diff mbox series

[v4,2/8] migration/multifd: add get_iov_count in the multifd method

Message ID 20240304140028.1590649-3-yuan1.liu@intel.com
State New
Headers show
Series Live Migration With IAA | expand

Commit Message

Yuan Liu March 4, 2024, 2 p.m. UTC
the new function get_iov_count is used to get the number of
IOVs required by a specified multifd method

Different multifd methods may require different numbers of IOVs.
Based on streaming compression of zlib and zstd, all pages will be
compressed to a data block, so an IOV is required to send this data
block. For no compression, each IOV is used to send a page, so the
number of IOVs required is the same as the number of pages.

Signed-off-by: Yuan Liu <yuan1.liu@intel.com>
Reviewed-by: Nanhai Zou <nanhai.zou@intel.com>
---
 migration/multifd-zlib.c | 18 +++++++++++++++++-
 migration/multifd-zstd.c | 18 +++++++++++++++++-
 migration/multifd.c      | 24 +++++++++++++++++++++---
 migration/multifd.h      |  2 ++
 4 files changed, 57 insertions(+), 5 deletions(-)

Comments

Fabiano Rosas March 5, 2024, 8:24 p.m. UTC | #1
Yuan Liu <yuan1.liu@intel.com> writes:

> the new function get_iov_count is used to get the number of
> IOVs required by a specified multifd method
>
> Different multifd methods may require different numbers of IOVs.
> Based on streaming compression of zlib and zstd, all pages will be
> compressed to a data block, so an IOV is required to send this data
> block. For no compression, each IOV is used to send a page, so the
> number of IOVs required is the same as the number of pages.

Let's just move the responsibility of allocating p->iov to the client
code. You can move the allocation into send_setup() and the free into
send_cleanup().

>
> Signed-off-by: Yuan Liu <yuan1.liu@intel.com>
> Reviewed-by: Nanhai Zou <nanhai.zou@intel.com>
> ---
>  migration/multifd-zlib.c | 18 +++++++++++++++++-
>  migration/multifd-zstd.c | 18 +++++++++++++++++-
>  migration/multifd.c      | 24 +++++++++++++++++++++---
>  migration/multifd.h      |  2 ++
>  4 files changed, 57 insertions(+), 5 deletions(-)
>
> diff --git a/migration/multifd-zlib.c b/migration/multifd-zlib.c
> index 012e3bdea1..35187f2aff 100644
> --- a/migration/multifd-zlib.c
> +++ b/migration/multifd-zlib.c
> @@ -313,13 +313,29 @@ static int zlib_recv_pages(MultiFDRecvParams *p, Error **errp)
>      return 0;
>  }
>  
> +/**
> + * zlib_get_iov_count: get the count of IOVs
> + *
> + * For zlib streaming compression, all pages will be compressed into a data
> + * block, and an IOV is requested for sending this block.
> + *
> + * Returns the count of the IOVs
> + *
> + * @page_count: Indicate the maximum count of pages processed by multifd
> + */
> +static uint32_t zlib_get_iov_count(uint32_t page_count)
> +{
> +    return 1;
> +}
> +
>  static MultiFDMethods multifd_zlib_ops = {
>      .send_setup = zlib_send_setup,
>      .send_cleanup = zlib_send_cleanup,
>      .send_prepare = zlib_send_prepare,
>      .recv_setup = zlib_recv_setup,
>      .recv_cleanup = zlib_recv_cleanup,
> -    .recv_pages = zlib_recv_pages
> +    .recv_pages = zlib_recv_pages,
> +    .get_iov_count = zlib_get_iov_count
>  };
>  
>  static void multifd_zlib_register(void)
> diff --git a/migration/multifd-zstd.c b/migration/multifd-zstd.c
> index dc8fe43e94..25ed1add2a 100644
> --- a/migration/multifd-zstd.c
> +++ b/migration/multifd-zstd.c
> @@ -304,13 +304,29 @@ static int zstd_recv_pages(MultiFDRecvParams *p, Error **errp)
>      return 0;
>  }
>  
> +/**
> + * zstd_get_iov_count: get the count of IOVs
> + *
> + * For zstd streaming compression, all pages will be compressed into a data
> + * block, and an IOV is requested for sending this block.
> + *
> + * Returns the count of the IOVs
> + *
> + * @page_count: Indicate the maximum count of pages processed by multifd
> + */
> +static uint32_t zstd_get_iov_count(uint32_t page_count)
> +{
> +    return 1;
> +}
> +
>  static MultiFDMethods multifd_zstd_ops = {
>      .send_setup = zstd_send_setup,
>      .send_cleanup = zstd_send_cleanup,
>      .send_prepare = zstd_send_prepare,
>      .recv_setup = zstd_recv_setup,
>      .recv_cleanup = zstd_recv_cleanup,
> -    .recv_pages = zstd_recv_pages
> +    .recv_pages = zstd_recv_pages,
> +    .get_iov_count = zstd_get_iov_count
>  };
>  
>  static void multifd_zstd_register(void)
> diff --git a/migration/multifd.c b/migration/multifd.c
> index adfe8c9a0a..787402247e 100644
> --- a/migration/multifd.c
> +++ b/migration/multifd.c
> @@ -209,13 +209,29 @@ static int nocomp_recv_pages(MultiFDRecvParams *p, Error **errp)
>      return qio_channel_readv_all(p->c, p->iov, p->normal_num, errp);
>  }
>  
> +/**
> + * nocomp_get_iov_count: get the count of IOVs
> + *
> + * For no compression, the count of IOVs required is the same as the count of
> + * pages
> + *
> + * Returns the count of the IOVs
> + *
> + * @page_count: Indicate the maximum count of pages processed by multifd
> + */
> +static uint32_t nocomp_get_iov_count(uint32_t page_count)
> +{
> +    return page_count;
> +}
> +
>  static MultiFDMethods multifd_nocomp_ops = {
>      .send_setup = nocomp_send_setup,
>      .send_cleanup = nocomp_send_cleanup,
>      .send_prepare = nocomp_send_prepare,
>      .recv_setup = nocomp_recv_setup,
>      .recv_cleanup = nocomp_recv_cleanup,
> -    .recv_pages = nocomp_recv_pages
> +    .recv_pages = nocomp_recv_pages,
> +    .get_iov_count = nocomp_get_iov_count
>  };
>  
>  static MultiFDMethods *multifd_ops[MULTIFD_COMPRESSION__MAX] = {
> @@ -998,6 +1014,8 @@ bool multifd_send_setup(void)
>      Error *local_err = NULL;
>      int thread_count, ret = 0;
>      uint32_t page_count = MULTIFD_PACKET_SIZE / qemu_target_page_size();
> +    /* We need one extra place for the packet header */
> +    uint32_t iov_count = 1;
>      uint8_t i;
>  
>      if (!migrate_multifd()) {
> @@ -1012,6 +1030,7 @@ bool multifd_send_setup(void)
>      qemu_sem_init(&multifd_send_state->channels_ready, 0);
>      qatomic_set(&multifd_send_state->exiting, 0);
>      multifd_send_state->ops = multifd_ops[migrate_multifd_compression()];
> +    iov_count += multifd_send_state->ops->get_iov_count(page_count);
>  
>      for (i = 0; i < thread_count; i++) {
>          MultiFDSendParams *p = &multifd_send_state->params[i];
> @@ -1026,8 +1045,7 @@ bool multifd_send_setup(void)
>          p->packet->magic = cpu_to_be32(MULTIFD_MAGIC);
>          p->packet->version = cpu_to_be32(MULTIFD_VERSION);
>          p->name = g_strdup_printf("multifdsend_%d", i);
> -        /* We need one extra place for the packet header */
> -        p->iov = g_new0(struct iovec, page_count + 1);
> +        p->iov = g_new0(struct iovec, iov_count);
>          p->page_size = qemu_target_page_size();
>          p->page_count = page_count;
>          p->write_flags = 0;
> diff --git a/migration/multifd.h b/migration/multifd.h
> index 8a1cad0996..d82495c508 100644
> --- a/migration/multifd.h
> +++ b/migration/multifd.h
> @@ -201,6 +201,8 @@ typedef struct {
>      void (*recv_cleanup)(MultiFDRecvParams *p);
>      /* Read all pages */
>      int (*recv_pages)(MultiFDRecvParams *p, Error **errp);
> +    /* Get the count of required IOVs */
> +    uint32_t (*get_iov_count)(uint32_t page_count);
>  } MultiFDMethods;
>  
>  void multifd_register_ops(int method, MultiFDMethods *ops);
Yuan Liu March 6, 2024, 1:16 a.m. UTC | #2
> -----Original Message-----
> From: Fabiano Rosas <farosas@suse.de>
> Sent: Wednesday, March 6, 2024 4:24 AM
> To: Liu, Yuan1 <yuan1.liu@intel.com>; peterx@redhat.com
> Cc: qemu-devel@nongnu.org; hao.xiang@bytedance.com;
> bryan.zhang@bytedance.com; Liu, Yuan1 <yuan1.liu@intel.com>; Zou, Nanhai
> <nanhai.zou@intel.com>
> Subject: Re: [PATCH v4 2/8] migration/multifd: add get_iov_count in the
> multifd method
> 
> Yuan Liu <yuan1.liu@intel.com> writes:
> 
> > the new function get_iov_count is used to get the number of
> > IOVs required by a specified multifd method
> >
> > Different multifd methods may require different numbers of IOVs.
> > Based on streaming compression of zlib and zstd, all pages will be
> > compressed to a data block, so an IOV is required to send this data
> > block. For no compression, each IOV is used to send a page, so the
> > number of IOVs required is the same as the number of pages.
> 
> Let's just move the responsibility of allocating p->iov to the client
> code. You can move the allocation into send_setup() and the free into
> send_cleanup().

Yes, this is a good way, I will implement it in the next version

> >
> > Signed-off-by: Yuan Liu <yuan1.liu@intel.com>
> > Reviewed-by: Nanhai Zou <nanhai.zou@intel.com>
> > ---
> >  migration/multifd-zlib.c | 18 +++++++++++++++++-
> >  migration/multifd-zstd.c | 18 +++++++++++++++++-
> >  migration/multifd.c      | 24 +++++++++++++++++++++---
> >  migration/multifd.h      |  2 ++
> >  4 files changed, 57 insertions(+), 5 deletions(-)
> >
> > diff --git a/migration/multifd-zlib.c b/migration/multifd-zlib.c
> > index 012e3bdea1..35187f2aff 100644
> > --- a/migration/multifd-zlib.c
> > +++ b/migration/multifd-zlib.c
> > @@ -313,13 +313,29 @@ static int zlib_recv_pages(MultiFDRecvParams *p,
> Error **errp)
> >      return 0;
> >  }
> >
> > +/**
> > + * zlib_get_iov_count: get the count of IOVs
> > + *
> > + * For zlib streaming compression, all pages will be compressed into a
> data
> > + * block, and an IOV is requested for sending this block.
> > + *
> > + * Returns the count of the IOVs
> > + *
> > + * @page_count: Indicate the maximum count of pages processed by
> multifd
> > + */
> > +static uint32_t zlib_get_iov_count(uint32_t page_count)
> > +{
> > +    return 1;
> > +}
> > +
> >  static MultiFDMethods multifd_zlib_ops = {
> >      .send_setup = zlib_send_setup,
> >      .send_cleanup = zlib_send_cleanup,
> >      .send_prepare = zlib_send_prepare,
> >      .recv_setup = zlib_recv_setup,
> >      .recv_cleanup = zlib_recv_cleanup,
> > -    .recv_pages = zlib_recv_pages
> > +    .recv_pages = zlib_recv_pages,
> > +    .get_iov_count = zlib_get_iov_count
> >  };
> >
> >  static void multifd_zlib_register(void)
> > diff --git a/migration/multifd-zstd.c b/migration/multifd-zstd.c
> > index dc8fe43e94..25ed1add2a 100644
> > --- a/migration/multifd-zstd.c
> > +++ b/migration/multifd-zstd.c
> > @@ -304,13 +304,29 @@ static int zstd_recv_pages(MultiFDRecvParams *p,
> Error **errp)
> >      return 0;
> >  }
> >
> > +/**
> > + * zstd_get_iov_count: get the count of IOVs
> > + *
> > + * For zstd streaming compression, all pages will be compressed into a
> data
> > + * block, and an IOV is requested for sending this block.
> > + *
> > + * Returns the count of the IOVs
> > + *
> > + * @page_count: Indicate the maximum count of pages processed by
> multifd
> > + */
> > +static uint32_t zstd_get_iov_count(uint32_t page_count)
> > +{
> > +    return 1;
> > +}
> > +
> >  static MultiFDMethods multifd_zstd_ops = {
> >      .send_setup = zstd_send_setup,
> >      .send_cleanup = zstd_send_cleanup,
> >      .send_prepare = zstd_send_prepare,
> >      .recv_setup = zstd_recv_setup,
> >      .recv_cleanup = zstd_recv_cleanup,
> > -    .recv_pages = zstd_recv_pages
> > +    .recv_pages = zstd_recv_pages,
> > +    .get_iov_count = zstd_get_iov_count
> >  };
> >
> >  static void multifd_zstd_register(void)
> > diff --git a/migration/multifd.c b/migration/multifd.c
> > index adfe8c9a0a..787402247e 100644
> > --- a/migration/multifd.c
> > +++ b/migration/multifd.c
> > @@ -209,13 +209,29 @@ static int nocomp_recv_pages(MultiFDRecvParams *p,
> Error **errp)
> >      return qio_channel_readv_all(p->c, p->iov, p->normal_num, errp);
> >  }
> >
> > +/**
> > + * nocomp_get_iov_count: get the count of IOVs
> > + *
> > + * For no compression, the count of IOVs required is the same as the
> count of
> > + * pages
> > + *
> > + * Returns the count of the IOVs
> > + *
> > + * @page_count: Indicate the maximum count of pages processed by
> multifd
> > + */
> > +static uint32_t nocomp_get_iov_count(uint32_t page_count)
> > +{
> > +    return page_count;
> > +}
> > +
> >  static MultiFDMethods multifd_nocomp_ops = {
> >      .send_setup = nocomp_send_setup,
> >      .send_cleanup = nocomp_send_cleanup,
> >      .send_prepare = nocomp_send_prepare,
> >      .recv_setup = nocomp_recv_setup,
> >      .recv_cleanup = nocomp_recv_cleanup,
> > -    .recv_pages = nocomp_recv_pages
> > +    .recv_pages = nocomp_recv_pages,
> > +    .get_iov_count = nocomp_get_iov_count
> >  };
> >
> >  static MultiFDMethods *multifd_ops[MULTIFD_COMPRESSION__MAX] = {
> > @@ -998,6 +1014,8 @@ bool multifd_send_setup(void)
> >      Error *local_err = NULL;
> >      int thread_count, ret = 0;
> >      uint32_t page_count = MULTIFD_PACKET_SIZE /
> qemu_target_page_size();
> > +    /* We need one extra place for the packet header */
> > +    uint32_t iov_count = 1;
> >      uint8_t i;
> >
> >      if (!migrate_multifd()) {
> > @@ -1012,6 +1030,7 @@ bool multifd_send_setup(void)
> >      qemu_sem_init(&multifd_send_state->channels_ready, 0);
> >      qatomic_set(&multifd_send_state->exiting, 0);
> >      multifd_send_state->ops =
> multifd_ops[migrate_multifd_compression()];
> > +    iov_count += multifd_send_state->ops->get_iov_count(page_count);
> >
> >      for (i = 0; i < thread_count; i++) {
> >          MultiFDSendParams *p = &multifd_send_state->params[i];
> > @@ -1026,8 +1045,7 @@ bool multifd_send_setup(void)
> >          p->packet->magic = cpu_to_be32(MULTIFD_MAGIC);
> >          p->packet->version = cpu_to_be32(MULTIFD_VERSION);
> >          p->name = g_strdup_printf("multifdsend_%d", i);
> > -        /* We need one extra place for the packet header */
> > -        p->iov = g_new0(struct iovec, page_count + 1);
> > +        p->iov = g_new0(struct iovec, iov_count);
> >          p->page_size = qemu_target_page_size();
> >          p->page_count = page_count;
> >          p->write_flags = 0;
> > diff --git a/migration/multifd.h b/migration/multifd.h
> > index 8a1cad0996..d82495c508 100644
> > --- a/migration/multifd.h
> > +++ b/migration/multifd.h
> > @@ -201,6 +201,8 @@ typedef struct {
> >      void (*recv_cleanup)(MultiFDRecvParams *p);
> >      /* Read all pages */
> >      int (*recv_pages)(MultiFDRecvParams *p, Error **errp);
> > +    /* Get the count of required IOVs */
> > +    uint32_t (*get_iov_count)(uint32_t page_count);
> >  } MultiFDMethods;
> >
> >  void multifd_register_ops(int method, MultiFDMethods *ops);
diff mbox series

Patch

diff --git a/migration/multifd-zlib.c b/migration/multifd-zlib.c
index 012e3bdea1..35187f2aff 100644
--- a/migration/multifd-zlib.c
+++ b/migration/multifd-zlib.c
@@ -313,13 +313,29 @@  static int zlib_recv_pages(MultiFDRecvParams *p, Error **errp)
     return 0;
 }
 
+/**
+ * zlib_get_iov_count: get the count of IOVs
+ *
+ * For zlib streaming compression, all pages will be compressed into a data
+ * block, and an IOV is requested for sending this block.
+ *
+ * Returns the count of the IOVs
+ *
+ * @page_count: Indicate the maximum count of pages processed by multifd
+ */
+static uint32_t zlib_get_iov_count(uint32_t page_count)
+{
+    return 1;
+}
+
 static MultiFDMethods multifd_zlib_ops = {
     .send_setup = zlib_send_setup,
     .send_cleanup = zlib_send_cleanup,
     .send_prepare = zlib_send_prepare,
     .recv_setup = zlib_recv_setup,
     .recv_cleanup = zlib_recv_cleanup,
-    .recv_pages = zlib_recv_pages
+    .recv_pages = zlib_recv_pages,
+    .get_iov_count = zlib_get_iov_count
 };
 
 static void multifd_zlib_register(void)
diff --git a/migration/multifd-zstd.c b/migration/multifd-zstd.c
index dc8fe43e94..25ed1add2a 100644
--- a/migration/multifd-zstd.c
+++ b/migration/multifd-zstd.c
@@ -304,13 +304,29 @@  static int zstd_recv_pages(MultiFDRecvParams *p, Error **errp)
     return 0;
 }
 
+/**
+ * zstd_get_iov_count: get the count of IOVs
+ *
+ * For zstd streaming compression, all pages will be compressed into a data
+ * block, and an IOV is requested for sending this block.
+ *
+ * Returns the count of the IOVs
+ *
+ * @page_count: Indicate the maximum count of pages processed by multifd
+ */
+static uint32_t zstd_get_iov_count(uint32_t page_count)
+{
+    return 1;
+}
+
 static MultiFDMethods multifd_zstd_ops = {
     .send_setup = zstd_send_setup,
     .send_cleanup = zstd_send_cleanup,
     .send_prepare = zstd_send_prepare,
     .recv_setup = zstd_recv_setup,
     .recv_cleanup = zstd_recv_cleanup,
-    .recv_pages = zstd_recv_pages
+    .recv_pages = zstd_recv_pages,
+    .get_iov_count = zstd_get_iov_count
 };
 
 static void multifd_zstd_register(void)
diff --git a/migration/multifd.c b/migration/multifd.c
index adfe8c9a0a..787402247e 100644
--- a/migration/multifd.c
+++ b/migration/multifd.c
@@ -209,13 +209,29 @@  static int nocomp_recv_pages(MultiFDRecvParams *p, Error **errp)
     return qio_channel_readv_all(p->c, p->iov, p->normal_num, errp);
 }
 
+/**
+ * nocomp_get_iov_count: get the count of IOVs
+ *
+ * For no compression, the count of IOVs required is the same as the count of
+ * pages
+ *
+ * Returns the count of the IOVs
+ *
+ * @page_count: Indicate the maximum count of pages processed by multifd
+ */
+static uint32_t nocomp_get_iov_count(uint32_t page_count)
+{
+    return page_count;
+}
+
 static MultiFDMethods multifd_nocomp_ops = {
     .send_setup = nocomp_send_setup,
     .send_cleanup = nocomp_send_cleanup,
     .send_prepare = nocomp_send_prepare,
     .recv_setup = nocomp_recv_setup,
     .recv_cleanup = nocomp_recv_cleanup,
-    .recv_pages = nocomp_recv_pages
+    .recv_pages = nocomp_recv_pages,
+    .get_iov_count = nocomp_get_iov_count
 };
 
 static MultiFDMethods *multifd_ops[MULTIFD_COMPRESSION__MAX] = {
@@ -998,6 +1014,8 @@  bool multifd_send_setup(void)
     Error *local_err = NULL;
     int thread_count, ret = 0;
     uint32_t page_count = MULTIFD_PACKET_SIZE / qemu_target_page_size();
+    /* We need one extra place for the packet header */
+    uint32_t iov_count = 1;
     uint8_t i;
 
     if (!migrate_multifd()) {
@@ -1012,6 +1030,7 @@  bool multifd_send_setup(void)
     qemu_sem_init(&multifd_send_state->channels_ready, 0);
     qatomic_set(&multifd_send_state->exiting, 0);
     multifd_send_state->ops = multifd_ops[migrate_multifd_compression()];
+    iov_count += multifd_send_state->ops->get_iov_count(page_count);
 
     for (i = 0; i < thread_count; i++) {
         MultiFDSendParams *p = &multifd_send_state->params[i];
@@ -1026,8 +1045,7 @@  bool multifd_send_setup(void)
         p->packet->magic = cpu_to_be32(MULTIFD_MAGIC);
         p->packet->version = cpu_to_be32(MULTIFD_VERSION);
         p->name = g_strdup_printf("multifdsend_%d", i);
-        /* We need one extra place for the packet header */
-        p->iov = g_new0(struct iovec, page_count + 1);
+        p->iov = g_new0(struct iovec, iov_count);
         p->page_size = qemu_target_page_size();
         p->page_count = page_count;
         p->write_flags = 0;
diff --git a/migration/multifd.h b/migration/multifd.h
index 8a1cad0996..d82495c508 100644
--- a/migration/multifd.h
+++ b/migration/multifd.h
@@ -201,6 +201,8 @@  typedef struct {
     void (*recv_cleanup)(MultiFDRecvParams *p);
     /* Read all pages */
     int (*recv_pages)(MultiFDRecvParams *p, Error **errp);
+    /* Get the count of required IOVs */
+    uint32_t (*get_iov_count)(uint32_t page_count);
 } MultiFDMethods;
 
 void multifd_register_ops(int method, MultiFDMethods *ops);