From: Uri Lublin <uril@redhat.com>
Date: Tue, 19 May 2009 11:08:53 +0000 (+0300)
Subject: migrate.c: migrate_fd_put_buffer: Do not busyloop: stop writing if EWOULDBLOCK
X-Git-Tag: v0.10.5~13
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=3978d7b4c8fe68dc45ea40097c76017938fb0ba7;p=users%2Fdwmw2%2Fqemu.git

migrate.c: migrate_fd_put_buffer: Do not busyloop: stop writing if EWOULDBLOCK

The migration code is non-blocking, designed for live migration.

Practically migrate_fd_put_buffer busy-loops trying to write, as
on many machines EWOULDBLOCK==EAGAIN (look in include/asm-generic/errno.h).

Signed-off-by: Uri Lublin <uril@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
---

diff --git a/migration.c b/migration.c
index ee9e20e4bb..06ea795cf1 100644
--- a/migration.c
+++ b/migration.c
@@ -168,7 +168,7 @@ ssize_t migrate_fd_put_buffer(void *opaque, const void *data, size_t size)
 
     do {
         ret = s->write(s, data, size);
-    } while (ret == -1 && ((s->get_error(s)) == EINTR || (s->get_error(s)) == EWOULDBLOCK));
+    } while (ret == -1 && ((s->get_error(s)) == EINTR));
 
     if (ret == -1)
         ret = -(s->get_error(s));