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- Reorg cpu_tb_exec around setjmp.

Browse source 
- Use __attribute__((target)) for buffer_is_zero.
 - Add perfmap and jitdump for perf support.
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Merge tag 'pull-tcg-20230116' of https://gitlab.com/rth7680/qemu into staging

- Reorg cpu_tb_exec around setjmp.
- Use __attribute__((target)) for buffer_is_zero.
- Add perfmap and jitdump for perf support.

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# gpg: Good signature from "Richard Henderson <richard.henderson@linaro.org>" [full]
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* tag 'pull-tcg-20230116' of https://gitlab.com/rth7680/qemu:
  accel/tcg: Split out cpu_exec_{setjmp,loop}
  util/bufferiszero: Use __attribute__((target)) for avx2/avx512
  tcg: add perfmap and jitdump
  accel/tcg: Add debuginfo support
  linux-user: Clean up when exiting due to a signal

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This commit is contained in:
Peter Maydell 2023-01-17 10:24:15 +00:00
parent 2f8d6a88e4 61710a7e23
commit 7c9236d6d6
19 changed files with 763 additions and 101 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

111
accel/tcg/cpu-exec.c
View file

@ -909,64 +909,10 @@ static inline void cpu_loop_exec_tb(CPUState *cpu, TranslationBlock *tb,
/* main execution loop */
int cpu_exec(CPUState *cpu)
static int __attribute__((noinline))
cpu_exec_loop(CPUState *cpu, SyncClocks *sc)
{
int ret;
SyncClocks sc = { 0 };
/* replay_interrupt may need current_cpu */
current_cpu = cpu;
if (cpu_handle_halt(cpu)) {
return EXCP_HALTED;
}
rcu_read_lock();
cpu_exec_enter(cpu);
/* Calculate difference between guest clock and host clock.
* This delay includes the delay of the last cycle, so
* what we have to do is sleep until it is 0. As for the
* advance/delay we gain here, we try to fix it next time.
*/
init_delay_params(&sc, cpu);
/* prepare setjmp context for exception handling */
if (sigsetjmp(cpu->jmp_env, 0) != 0) {
#if defined(__clang__)
/*
* Some compilers wrongly smash all local variables after
* siglongjmp (the spec requires that only non-volatile locals
* which are changed between the sigsetjmp and siglongjmp are
* permitted to be trashed). There were bug reports for gcc
* 4.5.0 and clang. The bug is fixed in all versions of gcc
* that we support, but is still unfixed in clang:
* https://bugs.llvm.org/show_bug.cgi?id=21183
*
* Reload an essential local variable here for those compilers.
* Newer versions of gcc would complain about this code (-Wclobbered),
* so we only perform the workaround for clang.
*/
cpu = current_cpu;
#else
/* Non-buggy compilers preserve this; assert the correct value. */
g_assert(cpu == current_cpu);
#endif
#ifndef CONFIG_SOFTMMU
clear_helper_retaddr();
if (have_mmap_lock()) {
mmap_unlock();
}
#endif
if (qemu_mutex_iothread_locked()) {
qemu_mutex_unlock_iothread();
}
qemu_plugin_disable_mem_helpers(cpu);
assert_no_pages_locked();
}
/* if an exception is pending, we execute it here */
while (!cpu_handle_exception(cpu, &ret)) {
@ -1033,9 +979,60 @@ int cpu_exec(CPUState *cpu)
/* Try to align the host and virtual clocks
if the guest is in advance */
align_clocks(&sc, cpu);
align_clocks(sc, cpu);
}
}
return ret;
}
static int cpu_exec_setjmp(CPUState *cpu, SyncClocks *sc)
{
/* Prepare setjmp context for exception handling. */
if (unlikely(sigsetjmp(cpu->jmp_env, 0) != 0)) {
/* Non-buggy compilers preserve this; assert the correct value. */
g_assert(cpu == current_cpu);
#ifndef CONFIG_SOFTMMU
clear_helper_retaddr();
if (have_mmap_lock()) {
mmap_unlock();
}
#endif
if (qemu_mutex_iothread_locked()) {
qemu_mutex_unlock_iothread();
}
qemu_plugin_disable_mem_helpers(cpu);
assert_no_pages_locked();
}
return cpu_exec_loop(cpu, sc);
}
int cpu_exec(CPUState *cpu)
{
int ret;
SyncClocks sc = { 0 };
/* replay_interrupt may need current_cpu */
current_cpu = cpu;
if (cpu_handle_halt(cpu)) {
return EXCP_HALTED;
}
rcu_read_lock();
cpu_exec_enter(cpu);
/*
* Calculate difference between guest clock and host clock.
* This delay includes the delay of the last cycle, so
* what we have to do is sleep until it is 0. As for the
* advance/delay we gain here, we try to fix it next time.
*/
init_delay_params(&sc, cpu);
ret = cpu_exec_setjmp(cpu, &sc);
cpu_exec_exit(cpu);
rcu_read_unlock();

96
accel/tcg/debuginfo.c Normal file
View file

@ -0,0 +1,96 @@
/*
* Debug information support.
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "qemu/osdep.h"
#include "qemu/lockable.h"
#include <elfutils/libdwfl.h>
#include "debuginfo.h"
static QemuMutex lock;
static Dwfl *dwfl;
static const Dwfl_Callbacks dwfl_callbacks = {
.find_elf = NULL,
.find_debuginfo = dwfl_standard_find_debuginfo,
.section_address = NULL,
.debuginfo_path = NULL,
};
__attribute__((constructor))
static void debuginfo_init(void)
{
qemu_mutex_init(&lock);
}
void debuginfo_report_elf(const char *name, int fd, uint64_t bias)
{
QEMU_LOCK_GUARD(&lock);
if (dwfl) {
dwfl_report_begin_add(dwfl);
} else {
dwfl = dwfl_begin(&dwfl_callbacks);
}
if (dwfl) {
dwfl_report_elf(dwfl, name, name, fd, bias, true);
dwfl_report_end(dwfl, NULL, NULL);
}
}
void debuginfo_lock(void)
{
qemu_mutex_lock(&lock);
}
void debuginfo_query(struct debuginfo_query *q, size_t n)
{
const char *symbol, *file;
Dwfl_Module *dwfl_module;
Dwfl_Line *dwfl_line;
GElf_Off dwfl_offset;
GElf_Sym dwfl_sym;
size_t i;
int line;
if (!dwfl) {
return;
}
for (i = 0; i < n; i++) {
dwfl_module = dwfl_addrmodule(dwfl, q[i].address);
if (!dwfl_module) {
continue;
}
if (q[i].flags & DEBUGINFO_SYMBOL) {
symbol = dwfl_module_addrinfo(dwfl_module, q[i].address,
&dwfl_offset, &dwfl_sym,
NULL, NULL, NULL);
if (symbol) {
q[i].symbol = symbol;
q[i].offset = dwfl_offset;
}
}
if (q[i].flags & DEBUGINFO_LINE) {
dwfl_line = dwfl_module_getsrc(dwfl_module, q[i].address);
if (dwfl_line) {
file = dwfl_lineinfo(dwfl_line, NULL, &line, 0, NULL, NULL);
if (file) {
q[i].file = file;
q[i].line = line;
}
}
}
}
}
void debuginfo_unlock(void)
{
qemu_mutex_unlock(&lock);
}

77
accel/tcg/debuginfo.h Normal file
View file

@ -0,0 +1,77 @@
/*
* Debug information support.
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#ifndef ACCEL_TCG_DEBUGINFO_H
#define ACCEL_TCG_DEBUGINFO_H
/*
* Debuginfo describing a certain address.
*/
struct debuginfo_query {
uint64_t address; /* Input: address. */
int flags; /* Input: debuginfo subset. */
const char *symbol; /* Symbol that the address is part of. */
uint64_t offset; /* Offset from the symbol. */
const char *file; /* Source file associated with the address. */
int line; /* Line number in the source file. */
};
/*
* Debuginfo subsets.
*/
#define DEBUGINFO_SYMBOL BIT(1)
#define DEBUGINFO_LINE BIT(2)
#if defined(CONFIG_TCG) && defined(CONFIG_LIBDW)
/*
* Load debuginfo for the specified guest ELF image.
* Return true on success, false on failure.
*/
void debuginfo_report_elf(const char *name, int fd, uint64_t bias);
/*
* Take the debuginfo lock.
*/
void debuginfo_lock(void);
/*
* Fill each on N Qs with the debuginfo about Q->ADDRESS as specified by
* Q->FLAGS:
*
* - DEBUGINFO_SYMBOL: update Q->SYMBOL and Q->OFFSET. If symbol debuginfo is
* missing, then leave them as is.
* - DEBUINFO_LINE: update Q->FILE and Q->LINE. If line debuginfo is missing,
* then leave them as is.
*
* This function must be called under the debuginfo lock. The results can be
* accessed only until the debuginfo lock is released.
*/
void debuginfo_query(struct debuginfo_query *q, size_t n);
/*
* Release the debuginfo lock.
*/
void debuginfo_unlock(void);
#else
static inline void debuginfo_report_elf(const char *image_name, int image_fd,
uint64_t load_bias)
{
}
static inline void debuginfo_lock(void)
{
}
static inline void debuginfo_query(struct debuginfo_query *q, size_t n)
{
}
static inline void debuginfo_unlock(void)
{
}
#endif
#endif

2
accel/tcg/meson.build
View file

@ -12,6 +12,8 @@ tcg_ss.add(files(
tcg_ss.add(when: 'CONFIG_USER_ONLY', if_true: files('user-exec.c'))
tcg_ss.add(when: 'CONFIG_SOFTMMU', if_false: files('user-exec-stub.c'))
tcg_ss.add(when: 'CONFIG_PLUGIN', if_true: [files('plugin-gen.c')])
tcg_ss.add(when: libdw, if_true: files('debuginfo.c'))
tcg_ss.add(when: 'CONFIG_LINUX', if_true: files('perf.c'))
specific_ss.add_all(when: 'CONFIG_TCG', if_true: tcg_ss)
specific_ss.add(when: ['CONFIG_SOFTMMU', 'CONFIG_TCG'], if_true: files(

375
accel/tcg/perf.c Normal file
View file

@ -0,0 +1,375 @@
/*
* Linux perf perf-<pid>.map and jit-<pid>.dump integration.
*
* The jitdump spec can be found at [1].
*
* [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/plain/tools/perf/Documentation/jitdump-specification.txt
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "qemu/osdep.h"
#include "elf.h"
#include "exec/exec-all.h"
#include "qemu/timer.h"
#include "tcg/tcg.h"
#include "debuginfo.h"
#include "perf.h"
static FILE *safe_fopen_w(const char *path)
{
int saved_errno;
FILE *f;
int fd;
/* Delete the old file, if any. */
unlink(path);
/* Avoid symlink attacks by using O_CREAT | O_EXCL. */
fd = open(path, O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR);
if (fd == -1) {
return NULL;
}
/* Convert fd to FILE*. */
f = fdopen(fd, "w");
if (f == NULL) {
saved_errno = errno;
close(fd);
errno = saved_errno;
return NULL;
}
return f;
}
static FILE *perfmap;
void perf_enable_perfmap(void)
{
char map_file[32];
snprintf(map_file, sizeof(map_file), "/tmp/perf-%d.map", getpid());
perfmap = safe_fopen_w(map_file);
if (perfmap == NULL) {
warn_report("Could not open %s: %s, proceeding without perfmap",
map_file, strerror(errno));
}
}
/* Get PC and size of code JITed for guest instruction #INSN. */
static void get_host_pc_size(uintptr_t *host_pc, uint16_t *host_size,
const void *start, size_t insn)
{
uint16_t start_off = insn ? tcg_ctx->gen_insn_end_off[insn - 1] : 0;
if (host_pc) {
*host_pc = (uintptr_t)start + start_off;
}
if (host_size) {
*host_size = tcg_ctx->gen_insn_end_off[insn] - start_off;
}
}
static const char *pretty_symbol(const struct debuginfo_query *q, size_t *len)
{
static __thread char buf[64];
int tmp;
if (!q->symbol) {
tmp = snprintf(buf, sizeof(buf), "guest-0x%"PRIx64, q->address);
if (len) {
*len = MIN(tmp + 1, sizeof(buf));
}
return buf;
}
if (!q->offset) {
if (len) {
*len = strlen(q->symbol) + 1;
}
return q->symbol;
}
tmp = snprintf(buf, sizeof(buf), "%s+0x%"PRIx64, q->symbol, q->offset);
if (len) {
*len = MIN(tmp + 1, sizeof(buf));
}
return buf;
}
static void write_perfmap_entry(const void *start, size_t insn,
const struct debuginfo_query *q)
{
uint16_t host_size;
uintptr_t host_pc;
get_host_pc_size(&host_pc, &host_size, start, insn);
fprintf(perfmap, "%"PRIxPTR" %"PRIx16" %s\n",
host_pc, host_size, pretty_symbol(q, NULL));
}
static FILE *jitdump;
#define JITHEADER_MAGIC 0x4A695444
#define JITHEADER_VERSION 1
struct jitheader {
uint32_t magic;
uint32_t version;
uint32_t total_size;
uint32_t elf_mach;
uint32_t pad1;
uint32_t pid;
uint64_t timestamp;
uint64_t flags;
};
enum jit_record_type {
JIT_CODE_LOAD = 0,
JIT_CODE_DEBUG_INFO = 2,
};
struct jr_prefix {
uint32_t id;
uint32_t total_size;
uint64_t timestamp;
};
struct jr_code_load {
struct jr_prefix p;
uint32_t pid;
uint32_t tid;
uint64_t vma;
uint64_t code_addr;
uint64_t code_size;
uint64_t code_index;
};
struct debug_entry {
uint64_t addr;
int lineno;
int discrim;
const char name[];
};
struct jr_code_debug_info {
struct jr_prefix p;
uint64_t code_addr;
uint64_t nr_entry;
struct debug_entry entries[];
};
static uint32_t get_e_machine(void)
{
Elf64_Ehdr elf_header;
FILE *exe;
size_t n;
QEMU_BUILD_BUG_ON(offsetof(Elf32_Ehdr, e_machine) !=
offsetof(Elf64_Ehdr, e_machine));
exe = fopen("/proc/self/exe", "r");
if (exe == NULL) {
return EM_NONE;
}
n = fread(&elf_header, sizeof(elf_header), 1, exe);
fclose(exe);
if (n != 1) {
return EM_NONE;
}
return elf_header.e_machine;
}
void perf_enable_jitdump(void)
{
struct jitheader header;
char jitdump_file[32];
void *perf_marker;
if (!use_rt_clock) {
warn_report("CLOCK_MONOTONIC is not available, proceeding without jitdump");
return;
}
snprintf(jitdump_file, sizeof(jitdump_file), "jit-%d.dump", getpid());
jitdump = safe_fopen_w(jitdump_file);
if (jitdump == NULL) {
warn_report("Could not open %s: %s, proceeding without jitdump",
jitdump_file, strerror(errno));
return;
}
/*
* `perf inject` will see that the mapped file name in the corresponding
* PERF_RECORD_MMAP or PERF_RECORD_MMAP2 event is of the form jit-%d.dump
* and will process it as a jitdump file.
*/
perf_marker = mmap(NULL, qemu_real_host_page_size(), PROT_READ | PROT_EXEC,
MAP_PRIVATE, fileno(jitdump), 0);
if (perf_marker == MAP_FAILED) {
warn_report("Could not map %s: %s, proceeding without jitdump",
jitdump_file, strerror(errno));
fclose(jitdump);
jitdump = NULL;
return;
}
header.magic = JITHEADER_MAGIC;
header.version = JITHEADER_VERSION;
header.total_size = sizeof(header);
header.elf_mach = get_e_machine();
header.pad1 = 0;
header.pid = getpid();
header.timestamp = get_clock();
header.flags = 0;
fwrite(&header, sizeof(header), 1, jitdump);
}
void perf_report_prologue(const void *start, size_t size)
{
if (perfmap) {
fprintf(perfmap, "%"PRIxPTR" %zx tcg-prologue-buffer\n",
(uintptr_t)start, size);
}
}
/* Write a JIT_CODE_DEBUG_INFO jitdump entry. */
static void write_jr_code_debug_info(const void *start,
const struct debuginfo_query *q,
size_t icount)
{
struct jr_code_debug_info rec;
struct debug_entry ent;
uintptr_t host_pc;
int insn;
/* Write the header. */
rec.p.id = JIT_CODE_DEBUG_INFO;
rec.p.total_size = sizeof(rec) + sizeof(ent) + 1;
rec.p.timestamp = get_clock();
rec.code_addr = (uintptr_t)start;
rec.nr_entry = 1;
for (insn = 0; insn < icount; insn++) {
if (q[insn].file) {
rec.p.total_size += sizeof(ent) + strlen(q[insn].file) + 1;
rec.nr_entry++;
}
}
fwrite(&rec, sizeof(rec), 1, jitdump);
/* Write the main debug entries. */
for (insn = 0; insn < icount; insn++) {
if (q[insn].file) {
get_host_pc_size(&host_pc, NULL, start, insn);
ent.addr = host_pc;
ent.lineno = q[insn].line;
ent.discrim = 0;
fwrite(&ent, sizeof(ent), 1, jitdump);
fwrite(q[insn].file, strlen(q[insn].file) + 1, 1, jitdump);
}
}
/* Write the trailing debug_entry. */
ent.addr = (uintptr_t)start + tcg_ctx->gen_insn_end_off[icount - 1];
ent.lineno = 0;
ent.discrim = 0;
fwrite(&ent, sizeof(ent), 1, jitdump);
fwrite("", 1, 1, jitdump);
}
/* Write a JIT_CODE_LOAD jitdump entry. */
static void write_jr_code_load(const void *start, uint16_t host_size,
const struct debuginfo_query *q)
{
static uint64_t code_index;
struct jr_code_load rec;
const char *symbol;
size_t symbol_size;
symbol = pretty_symbol(q, &symbol_size);
rec.p.id = JIT_CODE_LOAD;
rec.p.total_size = sizeof(rec) + symbol_size + host_size;
rec.p.timestamp = get_clock();
rec.pid = getpid();
rec.tid = qemu_get_thread_id();
rec.vma = (uintptr_t)start;
rec.code_addr = (uintptr_t)start;
rec.code_size = host_size;
rec.code_index = code_index++;
fwrite(&rec, sizeof(rec), 1, jitdump);
fwrite(symbol, symbol_size, 1, jitdump);
fwrite(start, host_size, 1, jitdump);
}
void perf_report_code(uint64_t guest_pc, TranslationBlock *tb,
const void *start)
{
struct debuginfo_query *q;
size_t insn;
if (!perfmap && !jitdump) {
return;
}
q = g_try_malloc0_n(tb->icount, sizeof(*q));
if (!q) {
return;
}
debuginfo_lock();
/* Query debuginfo for each guest instruction. */
for (insn = 0; insn < tb->icount; insn++) {
/* FIXME: This replicates the restore_state_to_opc() logic. */
q[insn].address = tcg_ctx->gen_insn_data[insn][0];
if (TARGET_TB_PCREL) {
q[insn].address |= (guest_pc & TARGET_PAGE_MASK);
} else {
#if defined(TARGET_I386)
q[insn].address -= tb->cs_base;
#endif
}
q[insn].flags = DEBUGINFO_SYMBOL | (jitdump ? DEBUGINFO_LINE : 0);
}
debuginfo_query(q, tb->icount);
/* Emit perfmap entries if needed. */
if (perfmap) {
flockfile(perfmap);
for (insn = 0; insn < tb->icount; insn++) {
write_perfmap_entry(start, insn, &q[insn]);
}
funlockfile(perfmap);
}
/* Emit jitdump entries if needed. */
if (jitdump) {
flockfile(jitdump);
write_jr_code_debug_info(start, q, tb->icount);
write_jr_code_load(start, tcg_ctx->gen_insn_end_off[tb->icount - 1],
q);
funlockfile(jitdump);
}
debuginfo_unlock();
g_free(q);
}
void perf_exit(void)
{
if (perfmap) {
fclose(perfmap);
perfmap = NULL;
}
if (jitdump) {
fclose(jitdump);
jitdump = NULL;
}
}

49
accel/tcg/perf.h Normal file
View file

@ -0,0 +1,49 @@
/*
* Linux perf perf-<pid>.map and jit-<pid>.dump integration.
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#ifndef ACCEL_TCG_PERF_H
#define ACCEL_TCG_PERF_H
#if defined(CONFIG_TCG) && defined(CONFIG_LINUX)
/* Start writing perf-<pid>.map. */
void perf_enable_perfmap(void);
/* Start writing jit-<pid>.dump. */
void perf_enable_jitdump(void);
/* Add information about TCG prologue to profiler maps. */
void perf_report_prologue(const void *start, size_t size);
/* Add information about JITted guest code to profiler maps. */
void perf_report_code(uint64_t guest_pc, TranslationBlock *tb,
const void *start);
/* Stop writing perf-<pid>.map and/or jit-<pid>.dump. */
void perf_exit(void);
#else
static inline void perf_enable_perfmap(void)
{
}
static inline void perf_enable_jitdump(void)
{
}
static inline void perf_report_prologue(const void *start, size_t size)
{
}
static inline void perf_report_code(uint64_t guest_pc, TranslationBlock *tb,
const void *start)
{
}
static inline void perf_exit(void)
{
}
#endif
#endif

7
accel/tcg/translate-all.c
View file

@ -62,6 +62,7 @@
#include "tb-hash.h"
#include "tb-context.h"
#include "internal.h"
#include "perf.h"
/* Make sure all possible CPU event bits fit in tb->trace_vcpu_dstate */
QEMU_BUILD_BUG_ON(CPU_TRACE_DSTATE_MAX_EVENTS >
@ -406,6 +407,12 @@ TranslationBlock *tb_gen_code(CPUState *cpu,
}
tb->tc.size = gen_code_size;
/*
* For TARGET_TB_PCREL, attribute all executions of the generated
* code to its first mapping.
*/
perf_report_code(pc, tb, tcg_splitwx_to_rx(gen_code_buf));
#ifdef CONFIG_PROFILER
qatomic_set(&prof->code_time, prof->code_time + profile_getclock() - ti);
qatomic_set(&prof->code_in_len, prof->code_in_len + tb->size);

23
docs/devel/tcg.rst
View file

@ -188,3 +188,26 @@ memory areas instead calls out to C code for device emulation.
Finally, the MMU helps tracking dirty pages and pages pointed to by
translation blocks.
Profiling JITted code
---------------------
The Linux ``perf`` tool will treat all JITted code as a single block as
unlike the main code it can't use debug information to link individual
program counter samples with larger functions. To overcome this
limitation you can use the ``-perfmap`` or the ``-jitdump`` option to generate
map files. ``-perfmap`` is lightweight and produces only guest-host mappings.
``-jitdump`` additionally saves JITed code and guest debug information (if
available); its output needs to be integrated with the ``perf.data`` file
before the final report can be viewed.
.. code::
perf record $QEMU -perfmap $REMAINING_ARGS
perf report
perf record -k 1 $QEMU -jitdump $REMAINING_ARGS
DEBUGINFOD_URLS= perf inject -j -i perf.data -o perf.data.jitted
perf report -i perf.data.jitted
Note that qemu-system generates mappings only for ``-kernel`` files in ELF
format.

5
hw/core/loader.c
View file

@ -61,6 +61,7 @@
#include "hw/boards.h"
#include "qemu/cutils.h"
#include "sysemu/runstate.h"
#include "accel/tcg/debuginfo.h"
#include <zlib.h>
@ -503,6 +504,10 @@ ssize_t load_elf_ram_sym(const char *filename,
clear_lsb, data_swab, as, load_rom, sym_cb);
}
if (ret != ELF_LOAD_FAILED) {
debuginfo_report_elf(filename, fd, 0);
}
fail:
close(fd);
return ret;

3
linux-user/elfload.c
View file

@ -19,6 +19,7 @@
#include "qemu/selfmap.h"
#include "qapi/error.h"
#include "target_signal.h"
#include "accel/tcg/debuginfo.h"
#ifdef _ARCH_PPC64
#undef ARCH_DLINFO
@ -3261,6 +3262,8 @@ static void load_elf_image(const char *image_name, int image_fd,
load_symbols(ehdr, image_fd, load_bias);
}
debuginfo_report_elf(image_name, image_fd, load_bias);
mmap_unlock();
close(image_fd);

2
linux-user/exit.c
View file

@ -17,6 +17,7 @@
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#include "qemu/osdep.h"
#include "accel/tcg/perf.h"
#include "exec/gdbstub.h"
#include "qemu.h"
#include "user-internals.h"
@ -38,4 +39,5 @@ void preexit_cleanup(CPUArchState *env, int code)
#endif
gdb_exit(code);
qemu_plugin_user_exit();
perf_exit();
}

15
linux-user/main.c
View file

@ -53,6 +53,7 @@
#include "signal-common.h"
#include "loader.h"
#include "user-mmap.h"
#include "accel/tcg/perf.h"
#ifdef CONFIG_SEMIHOSTING
#include "semihosting/semihost.h"
@ -423,6 +424,16 @@ static void handle_arg_abi_call0(const char *arg)
}
#endif
static void handle_arg_perfmap(const char *arg)
{
perf_enable_perfmap();
}
static void handle_arg_jitdump(const char *arg)
{
perf_enable_jitdump();
}
static QemuPluginList plugins = QTAILQ_HEAD_INITIALIZER(plugins);
#ifdef CONFIG_PLUGIN
@ -493,6 +504,10 @@ static const struct qemu_argument arg_table[] = {
{"xtensa-abi-call0", "QEMU_XTENSA_ABI_CALL0", false, handle_arg_abi_call0,
"", "assume CALL0 Xtensa ABI"},
#endif
{"perfmap", "QEMU_PERFMAP", false, handle_arg_perfmap,
"", "Generate a /tmp/perf-${pid}.map file for perf"},
{"jitdump", "QEMU_JITDUMP", false, handle_arg_jitdump,
"", "Generate a jit-${pid}.dump file for perf"},
{NULL, NULL, false, NULL, NULL, NULL}
};

1
linux-user/meson.build
View file

@ -22,6 +22,7 @@ linux_user_ss.add(files(
'uname.c',
))
linux_user_ss.add(rt)
linux_user_ss.add(libdw)
linux_user_ss.add(when: 'TARGET_HAS_BFLT', if_true: files('flatload.c'))
linux_user_ss.add(when: 'TARGET_I386', if_true: files('vm86.c'))

8
linux-user/signal.c
View file

@ -695,7 +695,7 @@ void cpu_loop_exit_sigbus(CPUState *cpu, target_ulong addr,
/* abort execution with signal */
static G_NORETURN
void dump_core_and_abort(int target_sig)
void dump_core_and_abort(CPUArchState *cpu_env, int target_sig)
{
CPUState *cpu = thread_cpu;
CPUArchState *env = cpu->env_ptr;
@ -724,6 +724,8 @@ void dump_core_and_abort(int target_sig)
target_sig, strsignal(host_sig), "core dumped" );
}
preexit_cleanup(cpu_env, 128 + target_sig);
/* The proper exit code for dying from an uncaught signal is
* -<signal>. The kernel doesn't allow exit() or _exit() to pass
* a negative value. To get the proper exit code we need to
@ -1058,12 +1060,12 @@ static void handle_pending_signal(CPUArchState *cpu_env, int sig,
sig != TARGET_SIGURG &&
sig != TARGET_SIGWINCH &&
sig != TARGET_SIGCONT) {
dump_core_and_abort(sig);
dump_core_and_abort(cpu_env, sig);
}
} else if (handler == TARGET_SIG_IGN) {
/* ignore sig */
} else if (handler == TARGET_SIG_ERR) {
dump_core_and_abort(sig);
dump_core_and_abort(cpu_env, sig);
} else {
/* compute the blocked signals during the handler execution */
sigset_t *blocked_set;

16
meson.build
View file

@ -1648,6 +1648,12 @@ if libbpf.found() and not cc.links('''
endif
endif
# libdw
libdw = dependency('libdw',
method: 'pkg-config',
kwargs: static_kwargs,
required: false)
#################
# config-host.h #
#################
@ -1923,6 +1929,7 @@ config_host_data.set('CONFIG_DBUS_DISPLAY', dbus_display)
config_host_data.set('CONFIG_CFI', get_option('cfi'))
config_host_data.set('CONFIG_SELINUX', selinux.found())
config_host_data.set('CONFIG_XEN_BACKEND', xen.found())
config_host_data.set('CONFIG_LIBDW', libdw.found())
if xen.found()
# protect from xen.version() having less than three components
xen_version = xen.version().split('.') + ['0', '0']
@ -2331,11 +2338,9 @@ config_host_data.set('CONFIG_CPUID_H', have_cpuid_h)
config_host_data.set('CONFIG_AVX2_OPT', get_option('avx2') \
.require(have_cpuid_h, error_message: 'cpuid.h not available, cannot enable AVX2') \
.require(cc.links('''
#pragma GCC push_options
#pragma GCC target("avx2")
#include <cpuid.h>
#include <immintrin.h>
static int bar(void *a) {
static int __attribute__((target("avx2"))) bar(void *a) {
__m256i x = *(__m256i *)a;
return _mm256_testz_si256(x, x);
}
@ -2345,11 +2350,9 @@ config_host_data.set('CONFIG_AVX2_OPT', get_option('avx2') \
config_host_data.set('CONFIG_AVX512F_OPT', get_option('avx512f') \
.require(have_cpuid_h, error_message: 'cpuid.h not available, cannot enable AVX512F') \
.require(cc.links('''
#pragma GCC push_options
#pragma GCC target("avx512f")
#include <cpuid.h>
#include <immintrin.h>
static int bar(void *a) {
static int __attribute__((target("avx512f"))) bar(void *a) {
__m512i x = *(__m512i *)a;
return _mm512_test_epi64_mask(x, x);
}
@ -3976,6 +3979,7 @@ summary_info += {'libudev': libudev}
# Dummy dependency, keep .found()
summary_info += {'FUSE lseek': fuse_lseek.found()}
summary_info += {'selinux': selinux}
summary_info += {'libdw': libdw}
summary(summary_info, bool_yn: true, section: 'Dependencies')
if not supported_cpus.contains(cpu)

20
qemu-options.hx
View file

@ -4838,6 +4838,26 @@ SRST
Enable synchronization profiling.
ERST
#if defined(CONFIG_TCG) && defined(CONFIG_LINUX)
DEF("perfmap", 0, QEMU_OPTION_perfmap,
"-perfmap generate a /tmp/perf-${pid}.map file for perf\n",
QEMU_ARCH_ALL)
SRST
``-perfmap``
Generate a map file for Linux perf tools that will allow basic profiling
information to be broken down into basic blocks.
ERST
DEF("jitdump", 0, QEMU_OPTION_jitdump,
"-jitdump generate a jit-${pid}.dump file for perf\n",
QEMU_ARCH_ALL)
SRST
``-jitdump``
Generate a dump file for Linux perf tools that maps basic blocks to symbol
names, line numbers and JITted code.
ERST
#endif
DEFHEADING()
DEFHEADING(Generic object creation:)

11
softmmu/vl.c
View file

@ -96,6 +96,9 @@
#include "fsdev/qemu-fsdev.h"
#endif
#include "sysemu/qtest.h"
#ifdef CONFIG_TCG
#include "accel/tcg/perf.h"
#endif
#include "disas/disas.h"
@ -2926,6 +2929,14 @@ void qemu_init(int argc, char **argv)
case QEMU_OPTION_DFILTER:
qemu_set_dfilter_ranges(optarg, &error_fatal);
break;
#if defined(CONFIG_TCG) && defined(CONFIG_LINUX)
case QEMU_OPTION_perfmap:
perf_enable_perfmap();
break;
case QEMU_OPTION_jitdump:
perf_enable_jitdump();
break;
#endif
case QEMU_OPTION_seed:
qemu_guest_random_seed_main(optarg, &error_fatal);
break;

2
tcg/tcg.c
View file

@ -61,6 +61,7 @@
#include "exec/log.h"
#include "tcg/tcg-ldst.h"
#include "tcg-internal.h"
#include "accel/tcg/perf.h"
/* Forward declarations for functions declared in tcg-target.c.inc and
used here. */
@ -913,6 +914,7 @@ void tcg_prologue_init(TCGContext *s)
#endif
prologue_size = tcg_current_code_size(s);
perf_report_prologue(s->code_gen_ptr, prologue_size);
#ifndef CONFIG_TCG_INTERPRETER
flush_idcache_range((uintptr_t)tcg_splitwx_to_rx(s->code_buf),

41
util/bufferiszero.c
View file

@ -64,18 +64,11 @@ buffer_zero_int(const void *buf, size_t len)
}
#if defined(CONFIG_AVX512F_OPT) || defined(CONFIG_AVX2_OPT) || defined(__SSE2__)
/* Do not use push_options pragmas unnecessarily, because clang
* does not support them.
*/
#if defined(CONFIG_AVX512F_OPT) || defined(CONFIG_AVX2_OPT)
#pragma GCC push_options
#pragma GCC target("sse2")
#endif
#include <emmintrin.h>
#include <immintrin.h>
/* Note that each of these vectorized functions require len >= 64. */
static bool
static bool __attribute__((target("sse2")))
buffer_zero_sse2(const void *buf, size_t len)
{
__m128i t = _mm_loadu_si128(buf);
@ -104,20 +97,9 @@ buffer_zero_sse2(const void *buf, size_t len)
return _mm_movemask_epi8(_mm_cmpeq_epi8(t, zero)) == 0xFFFF;
}
#if defined(CONFIG_AVX512F_OPT) || defined(CONFIG_AVX2_OPT)
#pragma GCC pop_options
#endif
#ifdef CONFIG_AVX2_OPT
/* Note that due to restrictions/bugs wrt __builtin functions in gcc <= 4.8,
* the includes have to be within the corresponding push_options region, and
* therefore the regions themselves have to be ordered with increasing ISA.
*/
#pragma GCC push_options
#pragma GCC target("sse4")
#include <smmintrin.h>
static bool
static bool __attribute__((target("sse4")))
buffer_zero_sse4(const void *buf, size_t len)
{
__m128i t = _mm_loadu_si128(buf);
@ -145,12 +127,7 @@ buffer_zero_sse4(const void *buf, size_t len)
return _mm_testz_si128(t, t);
}
#pragma GCC pop_options
#pragma GCC push_options
#pragma GCC target("avx2")
#include <immintrin.h>
static bool
static bool __attribute__((target("avx2")))
buffer_zero_avx2(const void *buf, size_t len)
{
/* Begin with an unaligned head of 32 bytes. */
@ -176,15 +153,10 @@ buffer_zero_avx2(const void *buf, size_t len)
return _mm256_testz_si256(t, t);
}
#pragma GCC pop_options
#endif /* CONFIG_AVX2_OPT */
#ifdef CONFIG_AVX512F_OPT
#pragma GCC push_options
#pragma GCC target("avx512f")
#include <immintrin.h>
static bool
static bool __attribute__((target("avx512f")))
buffer_zero_avx512(const void *buf, size_t len)
{
/* Begin with an unaligned head of 64 bytes. */
@ -210,8 +182,7 @@ buffer_zero_avx512(const void *buf, size_t len)
return !_mm512_test_epi64_mask(t, t);
}
#pragma GCC pop_options
#endif
#endif /* CONFIG_AVX512F_OPT */
/* Note that for test_buffer_is_zero_next_accel, the most preferred