Find device-dependent disk stats file, and skip disk stats if not available.
Change-Id: I03afb85e3357dd4c2cf5effd98b194c71d77c71d
BUG=12171
TEST=unit tested
Review URL: http://codereview.chromium.org/6541007
diff --git a/Makefile b/Makefile
index 5e3ed14..032ea73 100644
--- a/Makefile
+++ b/Makefile
@@ -38,7 +38,8 @@
metrics_library_test.o
TESTCOUNTER_LIBS = -lgmock -lgtest -lbase -lrt -lpthread -lglib-2.0
-DAEMON_LDFLAGS = $(LDFLAGS) $(LDCONFIG) -lrt -lbase -lpthread -lgflags -lglib-2.0
+DAEMON_LDFLAGS = $(LDFLAGS) $(LDCONFIG) -lrt -lbase -lpthread -lgflags \
+ -lglib-2.0 -lrootdev
TESTDAEMON_LIBS = -lgmock -lgtest
TESTLIB_LIBS = -lgtest -lbase -lrt -lpthread -lglib-2.0
diff --git a/metrics_daemon.cc b/metrics_daemon.cc
index 1e15e1d..4820590 100644
--- a/metrics_daemon.cc
+++ b/metrics_daemon.cc
@@ -146,8 +146,7 @@
session_state_(kUnknownSessionState),
user_active_(false),
usemon_interval_(0),
- usemon_source_(NULL),
- diskstats_path_(NULL) {}
+ usemon_source_(NULL) {}
MetricsDaemon::~MetricsDaemon() {
DeleteFrequencyCounters();
@@ -215,7 +214,7 @@
}
void MetricsDaemon::Init(bool testing, MetricsLibraryInterface* metrics_lib,
- const char* diskstats_path) {
+ string diskstats_path) {
testing_ = testing;
DCHECK(metrics_lib != NULL);
metrics_lib_ = metrics_lib;
@@ -243,8 +242,11 @@
ConfigureCrashFrequencyReporter(kMetricUserCrashesDailyName);
ConfigureCrashFrequencyReporter(kMetricUserCrashesWeeklyName);
- diskstats_path_ = diskstats_path;
- DiskStatsReporterInit();
+ // Don't attempt to collect disk stats if there is no disk stats file.
+ if (!diskstats_path.empty()) {
+ diskstats_path_ = diskstats_path;
+ DiskStatsReporterInit();
+ }
// Don't setup D-Bus and GLib in test mode.
if (testing)
@@ -541,7 +543,7 @@
int nchars;
int nitems;
char line[200];
- int file = HANDLE_EINTR(open(diskstats_path_, O_RDONLY));
+ int file = HANDLE_EINTR(open(diskstats_path_.c_str(), O_RDONLY));
if (file < 0) {
PLOG(WARNING) << "cannot open " << diskstats_path_;
return;
diff --git a/metrics_daemon.h b/metrics_daemon.h
index dd61322..5252518 100644
--- a/metrics_daemon.h
+++ b/metrics_daemon.h
@@ -30,7 +30,7 @@
// Initializes.
void Init(bool testing, MetricsLibraryInterface* metrics_lib,
- const char* diskstats_path);
+ std::string diskstats_path);
// Does all the work. If |run_as_daemon| is true, daemonizes by
// forking.
@@ -304,7 +304,7 @@
long int write_sectors_;
DiskStatsState diskstats_state_;
- const char* diskstats_path_;
+ std::string diskstats_path_;
};
#endif // METRICS_DAEMON_H_
diff --git a/metrics_daemon_main.cc b/metrics_daemon_main.cc
index 899256c..1ee0611 100644
--- a/metrics_daemon_main.cc
+++ b/metrics_daemon_main.cc
@@ -3,20 +3,44 @@
// found in the LICENSE file.
+#include <base/logging.h>
+#include <base/string_util.h>
#include <gflags/gflags.h>
+#include <rootdev/rootdev.h>
#include "metrics_daemon.h"
DEFINE_bool(daemon, true, "run as daemon (use -nodaemon for debugging)");
-// Path to disk stats. This may be system dependent.
-const char kMetricsMainDiskStatsPath[] = "/sys/class/block/sda/stat";
+// Return the path to the disk stats in the sysfs.
+static
+const std::string MetricsMainDiskStatsPath() {
+ char dev_path_cstr[PATH_MAX];
+ std::string dev_prefix = "/dev/";
+ std::string dev_path;
+ std::string dev_name;
+
+ int ret = rootdev(dev_path_cstr, sizeof(dev_path_cstr), true, true);
+ if (ret != 0) {
+ LOG(WARNING) << "error " << ret << " determining root device";
+ return "";
+ }
+ dev_path = dev_path_cstr;
+ // Check that rootdev begins with "/dev/".
+ if (!StartsWithASCII(dev_path, dev_prefix, false)) {
+ LOG(WARNING) << "unexpected root device " << dev_path;
+ return "";
+ }
+ // Get the device name, e.g. "sda" from "/dev/sda".
+ dev_name = dev_path.substr(dev_prefix.length());
+ return "/sys/class/block/" + dev_name + "/stat";
+}
int main(int argc, char** argv) {
google::ParseCommandLineFlags(&argc, &argv, true);
MetricsLibrary metrics_lib;
metrics_lib.Init();
MetricsDaemon daemon;
- daemon.Init(false, &metrics_lib, kMetricsMainDiskStatsPath);
+ daemon.Init(false, &metrics_lib, MetricsMainDiskStatsPath());
daemon.Run(FLAGS_daemon);
}
