Commit 16b7c275 authored Dec 01, 2014 by Prarit Bhargava Committed by Rafael J. Wysocki Dec 05, 2014

tools: cpupower: fix return checks for sysfs_get_idlestate_count()



Red Hat and Fedora use a bug reporting tool that gathers data about
"broken" systems called sosreport.  Among other things, it includes the
output of 'cpupower idle-info'.  Executing 'cpupower idle-info' on a
system that has cpuidle disabled via 'cpuidle.off=1' results in a 300
second hang in the cpupower application.

ie)
[root@intel-brickland-05]# cpupower idle-info
Could not determine cpuidle driver

Analyzing CPU 0:
Number of idle states: -19
[hang]

The problem is that the cpupower code only checks for a zero return from
sysfs_get_idlestate_count().  The function can return -ENODEV (-19) as
above.  This patch fixes callers to sysfs_get_idlestate_count() to check
the right return values.

Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

parent 009d0431

tools/power/cpupower/utils/cpuidle-info.c

+4 −4

Original line number	Diff line number	Diff line
		@@ -22,13 +22,13 @@

		static void cpuidle_cpu_output(unsigned int cpu, int verbose)
		{
		unsigned int idlestates, idlestate;
		int idlestates, idlestate;
		char *tmp;

		printf(_ ("Analyzing CPU %d:\n"), cpu);

		idlestates = sysfs_get_idlestate_count(cpu);
		if (idlestates == 0) {
		if (idlestates < 1) {
		printf(_("CPU %u: No idle states\n"), cpu);
		return;
		}
		@@ -100,10 +100,10 @@ static void cpuidle_general_output(void)
		static void proc_cpuidle_cpu_output(unsigned int cpu)
		{
		long max_allowed_cstate = 2000000000;
		unsigned int cstate, cstates;
		int cstate, cstates;

		cstates = sysfs_get_idlestate_count(cpu);
		if (cstates == 0) {
		if (cstates < 1) {
		printf(_("CPU %u: No C-states info\n"), cpu);
		return;
		}