qemu-devel.nongnu.org archive mirror
 help / color / mirror / Atom feed
From: Orit Wasserman <owasserm@redhat.com>
To: qemu-devel@nongnu.org
Cc: mst@redhat.com, quintela@redhat.com,
	Orit Wasserman <owasserm@redhat.com>,
	pbonzini@redhat.com, chegu_vinod@hp.com
Subject: [Qemu-devel] [PATCH v5 6/7] Add qemu_put_buffer_async
Date: Fri, 22 Mar 2013 16:48:02 +0200	[thread overview]
Message-ID: <1363963683-26157-7-git-send-email-owasserm@redhat.com> (raw)
In-Reply-To: <1363963683-26157-1-git-send-email-owasserm@redhat.com>

This allows us to add a buffer to the iovec to send without copying it
into the static buffer, the buffer will be sent later when qemu_fflush is called.

Signed-off-by: Orit Wasserman <owasserm@redhat.com>
---
 include/migration/qemu-file.h |  5 +++++
 savevm.c                      | 34 ++++++++++++++++++++++++++--------
 2 files changed, 31 insertions(+), 8 deletions(-)

diff --git a/include/migration/qemu-file.h b/include/migration/qemu-file.h
index 8b8070f..623c434 100644
--- a/include/migration/qemu-file.h
+++ b/include/migration/qemu-file.h
@@ -75,6 +75,11 @@ int qemu_fclose(QEMUFile *f);
 int64_t qemu_ftell(QEMUFile *f);
 void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, int size);
 void qemu_put_byte(QEMUFile *f, int v);
+/*
+ * put_buffer without copying the buffer.
+ * The buffer should be available till it is sent asynchronously.
+ */
+void qemu_put_buffer_async(QEMUFile *f, const uint8_t *buf, int size);
 
 static inline void qemu_put_ubyte(QEMUFile *f, unsigned int v)
 {
diff --git a/savevm.c b/savevm.c
index 294434b..63ab79b 100644
--- a/savevm.c
+++ b/savevm.c
@@ -633,6 +633,28 @@ static void add_to_iovec(QEMUFile *f, const uint8_t *buf, int size)
     }
 }
 
+void qemu_put_buffer_async(QEMUFile *f, const uint8_t *buf, int size)
+{
+    if (f->last_error) {
+        return;
+    }
+
+    if (f->is_write == 0 && f->buf_index > 0) {
+        fprintf(stderr,
+                "Attempted to write to buffer while read buffer is not empty\n");
+        abort();
+    }
+
+    add_to_iovec(f, buf, size);
+
+    f->is_write = 1;
+    f->bytes_xfer += size;
+
+    if (f->buf_index >= IO_BUF_SIZE || f->iovcnt >= MAX_IOV_SIZE) {
+        qemu_fflush(f);
+    }
+}
+
 void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, int size)
 {
     int l;
@@ -652,18 +674,14 @@ void qemu_put_buffer(QEMUFile *f, const uint8_t *buf, int size)
         if (l > size)
             l = size;
         memcpy(f->buf + f->buf_index, buf, l);
-        add_to_iovec(f, f->buf + f->buf_index, l);
         f->is_write = 1;
         f->buf_index += l;
-        f->bytes_xfer += l;
+        qemu_put_buffer_async(f, f->buf + (f->buf_index - l), l);
+        if (qemu_file_get_error(f)) {
+            break;
+        }
         buf += l;
         size -= l;
-        if (f->buf_index >= IO_BUF_SIZE || f->iovcnt >= MAX_IOV_SIZE) {
-            qemu_fflush(f);
-            if (qemu_file_get_error(f)) {
-                break;
-            }
-        }
     }
 }
 
-- 
1.7.11.7

  parent reply	other threads:[~2013-03-22 14:47 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-03-22 14:47 [Qemu-devel] [PATCH v5 0/7] Migration: Remove copying of guest ram pages Orit Wasserman
2013-03-22 14:47 ` [Qemu-devel] [PATCH v5 1/7] Add QemuFileWritevBuffer QemuFileOps Orit Wasserman
2013-03-22 14:47 ` [Qemu-devel] [PATCH v5 2/7] Add socket_writev_buffer function Orit Wasserman
2013-03-22 14:47 ` [Qemu-devel] [PATCH v5 3/7] Update bytes_xfer in qemu_put_byte Orit Wasserman
2013-03-22 14:48 ` [Qemu-devel] [PATCH v5 4/7] Store the data to send also in iovec Orit Wasserman
2013-03-22 14:48 ` [Qemu-devel] [PATCH v5 5/7] Use writev ops if available Orit Wasserman
2013-03-22 14:48 ` Orit Wasserman [this message]
2013-03-22 14:48 ` [Qemu-devel] [PATCH v5 7/7] Use qemu_put_buffer_async for guest memory pages Orit Wasserman
2013-04-05 13:44   ` Kevin Wolf
2013-04-05 15:23     ` Paolo Bonzini
2013-04-05 15:39       ` Kevin Wolf
2013-04-05 15:42         ` Paolo Bonzini
2013-04-05 15:56           ` Kevin Wolf
2013-03-27 21:27 ` [Qemu-devel] [PATCH v5 0/7] Migration: Remove copying of guest ram pages Eric Blake

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1363963683-26157-7-git-send-email-owasserm@redhat.com \
    --to=owasserm@redhat.com \
    --cc=chegu_vinod@hp.com \
    --cc=mst@redhat.com \
    --cc=pbonzini@redhat.com \
    --cc=qemu-devel@nongnu.org \
    --cc=quintela@redhat.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).