| /* |
| * Copyright (C) 2025, Pierrick Bouvier <pierrick.bouvier@linaro.org> |
| * |
| * Generates a trace compatible with uftrace (similar to uftrace record). |
| * https://github.com/namhyung/uftrace |
| * |
| * See docs/about/emulation.rst|Uftrace for details and examples. |
| * |
| * SPDX-License-Identifier: GPL-2.0-or-later |
| */ |
| |
| #include <qemu-plugin.h> |
| #include <glib.h> |
| #include <stdio.h> |
| #include <sys/stat.h> |
| #include <sys/time.h> |
| #include <time.h> |
| #include <unistd.h> |
| |
| #define MiB (INT64_C(1) << 20) |
| #define NANOSECONDS_PER_SECOND 1000000000LL |
| #define TRACE_FLUSH_SIZE (32 * MiB) |
| #define TRACE_ID_SCALE 100 |
| |
| QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION; |
| |
| typedef struct { |
| GArray *s; |
| } Callstack; |
| |
| typedef struct { |
| uint64_t pc; |
| uint64_t frame_pointer; |
| } CallstackEntry; |
| |
| typedef struct { |
| GArray *t; |
| GString *path; |
| GString *name; |
| uint32_t id; |
| } Trace; |
| |
| typedef struct Cpu Cpu; |
| |
| typedef struct { |
| void (*init)(Cpu *cpu); |
| void (*end)(Cpu *cpu); |
| uint64_t (*get_frame_pointer)(Cpu *cpu); |
| uint8_t (*get_privilege_level)(Cpu *cpu); |
| uint8_t (*num_privilege_levels)(void); |
| const char *(*get_privilege_level_name)(uint8_t pl); |
| bool (*does_insn_modify_frame_pointer)(const char *disas); |
| } CpuOps; |
| |
| typedef struct Cpu { |
| Trace *trace; |
| Callstack *cs; |
| uint8_t privilege_level; |
| GArray *traces; /* Trace *traces [] */ |
| GByteArray *buf; |
| CpuOps ops; |
| void *arch; |
| } Cpu; |
| |
| typedef enum { |
| AARCH64_EL0_SECURE, |
| AARCH64_EL0_NONSECURE, |
| AARCH64_EL0_REALM, |
| AARCH64_EL1_SECURE, |
| AARCH64_EL1_NONSECURE, |
| AARCH64_EL1_REALM, |
| AARCH64_EL2_SECURE, |
| AARCH64_EL2_NONSECURE, |
| AARCH64_EL2_REALM, |
| AARCH64_EL3, |
| AARCH64_PRIVILEGE_LEVEL_MAX, |
| } Aarch64PrivilegeLevel; |
| |
| typedef struct { |
| struct qemu_plugin_register *reg_fp; |
| struct qemu_plugin_register *reg_cpsr; |
| struct qemu_plugin_register *reg_scr_el3; |
| } Aarch64Cpu; |
| |
| typedef enum { |
| X64_RING0, |
| X64_RING1, |
| X64_RING2, |
| X64_RING3, |
| X64_REAL_MODE, |
| X64_PRIVILEGE_LEVEL_MAX, |
| } X64PrivilegeLevel; |
| |
| typedef struct { |
| struct qemu_plugin_register *reg_rbp; |
| struct qemu_plugin_register *reg_cs; |
| struct qemu_plugin_register *reg_cr0; |
| } X64Cpu; |
| |
| typedef struct { |
| uint64_t timestamp; |
| uint64_t data; |
| } UftraceEntry; |
| |
| typedef enum { |
| UFTRACE_ENTRY, |
| UFTRACE_EXIT, |
| UFTRACE_LOST, |
| UFTRACE_EVENT, |
| } UftraceRecordType; |
| |
| static struct qemu_plugin_scoreboard *score; |
| static bool trace_privilege_level; |
| static CpuOps arch_ops; |
| |
| static uint64_t gettime_ns(void) |
| { |
| #ifdef _WIN32 |
| /* |
| * On Windows, timespec_get is available only with UCRT, but not with |
| * MinGW64 environment. Simplify by using only gettimeofday on this |
| * platform. This may result in a precision loss. |
| */ |
| struct timeval tv; |
| gettimeofday(&tv, NULL); |
| uint64_t now_ns = tv.tv_sec * NANOSECONDS_PER_SECOND + tv.tv_usec * 1000; |
| #else |
| /* We need nanosecond precision for short lived functions. */ |
| struct timespec ts; |
| timespec_get(&ts, TIME_UTC); |
| uint64_t now_ns = ts.tv_sec * NANOSECONDS_PER_SECOND + ts.tv_nsec; |
| #endif |
| return now_ns; |
| } |
| |
| static void uftrace_write_map(bool system_emulation) |
| { |
| const char *path = "./uftrace.data/sid-0.map"; |
| |
| if (system_emulation && access(path, F_OK) == 0) { |
| /* do not erase existing map in system emulation, as a custom one might |
| * already have been generated by uftrace_symbols.py */ |
| return; |
| } |
| |
| FILE *sid_map = fopen(path, "w"); |
| g_assert(sid_map); |
| |
| if (system_emulation) { |
| fprintf(sid_map, |
| "# map stack on highest address possible, to prevent uftrace\n" |
| "# from considering any kernel address\n"); |
| fprintf(sid_map, |
| "ffffffffffff-ffffffffffff rw-p 00000000 00:00 0 [stack]\n"); |
| } else { |
| /* in user mode, copy /proc/self/maps instead */ |
| FILE *self_map = fopen("/proc/self/maps", "r"); |
| g_assert(self_map); |
| for (;;) { |
| int c = fgetc(self_map); |
| if (c == EOF) { |
| break; |
| } |
| fputc(c, sid_map); |
| } |
| fclose(self_map); |
| } |
| fclose(sid_map); |
| } |
| |
| static void uftrace_write_task(const GArray *traces) |
| { |
| FILE *task = fopen("./uftrace.data/task.txt", "w"); |
| g_assert(task); |
| for (int i = 0; i < traces->len; ++i) { |
| Trace *t = g_array_index(traces, Trace*, i); |
| fprintf(task, "SESS timestamp=0.0 pid=%"PRIu32" sid=0 exename=\"%s\"\n", |
| t->id, t->name->str); |
| fprintf(task, "TASK timestamp=0.0 tid=%"PRIu32" pid=%"PRIu32"\n", |
| t->id, t->id); |
| } |
| fclose(task); |
| } |
| |
| static void uftrace_write_info(const GArray *traces) |
| { |
| g_autoptr(GString) taskinfo_tids = g_string_new("taskinfo:tids="); |
| for (int i = 0; i < traces->len; ++i) { |
| Trace *t = g_array_index(traces, Trace*, i); |
| const char *delim = i > 0 ? "," : ""; |
| g_string_append_printf(taskinfo_tids, "%s%"PRIu32, delim, t->id); |
| } |
| |
| g_autoptr(GString) taskinfo_nr_tid = g_string_new("taskinfo:nr_tid="); |
| g_string_append_printf(taskinfo_nr_tid, "%d", traces->len); |
| |
| FILE *info = fopen("./uftrace.data/info", "w"); |
| g_assert(info); |
| /* |
| * $ uftrace dump --debug |
| * uftrace file header: magic = 4674726163652100 |
| * uftrace file header: version = 4 |
| * uftrace file header: header size = 40 |
| * uftrace file header: endian = 1 (little) |
| * uftrace file header: class = 2 (64 bit) |
| * uftrace file header: features = 0x1263 (PLTHOOK | ... |
| * uftrace file header: info = 0x7bff (EXE_NAME | ... |
| * <0000000000000000>: 46 74 72 61 63 65 21 00 04 00 00 00 28 00 01 02 |
| * <0000000000000010>: 63 12 00 00 00 00 00 00 ff 7b 00 00 00 00 00 00 |
| * <0000000000000020>: 00 04 00 00 00 00 00 00 |
| */ |
| const uint8_t header[] = {0x46, 0x74, 0x72, 0x61, 0x63, 0x65, 0x21, 0x00, |
| 0x04, 0x00, 0x00, 0x00, 0x28, 0x00, 0x01, 0x02, |
| 0x63, 0x12, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, |
| 0xff, 0x7b, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, |
| 0x00, 0x04, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}; |
| size_t wrote = fwrite(header, sizeof(header), 1, info); |
| g_assert(wrote == 1); |
| const char *info_data[] = { |
| "exename:", |
| "build_id:0000000000000000000000000000000000000000", |
| "exit_status:", |
| "cmdline:", |
| "cpuinfo:lines=2", |
| "cpuinfo:nr_cpus=", |
| "cpuinfo:desc=", |
| "meminfo:", |
| "osinfo:lines=3", |
| "osinfo:kernel=", |
| "osinfo:hostname=", |
| "osinfo:distro=", |
| "taskinfo:lines=2", |
| taskinfo_nr_tid->str, |
| taskinfo_tids->str, |
| "usageinfo:lines=6", |
| "usageinfo:systime=", |
| "usageinfo:usrtime=", |
| "usageinfo:ctxsw=", |
| "usageinfo:maxrss=", |
| "usageinfo:pagefault=", |
| "usageinfo:iops=", |
| "loadinfo:", |
| "record_date:", |
| "elapsed_time:", |
| "pattern_type:regex", |
| "uftrace_version:", |
| "utc_offset:", |
| 0}; |
| const char **info_data_it = info_data; |
| while (*(info_data_it)) { |
| fprintf(info, "%s\n", *info_data_it); |
| ++info_data_it; |
| } |
| fclose(info); |
| } |
| |
| static Callstack *callstack_new(void) |
| { |
| Callstack *cs = g_new0(Callstack, 1); |
| cs->s = g_array_new(false, false, sizeof(CallstackEntry)); |
| return cs; |
| } |
| |
| static void callstack_free(Callstack *cs) |
| { |
| g_array_free(cs->s, true); |
| cs->s = NULL; |
| g_free(cs); |
| } |
| |
| static size_t callstack_depth(const Callstack *cs) |
| { |
| return cs->s->len; |
| } |
| |
| static size_t callstack_empty(const Callstack *cs) |
| { |
| return callstack_depth(cs) == 0; |
| } |
| |
| static void callstack_clear(Callstack *cs) |
| { |
| g_array_set_size(cs->s, 0); |
| } |
| |
| static const CallstackEntry *callstack_at(const Callstack *cs, size_t depth) |
| { |
| g_assert(depth > 0); |
| g_assert(depth <= callstack_depth(cs)); |
| return &g_array_index(cs->s, CallstackEntry, depth - 1); |
| } |
| |
| static CallstackEntry callstack_top(const Callstack *cs) |
| { |
| if (callstack_depth(cs) >= 1) { |
| return *callstack_at(cs, callstack_depth(cs)); |
| } |
| return (CallstackEntry){}; |
| } |
| |
| static CallstackEntry callstack_caller(const Callstack *cs) |
| { |
| if (callstack_depth(cs) >= 2) { |
| return *callstack_at(cs, callstack_depth(cs) - 1); |
| } |
| return (CallstackEntry){}; |
| } |
| |
| static void callstack_push(Callstack *cs, CallstackEntry e) |
| { |
| g_array_append_val(cs->s, e); |
| } |
| |
| static CallstackEntry callstack_pop(Callstack *cs) |
| { |
| g_assert(!callstack_empty(cs)); |
| CallstackEntry e = callstack_top(cs); |
| g_array_set_size(cs->s, callstack_depth(cs) - 1); |
| return e; |
| } |
| |
| static Trace *trace_new(uint32_t id, GString *name) |
| { |
| Trace *t = g_new0(Trace, 1); |
| t->t = g_array_new(false, false, sizeof(UftraceEntry)); |
| t->path = g_string_new(NULL); |
| g_string_append_printf(t->path, "./uftrace.data/%"PRIu32".dat", id); |
| t->name = g_string_new(name->str); |
| t->id = id; |
| return t; |
| } |
| |
| static void trace_free(Trace *t) |
| { |
| g_assert(t->t->len == 0); |
| g_array_free(t->t, true); |
| t->t = NULL; |
| g_string_free(t->path, true); |
| t->path = NULL; |
| g_string_free(t->name, true); |
| t->name = NULL; |
| g_free(t); |
| } |
| |
| static void trace_flush(Trace *t, bool append) |
| { |
| int create_dir = g_mkdir_with_parents("./uftrace.data", |
| S_IRWXU | S_IRWXG | S_IRWXO); |
| g_assert(create_dir == 0); |
| FILE *dat = fopen(t->path->str, append ? "a" : "w"); |
| g_assert(dat); |
| GArray *data = t->t; |
| if (data->len) { |
| size_t wrote = fwrite(data->data, sizeof(UftraceEntry), data->len, dat); |
| g_assert(wrote == data->len); |
| } |
| fclose(dat); |
| g_array_set_size(data, 0); |
| } |
| |
| static void trace_add_entry(Trace *t, uint64_t timestamp, uint64_t pc, |
| size_t depth, UftraceRecordType type) |
| { |
| /* https://github.com/namhyung/uftrace/blob/v0.18/libmcount/record.c#L909 */ |
| const uint64_t record_magic = 0x5; |
| uint64_t data = type | (record_magic << 3); |
| data += depth << 6; |
| data += pc << 16; |
| UftraceEntry e = {.timestamp = timestamp, .data = data}; |
| g_array_append_val(t->t, e); |
| if (t->t->len * sizeof(UftraceEntry) > TRACE_FLUSH_SIZE) { |
| trace_flush(t, true); |
| } |
| } |
| |
| static void trace_enter_function(Trace *t, uint64_t timestamp, |
| uint64_t pc, size_t depth) |
| { |
| trace_add_entry(t, timestamp, pc, depth, UFTRACE_ENTRY); |
| } |
| |
| static void trace_exit_function(Trace *t, uint64_t timestamp, |
| uint64_t pc, size_t depth) |
| { |
| trace_add_entry(t, timestamp, pc, depth, UFTRACE_EXIT); |
| } |
| |
| static void trace_enter_stack(Trace *t, Callstack *cs, uint64_t timestamp) |
| { |
| for (size_t depth = 1; depth <= callstack_depth(cs); ++depth) { |
| trace_enter_function(t, timestamp, callstack_at(cs, depth)->pc, depth); |
| } |
| } |
| |
| static void trace_exit_stack(Trace *t, Callstack *cs, uint64_t timestamp) |
| { |
| for (size_t depth = callstack_depth(cs); depth > 0; --depth) { |
| trace_exit_function(t, timestamp, callstack_at(cs, depth)->pc, depth); |
| } |
| } |
| |
| static uint64_t cpu_read_register64(Cpu *cpu, struct qemu_plugin_register *reg) |
| { |
| GByteArray *buf = cpu->buf; |
| g_byte_array_set_size(buf, 0); |
| size_t sz = qemu_plugin_read_register(reg, buf); |
| g_assert(sz == 8); |
| g_assert(buf->len == 8); |
| return *((uint64_t *) buf->data); |
| } |
| |
| static uint32_t cpu_read_register32(Cpu *cpu, struct qemu_plugin_register *reg) |
| { |
| GByteArray *buf = cpu->buf; |
| g_byte_array_set_size(buf, 0); |
| size_t sz = qemu_plugin_read_register(reg, buf); |
| g_assert(sz == 4); |
| g_assert(buf->len == 4); |
| return *((uint32_t *) buf->data); |
| } |
| |
| static uint64_t cpu_read_memory64(Cpu *cpu, uint64_t addr) |
| { |
| g_assert(addr); |
| GByteArray *buf = cpu->buf; |
| g_byte_array_set_size(buf, 0); |
| bool read = qemu_plugin_read_memory_vaddr(addr, buf, 8); |
| if (!read) { |
| return 0; |
| } |
| g_assert(buf->len == 8); |
| return *((uint64_t *) buf->data); |
| } |
| |
| static void cpu_unwind_stack(Cpu *cpu, uint64_t frame_pointer, uint64_t pc) |
| { |
| g_assert(callstack_empty(cpu->cs)); |
| |
| #define UNWIND_STACK_MAX_DEPTH 1024 |
| CallstackEntry unwind[UNWIND_STACK_MAX_DEPTH]; |
| size_t depth = 0; |
| do { |
| /* check we don't have an infinite stack */ |
| for (size_t i = 0; i < depth; ++i) { |
| if (frame_pointer == unwind[i].frame_pointer) { |
| break; |
| } |
| } |
| CallstackEntry e = {.frame_pointer = frame_pointer, .pc = pc}; |
| unwind[depth] = e; |
| depth++; |
| if (frame_pointer) { |
| frame_pointer = cpu_read_memory64(cpu, frame_pointer); |
| } |
| pc = cpu_read_memory64(cpu, frame_pointer + 8); /* read previous lr */ |
| } while (frame_pointer && pc && depth < UNWIND_STACK_MAX_DEPTH); |
| #undef UNWIND_STACK_MAX_DEPTH |
| |
| /* push it from bottom to top */ |
| while (depth) { |
| callstack_push(cpu->cs, unwind[depth - 1]); |
| --depth; |
| } |
| } |
| |
| static struct qemu_plugin_register *plugin_find_register(const char *name) |
| { |
| g_autoptr(GArray) regs = qemu_plugin_get_registers(); |
| for (int i = 0; i < regs->len; ++i) { |
| qemu_plugin_reg_descriptor *reg; |
| reg = &g_array_index(regs, qemu_plugin_reg_descriptor, i); |
| if (!strcmp(reg->name, name)) { |
| return reg->handle; |
| } |
| } |
| return NULL; |
| } |
| |
| static uint8_t aarch64_num_privilege_levels(void) |
| { |
| return AARCH64_PRIVILEGE_LEVEL_MAX; |
| } |
| |
| static const char *aarch64_get_privilege_level_name(uint8_t pl) |
| { |
| switch (pl) { |
| case AARCH64_EL0_SECURE: return "S-EL0"; |
| case AARCH64_EL0_NONSECURE: return "NS-EL0"; |
| case AARCH64_EL0_REALM: return "R-EL0"; |
| case AARCH64_EL1_SECURE: return "S-EL1"; |
| case AARCH64_EL1_NONSECURE: return "NS-EL1"; |
| case AARCH64_EL1_REALM: return "R-EL1"; |
| case AARCH64_EL2_SECURE: return "S-EL2"; |
| case AARCH64_EL2_NONSECURE: return "NS-EL2"; |
| case AARCH64_EL2_REALM: return "R-EL2"; |
| case AARCH64_EL3: return "EL3"; |
| default: |
| g_assert_not_reached(); |
| } |
| } |
| |
| static uint8_t aarch64_get_privilege_level(Cpu *cpu_) |
| { |
| Aarch64Cpu *cpu = cpu_->arch; |
| /* |
| * QEMU gdbstub does not provide access to CurrentEL, |
| * so we use CPSR instead. |
| */ |
| uint8_t el = cpu_read_register32(cpu_, cpu->reg_cpsr) >> 2 & 0b11; |
| |
| if (el == 3) { |
| return AARCH64_EL3; |
| } |
| |
| uint8_t ss = AARCH64_EL0_SECURE; |
| if (!cpu->reg_scr_el3) { |
| ss = AARCH64_EL0_NONSECURE; |
| } |
| uint64_t scr_el3 = cpu_read_register64(cpu_, cpu->reg_scr_el3); |
| uint64_t ns = (scr_el3 >> 0) & 0b1; |
| uint64_t nse = (scr_el3 >> 62) & 0b1; |
| switch (nse << 1 | ns) { |
| case 0b00: |
| ss = AARCH64_EL0_SECURE; |
| break; |
| case 0b01: |
| ss = AARCH64_EL0_NONSECURE; |
| break; |
| case 0b11: |
| ss = AARCH64_EL0_REALM; |
| break; |
| default: |
| g_assert_not_reached(); |
| } |
| |
| const uint8_t num_ss = 3; |
| Aarch64PrivilegeLevel pl = el * num_ss + ss; |
| return pl; |
| } |
| |
| static uint64_t aarch64_get_frame_pointer(Cpu *cpu_) |
| { |
| Aarch64Cpu *cpu = cpu_->arch; |
| return cpu_read_register64(cpu_, cpu->reg_fp); |
| } |
| |
| static void aarch64_init(Cpu *cpu_) |
| { |
| Aarch64Cpu *cpu = g_new0(Aarch64Cpu, 1); |
| cpu_->arch = cpu; |
| cpu->reg_fp = plugin_find_register("x29"); |
| if (!cpu->reg_fp) { |
| fprintf(stderr, "uftrace plugin: frame pointer register (x29) is not " |
| "available. Please use an AArch64 cpu (or -cpu max).\n"); |
| g_abort(); |
| } |
| cpu->reg_cpsr = plugin_find_register("cpsr"); |
| g_assert(cpu->reg_cpsr); |
| cpu->reg_scr_el3 = plugin_find_register("SCR_EL3"); |
| /* scr_el3 is optional */ |
| } |
| |
| static void aarch64_end(Cpu *cpu) |
| { |
| g_free(cpu->arch); |
| } |
| |
| static bool aarch64_does_insn_modify_frame_pointer(const char *disas) |
| { |
| /* |
| * Check if current instruction concerns fp register "x29". |
| * We add a prefix space to make sure we don't match addresses dump |
| * in disassembly. |
| */ |
| return strstr(disas, " x29"); |
| } |
| |
| static CpuOps aarch64_ops = { |
| .init = aarch64_init, |
| .end = aarch64_end, |
| .get_frame_pointer = aarch64_get_frame_pointer, |
| .get_privilege_level = aarch64_get_privilege_level, |
| .num_privilege_levels = aarch64_num_privilege_levels, |
| .get_privilege_level_name = aarch64_get_privilege_level_name, |
| .does_insn_modify_frame_pointer = aarch64_does_insn_modify_frame_pointer, |
| }; |
| |
| static uint8_t x64_num_privilege_levels(void) |
| { |
| return X64_PRIVILEGE_LEVEL_MAX; |
| } |
| |
| static const char *x64_get_privilege_level_name(uint8_t pl) |
| { |
| switch (pl) { |
| case X64_RING0: return "Ring0"; |
| case X64_RING1: return "Ring1"; |
| case X64_RING2: return "Ring2"; |
| case X64_RING3: return "Ring3"; |
| case X64_REAL_MODE: return "RealMode"; |
| default: |
| g_assert_not_reached(); |
| } |
| } |
| |
| static uint8_t x64_get_privilege_level(Cpu *cpu_) |
| { |
| X64Cpu *cpu = cpu_->arch; |
| uint64_t cr0 = cpu_read_register64(cpu_, cpu->reg_cr0); |
| uint64_t protected_mode = (cr0 >> 0) & 0b1; |
| if (!protected_mode) { |
| return X64_REAL_MODE; |
| } |
| uint32_t cs = cpu_read_register32(cpu_, cpu->reg_cs); |
| uint32_t ring_level = (cs >> 0) & 0b11; |
| return ring_level; |
| } |
| |
| static uint64_t x64_get_frame_pointer(Cpu *cpu_) |
| { |
| X64Cpu *cpu = cpu_->arch; |
| return cpu_read_register64(cpu_, cpu->reg_rbp); |
| } |
| |
| static void x64_init(Cpu *cpu_) |
| { |
| X64Cpu *cpu = g_new0(X64Cpu, 1); |
| cpu_->arch = cpu; |
| cpu->reg_rbp = plugin_find_register("rbp"); |
| g_assert(cpu->reg_rbp); |
| cpu->reg_cs = plugin_find_register("cs"); |
| g_assert(cpu->reg_cs); |
| cpu->reg_cr0 = plugin_find_register("cr0"); |
| g_assert(cpu->reg_cr0); |
| } |
| |
| static void x64_end(Cpu *cpu) |
| { |
| g_free(cpu->arch); |
| } |
| |
| static bool x64_does_insn_modify_frame_pointer(const char *disas) |
| { |
| return strstr(disas, "rbp"); |
| } |
| |
| static CpuOps x64_ops = { |
| .init = x64_init, |
| .end = x64_end, |
| .get_frame_pointer = x64_get_frame_pointer, |
| .get_privilege_level = x64_get_privilege_level, |
| .num_privilege_levels = x64_num_privilege_levels, |
| .get_privilege_level_name = x64_get_privilege_level_name, |
| .does_insn_modify_frame_pointer = x64_does_insn_modify_frame_pointer, |
| }; |
| |
| static void track_privilege_change(unsigned int cpu_index, void *udata) |
| { |
| Cpu *cpu = qemu_plugin_scoreboard_find(score, cpu_index); |
| uint8_t new_pl = cpu->ops.get_privilege_level(cpu); |
| |
| if (new_pl == cpu->privilege_level) { |
| return; |
| } |
| |
| uint64_t pc = (uintptr_t) udata; |
| uint64_t timestamp = gettime_ns(); |
| |
| trace_exit_stack(cpu->trace, cpu->cs, timestamp); |
| callstack_clear(cpu->cs); |
| |
| cpu->privilege_level = new_pl; |
| cpu->trace = g_array_index(cpu->traces, Trace*, new_pl); |
| |
| cpu_unwind_stack(cpu, cpu->ops.get_frame_pointer(cpu), pc); |
| trace_enter_stack(cpu->trace, cpu->cs, timestamp); |
| } |
| |
| static void track_callstack(unsigned int cpu_index, void *udata) |
| { |
| uint64_t pc = (uintptr_t) udata; |
| Cpu *cpu = qemu_plugin_scoreboard_find(score, cpu_index); |
| uint64_t timestamp = gettime_ns(); |
| Callstack *cs = cpu->cs; |
| Trace *t = cpu->trace; |
| |
| uint64_t fp = cpu->ops.get_frame_pointer(cpu); |
| if (!fp && callstack_empty(cs)) { |
| /* |
| * We simply push current pc. Note that we won't detect symbol change as |
| * long as a proper call does not happen. |
| */ |
| callstack_push(cs, (CallstackEntry){.frame_pointer = fp, .pc = pc}); |
| trace_enter_function(t, timestamp, pc, callstack_depth(cs)); |
| return; |
| } |
| |
| CallstackEntry top = callstack_top(cs); |
| if (fp == top.frame_pointer) { |
| /* same function */ |
| return; |
| } |
| |
| CallstackEntry caller = callstack_caller(cs); |
| if (fp == caller.frame_pointer) { |
| /* return */ |
| CallstackEntry e = callstack_pop(cs); |
| trace_exit_function(t, timestamp, e.pc, callstack_depth(cs)); |
| return; |
| } |
| |
| uint64_t caller_fp = fp ? cpu_read_memory64(cpu, fp) : 0; |
| if (caller_fp == top.frame_pointer) { |
| /* call */ |
| callstack_push(cs, (CallstackEntry){.frame_pointer = fp, .pc = pc}); |
| trace_enter_function(t, timestamp, pc, callstack_depth(cs)); |
| return; |
| } |
| |
| /* discontinuity, exit current stack and unwind new one */ |
| trace_exit_stack(t, cs, timestamp); |
| callstack_clear(cs); |
| |
| cpu_unwind_stack(cpu, fp, pc); |
| trace_enter_stack(t, cs, timestamp); |
| } |
| |
| static void vcpu_tb_trans(qemu_plugin_id_t id, struct qemu_plugin_tb *tb) |
| { |
| size_t n_insns = qemu_plugin_tb_n_insns(tb); |
| uintptr_t tb_pc = qemu_plugin_tb_vaddr(tb); |
| |
| if (trace_privilege_level) { |
| qemu_plugin_register_vcpu_tb_exec_cb(tb, track_privilege_change, |
| QEMU_PLUGIN_CB_R_REGS, |
| (void *) tb_pc); |
| } |
| |
| /* |
| * Callbacks and inline instrumentation are inserted before an instruction. |
| * Thus, to see instruction effect, we need to wait for next one. |
| * Potentially, the last instruction of a block could modify the frame |
| * pointer. Thus, we need to always instrument first instruction in a tb. |
| */ |
| bool instrument_insn = true; |
| for (size_t i = 0; i < n_insns; i++) { |
| struct qemu_plugin_insn *insn = qemu_plugin_tb_get_insn(tb, i); |
| |
| if (instrument_insn) { |
| uintptr_t pc = qemu_plugin_insn_vaddr(insn); |
| qemu_plugin_register_vcpu_insn_exec_cb(insn, track_callstack, |
| QEMU_PLUGIN_CB_R_REGS, |
| (void *) pc); |
| instrument_insn = false; |
| } |
| |
| char *disas = qemu_plugin_insn_disas(insn); |
| if (arch_ops.does_insn_modify_frame_pointer(disas)) { |
| instrument_insn = true; |
| } |
| } |
| } |
| |
| static void vcpu_init(qemu_plugin_id_t id, unsigned int vcpu_index) |
| { |
| Cpu *cpu = qemu_plugin_scoreboard_find(score, vcpu_index); |
| cpu->ops = arch_ops; |
| |
| cpu->ops.init(cpu); |
| cpu->buf = g_byte_array_new(); |
| cpu->traces = g_array_new(0, 0, sizeof(Trace *)); |
| |
| g_assert(vcpu_index < UINT32_MAX / TRACE_ID_SCALE); |
| g_assert(cpu->ops.num_privilege_levels() < TRACE_ID_SCALE); |
| /* trace_id is: cpu_number * TRACE_ID_SCALE + privilege_level */ |
| uint32_t trace_id = (vcpu_index + 1) * TRACE_ID_SCALE; |
| |
| if (trace_privilege_level) { |
| for (uint8_t pl = 0; pl < cpu->ops.num_privilege_levels(); ++pl) { |
| g_autoptr(GString) trace_name = g_string_new(NULL); |
| g_string_append_printf(trace_name, "cpu%u %s", vcpu_index, |
| cpu->ops.get_privilege_level_name(pl)); |
| Trace *t = trace_new(trace_id + pl, trace_name); |
| g_array_append_val(cpu->traces, t); |
| } |
| } else { |
| g_autoptr(GString) trace_name = g_string_new(NULL); |
| g_string_append_printf(trace_name, "cpu%u", vcpu_index); |
| Trace *t = trace_new(trace_id, trace_name); |
| g_array_append_val(cpu->traces, t); |
| } |
| |
| for (size_t i = 0; i < cpu->traces->len; ++i) { |
| /* create/truncate trace files */ |
| Trace *t = g_array_index(cpu->traces, Trace*, i); |
| trace_flush(t, false); |
| } |
| |
| cpu->cs = callstack_new(); |
| cpu->trace = g_array_index(cpu->traces, Trace*, cpu->privilege_level); |
| } |
| |
| static void vcpu_end(unsigned int vcpu_index) |
| { |
| Cpu *cpu = qemu_plugin_scoreboard_find(score, vcpu_index); |
| g_byte_array_free(cpu->buf, true); |
| |
| for (size_t i = 0; i < cpu->traces->len; ++i) { |
| Trace *t = g_array_index(cpu->traces, Trace*, i); |
| trace_free(t); |
| } |
| |
| g_array_free(cpu->traces, true); |
| callstack_free(cpu->cs); |
| memset(cpu, 0, sizeof(Cpu)); |
| } |
| |
| static void at_exit(qemu_plugin_id_t id, void *data) |
| { |
| bool system_emulation = (bool) data; |
| g_autoptr(GArray) traces = g_array_new(0, 0, sizeof(Trace *)); |
| |
| for (size_t i = 0; i < qemu_plugin_num_vcpus(); ++i) { |
| Cpu *cpu = qemu_plugin_scoreboard_find(score, i); |
| for (size_t j = 0; j < cpu->traces->len; ++j) { |
| Trace *t = g_array_index(cpu->traces, Trace*, j); |
| trace_flush(t, true); |
| g_array_append_val(traces, t); |
| } |
| } |
| |
| uftrace_write_map(system_emulation); |
| uftrace_write_info(traces); |
| uftrace_write_task(traces); |
| |
| for (size_t i = 0; i < qemu_plugin_num_vcpus(); ++i) { |
| vcpu_end(i); |
| } |
| |
| qemu_plugin_scoreboard_free(score); |
| } |
| |
| 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], "trace-privilege-level") == 0) { |
| if (!qemu_plugin_bool_parse(tokens[0], tokens[1], |
| &trace_privilege_level)) { |
| fprintf(stderr, "boolean argument parsing failed: %s\n", opt); |
| return -1; |
| } |
| } else { |
| fprintf(stderr, "option parsing failed: %s\n", opt); |
| return -1; |
| } |
| } |
| |
| if (!strcmp(info->target_name, "aarch64")) { |
| arch_ops = aarch64_ops; |
| } else if (!strcmp(info->target_name, "x86_64")) { |
| arch_ops = x64_ops; |
| } else { |
| fprintf(stderr, "plugin uftrace: %s target is not supported\n", |
| info->target_name); |
| return 1; |
| } |
| |
| score = qemu_plugin_scoreboard_new(sizeof(Cpu)); |
| qemu_plugin_register_vcpu_init_cb(id, vcpu_init); |
| qemu_plugin_register_atexit_cb(id, at_exit, (void *) info->system_emulation); |
| qemu_plugin_register_vcpu_tb_trans_cb(id, vcpu_tb_trans); |
| |
| return 0; |
| } |
