From: Hao Xiang <hao.xi...@linux.dev>
* DSA device open and close.
* DSA group contains multiple DSA devices.
* DSA group configure/start/stop/clean.
Signed-off-by: Hao Xiang <hao.xi...@linux.dev>
Signed-off-by: Bryan Zhang <bryan.zh...@bytedance.com>
Signed-off-by: Yichen Wang <yichen.w...@bytedance.com>
---
include/qemu/dsa.h | 86 +++++++++++++
util/dsa.c | 303 +++++++++++++++++++++++++++++++++++++++++++++
util/meson.build | 3 +
3 files changed, 392 insertions(+)
create mode 100644 include/qemu/dsa.h
create mode 100644 util/dsa.c
diff --git a/include/qemu/dsa.h b/include/qemu/dsa.h
new file mode 100644
index 0000000000..29b60654e9
--- /dev/null
+++ b/include/qemu/dsa.h
@@ -0,0 +1,86 @@
+/*
+ * Interface for using Intel Data Streaming Accelerator to offload certain
+ * background operations.
+ *
+ * Copyright (C) Bytedance Ltd.
+ *
+ * Authors:
+ * Hao Xiang <hao.xi...@bytedance.com>
+ * Yichen Wang <yichen.w...@bytedance.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#ifndef QEMU_DSA_H
+#define QEMU_DSA_H
+
+#include "qemu/error-report.h"
+#include "qemu/thread.h"
+#include "qemu/queue.h"
+
+#ifdef CONFIG_DSA_OPT
+
+#pragma GCC push_options
+#pragma GCC target("enqcmd")
+
+#include <linux/idxd.h>
+#include "x86intrin.h"
+
+/**
+ * @brief Initializes DSA devices.
+ *
+ * @param dsa_parameter A list of DSA device path from migration parameter.
+ *
+ * @return int Zero if successful, otherwise non zero.
+ */
+int qemu_dsa_init(const char *dsa_parameter, Error **errp);
+
+/**
+ * @brief Start logic to enable using DSA.
+ */
+void qemu_dsa_start(void);
+
+/**
+ * @brief Stop the device group and the completion thread.
+ */
+void qemu_dsa_stop(void);
+
+/**
+ * @brief Clean up system resources created for DSA offloading.
+ */
+void qemu_dsa_cleanup(void);
+
+/**
+ * @brief Check if DSA is running.
+ *
+ * @return True if DSA is running, otherwise false.
+ */
+bool qemu_dsa_is_running(void);
+
+#else
+
+static inline bool qemu_dsa_is_running(void)
+{
+ return false;
+}
+
+static inline int qemu_dsa_init(const char *dsa_parameter, Error **errp)
+{
+ if (dsa_parameter != NULL && strlen(dsa_parameter) != 0) {
+ error_setg(errp, "DSA is not supported.");
+ return -1;
+ }
+
+ return 0;
+}
+
+static inline void qemu_dsa_start(void) {}
+
+static inline void qemu_dsa_stop(void) {}
+
+static inline void qemu_dsa_cleanup(void) {}
+
+#endif
+
+#endif
diff --git a/util/dsa.c b/util/dsa.c
new file mode 100644
index 0000000000..cdb0b9dda2
--- /dev/null
+++ b/util/dsa.c
@@ -0,0 +1,303 @@
+/*
+ * Use Intel Data Streaming Accelerator to offload certain background
+ * operations.
+ *
+ * Copyright (C) Bytedance Ltd.
+ *
+ * Authors:
+ * Hao Xiang <hao.xi...@bytedance.com>
+ * Bryan Zhang <bryan.zh...@bytedance.com>
+ * Yichen Wang <yichen.w...@bytedance.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "qemu/queue.h"
+#include "qemu/memalign.h"
+#include "qemu/lockable.h"
+#include "qemu/cutils.h"
+#include "qemu/dsa.h"
+#include "qemu/bswap.h"
+#include "qemu/error-report.h"
+#include "qemu/rcu.h"
+
+#pragma GCC push_options
+#pragma GCC target("enqcmd")
+
+#include <linux/idxd.h>
+#include "x86intrin.h"
+
+#define DSA_WQ_SIZE 4096
+#define MAX_DSA_DEVICES 16
+
+typedef QSIMPLEQ_HEAD(dsa_task_queue, dsa_batch_task) dsa_task_queue;
+
+typedef struct {
+ void *work_queue;
+} QemuDsaDevice;
+
+typedef struct {
+ QemuDsaDevice *dsa_devices;
+ int num_dsa_devices;
+ /* The index of the next DSA device to be used. */
+ uint32_t device_allocator_index;
+ bool running;
+ QemuMutex task_queue_lock;
+ QemuCond task_queue_cond;
+ dsa_task_queue task_queue;
+} QemuDsaDeviceGroup;
+
+uint64_t max_retry_count;
+static QemuDsaDeviceGroup dsa_group;
+
+
+/**
+ * @brief This function opens a DSA device's work queue and
+ * maps the DSA device memory into the current process.
+ *
+ * @param dsa_wq_path A pointer to the DSA device work queue's file path.
+ * @return A pointer to the mapped memory, or MAP_FAILED on failure.
+ */
+static void *
+map_dsa_device(const char *dsa_wq_path)
+{
+ void *dsa_device;
+ int fd;
+
+ fd = open(dsa_wq_path, O_RDWR);
+ if (fd < 0) {
+ error_report("Open %s failed with errno = %d.",
+ dsa_wq_path, errno);
+ return MAP_FAILED;
+ }
+ dsa_device = mmap(NULL, DSA_WQ_SIZE, PROT_WRITE,
+ MAP_SHARED | MAP_POPULATE, fd, 0);
+ close(fd);
+ if (dsa_device == MAP_FAILED) {
+ error_report("mmap failed with errno = %d.", errno);
+ return MAP_FAILED;
+ }
+ return dsa_device;
+}
+
+/**
+ * @brief Initializes a DSA device structure.
+ *
+ * @param instance A pointer to the DSA device.
+ * @param work_queue A pointer to the DSA work queue.
+ */
+static void
+dsa_device_init(QemuDsaDevice *instance,
+ void *dsa_work_queue)
+{
+ instance->work_queue = dsa_work_queue;
+}
+
+/**
+ * @brief Cleans up a DSA device structure.
+ *
+ * @param instance A pointer to the DSA device to cleanup.
+ */
+static void
+dsa_device_cleanup(QemuDsaDevice *instance)
+{
+ if (instance->work_queue != MAP_FAILED) {
+ munmap(instance->work_queue, DSA_WQ_SIZE);
+ }
+}
+
+/**
+ * @brief Initializes a DSA device group.
+ *
+ * @param group A pointer to the DSA device group.
+ * @param dsa_parameter A list of DSA device path from are separated by space
+ * character migration parameter. Multiple DSA device path.
+ *
+ * @return Zero if successful, non-zero otherwise.
+ */
+static int
+dsa_device_group_init(QemuDsaDeviceGroup *group,
+ const char *dsa_parameter,
+ Error **errp)
+{
+ if (dsa_parameter == NULL || strlen(dsa_parameter) == 0) {
+ return 0;
+ }
+
+ int ret = 0;
+ char *local_dsa_parameter = g_strdup(dsa_parameter);
+ const char *dsa_path[MAX_DSA_DEVICES];
+ int num_dsa_devices = 0;
+ char delim[2] = " ";
+
+ char *current_dsa_path = strtok(local_dsa_parameter, delim);
+
+ while (current_dsa_path != NULL) {
+ dsa_path[num_dsa_devices++] = current_dsa_path;
+ if (num_dsa_devices == MAX_DSA_DEVICES) {
+ break;
+ }
+ current_dsa_path = strtok(NULL, delim);
+ }
+
+ group->dsa_devices =
+ g_new0(QemuDsaDevice, num_dsa_devices);
+ group->num_dsa_devices = num_dsa_devices;
+ group->device_allocator_index = 0;
+
+ group->running = false;
+ qemu_mutex_init(&group->task_queue_lock);
+ qemu_cond_init(&group->task_queue_cond);
+ QSIMPLEQ_INIT(&group->task_queue);
+
+ void *dsa_wq = MAP_FAILED;
+ for (int i = 0; i < num_dsa_devices; i++) {
+ dsa_wq = map_dsa_device(dsa_path[i]);
+ if (dsa_wq == MAP_FAILED) {
+ error_setg(errp, "map_dsa_device failed MAP_FAILED.");
+ ret = -1;
+ goto exit;
+ }
+ dsa_device_init(&dsa_group.dsa_devices[i], dsa_wq);
+ }
+
+exit:
+ g_free(local_dsa_parameter);
+ return ret;
+}
+
+/**
+ * @brief Starts a DSA device group.
+ *
+ * @param group A pointer to the DSA device group.
+ */
+static void
+dsa_device_group_start(QemuDsaDeviceGroup *group)
+{
+ group->running = true;
+}
+
+/**
+ * @brief Stops a DSA device group.
+ *
+ * @param group A pointer to the DSA device group.
+ */
+__attribute__((unused))
+static void
+dsa_device_group_stop(QemuDsaDeviceGroup *group)
+{
+ group->running = false;
+}
+
+/**
+ * @brief Cleans up a DSA device group.
+ *
+ * @param group A pointer to the DSA device group.
+ */
+static void
+dsa_device_group_cleanup(QemuDsaDeviceGroup *group)
+{
+ if (!group->dsa_devices) {
+ return;
+ }
+ for (int i = 0; i < group->num_dsa_devices; i++) {
+ dsa_device_cleanup(&group->dsa_devices[i]);
+ }
+ g_free(group->dsa_devices);
+ group->dsa_devices = NULL;
+
+ qemu_mutex_destroy(&group->task_queue_lock);
+ qemu_cond_destroy(&group->task_queue_cond);
+}
+
+/**
+ * @brief Returns the next available DSA device in the group.
+ *
+ * @param group A pointer to the DSA device group.
+ *
+ * @return struct QemuDsaDevice* A pointer to the next available DSA device
+ * in the group.
+ */
+__attribute__((unused))
+static QemuDsaDevice *
+dsa_device_group_get_next_device(QemuDsaDeviceGroup *group)
+{
+ if (group->num_dsa_devices == 0) {
+ return NULL;
+ }
+ uint32_t current = qatomic_fetch_inc(&group->device_allocator_index);
+ current %= group->num_dsa_devices;
+ return &group->dsa_devices[current];
+}
+
+/**
+ * @brief Check if DSA is running.
+ *
+ * @return True if DSA is running, otherwise false.
+ */
+bool qemu_dsa_is_running(void)
+{
+ return false;
+}
+
+static void
+dsa_globals_init(void)
+{
+ max_retry_count = UINT64_MAX;
+}
+
+/**
+ * @brief Initializes DSA devices.
+ *
+ * @param dsa_parameter A list of DSA device path from migration parameter.
+ *
+ * @return int Zero if successful, otherwise non zero.
+ */
+int qemu_dsa_init(const char *dsa_parameter, Error **errp)
+{
+ dsa_globals_init();
+
+ return dsa_device_group_init(&dsa_group, dsa_parameter, errp);
+}
+
+/**
+ * @brief Start logic to enable using DSA.
+ *
+ */
+void qemu_dsa_start(void)
+{
+ if (dsa_group.num_dsa_devices == 0) {
+ return;
+ }
+ if (dsa_group.running) {
+ return;
+ }
+ dsa_device_group_start(&dsa_group);
+}
+
+/**
+ * @brief Stop the device group and the completion thread.
+ *
+ */
+void qemu_dsa_stop(void)
+{
+ QemuDsaDeviceGroup *group = &dsa_group;
+
+ if (!group->running) {
+ return;
+ }
+}
+
+/**
+ * @brief Clean up system resources created for DSA offloading.
+ *
+ */
+void qemu_dsa_cleanup(void)
+{
+ qemu_dsa_stop();
+ dsa_device_group_cleanup(&dsa_group);
+}
+
diff --git a/util/meson.build b/util/meson.build
index 5d8bef9891..3360f62923 100644
--- a/util/meson.build
+++ b/util/meson.build
@@ -88,6 +88,9 @@ if have_block or have_ga
endif
if have_block
util_ss.add(files('aio-wait.c'))
+ if config_host_data.get('CONFIG_DSA_OPT')
+ util_ss.add(files('dsa.c'))
+ endif
util_ss.add(files('buffer.c'))
util_ss.add(files('bufferiszero.c'))
util_ss.add(files('hbitmap.c'))
--
Yichen Wang
