Pierrick Bouvier <pierrick.bouv...@linaro.org> writes:
> On 1/26/24 20:05, Alex Bennée wrote:
>> Pierrick Bouvier <pierrick.bouv...@linaro.org> writes:
>>
>>> For now, it simply performs instruction, bb and mem count, and ensure
>>> that inline vs callback versions have the same result. Later, we'll
>>> extend it when new inline operations are added.
>>>
>>> Use existing plugins to test everything works is a bit cumbersome, as
>>> different events are treated in different plugins. Thus, this new one.
>>>
>>> Signed-off-by: Pierrick Bouvier <pierrick.bouv...@linaro.org>
>>> ---
>>> tests/plugin/inline.c | 182 +++++++++++++++++++++++++++++++++++++++
>>> tests/plugin/meson.build | 2 +-
>>> 2 files changed, 183 insertions(+), 1 deletion(-)
>>> create mode 100644 tests/plugin/inline.c
>>>
>>> diff --git a/tests/plugin/inline.c b/tests/plugin/inline.c
>>> new file mode 100644
>>> index 00000000000..28d1c3b1e48
>>> --- /dev/null
>>> +++ b/tests/plugin/inline.c
>>> @@ -0,0 +1,182 @@
>>> +/*
>>> + * Copyright (C) 2023, Pierrick Bouvier <pierrick.bouv...@linaro.org>
>>> + *
>>> + * Demonstrates and tests usage of inline ops.
>>> + *
>>> + * License: GNU GPL, version 2 or later.
>>> + * See the COPYING file in the top-level directory.
>>> + */
>>> +
>>> +#include <glib.h>
>>> +#include <stdint.h>
>>> +#include <stdio.h>
>>> +
>>> +#include <qemu-plugin.h>
>>> +
>>> +typedef struct {
>>> + uint64_t count_tb;
>>> + uint64_t count_tb_inline;
>>> + uint64_t count_insn;
>>> + uint64_t count_insn_inline;
>>> + uint64_t count_mem;
>>> + uint64_t count_mem_inline;
>>> +} CPUCount;
>> I wonder if there is any way to enforce the structures being an
>> array of
>> 64 bit counts? I do worry the compiler might want day decide to do
>> something silly but legal leading to confusion.
>> I guess qemu_plugin_scoreboard_new could:
>> g_assert((element_size % sizeof(uint64_t)) == 0)
>>
>
> Given explaination on patch [02/14], do you see more that CPUCount
> could hold any type, and qemu_plugin_u64 allows to target a specific
> member in it?
>
> In general, qemu plugin runtime simply is given an offset and total
> size of the struct, so a compiled plugin can have any
> optimization/padding on this struct without this affecting the result.
>
>> ?
>>
>>> +static qemu_plugin_u64_t count_tb;
>>> +static qemu_plugin_u64_t count_tb_inline;
>>> +static qemu_plugin_u64_t count_insn;
>>> +static qemu_plugin_u64_t count_insn_inline;
>>> +static qemu_plugin_u64_t count_mem;
>>> +static qemu_plugin_u64_t count_mem_inline;
>> Can't this just be a non scoreboard instance of CPUCount?
>>
>
> We could always use:
> CPUCount* count = qemu_plugin_scoreboard_get(score, i);
> count->count_tb++;
I thought these where globals protected by a lock? I wasn't suggesting
hiding the abstraction behind the scoreboard API.
>
> However, the part where we sum all values would now need some glue
> code, which is longer and more error prone than having those
> definition here (and declaration in install function).
>
>>> +
>>> +static uint64_t global_count_tb;
>>> +static uint64_t global_count_insn;
>>> +static uint64_t global_count_mem;
>>> +static unsigned int max_cpu_index;
>>> +static GMutex tb_lock;
>>> +static GMutex insn_lock;
>>> +static GMutex mem_lock;
>>> +
>>> +QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION;
>>> +
>>> +static void stats_insn(void)
>>> +{
>>> + const uint64_t expected = global_count_insn;
>>> + const uint64_t per_vcpu = qemu_plugin_u64_sum(count_insn);
>>> + const uint64_t inl_per_vcpu =
>>> + qemu_plugin_u64_sum(count_insn_inline);
>>> + printf("insn: %" PRIu64 "\n", expected);
>>> + printf("insn: %" PRIu64 " (per vcpu)\n", per_vcpu);
>>> + printf("insn: %" PRIu64 " (per vcpu inline)\n", inl_per_vcpu);
>>> + g_assert(expected > 0);
>>> + g_assert(per_vcpu == expected);
>>> + g_assert(inl_per_vcpu == expected);
>>> +}
>>> +
>>> +static void stats_tb(void)
>>> +{
>>> + const uint64_t expected = global_count_tb;
>>> + const uint64_t per_vcpu = qemu_plugin_u64_sum(count_tb);
>>> + const uint64_t inl_per_vcpu =
>>> + qemu_plugin_u64_sum(count_tb_inline);
>>> + printf("tb: %" PRIu64 "\n", expected);
>>> + printf("tb: %" PRIu64 " (per vcpu)\n", per_vcpu);
>>> + printf("tb: %" PRIu64 " (per vcpu inline)\n", inl_per_vcpu);
>>> + g_assert(expected > 0);
>>> + g_assert(per_vcpu == expected);
>>> + g_assert(inl_per_vcpu == expected);
>>> +}
>>> +
>>> +static void stats_mem(void)
>>> +{
>>> + const uint64_t expected = global_count_mem;
>>> + const uint64_t per_vcpu = qemu_plugin_u64_sum(count_mem);
>>> + const uint64_t inl_per_vcpu =
>>> + qemu_plugin_u64_sum(count_mem_inline);
>>> + printf("mem: %" PRIu64 "\n", expected);
>>> + printf("mem: %" PRIu64 " (per vcpu)\n", per_vcpu);
>>> + printf("mem: %" PRIu64 " (per vcpu inline)\n", inl_per_vcpu);
>>> + g_assert(expected > 0);
>>> + g_assert(per_vcpu == expected);
>>> + g_assert(inl_per_vcpu == expected);
>>> +}
>>> +
>>> +static void plugin_exit(qemu_plugin_id_t id, void *udata)
>>> +{
>>> + const unsigned int num_cpus = qemu_plugin_scoreboard_size(counts);
>>> + g_assert(num_cpus == max_cpu_index + 1);
>>> +
>>> + for (int i = 0; i < num_cpus ; ++i) {
>>> + const uint64_t tb = *qemu_plugin_u64_get(count_tb, i);
>>> + const uint64_t tb_inline = *qemu_plugin_u64_get(count_tb_inline,
>>> i);
>>> + const uint64_t insn = *qemu_plugin_u64_get(count_insn, i);
>>> + const uint64_t insn_inline =
>>> *qemu_plugin_u64_get(count_insn_inline, i);
>>> + const uint64_t mem = *qemu_plugin_u64_get(count_mem, i);
>>> + const uint64_t mem_inline = *qemu_plugin_u64_get(count_mem_inline,
>>> i);
>>> + printf("cpu %d: tb (%" PRIu64 ", %" PRIu64 ") | "
>>> + "insn (%" PRIu64 ", %" PRIu64 ") | "
>>> + "mem (%" PRIu64 ", %" PRIu64 ")"
>>> + "\n",
>>> + i, tb, tb_inline, insn, insn_inline, mem, mem_inline);
>>> + g_assert(tb == tb_inline);
>>> + g_assert(insn == insn_inline);
>>> + g_assert(mem == mem_inline);
>>> + }
>>> +
>>> + stats_tb();
>>> + stats_insn();
>>> + stats_mem();
>>> +
>>> + qemu_plugin_scoreboard_free(counts);
>>> +}
>>> +
>>> +static void vcpu_tb_exec(unsigned int cpu_index, void *udata)
>>> +{
>>> + (*qemu_plugin_u64_get(count_tb, cpu_index))++;
>>> + g_mutex_lock(&tb_lock);
>>> + max_cpu_index = MAX(max_cpu_index, cpu_index);
>>> + global_count_tb++;
>>> + g_mutex_unlock(&tb_lock);
>>> +}
>>> +
>>> +static void vcpu_insn_exec(unsigned int cpu_index, void *udata)
>>> +{
>>> + (*qemu_plugin_u64_get(count_insn, cpu_index))++;
>>> + g_mutex_lock(&insn_lock);
>>> + global_count_insn++;
>>> + g_mutex_unlock(&insn_lock);
>>> +}
>>> +
>>> +static void vcpu_mem_access(unsigned int cpu_index,
>>> + qemu_plugin_meminfo_t info,
>>> + uint64_t vaddr,
>>> + void *userdata)
>>> +{
>>> + (*qemu_plugin_u64_get(count_mem, cpu_index))++;
>>> + g_mutex_lock(&mem_lock);
>>> + global_count_mem++;
>>> + g_mutex_unlock(&mem_lock);
>>> +}
>>> +
>>> +static void vcpu_tb_trans(qemu_plugin_id_t id, struct qemu_plugin_tb *tb)
>>> +{
>>> + qemu_plugin_register_vcpu_tb_exec_cb(
>>> + tb, vcpu_tb_exec, QEMU_PLUGIN_CB_NO_REGS, 0);
>>> + qemu_plugin_register_vcpu_tb_exec_inline_per_vcpu(
>>> + tb, QEMU_PLUGIN_INLINE_ADD_U64, count_tb_inline, 1);
>>> +
>>> + for (int idx = 0; idx < qemu_plugin_tb_n_insns(tb); ++idx) {
>>> + struct qemu_plugin_insn *insn = qemu_plugin_tb_get_insn(tb, idx);
>>> + qemu_plugin_register_vcpu_insn_exec_cb(
>>> + insn, vcpu_insn_exec, QEMU_PLUGIN_CB_NO_REGS, 0);
>>> + qemu_plugin_register_vcpu_insn_exec_inline_per_vcpu(
>>> + insn, QEMU_PLUGIN_INLINE_ADD_U64, count_insn_inline, 1);
>>> + qemu_plugin_register_vcpu_mem_cb(insn, &vcpu_mem_access,
>>> + QEMU_PLUGIN_CB_NO_REGS,
>>> + QEMU_PLUGIN_MEM_RW, 0);
>>> + qemu_plugin_register_vcpu_mem_inline_per_vcpu(
>>> + insn, QEMU_PLUGIN_MEM_RW,
>>> + QEMU_PLUGIN_INLINE_ADD_U64,
>>> + count_mem_inline, 1);
>>> + }
>>> +}
>>> +
>>> +QEMU_PLUGIN_EXPORT
>>> +int qemu_plugin_install(qemu_plugin_id_t id, const qemu_info_t *info,
>>> + int argc, char **argv)
>>> +{
>>> + counts = qemu_plugin_scoreboard_new(sizeof(CPUCount));
>>> + count_tb = qemu_plugin_u64_struct(counts, CPUCount, count_tb);
>>> + count_insn = qemu_plugin_u64_struct(counts, CPUCount, count_insn);
>>> + count_mem = qemu_plugin_u64_struct(counts, CPUCount, count_mem);
>>> + count_tb_inline = qemu_plugin_u64_struct(counts, CPUCount,
>>> count_tb_inline);
>>> + count_insn_inline =
>>> + qemu_plugin_u64_struct(counts, CPUCount, count_insn_inline);
>>> + count_mem_inline =
>>> + qemu_plugin_u64_struct(counts, CPUCount, count_mem_inline);
>>> + 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/tests/plugin/meson.build b/tests/plugin/meson.build
>>> index e18183aaeda..9eece5bab51 100644
>>> --- a/tests/plugin/meson.build
>>> +++ b/tests/plugin/meson.build
>>> @@ -1,6 +1,6 @@
>>> t = []
>>> if get_option('plugins')
>>> - foreach i : ['bb', 'empty', 'insn', 'mem', 'syscall']
>>> + foreach i : ['bb', 'empty', 'inline', 'insn', 'mem', 'syscall']
>>> if host_os == 'windows'
>>> t += shared_module(i, files(i + '.c') +
>>> '../../contrib/plugins/win32_linker.c',
>>> include_directories: '../../include/qemu',
>> Otherwise:
>> Reviewed-by: Alex Bennée <alex.ben...@linaro.org>
>>
--
Alex Bennée
Virtualisation Tech Lead @ Linaro
