------
> TCG plugin memory instrumentation updates
>
> - deprecate plugins on 32 bit hosts
> - deprecate plugins with TCI
> - extend memory API to save value
> - add check-tcg tests to exercise new memory API
> - fix timer deadlock with non-changing timer
> - add basic block vector plugin to contrib
> - add cflow plugin to contrib
> - extend syscall plugin to dump write memory
> - validate ips plugin arguments meet minimum slice value
>
> ----------------------------------------------------------------
Fails to build on macos:
https://gitlab.com/qemu-project/qemu/-/jobs/7865151156
../tests/tcg/plugins/mem.c:12:10: fatal error: 'endian.h' file not found
endian.h is a Linuxism.
While I'm looking at the code, this caught my eye:
case QEMU_PLUGIN_MEM_VALUE_U64:
{
uint64_t *p = (uint64_t *) &ri->data[offset];
uint64_t val = be ? htobe64(value.data.u64) : htole64(value.data.u64);
if (is_store) {
*p = val;
} else if (*p != val) {
unseen_data = true;
}
break;
}
Casting a random byte pointer to uint64_t* like that
and dereferencing it isn't valid -- it can fault if
it's not aligned correctly.
I suspect the plugin needs to define versions of at least some
of the functionality in qemu's include/qemu/bswap.h.
thanks
-- PMM
^ permalink raw reply [flat|nested] 23+ messages in thread* Re: [PULL 00/18] tcg plugins (deprecations, mem apis, contrib plugins)
2024-09-19 9:50 ` [PULL 00/18] tcg plugins (deprecations, mem apis, contrib plugins) Peter Maydell
@ 2024-09-19 13:11 ` Alex Bennée
2024-09-19 13:14 ` Peter Maydell
0 siblings, 1 reply; 23+ messages in thread
From: Alex Bennée @ 2024-09-19 13:11 UTC (permalink / raw)
To: Peter Maydell; +Cc: qemu-devel
Peter Maydell <peter.maydell@linaro.org> writes:
> On Wed, 18 Sept 2024 at 22:08, Alex Bennée <alex.bennee@linaro.org> wrote:
>>
>> The following changes since commit 2b81c046252fbfb375ad30632362fc16e6e22bd5:
>>
>> Merge tag 'block-pull-request' of https://gitlab.com/stefanha/qemu into staging (2024-09-17 14:02:18 +0100)
>>
>> are available in the Git repository at:
>>
>> https://gitlab.com/stsquad/qemu.git tags/pull-tcg-plugin-memory-180924-2
>>
>> for you to fetch changes up to a33f4871e0a0f4bf1cb037ab29fae7df7f2fc658:
>>
>> contrib/plugins: avoid hanging program (2024-09-18 21:02:36 +0100)
>>
>> ----------------------------------------------------------------
>> TCG plugin memory instrumentation updates
>>
>> - deprecate plugins on 32 bit hosts
>> - deprecate plugins with TCI
>> - extend memory API to save value
>> - add check-tcg tests to exercise new memory API
>> - fix timer deadlock with non-changing timer
>> - add basic block vector plugin to contrib
>> - add cflow plugin to contrib
>> - extend syscall plugin to dump write memory
>> - validate ips plugin arguments meet minimum slice value
>>
>> ----------------------------------------------------------------
>
> Fails to build on macos:
> https://gitlab.com/qemu-project/qemu/-/jobs/7865151156
>
> ../tests/tcg/plugins/mem.c:12:10: fatal error: 'endian.h' file not found
>
> endian.h is a Linuxism.
Doh - I'd written it off the failure as waiting for the MacOS bump and
didn't see the actual error. I'll see what we can do.
>
> While I'm looking at the code, this caught my eye:
>
> case QEMU_PLUGIN_MEM_VALUE_U64:
> {
> uint64_t *p = (uint64_t *) &ri->data[offset];
> uint64_t val = be ? htobe64(value.data.u64) : htole64(value.data.u64);
> if (is_store) {
> *p = val;
> } else if (*p != val) {
> unseen_data = true;
> }
> break;
> }
>
> Casting a random byte pointer to uint64_t* like that
> and dereferencing it isn't valid -- it can fault if
> it's not aligned correctly.
Hmm in the normal case of x86 hosts we will never hit this. I guess we
could do a memcpy step and then the byteswap?
> I suspect the plugin needs to define versions of at least some
> of the functionality in qemu's include/qemu/bswap.h.
Could it be included directly without bringing in the rest of QEMU's
include deps?
>
> thanks
> -- PMM
--
Alex Bennée
Virtualisation Tech Lead @ Linaro
^ permalink raw reply [flat|nested] 23+ messages in thread* Re: [PULL 00/18] tcg plugins (deprecations, mem apis, contrib plugins)
2024-09-19 13:11 ` Alex Bennée
@ 2024-09-19 13:14 ` Peter Maydell
2024-09-19 14:33 ` Alex Bennée
0 siblings, 1 reply; 23+ messages in thread
From: Peter Maydell @ 2024-09-19 13:14 UTC (permalink / raw)
To: Alex Bennée; +Cc: qemu-devel
On Thu, 19 Sept 2024 at 14:11, Alex Bennée <alex.bennee@linaro.org> wrote:
>
> Peter Maydell <peter.maydell@linaro.org> writes:
> > While I'm looking at the code, this caught my eye:
> >
> > case QEMU_PLUGIN_MEM_VALUE_U64:
> > {
> > uint64_t *p = (uint64_t *) &ri->data[offset];
> > uint64_t val = be ? htobe64(value.data.u64) : htole64(value.data.u64);
> > if (is_store) {
> > *p = val;
> > } else if (*p != val) {
> > unseen_data = true;
> > }
> > break;
> > }
> >
> > Casting a random byte pointer to uint64_t* like that
> > and dereferencing it isn't valid -- it can fault if
> > it's not aligned correctly.
>
> Hmm in the normal case of x86 hosts we will never hit this.
Not necessarily -- some x86 SIMD insns enforce alignment.
> I guess we
> could do a memcpy step and then the byteswap?
That's what bswap.h does, yes.
> Could it be included directly without bringing in the rest of QEMU's
> include deps?
It's technically quite close to standalone I think,
but I think it would be a bad idea to directly include
it because once you put QEMU's include/ on the plugin
compile include path then that's a slippery slope to
the plugins not actually being standalone code any more.
-- PMM
^ permalink raw reply [flat|nested] 23+ messages in thread* Re: [PULL 00/18] tcg plugins (deprecations, mem apis, contrib plugins)
2024-09-19 13:14 ` Peter Maydell
@ 2024-09-19 14:33 ` Alex Bennée
0 siblings, 0 replies; 23+ messages in thread
From: Alex Bennée @ 2024-09-19 14:33 UTC (permalink / raw)
To: Peter Maydell; +Cc: qemu-devel
Peter Maydell <peter.maydell@linaro.org> writes:
> On Thu, 19 Sept 2024 at 14:11, Alex Bennée <alex.bennee@linaro.org> wrote:
>>
>> Peter Maydell <peter.maydell@linaro.org> writes:
>> > While I'm looking at the code, this caught my eye:
>> >
>> > case QEMU_PLUGIN_MEM_VALUE_U64:
>> > {
>> > uint64_t *p = (uint64_t *) &ri->data[offset];
>> > uint64_t val = be ? htobe64(value.data.u64) : htole64(value.data.u64);
>> > if (is_store) {
>> > *p = val;
>> > } else if (*p != val) {
>> > unseen_data = true;
>> > }
>> > break;
>> > }
>> >
>> > Casting a random byte pointer to uint64_t* like that
>> > and dereferencing it isn't valid -- it can fault if
>> > it's not aligned correctly.
>>
>> Hmm in the normal case of x86 hosts we will never hit this.
>
> Not necessarily -- some x86 SIMD insns enforce alignment.
>
>> I guess we
>> could do a memcpy step and then the byteswap?
>
> That's what bswap.h does, yes.
>
>> Could it be included directly without bringing in the rest of QEMU's
>> include deps?
>
> It's technically quite close to standalone I think,
> but I think it would be a bad idea to directly include
> it because once you put QEMU's include/ on the plugin
> compile include path then that's a slippery slope to
> the plugins not actually being standalone code any more.
In this case tests/tcg/plugins are built for testing the implementation.
We could let it slide to save on just copy and pasting the whole file:
--8<---------------cut here---------------start------------->8---
modified tests/tcg/plugins/mem.c
@@ -9,10 +9,23 @@
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
-#include <endian.h>
#include <stdio.h>
#include <glib.h>
+/*
+ * plugins should not include anything from QEMU aside from the
+ * API header. However the bswap.h header is sufficiently self
+ * contained that we include it here to avoid code duplication.
+ */
+#define HOST_BIG_ENDIAN (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
+#define HOST_LONG_BITS (__SIZEOF_POINTER__ * 8)
+#ifndef glue
+#define xglue(x, y) x ## y
+#define glue(x, y) xglue(x, y)
+#define stringify(s) tostring(s)
+#define tostring(s) #s
+#endif
+#include <bswap.h>
#include <qemu-plugin.h>
QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION;
@@ -154,33 +167,45 @@ static void update_region_info(uint64_t region, uint64_t offset,
case QEMU_PLUGIN_MEM_VALUE_U16:
{
uint16_t *p = (uint16_t *) &ri->data[offset];
- uint16_t val = be ? htobe16(value.data.u16) : htole16(value.data.u16);
if (is_store) {
- *p = val;
- } else if (*p != val) {
- unseen_data = true;
+ if (be) {
+ stw_be_p(p, value.data.u16);
+ } else {
+ stw_le_p(p, value.data.u16);
+ }
+ } else {
+ uint16_t val = be ? lduw_be_p(p) : lduw_le_p(p);
+ unseen_data = val != value.data.u16;
}
break;
}
case QEMU_PLUGIN_MEM_VALUE_U32:
{
uint32_t *p = (uint32_t *) &ri->data[offset];
- uint32_t val = be ? htobe32(value.data.u32) : htole32(value.data.u32);
if (is_store) {
- *p = val;
- } else if (*p != val) {
- unseen_data = true;
+ if (be) {
+ stl_be_p(p, value.data.u32);
+ } else {
+ stl_le_p(p, value.data.u32);
+ }
+ } else {
+ uint32_t val = be ? ldl_be_p(p) : ldl_le_p(p);
+ unseen_data = val != value.data.u32;
}
break;
}
case QEMU_PLUGIN_MEM_VALUE_U64:
{
uint64_t *p = (uint64_t *) &ri->data[offset];
- uint64_t val = be ? htobe64(value.data.u64) : htole64(value.data.u64);
if (is_store) {
- *p = val;
- } else if (*p != val) {
- unseen_data = true;
+ if (be) {
+ stq_be_p(p, value.data.u64);
+ } else {
+ stq_le_p(p, value.data.u64);
+ }
+ } else {
+ uint64_t val = be ? ldq_be_p(p) : ldq_le_p(p);
+ unseen_data = val != value.data.u64;
}
break;
--8<---------------cut here---------------end--------------->8---
--
Alex Bennée
Virtualisation Tech Lead @ Linaro
^ permalink raw reply [flat|nested] 23+ messages in thread