@@ -105,7 +105,7 @@ int cat_perf_miss_val(int cpu_no, int n, char *cache_type)
return ret;
/* Get default cbm mask for L3/L2 cache */
- ret = get_cbm_mask(cache_type, &long_mask);
+ ret = get_mask_no_shareable(cache_type, &long_mask);
if (ret)
return ret;
count_of_bits = count_consecutive_bits(long_mask, NULL);
@@ -108,8 +108,11 @@ void tests_cleanup(void);
void mbm_test_cleanup(void);
int mba_schemata_change(int cpu_no, char *bw_report, char **benchmark_cmd);
void mba_test_cleanup(void);
+unsigned long create_bit_mask(unsigned int start, unsigned int len);
unsigned int count_consecutive_bits(unsigned long val, unsigned int *start);
int get_cbm_mask(char *cache_type, unsigned long *mask);
+int get_shareable_mask(char *cache_type, unsigned long *shareable_mask);
+int get_mask_no_shareable(char *cache_type, unsigned long *mask);
int get_cache_size(int cpu_no, char *cache_type, unsigned long *cache_size);
int cache_alloc_size(int cpu_no, char *cache_type, unsigned long slice_mask,
unsigned long *slice_size);
@@ -230,6 +230,16 @@ static int get_bit_mask(char *filename, unsigned long *mask)
return 0;
}
+/*
+ * create_bit_mask- Create bit mask from start,len pair
+ * @start: LSB of the mask
+ * @len Number of bits in the mask
+ */
+unsigned long create_bit_mask(unsigned int start, unsigned int len)
+{
+ return ((1UL << len) - 1UL) << start;
+}
+
/*
* count_consecutive_bits - Returns the longest train of bits in a bit mask
* @val A bit mask
@@ -283,6 +293,52 @@ int get_cbm_mask(char *cache_type, unsigned long *mask)
return 0;
}
+/*
+ * get_shareable_mask - Get shareable mask from shareable_bits for given cache
+ * @cache_type: Cache level L2/L3
+ * @shareable_mask: shareable mask returned as unsigned long
+ *
+ * Return: = 0 on success, < 0 on failure.
+ */
+int get_shareable_mask(char *cache_type, unsigned long *shareable_mask)
+{
+ char mask_path[1024];
+
+ if (!cache_type)
+ return -1;
+
+ snprintf(mask_path, sizeof(mask_path), "%s/%s/shareable_bits",
+ INFO_PATH, cache_type);
+
+ return get_bit_mask(mask_path, shareable_mask);
+}
+
+/*
+ * get_mask_no_shareable - Get CBM mask without shareable_bits for given cache
+ * @cache_type: Cache level L2/L3
+ * @mask: mask returned as unsigned long
+ *
+ * Return: = 0 on success, < 0 on failure.
+ */
+int get_mask_no_shareable(char *cache_type, unsigned long *mask)
+{
+ unsigned long full_mask, shareable_mask;
+ unsigned int start, len;
+
+ if (get_cbm_mask(cache_type, &full_mask) < 0)
+ return -1;
+ if (get_shareable_mask(cache_type, &shareable_mask) < 0)
+ return -1;
+
+ len = count_consecutive_bits(full_mask & ~shareable_mask, &start);
+ if (!len)
+ return -1;
+
+ *mask = create_bit_mask(start, len);
+
+ return 0;
+}
+
/*
* get_core_sibling - Get sibling core id from the same socket for given CPU
* @cpu_no: CPU number
CAT test doesn't take shareable bits into account, i.e., the test might be sharing cache with some devices (e.g., graphics). Introduce get_mask_no_shareable() and use it to provision an environment for CAT test where the allocated LLC is isolated better. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> --- tools/testing/selftests/resctrl/cat_test.c | 2 +- tools/testing/selftests/resctrl/resctrl.h | 3 ++ tools/testing/selftests/resctrl/resctrlfs.c | 56 +++++++++++++++++++++ 3 files changed, 60 insertions(+), 1 deletion(-)