<html><body> pushed Sharad Mishra Open Virtualization Linux Technology Center IBM <tt>"Eduardo Lima (Etrunko)" <eblima@linux.vnet.ibm.com> wrote on 08/31/2011 06:41:56 AM: > "Eduardo Lima (Etrunko)" <eblima@linux.vnet.ibm.com> </tt> <tt>> 08/31/2011 06:41 AM</tt> <tt>> > Please respond to > eblima@br.ibm.com</tt> <tt>> > To</tt> <tt>> > List for discussion and development of libvirt CIM <libvirt-cim@redhat.com></tt> <tt>> > cc</tt> <tt>> > Sharad Mishra/Beaverton/IBM@IBMUS</tt> <tt>> > Subject</tt> <tt>> > Re: [Libvirt-cim] [PATCH] (#2) Workaround to fix race condition > around libvirt init</tt> <tt>> > On 08/30/2011 02:14 PM, Sharad Mishra wrote: > > # HG changeset patch > > # User Sharad Mishra<snmishra@us.ibm.com> > > # Date 1314719316 25200 > > # Node ID c54aafd0b2c6414f91b96bc30e2f148bb78d5c59 > > # Parent 277b56b3863b5f81a3faa18aeb7b9951b963b489 > > (#2) Workaround to fix race condition around libvirt init. > > > > This patch fixes the race condition caused when mutiple > > threads try to start VMs at the same time. This patch > > also fixes the issue of incorrect mem allocation for > > VSSD property - emulator. > > > > #2: included Edurdo's patch for make_space > > took care of coding guidelines. > > > > Signed-off-by: Sharad Mishra<snmishra@us.ibm.com> > > > > diff --git a/libxkutil/misc_util.c b/libxkutil/misc_util.c > > --- a/libxkutil/misc_util.c > > +++ b/libxkutil/misc_util.c > > @@ -28,6 +28,7 @@ > > #include<stdbool.h> > > #include<stdarg.h> > > #include<unistd.h> > > +#include<pthread.h> > > #include<libvirt/libvirt.h> > > #include<libvirt/virterror.h> > > > > @@ -45,6 +46,9 @@ > > #include "misc_util.h" > > #include "cs_util.h" > > > > +static pthread_mutex_t libvirt_mutex = PTHREAD_MUTEX_INITIALIZER; > > +/* libvirt library not initialized */ > > +static int libvirt_initialized = 0; > > > > #define URI_ENV "HYPURI" > > > > @@ -114,11 +118,15 @@ > > > > CU_DEBUG("Connecting to libvirt with uri `%s'", uri); > > > > + pthread_mutex_lock(&libvirt_mutex); > > + > > if (is_read_only()) > > conn = virConnectOpenReadOnly(uri); > > else > > conn = virConnectOpen(uri); > > > > + pthread_mutex_unlock(&libvirt_mutex); > > + > > if (!conn) { > > CU_DEBUG("Unable to connect to `%s'", uri); > > return NULL; > > @@ -530,7 +538,19 @@ > > > > bool libvirt_cim_init(void) > > { > > - return virInitialize() == 0; > > + int ret = 0; > > + > > + /* double-check lock pattern used for performance reasons */ > > + if (libvirt_initialized == 0) { > > + pthread_mutex_lock(&libvirt_mutex); > > + if (libvirt_initialized == 0) { > > + ret = virInitialize(); > > + if (ret == 0) > > + libvirt_initialized = 1; > > + } > > + pthread_mutex_unlock(&libvirt_mutex); > > + } > > + return (ret == 0); > > } > > > > bool check_refs_pfx_match(const CMPIObjectPath *refa, > > diff --git a/src/Virt_VirtualSystemManagementService.c b/src/ > Virt_VirtualSystemManagementService.c > > --- a/src/Virt_VirtualSystemManagementService.c > > +++ b/src/Virt_VirtualSystemManagementService.c > > @@ -188,6 +188,24 @@ > > return 1; > > } > > > > +static bool make_space(struct virt_device **list, int cur, int new) > > +{ > > + struct virt_device *tmp; > > + > > + tmp = calloc(cur + new, sizeof(*tmp)); > > + if (tmp == NULL) > > + return false; > > + > > + if (*list) { > > + memcpy(tmp, *list, sizeof(*tmp) * cur); > > + free(*list); > > + } > > + > > + *list = tmp; > > + > > + return true; > > +} > > + > > static bool fv_set_emulator(struct domain *domain, > > const char *emu) > > { > > @@ -198,6 +216,11 @@ > > if (emu == NULL) > > return true; > > > > + if (!make_space(&domain->dev_emu, 0, 1)) { > > + CU_DEBUG("Failed to alloc disk list"); > > + return false; > > + } > > + > > cleanup_virt_device(domain->dev_emu); > > > > domain->dev_emu->type = CIM_RES_TYPE_EMU; > > @@ -1369,24 +1392,6 @@ > > return msg; > > } > > > > -static bool make_space(struct virt_device **list, int cur, int new) > > -{ > > - struct virt_device *tmp; > > - > > - tmp = calloc(cur + new, sizeof(*tmp)); > > - if (tmp == NULL) > > - return false; > > - > > - if (*list) { > > - memcpy(tmp, *list, sizeof(*tmp) * cur); > > - free(*list); > > - } > > - > > - *list = tmp; > > - > > - return true; > > -} > > - > > static char *add_device_nodup(struct virt_device *dev, > > struct virt_device *list, > > int max, > > > > +1. Tricky stuff. :) > > -- > Eduardo de Barros Lima > Software Engineer, Open Virtualization > Linux Technology Center - IBM/Brazil > eblima@br.ibm.com > </tt></body></html>