9:17 a.m.
On 7/14/21 2:28 PM, Yang Fei wrote:
Add helper function virGetCpuHaltPollTime and virGetDebugFsKvmValue
to obtain the halt polling time. If system mount debugfs, and the
kernel support halt polling time statistic, it will work.
Signed-off-by: Yang Fei <yangfei85(a)huawei.com>
---
src/libvirt_private.syms | 2 ++
src/util/virutil.c | 78 ++++++++++++++++++++++++++++++++++++++++
src/util/virutil.h | 9 +++++
3 files changed, 89 insertions(+)
diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index 68e4b6aab8..f92213b8c2 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -3479,6 +3479,8 @@ virDoesUserExist;
virDoubleToStr;
virFormatIntDecimal;
virFormatIntPretty;
+virGetCpuHaltPollTime;
+virGetDebugFsKvmValue;
virGetDeviceID;
virGetDeviceUnprivSGIO;
virGetGroupID;
diff --git a/src/util/virutil.c b/src/util/virutil.c
index c0d25fe247..7e4531b4b4 100644
--- a/src/util/virutil.c
+++ b/src/util/virutil.c
@@ -1959,3 +1959,81 @@ virGetValueRaw(const char *path,
return 0;
}
+
+int
+virGetDebugFsKvmValue(struct dirent *ent,
+ const char *path,
+ const char *filename,
+ unsigned long long *value)
+{
+ g_autofree char *valToStr = NULL;
+ g_autofree char *valPath = NULL;
+
+ valPath = g_strdup_printf("%s/%s/%s", path, ent->d_name, filename);
+
+ if (virGetValueRaw(valPath, &valToStr) < 0) {
+ return -1;
+ }
+
+ /* 10 is a Cardinality, must be between 2 and 36 inclusive,
+ * or special value 0. Used in fuction strtoull()
+ */
+ if (virStrToLong_ull(valToStr, NULL, 10, value) < 0) {
+ virReportError(VIR_ERR_INTERNAL_ERROR,
+ _("Unable to parse '%s' as an integer"),
valToStr);
+ return -1;
+ }
+
+ return 0;
+}
This looks very close to what virFileReadValueUllong() does.
+
+int
+virGetCpuHaltPollTime(pid_t pid,
+ unsigned long long *haltPollSuccess,
+ unsigned long long *haltPollFail)
+{
+ g_autofree char *pidToStr = NULL;
+ g_autofree char *debugFsPath = NULL;
+ g_autofree char *completePath = NULL;
+ struct dirent *ent = NULL;
+ DIR *dir = NULL;
+ int ret = -1;
+ int flag = 0;
+
+ if (!(debugFsPath = virFileFindMountPoint("debugfs"))) {
+ virReportSystemError(errno, "%s",
+ _("unable to find debugfs mountpoint"));
+ return ret;
+ }
Is this something worth polluting logs with error? What if we run under
kernel that doesn't have debugfs?
+
+ completePath = g_strdup_printf("%s/%s", debugFsPath, "kvm");
+ if (virDirOpen(&dir, completePath) < 0) {
+ virReportError(VIR_ERR_INTERNAL_ERROR,
+ "%s %s", "Can not open directory",
completePath);
+ return ret;
+ }
virDirOpen() reports an error on failure. No need to rewrite it. And in
the light of previous comment maybe virDirOpenIfExists() instead?
+
+ pidToStr = g_strdup_printf("%lld%c", (unsigned long long)pid,
'-');
+ while (virDirRead(dir, &ent, NULL) > 0) {
+ if (STRPREFIX(ent->d_name, pidToStr)) {
+ flag = 1;
+ break;
+ }
+ }
+
+ if (flag == 0) {
+ virReportError(VIR_ERR_INTERNAL_ERROR,
+ _("Could not find VM(Pid %s) in '%s'"),
pidToStr, completePath);
+ goto cleanup;
+ }
Again, not big fan. What it my domain runs TCG? Also, please rename
'flag' to something more specific, e.g. "found".
+
+ if (virGetDebugFsKvmValue(ent, completePath, "halt_poll_success_ns",
haltPollSuccess) < 0 ||
+ virGetDebugFsKvmValue(ent, completePath, "halt_poll_fail_ns",
haltPollFail) < 0) {
+ goto cleanup;
+ }
+
+ ret = 0;
+cleanup:
+ closedir(dir);
Again, please make sure 'ninja test' passes. We have a syntax-check rule
that forbids direct call of closedir(). The proper way is to define dir
variable like this:
g_autoptr(DIR) dir = NULL;
+ return ret;
+}
diff --git a/src/util/virutil.h b/src/util/virutil.h
index 851b421476..00cef47208 100644
--- a/src/util/virutil.h
+++ b/src/util/virutil.h
@@ -228,3 +228,12 @@ int virPipeNonBlock(int fds[2]);
int virGetValueRaw(const char *path,
char **value);
+
+int virGetDebugFsKvmValue(struct dirent *ent,
+ const char *path,
+ const char *filename,
+ unsigned long long *value);
+
+int virGetCpuHaltPollTime(pid_t pid,
+ unsigned long long *haltPollSuccess,
+ unsigned long long *haltPollFail);
Michal