12:59 p.m.
From: "Daniel P. Berrange" <berrange(a)redhat.com>
Introduce a qemuCapsCachePtr object to provide a global cache
of capabilities for QEMU binaries. The cache auto-populates
on first request for capabilities about a binary, and will
auto-refresh if the binary has changed since a previous cache
was populated
Signed-off-by: Daniel P. Berrange <berrange(a)redhat.com>
---
src/qemu/qemu_capabilities.c | 99 ++++++++++++++++++++++++++++++++++++++++++++
src/qemu/qemu_capabilities.h | 9 ++++
2 files changed, 108 insertions(+)
diff --git a/src/qemu/qemu_capabilities.c b/src/qemu/qemu_capabilities.c
index 3b08ef8..1163dd8 100644
--- a/src/qemu/qemu_capabilities.c
+++ b/src/qemu/qemu_capabilities.c
@@ -206,6 +206,11 @@ struct _qemuCaps {
char **machineAliases;
};
+struct _qemuCapsCache {
+ virMutex lock;
+ virHashTablePtr binaries;
+};
+
static virClassPtr qemuCapsClass;
static void qemuCapsDispose(void *obj);
@@ -1940,6 +1945,10 @@ qemuCapsPtr qemuCapsNewForBinary(const char *binary)
tmp = strstr(binary, QEMU_SYSTEM_PREFIX);
if (tmp) {
tmp += strlen(QEMU_SYSTEM_PREFIX);
+
+ /* For historical compat we uses 'itanium' as arch name */
+ if (STREQ(tmp, "ia64"))
+ tmp = "itanium";
} else {
uname_normalize(&ut);
tmp = ut.machine;
@@ -2048,3 +2057,93 @@ bool qemuCapsIsValid(qemuCapsPtr caps)
return sb.st_mtime == caps->mtime;
}
+
+
+static void
+qemuCapsHashDataFree(void *payload, const void *key ATTRIBUTE_UNUSED)
+{
+ virObjectUnref(payload);
+}
+
+qemuCapsCachePtr qemuCapsCacheNew(void)
+{
+ qemuCapsCachePtr cache;
+
+ if (VIR_ALLOC(cache) < 0) {
+ virReportOOMError();
+ return NULL;
+ }
+
+ if (virMutexInit(&cache->lock) < 0) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("Unable to initialize mutex"));
+ VIR_FREE(cache);
+ return NULL;
+ }
+
+ if (!(cache->binaries = virHashCreate(10, qemuCapsHashDataFree)))
+ goto error;
+
+ return cache;
+
+error:
+ qemuCapsCacheFree(cache);
+ return NULL;
+}
+
+
+qemuCapsPtr qemuCapsCacheLookup(qemuCapsCachePtr cache, const char *binary)
+{
+ qemuCapsPtr ret = NULL;
+ virMutexLock(&cache->lock);
+ ret = virHashLookup(cache->binaries, binary);
+ if (ret &&
+ !qemuCapsIsValid(ret)) {
+ VIR_DEBUG("Cached capabilities %p no longer valid for %s",
+ ret, binary);
+ virHashRemoveEntry(cache->binaries, binary);
+ ret = NULL;
+ }
+ if (!ret) {
+ VIR_DEBUG("Creating capabilities for %s",
+ binary);
+ ret = qemuCapsNewForBinary(binary);
+ if (ret) {
+ VIR_DEBUG("Caching capabilities %p for %s",
+ ret, binary);
+ if (virHashAddEntry(cache->binaries, binary, ret) < 0) {
+ virObjectUnref(ret);
+ ret = NULL;
+ }
+ }
+ }
+ VIR_DEBUG("Returning caps %p for %s", ret, binary);
+ virObjectRef(ret);
+ virMutexUnlock(&cache->lock);
+ return ret;
+}
+
+
+qemuCapsPtr qemuCapsCacheLookupCopy(qemuCapsCachePtr cache, const char *binary)
+{
+ qemuCapsPtr caps = qemuCapsCacheLookup(cache, binary);
+ qemuCapsPtr ret;
+
+ if (!caps)
+ return NULL;
+
+ ret = qemuCapsNewCopy(caps);
+ virObjectUnref(caps);
+ return ret;
+}
+
+
+void qemuCapsCacheFree(qemuCapsCachePtr cache)
+{
+ if (!cache)
+ return;
+
+ virHashFree(cache->binaries);
+ virMutexDestroy(&cache->lock);
+ VIR_FREE(cache);
+}
diff --git a/src/qemu/qemu_capabilities.h b/src/qemu/qemu_capabilities.h
index 485c297..27ed378 100644
--- a/src/qemu/qemu_capabilities.h
+++ b/src/qemu/qemu_capabilities.h
@@ -154,6 +154,9 @@ enum qemuCapsFlags {
typedef struct _qemuCaps qemuCaps;
typedef qemuCaps *qemuCapsPtr;
+typedef struct _qemuCapsCache qemuCapsCache;
+typedef qemuCapsCache *qemuCapsCachePtr;
+
qemuCapsPtr qemuCapsNew(void);
qemuCapsPtr qemuCapsNewCopy(qemuCapsPtr caps);
qemuCapsPtr qemuCapsNewForBinary(const char *binary);
@@ -183,6 +186,12 @@ const char *qemuCapsGetCanonicalMachine(qemuCapsPtr caps,
bool qemuCapsIsValid(qemuCapsPtr caps);
+
+qemuCapsCachePtr qemuCapsCacheNew(void);
+qemuCapsPtr qemuCapsCacheLookup(qemuCapsCachePtr cache, const char *binary);
+qemuCapsPtr qemuCapsCacheLookupCopy(qemuCapsCachePtr cache, const char *binary);
+void qemuCapsCacheFree(qemuCapsCachePtr cache);
+
virCapsPtr qemuCapsInit(virCapsPtr old_caps);
int qemuCapsProbeMachineTypes(const char *binary,
--
1.7.11.4