Re: [libvirt] [PATCH v6 3/4] nodedev: Convert virNodeDeviceObjListPtr to use hash tables

Rather than use a forward linked list of elements, it'll be much more efficient to use a hash table to reference the elements by unique name and to perform hash searches. This patch does all the heavy lifting of converting the list object to use a self locking list that contains the hash table. Each of the FindBy functions that do not involve finding the object by it's key (name) is converted to use virHashSearch in order to find the specific object. When searching for the key (name), it's possible to use virHashLookup. For any of the list perusal functions that are required to evaluate each object, the virHashForEach function is used. Signed-off-by: John Ferlan <jferlan(a)redhat.com&gt; --- src/conf/virnodedeviceobj.c | 575 ++++++++++++++++++++++++++++++-------------- 1 file changed, 400 insertions(+), 175 deletions(-) diff --git a/src/conf/virnodedeviceobj.c b/src/conf/virnodedeviceobj.c index 035a56d..58481e7 100644 --- a/src/conf/virnodedeviceobj.c +++ b/src/conf/virnodedeviceobj.c @@ -25,6 +25,7 @@ #include "viralloc.h" #include "virnodedeviceobj.h" #include "virerror.h" +#include "virhash.h" #include "virlog.h" #include "virstring.h" @@ -39,13 +40,19 @@ struct _virNodeDeviceObj { }; struct _virNodeDeviceObjList { - size_t count; - virNodeDeviceObjPtr *objs; + virObjectLockable parent; + + /* name string -> virNodeDeviceObj mapping + * for O(1), lockless lookup-by-uuid */ + virHashTable *objs; + }; static virClassPtr virNodeDeviceObjClass; +static virClassPtr virNodeDeviceObjListClass; static void virNodeDeviceObjDispose(void *opaque); +static void virNodeDeviceObjListDispose(void *opaque); static int virNodeDeviceObjOnceInit(void) @@ -56,6 +63,12 @@ virNodeDeviceObjOnceInit(void) virNodeDeviceObjDispose))) return -1; + if (!(virNodeDeviceObjListClass = virClassNew(virClassForObjectLockable(), + "virNodeDeviceObjList", + sizeof(virNodeDeviceObjList), + virNodeDeviceObjListDispose))) + return -1; + return 0; } @@ -211,26 +224,49 @@ virNodeDeviceFindVPORTCapDef(const virNodeDeviceObj *obj) } +static int +virNodeDeviceObjListFindBySysfsPathCallback(const void *payload, + const void *name ATTRIBUTE_UNUSED, + const void *opaque) +{ + virNodeDeviceObjPtr obj = (virNodeDeviceObjPtr) payload; + virNodeDeviceDefPtr def;

+ const char *sysfs_path = opaque; + int want = 0; + + virObjectLock(obj); + def = obj->def;

virNodeDeviceObjPtr virNodeDeviceObjListFindBySysfsPath(virNodeDeviceObjListPtr devs, const char *sysfs_path) { - size_t i; + virNodeDeviceObjPtr obj; - for (i = 0; i < devs->count; i++) { - virNodeDeviceObjPtr obj = devs->objs[i]; - virNodeDeviceDefPtr def; + virObjectLock(devs); + obj = virHashSearch(devs->objs, virNodeDeviceObjListFindBySysfsPathCallback, + (void *)sysfs_path, NULL); + virObjectRef(obj); + virObjectUnlock(devs); + if (obj) virObjectLock(obj); - def = obj->def; - if ((def->sysfs_path != NULL) && - (STREQ(def->sysfs_path, sysfs_path))) { - return virObjectRef(obj); - } - virObjectUnlock(obj); - } - return NULL; + return obj;