Commit 0e39702f authored by Patryk Wlazlyn's avatar Patryk Wlazlyn Committed by Len Brown
Browse files

tools/power turbostat: Enable non-privileged users to read sysfs counters 



A group of counters called "sysfs" displays software
C-state request counts and resulting perceived C-state residency.

They are not built-in counters that turbostat knows about ahead of time,
rather they are discovered in sysfs when turbostat starts.

Thus, they are added dynamically, using the same interface
as user-added MSR counters.

When turbostat enters "no-msr" mode, such as when running as a
non-privileged user, it clears all added counters.

Updating that to clear only actual MSR added counters
allows regular users to see the sysfs counters.

[lenb: commit message]

Signed-off-by: default avatarPatryk Wlazlyn <patryk.wlazlyn@linux.intel.com>
Signed-off-by: default avatarLen Brown <len.brown@intel.com>
parent d3e6f625

tools/power/x86/turbostat/turbostat.c

+31 −25
Original line number Diff line number Diff line
@@ -1377,36 +1377,42 @@ struct sys_counters { 
	struct msr_counter *pp;

} sys;



void free_sys_counters(void)

static size_t free_msr_counters_(struct msr_counter **pp)

{

	struct msr_counter *p = sys.tp, *pnext = NULL;

	struct msr_counter *p = NULL;

	size_t num_freed = 0;



	while (*pp) {

		p = *pp;



		if (p->msr_num != 0) {

			*pp = p->next;



	while (p) {

		pnext = p->next;

			free(p);

		p = pnext;

			++num_freed;



			continue;

		}



	p = sys.cp, pnext = NULL;

	while (p) {

		pnext = p->next;

		free(p);

		p = pnext;

		pp = &p->next;

	}



	p = sys.pp, pnext = NULL;

	while (p) {

		pnext = p->next;

		free(p);

		p = pnext;

	return num_freed;

}



	sys.added_thread_counters = 0;

	sys.added_core_counters = 0;

	sys.added_package_counters = 0;

	sys.tp = NULL;

	sys.cp = NULL;

	sys.pp = NULL;

/*

 * Free all added counters accessed via msr.

 */

static void free_sys_msr_counters(void)

{

	/* Thread counters */

	sys.added_thread_counters -= free_msr_counters_(&sys.tp);



	/* Core counters */

	sys.added_core_counters -= free_msr_counters_(&sys.cp);



	/* Package counters */

	sys.added_package_counters -= free_msr_counters_(&sys.pp);

}



struct system_summary {
@@ -1566,7 +1572,7 @@ static void bic_disable_msr_access(void) 


	bic_enabled &= ~bic_msrs;



	free_sys_counters();

	free_sys_msr_counters();

}



static long perf_event_open(struct perf_event_attr *hw_event, pid_t pid, int cpu, int group_fd, unsigned long flags)