Re: [Qemu-devel] [PATCH v5 12/17] migration: Send the fd number which we are going to use for this page

2017-08-09 Thread Paolo Bonzini
On 17/07/2017 15:42, Juan Quintela wrote:
> We are still sending the page through the main channel, that would
> change later in the series
> 
> Signed-off-by: Juan Quintela 
> ---
>  migration/ram.c | 13 +++--
>  1 file changed, 11 insertions(+), 2 deletions(-)
> 
> diff --git a/migration/ram.c b/migration/ram.c
> index 90e1bcb..ac0742f 100644
> --- a/migration/ram.c
> +++ b/migration/ram.c
> @@ -568,7 +568,7 @@ static int multifd_send_page(uint8_t *address)
>  qemu_mutex_unlock(&p->mutex);
>  qemu_sem_post(&p->sem);
>  
> -return 0;
> +return i;
>  }
>  
>  struct MultiFDRecvParams {
> @@ -1143,6 +1143,7 @@ static int ram_multifd_page(RAMState *rs, 
> PageSearchStatus *pss,
>  bool last_stage)
>  {
>  int pages;
> +uint16_t fd_num;
>  uint8_t *p;
>  RAMBlock *block = pss->block;
>  ram_addr_t offset = pss->page << TARGET_PAGE_BITS;
> @@ -1154,8 +1155,10 @@ static int ram_multifd_page(RAMState *rs, 
> PageSearchStatus *pss,
>  ram_counters.transferred +=
>  save_page_header(rs, rs->f, block,
>   offset | RAM_SAVE_FLAG_MULTIFD_PAGE);
> +fd_num = multifd_send_page(p);
> +qemu_put_be16(rs->f, fd_num);
> +ram_counters.transferred += 2; /* size of fd_num */
>  qemu_put_buffer(rs->f, p, TARGET_PAGE_SIZE);
> -multifd_send_page(p);
>  ram_counters.transferred += TARGET_PAGE_SIZE;
>  pages = 1;
>  ram_counters.normal++;
> @@ -2905,6 +2908,7 @@ static int ram_load(QEMUFile *f, void *opaque, int 
> version_id)
>  while (!postcopy_running && !ret && !(flags & RAM_SAVE_FLAG_EOS)) {
>  ram_addr_t addr, total_ram_bytes;
>  void *host = NULL;
> +uint16_t fd_num;
>  uint8_t ch;
>  
>  addr = qemu_get_be64(f);
> @@ -3015,6 +3019,11 @@ static int ram_load(QEMUFile *f, void *opaque, int 
> version_id)
>  break;
>  
>  case RAM_SAVE_FLAG_MULTIFD_PAGE:
> +fd_num = qemu_get_be16(f);
> +if (fd_num != 0) {
> +/* this is yet an unused variable, changed later */
> +fd_num = fd_num;
> +}
>  qemu_get_buffer(f, host, TARGET_PAGE_SIZE);
>  break;
>  
> 


I'm still not convinced of doing this instead of just treating all
sockets equivalently (and flushing them all when the main socket is told
that there is a new block).

Paolo



Re: [Qemu-devel] [PATCH v5 12/17] migration: Send the fd number which we are going to use for this page

2017-07-20 Thread Dr. David Alan Gilbert
* Juan Quintela (quint...@redhat.com) wrote:
> We are still sending the page through the main channel, that would
> change later in the series
> 
> Signed-off-by: Juan Quintela 
> ---
>  migration/ram.c | 13 +++--
>  1 file changed, 11 insertions(+), 2 deletions(-)
> 
> diff --git a/migration/ram.c b/migration/ram.c
> index 90e1bcb..ac0742f 100644
> --- a/migration/ram.c
> +++ b/migration/ram.c
> @@ -568,7 +568,7 @@ static int multifd_send_page(uint8_t *address)
>  qemu_mutex_unlock(&p->mutex);
>  qemu_sem_post(&p->sem);
>  
> -return 0;
> +return i;

is 'i' anything sane so far - I think this is currently a bogus value
so perhaps it's best to keep it as 0 till later?
Also, add a comment to multifd_send_page to say it'll return the fd
to use.


>  }
>  
>  struct MultiFDRecvParams {
> @@ -1143,6 +1143,7 @@ static int ram_multifd_page(RAMState *rs, 
> PageSearchStatus *pss,
>  bool last_stage)
>  {
>  int pages;
> +uint16_t fd_num;
>  uint8_t *p;
>  RAMBlock *block = pss->block;
>  ram_addr_t offset = pss->page << TARGET_PAGE_BITS;
> @@ -1154,8 +1155,10 @@ static int ram_multifd_page(RAMState *rs, 
> PageSearchStatus *pss,
>  ram_counters.transferred +=
>  save_page_header(rs, rs->f, block,
>   offset | RAM_SAVE_FLAG_MULTIFD_PAGE);
> +fd_num = multifd_send_page(p);
> +qemu_put_be16(rs->f, fd_num);

Check for errors from multifd_send_page?
(I'd have preferred to have made this one field in a new fixed size word
which will get used for other things as well, but I'm OK with it this
way).

I think you've also got a 2^8 fd limit in some of the other configs
as opposed to the 2^16 here.

> +ram_counters.transferred += 2; /* size of fd_num */
>  qemu_put_buffer(rs->f, p, TARGET_PAGE_SIZE);
> -multifd_send_page(p);
>  ram_counters.transferred += TARGET_PAGE_SIZE;
>  pages = 1;
>  ram_counters.normal++;
> @@ -2905,6 +2908,7 @@ static int ram_load(QEMUFile *f, void *opaque, int 
> version_id)
>  while (!postcopy_running && !ret && !(flags & RAM_SAVE_FLAG_EOS)) {
>  ram_addr_t addr, total_ram_bytes;
>  void *host = NULL;
> +uint16_t fd_num;
>  uint8_t ch;
>  
>  addr = qemu_get_be64(f);
> @@ -3015,6 +3019,11 @@ static int ram_load(QEMUFile *f, void *opaque, int 
> version_id)
>  break;
>  
>  case RAM_SAVE_FLAG_MULTIFD_PAGE:
> +fd_num = qemu_get_be16(f);
> +if (fd_num != 0) {
> +/* this is yet an unused variable, changed later */
> +fd_num = fd_num;
> +}
>  qemu_get_buffer(f, host, TARGET_PAGE_SIZE);
>  break;

Dave

> -- 
> 2.9.4
> 
--
Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK



[Qemu-devel] [PATCH v5 12/17] migration: Send the fd number which we are going to use for this page

2017-07-17 Thread Juan Quintela
We are still sending the page through the main channel, that would
change later in the series

Signed-off-by: Juan Quintela 
---
 migration/ram.c | 13 +++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/migration/ram.c b/migration/ram.c
index 90e1bcb..ac0742f 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -568,7 +568,7 @@ static int multifd_send_page(uint8_t *address)
 qemu_mutex_unlock(&p->mutex);
 qemu_sem_post(&p->sem);
 
-return 0;
+return i;
 }
 
 struct MultiFDRecvParams {
@@ -1143,6 +1143,7 @@ static int ram_multifd_page(RAMState *rs, 
PageSearchStatus *pss,
 bool last_stage)
 {
 int pages;
+uint16_t fd_num;
 uint8_t *p;
 RAMBlock *block = pss->block;
 ram_addr_t offset = pss->page << TARGET_PAGE_BITS;
@@ -1154,8 +1155,10 @@ static int ram_multifd_page(RAMState *rs, 
PageSearchStatus *pss,
 ram_counters.transferred +=
 save_page_header(rs, rs->f, block,
  offset | RAM_SAVE_FLAG_MULTIFD_PAGE);
+fd_num = multifd_send_page(p);
+qemu_put_be16(rs->f, fd_num);
+ram_counters.transferred += 2; /* size of fd_num */
 qemu_put_buffer(rs->f, p, TARGET_PAGE_SIZE);
-multifd_send_page(p);
 ram_counters.transferred += TARGET_PAGE_SIZE;
 pages = 1;
 ram_counters.normal++;
@@ -2905,6 +2908,7 @@ static int ram_load(QEMUFile *f, void *opaque, int 
version_id)
 while (!postcopy_running && !ret && !(flags & RAM_SAVE_FLAG_EOS)) {
 ram_addr_t addr, total_ram_bytes;
 void *host = NULL;
+uint16_t fd_num;
 uint8_t ch;
 
 addr = qemu_get_be64(f);
@@ -3015,6 +3019,11 @@ static int ram_load(QEMUFile *f, void *opaque, int 
version_id)
 break;
 
 case RAM_SAVE_FLAG_MULTIFD_PAGE:
+fd_num = qemu_get_be16(f);
+if (fd_num != 0) {
+/* this is yet an unused variable, changed later */
+fd_num = fd_num;
+}
 qemu_get_buffer(f, host, TARGET_PAGE_SIZE);
 break;
 
-- 
2.9.4