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From: Markus Armbruster <armbru@redhat.com>
To: qemu-devel@nongnu.org
Cc: amit.shah@redhat.com, quintela@redhat.com
Subject: [Qemu-devel] [PATCH] migration: Clean up use of g_poll() in socket_writev_buffer()
Date: Tue,  1 Dec 2015 14:34:14 +0100	[thread overview]
Message-ID: <1448976854-10346-1-git-send-email-armbru@redhat.com> (raw)

socket_writev_buffer() writes in a loop, using g_poll() to block.  If
g_poll() fails, it tries to write more before the file descriptor is
ready.  In theory, this could go into a tight loop.  In practice,
errors other than EINTR are really unlikely, and when they happen,
we're probably screwed anyway, so we can just as well loop.

Clean it up a bit: retry poll on EINTR, keep ignoring other errors.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
---
Let me stress once again: this is *not* a bug fix, it's cleanup!  If
you don't like it, you can safely ignore it.  We'll then mark the spot
as intentional in the Coverity dashboard.

 migration/qemu-file-unix.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/migration/qemu-file-unix.c b/migration/qemu-file-unix.c
index c503b02..6ca53e7 100644
--- a/migration/qemu-file-unix.c
+++ b/migration/qemu-file-unix.c
@@ -72,7 +72,8 @@ static ssize_t socket_writev_buffer(void *opaque, struct iovec *iov, int iovcnt,
             pfd.fd = s->fd;
             pfd.events = G_IO_OUT | G_IO_ERR;
             pfd.revents = 0;
-            g_poll(&pfd, 1 /* 1 fd */, -1 /* no timeout */);
+            TFR(err = g_poll(&pfd, 1, -1 /* no timeout */));
+            /* Errors other than EINTR intentionally ignored */
         }
      }
 
-- 
2.4.3

             reply	other threads:[~2015-12-01 13:34 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-12-01 13:34 Markus Armbruster [this message]
2015-12-01 13:39 ` [Qemu-devel] [PATCH] migration: Clean up use of g_poll() in socket_writev_buffer() Paolo Bonzini
2015-12-02  9:04 ` Juan Quintela

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