0605-libxl-do-not-wait-for-backend-on-PCI-remove-when-bac.patch

From 6f2e64671cd1dc2c82bcd8574b449ed2798b0401 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marek=20Marczykowski-G=C3=B3recki?=
 <marmarek@invisiblethingslab.com>
Date: Wed, 5 Mar 2014 02:18:52 +0100
Subject: [PATCH 05/26] libxl: do not wait for backend on PCI remove when
 backend already closed
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Especially this is the case during domain destroy - backend and frontend
are already closed so just remove the devices, without waiting for
(timeout on) backend state.

Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
---
 tools/libs/light/libxl_pci.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/tools/libs/light/libxl_pci.c b/tools/libs/light/libxl_pci.c
index f4c4f175454d..b863da2f0d60 100644
--- a/tools/libs/light/libxl_pci.c
+++ b/tools/libs/light/libxl_pci.c
@@ -226,7 +226,7 @@ out:
 static int libxl__device_pci_remove_xenstore(libxl__gc *gc, uint32_t domid, libxl_device_pci *pci)
 {
     libxl_ctx *ctx = libxl__gc_owner(gc);
-    char *be_path, *num_devs_path, *num_devs, *xsdev, *tmp, *tmppath;
+    char *be_path, *num_devs_path, *num_devs, *xsdev, *tmp, *tmppath, *state_before;
     int num, i, j;
     xs_transaction_t t;
 
@@ -237,12 +237,13 @@ static int libxl__device_pci_remove_xenstore(libxl__gc *gc, uint32_t domid, libx
     if (!num_devs)
         return ERROR_INVAL;
     num = atoi(num_devs);
+    state_before = libxl__xs_read(gc, XBT_NULL, libxl__sprintf(gc, "%s/state", be_path));
 
     libxl_domain_type domtype = libxl__domain_type(gc, domid);
     if (domtype == LIBXL_DOMAIN_TYPE_INVALID)
         return ERROR_FAIL;
 
-    if (domtype == LIBXL_DOMAIN_TYPE_PV) {
+    if (domtype == LIBXL_DOMAIN_TYPE_PV && state_before && atoi(state_before) != 6) {
         if (libxl__wait_for_backend(gc, be_path, GCSPRINTF("%d", XenbusStateConnected)) < 0) {
             LOGD(DEBUG, domid, "pci backend at %s is not ready", be_path);
             return ERROR_FAIL;
@@ -264,6 +265,8 @@ static int libxl__device_pci_remove_xenstore(libxl__gc *gc, uint32_t domid, libx
     }
 
 retry_transaction:
+    if (state_before && atoi(state_before) == XenbusStateClosed)
+        goto retry_transaction2;
     t = xs_transaction_start(ctx->xsh);
     xs_write(ctx->xsh, t, GCSPRINTF("%s/state-%d", be_path, i), GCSPRINTF("%d", XenbusStateClosing), 1);
     xs_write(ctx->xsh, t, GCSPRINTF("%s/state", be_path), GCSPRINTF("%d", XenbusStateReconfiguring), 1);
-- 
2.37.3