Re: [Libguestfs] [PATCH libnbd 2/3] states: Add handle h->wflags field.

There's an obvious bug in this patch in that it doesn't reset the h->wflags field in all cases. Updated patch below. I rechecked the performance measurements and they are the same after the updated patch. Rich. >From 15a687b50acecebcfd3dc6222d93e6df984b83c6 Mon Sep 17 00:00:00 2001 From: "Richard W.M. Jones" <rjones(a)redhat.com&gt; Date: Sat, 8 Jun 2019 19:12:22 +0100 Subject: [PATCH] states: Add handle h->wflags field. This field contains optimization flags (ie. MSG_MORE) which are passed through to the socket layer if it supports them. The flags are reset automatically when we move to another state. --- generator/states.c | 10 +++++++--- lib/internal.h | 1 + 2 files changed, 8 insertions(+), 3 deletions(-) diff --git a/generator/states.c b/generator/states.c index e879a83..b0dab83 100644 --- a/generator/states.c +++ b/generator/states.c @@ -91,8 +91,8 @@ send_from_wbuf (struct nbd_handle *h) ssize_t r; if (h->wlen == 0) - return 0; /* move to next state */ - r = h->sock->ops->send (h, h->sock, h->wbuf, h->wlen, 0); + goto next_state; + r = h->sock->ops->send (h, h->sock, h->wbuf, h->wlen, h->wflags); if (r == -1) { if (errno == EAGAIN || errno == EWOULDBLOCK) return 1; /* more data */ @@ -102,9 +102,13 @@ send_from_wbuf (struct nbd_handle *h) h->wbuf += r; h->wlen -= r; if (h->wlen == 0) - return 0; /* move to next state */ + goto next_state; else return 1; /* more data */

+ + next_state: + h->wflags = 0; /* reset this when moving to next state */ + return 0; /* move to next state */ } /*----- End of prologue. -----*/ diff --git a/lib/internal.h b/lib/internal.h index 1ffb5b7..e7be05b 100644 --- a/lib/internal.h +++ b/lib/internal.h @@ -110,6 +110,7 @@ struct nbd_handle { /* As above, but for writing using send_from_wbuf. */ const void *wbuf; size_t wlen; + int wflags; /* Static buffer used for short amounts of data, such as handshake * and commands.