On 05/01/2011 01:57 PM, Matthias Bolte wrote:
When the session has expired then multiple threads can race while reestablishing it.
This race condition is not that critical as it requires a special usage pattern to be triggerd. It can only happen when an application doesn't
s/triggerd/triggered/
do API calls for quite some time (the session expires after 30 min inactivity) and then multiple threads doing simultaneous API calls and end up doing simultaneous calls to esxVI_EnsureSession. --- src/esx/esx_vi.c | 47 +++++++++++++++++++++++++++++++++++------------ src/esx/esx_vi.h | 4 +++- 2 files changed, 38 insertions(+), 13 deletions(-)
C code - I'm back in my element!
+++ b/src/esx/esx_vi.h @@ -185,6 +185,7 @@ int esxVI_SharedCURL_Remove(esxVI_SharedCURL *shared, esxVI_CURL *curl); */
struct _esxVI_Context { + /* All members are used read-only after esxVI_Context_Connect ... */ esxVI_CURL *curl; char *url; char *ipAddress; @@ -193,7 +194,8 @@ struct _esxVI_Context { esxVI_ServiceContent *service; esxVI_APIVersion apiVersion; esxVI_ProductVersion productVersion; - esxVI_UserSession *session; + esxVI_UserSession *session; /* ... except the session ... */ + virMutexPtr sessionLock; /* ... that is protected by this mutex */
ACK, and thanks for those comments. -- Eric Blake eblake@redhat.com +1-801-349-2682 Libvirt virtualization library http://libvirt.org