diff --git a/MAINTAINERS b/MAINTAINERS index c340bb02b0..83b55030ad 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -3017,6 +3017,7 @@ F: include/tcg/ TCG Plugins M: Alex Bennée +R: Alexandre Iooss S: Maintained F: docs/devel/tcg-plugins.rst F: plugins/ diff --git a/contrib/plugins/Makefile b/contrib/plugins/Makefile index 3431bc1ce9..3c9209b6b0 100644 --- a/contrib/plugins/Makefile +++ b/contrib/plugins/Makefile @@ -13,6 +13,7 @@ include $(BUILD_DIR)/config-host.mak VPATH += $(SRC_PATH)/contrib/plugins NAMES := +NAMES += execlog NAMES += hotblocks NAMES += hotpages NAMES += howvec diff --git a/contrib/plugins/execlog.c b/contrib/plugins/execlog.c new file mode 100644 index 0000000000..2de9f0d7d4 --- /dev/null +++ b/contrib/plugins/execlog.c @@ -0,0 +1,153 @@ +/* + * Copyright (C) 2021, Alexandre Iooss + * + * Log instruction execution with memory access. + * + * License: GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ +#include +#include +#include +#include +#include +#include + +#include + +QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION; + +/* Store last executed instruction on each vCPU as a GString */ +GArray *last_exec; + +/** + * Add memory read or write information to current instruction log + */ +static void vcpu_mem(unsigned int cpu_index, qemu_plugin_meminfo_t info, + uint64_t vaddr, void *udata) +{ + GString *s; + + /* Find vCPU in array */ + g_assert(cpu_index < last_exec->len); + s = g_array_index(last_exec, GString *, cpu_index); + + /* Indicate type of memory access */ + if (qemu_plugin_mem_is_store(info)) { + g_string_append(s, ", store"); + } else { + g_string_append(s, ", load"); + } + + /* If full system emulation log physical address and device name */ + struct qemu_plugin_hwaddr *hwaddr = qemu_plugin_get_hwaddr(info, vaddr); + if (hwaddr) { + uint64_t addr = qemu_plugin_hwaddr_phys_addr(hwaddr); + const char *name = qemu_plugin_hwaddr_device_name(hwaddr); + g_string_append_printf(s, ", 0x%08"PRIx64", %s", addr, name); + } else { + g_string_append_printf(s, ", 0x%08"PRIx64, vaddr); + } +} + +/** + * Log instruction execution + */ +static void vcpu_insn_exec(unsigned int cpu_index, void *udata) +{ + GString *s; + + /* Find or create vCPU in array */ + while (cpu_index >= last_exec->len) { + s = g_string_new(NULL); + g_array_append_val(last_exec, s); + } + s = g_array_index(last_exec, GString *, cpu_index); + + /* Print previous instruction in cache */ + if (s->len) { + qemu_plugin_outs(s->str); + qemu_plugin_outs("s\n"); + } + + /* Store new instruction in cache */ + /* vcpu_mem will add memory access information to last_exec */ + g_string_printf(s, "%u, ", cpu_index); + g_string_append(s, (char *)udata); +} + +/** + * On translation block new translation + * + * QEMU convert code by translation block (TB). By hooking here we can then hook + * a callback on each instruction and memory access. + */ +static void vcpu_tb_trans(qemu_plugin_id_t id, struct qemu_plugin_tb *tb) +{ + struct qemu_plugin_insn *insn; + uint64_t insn_vaddr; + uint32_t insn_opcode; + char *insn_disas; + + size_t n = qemu_plugin_tb_n_insns(tb); + for (size_t i = 0; i < n; i++) { + /* + * `insn` is shared between translations in QEMU, copy needed data here. + * `output` is never freed as it might be used multiple times during + * the emulation lifetime. + * We only consider the first 32 bits of the instruction, this may be + * a limitation for CISC architectures. + */ + insn = qemu_plugin_tb_get_insn(tb, i); + insn_vaddr = qemu_plugin_insn_vaddr(insn); + insn_opcode = *((uint32_t *)qemu_plugin_insn_data(insn)); + insn_disas = qemu_plugin_insn_disas(insn); + char *output = g_strdup_printf("0x%"PRIx64", 0x%"PRIx32", \"%s\"", + insn_vaddr, insn_opcode, insn_disas); + + /* Register callback on memory read or write */ + qemu_plugin_register_vcpu_mem_cb(insn, vcpu_mem, + QEMU_PLUGIN_CB_NO_REGS, + QEMU_PLUGIN_MEM_RW, NULL); + + /* Register callback on instruction */ + qemu_plugin_register_vcpu_insn_exec_cb(insn, vcpu_insn_exec, + QEMU_PLUGIN_CB_NO_REGS, output); + } +} + +/** + * On plugin exit, print last instruction in cache + */ +static void plugin_exit(qemu_plugin_id_t id, void *p) +{ + guint i; + GString *s; + for (i = 0; i < last_exec->len; i++) { + s = g_array_index(last_exec, GString *, i); + if (s->str) { + qemu_plugin_outs(s->str); + qemu_plugin_outs("\n"); + } + } +} + +/** + * Install the plugin + */ +QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plugin_id_t id, + const qemu_info_t *info, int argc, + char **argv) +{ + /* + * Initialize dynamic array to cache vCPU instruction. In user mode + * we don't know the size before emulation. + */ + last_exec = g_array_new(FALSE, FALSE, sizeof(GString *)); + + /* Register translation block and exit callbacks */ + qemu_plugin_register_vcpu_tb_trans_cb(id, vcpu_tb_trans); + qemu_plugin_register_atexit_cb(id, plugin_exit, NULL); + + return 0; +}