commit 861ff65d099c2b958321ca659786c7eb8a9a1130

Author: William Cohen <wcohen@redhat.com>

Date:   Wed Nov 15 23:47:16 2017 -0500

    Avoid statically limiting the number of lmsensor events allowed

    Some high-end server machines provide more events than the 512 entries

    limit imposed by the LM_SENSORS_MAX_COUNTERS define in the lmsensor

    component (observed 577 entries on one machine).  When this limit was

    exceeded the lmsensor component would write beyond the array bounds

    causing ctests/all_native_events to crash.  Modified the lmsensor code

    to dynamically allocate the required space for all the available

    lmsensor entries on the machine. This allows ctests/all_native_events

    to run to completion.

diff --git a/src/components/lmsensors/linux-lmsensors.c b/src/components/lmsensors/linux-lmsensors.c

index c9d8530d..07be89fd 100644

--- a/src/components/lmsensors/linux-lmsensors.c

+++ b/src/components/lmsensors/linux-lmsensors.c

@@ -43,8 +43,6 @@

 /*************************  DEFINES SECTION  ***********************************

  *******************************************************************************/

-/* this number assumes that there will never be more events than indicated */

-#define LM_SENSORS_MAX_COUNTERS 512

 // time in usecs

 #define LM_SENSORS_REFRESHTIME 200000

@@ -82,7 +80,6 @@ typedef struct _lmsensors_reg_alloc

 typedef struct _lmsensors_control_state

 {

-	long_long counts[LM_SENSORS_MAX_COUNTERS];	// used for caching

 	long_long lastupdate;

 } _lmsensors_control_state_t;

@@ -100,6 +97,7 @@ typedef struct _lmsensors_context

 static _lmsensors_native_event_entry_t *lm_sensors_native_table;

 /* number of events in the table*/

 static int num_events = 0;

+long_long *cached_counts = NULL;	// used for caching readings

@@ -304,6 +302,9 @@ _lmsensors_init_component( int cidx )

     num_events = detectSensors(  );

     SUBDBG("Found %d sensors\n",num_events);

+    _lmsensors_vector.cmp_info.num_mpx_cntrs = num_events;

+    _lmsensors_vector.cmp_info.num_cntrs = num_events;

+

     if ( ( lm_sensors_native_table =

 	   calloc( num_events, sizeof ( _lmsensors_native_event_entry_t )))

 				   == NULL ) {

@@ -312,6 +313,14 @@ _lmsensors_init_component( int cidx )

        return PAPI_ENOMEM;

     }

+    cached_counts = (long long*) calloc(num_events, sizeof(long long));

+

+    if (cached_counts == NULL) {

+        strncpy(_lmsensors_vector.cmp_info.disabled_reason,

+               "Could not malloc room",PAPI_MAX_STR_LEN);

+	return PAPI_ENOMEM;

+    }

+

     if ( ( unsigned ) num_events != createNativeEvents(  ) ) {

        strncpy(_lmsensors_vector.cmp_info.disabled_reason,

 	      "LM_SENSOR number mismatch",PAPI_MAX_STR_LEN);

@@ -413,8 +422,7 @@ _lmsensors_init_control_state( hwd_control_state_t *ctl )

 	int i;

 	for ( i = 0; i < num_events; i++ )

-		( ( _lmsensors_control_state_t * ) ctl )->counts[i] =

-			getEventValue( i );

+		cached_counts[i] = getEventValue( i );

 	( ( _lmsensors_control_state_t * ) ctl )->lastupdate =

 		PAPI_get_real_usec(  );

@@ -465,12 +473,12 @@ _lmsensors_read( hwd_context_t *ctx, hwd_control_state_t *ctl,

     if ( start - control->lastupdate > 200000 ) {	// cache refresh

        for ( i = 0; i < num_events; i++ ) {

-	   control->counts[i] = getEventValue( i );

+	   cached_counts[i] = getEventValue( i );

        }

        control->lastupdate = PAPI_get_real_usec(  );

     }

-    *events = control->counts;

+    *events = cached_counts;

     return PAPI_OK;

 }

@@ -478,6 +486,8 @@ _lmsensors_read( hwd_context_t *ctx, hwd_control_state_t *ctl,

 int

 _lmsensors_shutdown_component( void )

 {

+	if (cached_counts)

+		free(cached_counts);

 	/* Call the libsensors cleaning function before leaving */

 	sensors_cleanup(  );

@@ -627,8 +637,8 @@ papi_vector_t _lmsensors_vector = {

 	.short_name = "lmsensors",

 	.version = "5.0",

 	.description = "Linux LMsensor statistics",

-	.num_mpx_cntrs = LM_SENSORS_MAX_COUNTERS,

-	.num_cntrs = LM_SENSORS_MAX_COUNTERS,

+	.num_mpx_cntrs = 0,

+	.num_cntrs = 0,

 	.default_domain = PAPI_DOM_USER,

 	//.available_domains = PAPI_DOM_USER,

 	.default_granularity = PAPI_GRN_THR,