| Message ID | 20240425022117.4035031-10-hao.xiang@linux.dev (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Use Intel DSA accelerator to offload zero page checking in multifd live migration. | expand |
On Thu, Apr 25, 2024 at 02:21:12AM +0000, Hao Xiang wrote: > 1. Refactor multifd_send_thread function. > 2. Introduce the batch task structure in MultiFDSendParams. > > Signed-off-by: Hao Xiang <hao.xiang@linux.dev> > --- > include/qemu/dsa.h | 51 +++++++++++++++++++++++++++++++++++++++++++-- > migration/multifd.c | 5 +++++ > migration/multifd.h | 2 ++ > util/dsa.c | 51 ++++++++++++++++++++++++++++++++++++++------- > 4 files changed, 99 insertions(+), 10 deletions(-) > > diff --git a/include/qemu/dsa.h b/include/qemu/dsa.h > index e002652879..0c36e93016 100644 > --- a/include/qemu/dsa.h > +++ b/include/qemu/dsa.h > @@ -2,6 +2,7 @@ > #define QEMU_DSA_H > > #include "qemu/error-report.h" > +#include "exec/cpu-common.h" > #include "qemu/thread.h" > #include "qemu/queue.h" > > @@ -42,6 +43,21 @@ typedef struct dsa_batch_task { > QSIMPLEQ_ENTRY(dsa_batch_task) entry; > } dsa_batch_task; > > +#endif > + > +struct batch_task { > +#ifdef CONFIG_DSA_OPT > + /* Address of each pages in pages */ > + ram_addr_t *addr; > + /* Zero page checking results */ > + bool *results; > + /* Batch task DSA specific implementation */ > + struct dsa_batch_task *dsa_batch; > +#endif > +}; > + > +#ifdef CONFIG_DSA_OPT > + > /** > * @brief Initializes DSA devices. > * > @@ -74,7 +90,7 @@ void dsa_cleanup(void); > bool dsa_is_running(void); > > /** > - * @brief Initializes a buffer zero batch task. > + * @brief Initializes a buffer zero DSA batch task. > * > * @param task A pointer to the batch task to initialize. > * @param results A pointer to an array of zero page checking results. > @@ -102,9 +118,26 @@ void buffer_zero_batch_task_destroy(struct dsa_batch_task *task); > * @return Zero if successful, otherwise non-zero. > */ > int > -buffer_is_zero_dsa_batch_async(struct dsa_batch_task *batch_task, > +buffer_is_zero_dsa_batch_async(struct batch_task *batch_task, > const void **buf, size_t count, size_t len); > > +/** > + * @brief Initializes a general buffer zero batch task. > + * > + * @param batch_size The number of zero page checking tasks in the batch. > + * @return A pointer to the general batch task initialized. > + */ > +struct batch_task * > +batch_task_init(int batch_size); > + > +/** > + * @brief Destroys a general buffer zero batch task. > + * > + * @param task A pointer to the general batch task to destroy. > + */ > +void > +batch_task_destroy(struct batch_task *task); > + > #else > > static inline bool dsa_is_running(void) > @@ -128,6 +161,20 @@ static inline void dsa_stop(void) {} > > static inline void dsa_cleanup(void) {} > > +static inline int > +buffer_is_zero_dsa_batch_async(struct batch_task *batch_task, > + const void **buf, size_t count, size_t len) > +{ > + exit(1); > +} > + > +static inline struct batch_task *batch_task_init(int batch_size) > +{ > + return NULL; > +} > + > +static inline void batch_task_destroy(struct batch_task *task) {} I feel like there're too many things exported for DSA. For example, at least buffer_is_zero_dsa_batch_async() looks like not needed to be exported, maybe what should be exported is zero_page_detect_dsa()? We also should avoid accessing dsa internal fields in multifd*.c generic code, for example, I think we should avoid things like below: MultiFDSendParams: struct batch_task *batch_task; multifd_send_setup: if (dsa_init(dsa_parameter)) { error_setg(&local_err, "multifd: Sender failed to initialize DSA."); error_report_err(local_err); return false; } dsa_start(); ... for (each_thread) p->batch_task = batch_task_init(page_count); This is way too ugly... We should have one multifd_dsa_send_setup() and call it once and for all, internally you can do whatever you want, rewalk the thread pool and init states. The name "batch_task" isn't clear either on being consumed by DSA. I'd think something like "dsa_state" better. So instead of above like: struct batch_task { #ifdef CONFIG_DSA_OPT /* Address of each pages in pages */ ram_addr_t *addr; /* Zero page checking results */ bool *results; /* Batch task DSA specific implementation */ struct dsa_batch_task *dsa_batch; #endif }; The fields should always be defined (say, dsa_state), then: struct dsa_state { /* Address of each pages in pages */ ram_addr_t *addr; /* Zero page checking results */ bool *results; /* Batch task DSA specific implementation */ struct dsa_batch_task *dsa_batch; }; MultiFDSendParams: ... #ifdef CONFIG_DSA_OPT struct dsa_state *dsa_state; #endif > + > #endif > > #endif > diff --git a/migration/multifd.c b/migration/multifd.c > index f317bff077..cfd3a92f6c 100644 > --- a/migration/multifd.c > +++ b/migration/multifd.c > @@ -13,6 +13,8 @@ > #include "qemu/osdep.h" > #include "qemu/cutils.h" > #include "qemu/rcu.h" > +#include "qemu/dsa.h" > +#include "qemu/memalign.h" > #include "exec/target_page.h" > #include "sysemu/sysemu.h" > #include "exec/ramblock.h" > @@ -780,6 +782,8 @@ static bool multifd_send_cleanup_channel(MultiFDSendParams *p, Error **errp) > p->name = NULL; > multifd_pages_clear(p->pages); > p->pages = NULL; > + batch_task_destroy(p->batch_task); > + p->batch_task = NULL; Again, please try to export as less DSA relevant functions as possible. Here IMHO we only need one dsa_state_destroy() on multifd_send_state, do whatever inside. > p->packet_len = 0; > g_free(p->packet); > p->packet = NULL; > @@ -1172,6 +1176,7 @@ bool multifd_send_setup(void) > qemu_sem_init(&p->sem_sync, 0); > p->id = i; > p->pages = multifd_pages_init(page_count); > + p->batch_task = batch_task_init(page_count); > > if (use_packets) { > p->packet_len = sizeof(MultiFDPacket_t) > diff --git a/migration/multifd.h b/migration/multifd.h > index c9d9b09239..16e27db5e9 100644 > --- a/migration/multifd.h > +++ b/migration/multifd.h > @@ -135,6 +135,8 @@ typedef struct { > * pending_job != 0 -> multifd_channel can use it. > */ > MultiFDPages_t *pages; > + /* Zero page checking batch task */ > + struct batch_task *batch_task; > > /* thread local variables. No locking required */ > > diff --git a/util/dsa.c b/util/dsa.c > index 5a2bf33651..4f695e58af 100644 > --- a/util/dsa.c > +++ b/util/dsa.c > @@ -802,7 +802,7 @@ buffer_zero_task_init_int(struct dsa_hw_desc *descriptor, > } > > /** > - * @brief Initializes a buffer zero batch task. > + * @brief Initializes a buffer zero DSA batch task. > * > * @param task A pointer to the batch task to initialize. > * @param results A pointer to an array of zero page checking results. > @@ -1107,29 +1107,64 @@ void dsa_cleanup(void) > * @return Zero if successful, otherwise non-zero. > */ > int > -buffer_is_zero_dsa_batch_async(struct dsa_batch_task *batch_task, > +buffer_is_zero_dsa_batch_async(struct batch_task *batch_task, > const void **buf, size_t count, size_t len) > { > - if (count <= 0 || count > batch_task->batch_size) { > + struct dsa_batch_task *dsa_batch = batch_task->dsa_batch; > + > + if (count <= 0 || count > dsa_batch->batch_size) { > return -1; > } > > - assert(batch_task != NULL); > + assert(dsa_batch != NULL); > assert(len != 0); > assert(buf != NULL); > > if (count == 1) { > /* DSA doesn't take batch operation with only 1 task. */ > - buffer_zero_dsa_async(batch_task, buf[0], len); > + buffer_zero_dsa_async(dsa_batch, buf[0], len); > } else { > - buffer_zero_dsa_batch_async(batch_task, buf, count, len); > + buffer_zero_dsa_batch_async(dsa_batch, buf, count, len); > } > > - buffer_zero_dsa_wait(batch_task); > - buffer_zero_cpu_fallback(batch_task); > + buffer_zero_dsa_wait(dsa_batch); > + buffer_zero_cpu_fallback(dsa_batch); > > return 0; > } > > +/** > + * @brief Initializes a general buffer zero batch task. > + * > + * @param batch_size The number of zero page checking tasks in the batch. > + * @return A pointer to the general batch task initialized. > + */ > +struct batch_task * > +batch_task_init(int batch_size) > +{ > + struct batch_task *task = g_malloc0(sizeof(struct batch_task)); > + task->addr = g_new0(ram_addr_t, batch_size); > + task->results = g_new0(bool, batch_size); > + task->dsa_batch = qemu_memalign(64, sizeof(struct dsa_batch_task)); > + buffer_zero_batch_task_init(task->dsa_batch, task->results, batch_size); > + > + return task; > +} > + > +/** > + * @brief Destroys a general buffer zero batch task. > + * > + * @param task A pointer to the general batch task to destroy. > + */ > +void > +batch_task_destroy(struct batch_task *task) > +{ > + g_free(task->addr); > + g_free(task->results); > + buffer_zero_batch_task_destroy(task->dsa_batch); > + qemu_vfree(task->dsa_batch); > + g_free(task); > +} > + > #endif > > -- > 2.30.2 > >
diff --git a/include/qemu/dsa.h b/include/qemu/dsa.h index e002652879..0c36e93016 100644 --- a/include/qemu/dsa.h +++ b/include/qemu/dsa.h @@ -2,6 +2,7 @@ #define QEMU_DSA_H #include "qemu/error-report.h" +#include "exec/cpu-common.h" #include "qemu/thread.h" #include "qemu/queue.h" @@ -42,6 +43,21 @@ typedef struct dsa_batch_task { QSIMPLEQ_ENTRY(dsa_batch_task) entry; } dsa_batch_task; +#endif + +struct batch_task { +#ifdef CONFIG_DSA_OPT + /* Address of each pages in pages */ + ram_addr_t *addr; + /* Zero page checking results */ + bool *results; + /* Batch task DSA specific implementation */ + struct dsa_batch_task *dsa_batch; +#endif +}; + +#ifdef CONFIG_DSA_OPT + /** * @brief Initializes DSA devices. * @@ -74,7 +90,7 @@ void dsa_cleanup(void); bool dsa_is_running(void); /** - * @brief Initializes a buffer zero batch task. + * @brief Initializes a buffer zero DSA batch task. * * @param task A pointer to the batch task to initialize. * @param results A pointer to an array of zero page checking results. @@ -102,9 +118,26 @@ void buffer_zero_batch_task_destroy(struct dsa_batch_task *task); * @return Zero if successful, otherwise non-zero. */ int -buffer_is_zero_dsa_batch_async(struct dsa_batch_task *batch_task, +buffer_is_zero_dsa_batch_async(struct batch_task *batch_task, const void **buf, size_t count, size_t len); +/** + * @brief Initializes a general buffer zero batch task. + * + * @param batch_size The number of zero page checking tasks in the batch. + * @return A pointer to the general batch task initialized. + */ +struct batch_task * +batch_task_init(int batch_size); + +/** + * @brief Destroys a general buffer zero batch task. + * + * @param task A pointer to the general batch task to destroy. + */ +void +batch_task_destroy(struct batch_task *task); + #else static inline bool dsa_is_running(void) @@ -128,6 +161,20 @@ static inline void dsa_stop(void) {} static inline void dsa_cleanup(void) {} +static inline int +buffer_is_zero_dsa_batch_async(struct batch_task *batch_task, + const void **buf, size_t count, size_t len) +{ + exit(1); +} + +static inline struct batch_task *batch_task_init(int batch_size) +{ + return NULL; +} + +static inline void batch_task_destroy(struct batch_task *task) {} + #endif #endif diff --git a/migration/multifd.c b/migration/multifd.c index f317bff077..cfd3a92f6c 100644 --- a/migration/multifd.c +++ b/migration/multifd.c @@ -13,6 +13,8 @@ #include "qemu/osdep.h" #include "qemu/cutils.h" #include "qemu/rcu.h" +#include "qemu/dsa.h" +#include "qemu/memalign.h" #include "exec/target_page.h" #include "sysemu/sysemu.h" #include "exec/ramblock.h" @@ -780,6 +782,8 @@ static bool multifd_send_cleanup_channel(MultiFDSendParams *p, Error **errp) p->name = NULL; multifd_pages_clear(p->pages); p->pages = NULL; + batch_task_destroy(p->batch_task); + p->batch_task = NULL; p->packet_len = 0; g_free(p->packet); p->packet = NULL; @@ -1172,6 +1176,7 @@ bool multifd_send_setup(void) qemu_sem_init(&p->sem_sync, 0); p->id = i; p->pages = multifd_pages_init(page_count); + p->batch_task = batch_task_init(page_count); if (use_packets) { p->packet_len = sizeof(MultiFDPacket_t) diff --git a/migration/multifd.h b/migration/multifd.h index c9d9b09239..16e27db5e9 100644 --- a/migration/multifd.h +++ b/migration/multifd.h @@ -135,6 +135,8 @@ typedef struct { * pending_job != 0 -> multifd_channel can use it. */ MultiFDPages_t *pages; + /* Zero page checking batch task */ + struct batch_task *batch_task; /* thread local variables. No locking required */ diff --git a/util/dsa.c b/util/dsa.c index 5a2bf33651..4f695e58af 100644 --- a/util/dsa.c +++ b/util/dsa.c @@ -802,7 +802,7 @@ buffer_zero_task_init_int(struct dsa_hw_desc *descriptor, } /** - * @brief Initializes a buffer zero batch task. + * @brief Initializes a buffer zero DSA batch task. * * @param task A pointer to the batch task to initialize. * @param results A pointer to an array of zero page checking results. @@ -1107,29 +1107,64 @@ void dsa_cleanup(void) * @return Zero if successful, otherwise non-zero. */ int -buffer_is_zero_dsa_batch_async(struct dsa_batch_task *batch_task, +buffer_is_zero_dsa_batch_async(struct batch_task *batch_task, const void **buf, size_t count, size_t len) { - if (count <= 0 || count > batch_task->batch_size) { + struct dsa_batch_task *dsa_batch = batch_task->dsa_batch; + + if (count <= 0 || count > dsa_batch->batch_size) { return -1; } - assert(batch_task != NULL); + assert(dsa_batch != NULL); assert(len != 0); assert(buf != NULL); if (count == 1) { /* DSA doesn't take batch operation with only 1 task. */ - buffer_zero_dsa_async(batch_task, buf[0], len); + buffer_zero_dsa_async(dsa_batch, buf[0], len); } else { - buffer_zero_dsa_batch_async(batch_task, buf, count, len); + buffer_zero_dsa_batch_async(dsa_batch, buf, count, len); } - buffer_zero_dsa_wait(batch_task); - buffer_zero_cpu_fallback(batch_task); + buffer_zero_dsa_wait(dsa_batch); + buffer_zero_cpu_fallback(dsa_batch); return 0; } +/** + * @brief Initializes a general buffer zero batch task. + * + * @param batch_size The number of zero page checking tasks in the batch. + * @return A pointer to the general batch task initialized. + */ +struct batch_task * +batch_task_init(int batch_size) +{ + struct batch_task *task = g_malloc0(sizeof(struct batch_task)); + task->addr = g_new0(ram_addr_t, batch_size); + task->results = g_new0(bool, batch_size); + task->dsa_batch = qemu_memalign(64, sizeof(struct dsa_batch_task)); + buffer_zero_batch_task_init(task->dsa_batch, task->results, batch_size); + + return task; +} + +/** + * @brief Destroys a general buffer zero batch task. + * + * @param task A pointer to the general batch task to destroy. + */ +void +batch_task_destroy(struct batch_task *task) +{ + g_free(task->addr); + g_free(task->results); + buffer_zero_batch_task_destroy(task->dsa_batch); + qemu_vfree(task->dsa_batch); + g_free(task); +} + #endif
1. Refactor multifd_send_thread function. 2. Introduce the batch task structure in MultiFDSendParams. Signed-off-by: Hao Xiang <hao.xiang@linux.dev> --- include/qemu/dsa.h | 51 +++++++++++++++++++++++++++++++++++++++++++-- migration/multifd.c | 5 +++++ migration/multifd.h | 2 ++ util/dsa.c | 51 ++++++++++++++++++++++++++++++++++++++------- 4 files changed, 99 insertions(+), 10 deletions(-)