[libvirt] [PATCH 1/1] nodeinfo: Increase the num of CPU thread siblings to a larger value
Current libvirt can only handle up to 1024 thread siblings when it
reads Linux sysfs topology/thread_siblings. This isn't enough for
Linux distributions that support a large value. This patch fixes
the problem by using VIR_ALLOC()/VIR_FREE(), instead of using a
fixed-size (1024) local char array. In the meanwhile
SYSFS_THREAD_SIBLINGS_LIST_LENGTH_MAX is increased to 8192 which
should be large enough for a foreseeable future.
Signed-off-by: Wei Huang <wei(a)redhat.com>
---
src/nodeinfo.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/src/nodeinfo.c b/src/nodeinfo.c
index 34d27a6..66dc7ef 100644
--- a/src/nodeinfo.c
+++ b/src/nodeinfo.c
@@ -287,7 +287,7 @@ freebsdNodeGetMemoryStats(virNodeMemoryStatsPtr params,
# define PROCSTAT_PATH "/proc/stat"
# define MEMINFO_PATH "/proc/meminfo"
# define SYSFS_MEMORY_SHARED_PATH "/sys/kernel/mm/ksm"
-# define SYSFS_THREAD_SIBLINGS_LIST_LENGTH_MAX 1024
+# define SYSFS_THREAD_SIBLINGS_LIST_LENGTH_MAX 8192
# define LINUX_NB_CPU_STATS 4
# define LINUX_NB_MEMORY_STATS_ALL 4
@@ -345,7 +345,7 @@ virNodeCountThreadSiblings(const char *dir, unsigned int cpu)
unsigned long ret = 0;
char *path;
FILE *pathfp;
- char str[1024];
+ char *str = NULL;
size_t i;
if (virAsprintf(&path, "%s/cpu%u/topology/thread_siblings",
@@ -365,7 +365,10 @@ virNodeCountThreadSiblings(const char *dir, unsigned int cpu)
return 0;
}
- if (fgets(str, sizeof(str), pathfp) == NULL) {
+ if (VIR_ALLOC_N(str, SYSFS_THREAD_SIBLINGS_LIST_LENGTH_MAX) < 0)
+ goto cleanup;
+
+ if (fgets(str, SYSFS_THREAD_SIBLINGS_LIST_LENGTH_MAX, pathfp) == NULL) {
virReportSystemError(errno, _("cannot read from %s"), path);
goto cleanup;
}
@@ -382,6 +385,7 @@ virNodeCountThreadSiblings(const char *dir, unsigned int cpu)
}
cleanup:
+ VIR_FREE(str);
VIR_FORCE_FCLOSE(pathfp);
VIR_FREE(path);
--
1.8.3.1