xref: /linux/tools/testing/selftests/resctrl/resctrl.h (revision e814f3fd16acfb7f9966773953de8f740a1e3202)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef RESCTRL_H
3 #define RESCTRL_H
4 #include <stdio.h>
5 #include <math.h>
6 #include <errno.h>
7 #include <sched.h>
8 #include <stdlib.h>
9 #include <unistd.h>
10 #include <string.h>
11 #include <signal.h>
12 #include <dirent.h>
13 #include <stdbool.h>
14 #include <ctype.h>
15 #include <sys/stat.h>
16 #include <sys/ioctl.h>
17 #include <sys/mount.h>
18 #include <sys/types.h>
19 #include <sys/wait.h>
20 #include <sys/select.h>
21 #include <sys/time.h>
22 #include <sys/eventfd.h>
23 #include <asm/unistd.h>
24 #include <linux/perf_event.h>
25 #include <linux/compiler.h>
26 #include "../kselftest.h"
27 
28 #define MB			(1024 * 1024)
29 #define RESCTRL_PATH		"/sys/fs/resctrl"
30 #define PHYS_ID_PATH		"/sys/devices/system/cpu/cpu"
31 #define INFO_PATH		"/sys/fs/resctrl/info"
32 
33 /*
34  * CPU vendor IDs
35  *
36  * Define as bits because they're used for vendor_specific bitmask in
37  * the struct resctrl_test.
38  */
39 #define ARCH_INTEL     1
40 #define ARCH_AMD       2
41 
42 #define END_OF_TESTS	1
43 
44 #define BENCHMARK_ARGS		64
45 
46 #define MINIMUM_SPAN		(250 * MB)
47 
48 /*
49  * Memory bandwidth (in MiB) below which the bandwidth comparisons
50  * between iMC and resctrl are considered unreliable. For example RAS
51  * features or memory performance features that generate memory traffic
52  * may drive accesses that are counted differently by performance counters
53  * and MBM respectively, for instance generating "overhead" traffic which
54  * is not counted against any specific RMID.
55  */
56 #define THROTTLE_THRESHOLD	750
57 
58 /*
59  * fill_buf_param:	"fill_buf" benchmark parameters
60  * @buf_size:		Size (in bytes) of buffer used in benchmark.
61  *			"fill_buf" allocates and initializes buffer of
62  *			@buf_size. User can change value via command line.
63  * @memflush:		If false the buffer will not be flushed after
64  *			allocation and initialization, otherwise the
65  *			buffer will be flushed. User can change value via
66  *			command line (via integers with 0 interpreted as
67  *			false and anything else as true).
68  */
69 struct fill_buf_param {
70 	size_t		buf_size;
71 	bool		memflush;
72 };
73 
74 /*
75  * user_params:		User supplied parameters
76  * @cpu:		CPU number to which the benchmark will be bound to
77  * @bits:		Number of bits used for cache allocation size
78  * @benchmark_cmd:	Benchmark command to run during (some of the) tests
79  * @fill_buf:		Pointer to user provided parameters for "fill_buf",
80  *			NULL if user did not provide parameters and test
81  *			specific defaults should be used.
82  */
83 struct user_params {
84 	int cpu;
85 	int bits;
86 	const char *benchmark_cmd[BENCHMARK_ARGS];
87 	const struct fill_buf_param *fill_buf;
88 };
89 
90 /*
91  * resctrl_test:	resctrl test definition
92  * @name:		Test name
93  * @group:		Test group - a common name for tests that share some characteristic
94  *			(e.g., L3 CAT test belongs to the CAT group). Can be NULL
95  * @resource:		Resource to test (e.g., MB, L3, L2, etc.)
96  * @vendor_specific:	Bitmask for vendor-specific tests (can be 0 for universal tests)
97  * @disabled:		Test is disabled
98  * @feature_check:	Callback to check required resctrl features
99  * @run_test:		Callback to run the test
100  * @cleanup:		Callback to cleanup after the test
101  */
102 struct resctrl_test {
103 	const char	*name;
104 	const char	*group;
105 	const char	*resource;
106 	unsigned int	vendor_specific;
107 	bool		disabled;
108 	bool		(*feature_check)(const struct resctrl_test *test);
109 	int		(*run_test)(const struct resctrl_test *test,
110 				    const struct user_params *uparams);
111 	void		(*cleanup)(void);
112 };
113 
114 /*
115  * resctrl_val_param:	resctrl test parameters
116  * @ctrlgrp:		Name of the control monitor group (con_mon grp)
117  * @mongrp:		Name of the monitor group (mon grp)
118  * @filename:		Name of file to which the o/p should be written
119  * @init:		Callback function to initialize test environment
120  * @setup:		Callback function to setup per test run environment
121  * @measure:		Callback that performs the measurement (a single test)
122  * @fill_buf:		Parameters for default "fill_buf" benchmark.
123  *			Initialized with user provided parameters, possibly
124  *			adapted to be relevant to the test. If user does
125  *			not provide parameters for "fill_buf" nor a
126  *			replacement benchmark then initialized with defaults
127  *			appropriate for test. NULL if user provided
128  *			benchmark.
129  */
130 struct resctrl_val_param {
131 	const char		*ctrlgrp;
132 	const char		*mongrp;
133 	char			filename[64];
134 	unsigned long		mask;
135 	int			num_of_runs;
136 	int			(*init)(const struct resctrl_val_param *param,
137 					int domain_id);
138 	int			(*setup)(const struct resctrl_test *test,
139 					 const struct user_params *uparams,
140 					 struct resctrl_val_param *param);
141 	int			(*measure)(const struct user_params *uparams,
142 					   struct resctrl_val_param *param,
143 					   pid_t bm_pid);
144 	struct fill_buf_param	*fill_buf;
145 };
146 
147 struct perf_event_read {
148 	__u64 nr;			/* The number of events */
149 	struct {
150 		__u64 value;		/* The value of the event */
151 	} values[2];
152 };
153 
154 /*
155  * Memory location that consumes values compiler must not optimize away.
156  * Volatile ensures writes to this location cannot be optimized away by
157  * compiler.
158  */
159 extern volatile int *value_sink;
160 
161 extern int snc_unreliable;
162 
163 extern char llc_occup_path[1024];
164 
165 int snc_nodes_per_l3_cache(void);
166 int get_vendor(void);
167 bool check_resctrlfs_support(void);
168 int filter_dmesg(void);
169 int get_domain_id(const char *resource, int cpu_no, int *domain_id);
170 int mount_resctrlfs(void);
171 int umount_resctrlfs(void);
172 bool resctrl_resource_exists(const char *resource);
173 bool resctrl_mon_feature_exists(const char *resource, const char *feature);
174 bool resource_info_file_exists(const char *resource, const char *file);
175 bool test_resource_feature_check(const struct resctrl_test *test);
176 char *fgrep(FILE *inf, const char *str);
177 int taskset_benchmark(pid_t bm_pid, int cpu_no, cpu_set_t *old_affinity);
178 int taskset_restore(pid_t bm_pid, cpu_set_t *old_affinity);
179 int write_schemata(const char *ctrlgrp, char *schemata, int cpu_no,
180 		   const char *resource);
181 int write_bm_pid_to_resctrl(pid_t bm_pid, const char *ctrlgrp, const char *mongrp);
182 int perf_event_open(struct perf_event_attr *hw_event, pid_t pid, int cpu,
183 		    int group_fd, unsigned long flags);
184 unsigned char *alloc_buffer(size_t buf_size, bool memflush);
185 void mem_flush(unsigned char *buf, size_t buf_size);
186 void fill_cache_read(unsigned char *buf, size_t buf_size, bool once);
187 ssize_t get_fill_buf_size(int cpu_no, const char *cache_type);
188 int initialize_read_mem_bw_imc(void);
189 int measure_read_mem_bw(const struct user_params *uparams,
190 			struct resctrl_val_param *param, pid_t bm_pid);
191 void initialize_mem_bw_resctrl(const struct resctrl_val_param *param,
192 			       int domain_id);
193 int resctrl_val(const struct resctrl_test *test,
194 		const struct user_params *uparams,
195 		struct resctrl_val_param *param);
196 unsigned long create_bit_mask(unsigned int start, unsigned int len);
197 unsigned int count_contiguous_bits(unsigned long val, unsigned int *start);
198 int get_full_cbm(const char *cache_type, unsigned long *mask);
199 int get_mask_no_shareable(const char *cache_type, unsigned long *mask);
200 int get_cache_size(int cpu_no, const char *cache_type, unsigned long *cache_size);
201 int resource_info_unsigned_get(const char *resource, const char *filename, unsigned int *val);
202 void ctrlc_handler(int signum, siginfo_t *info, void *ptr);
203 int signal_handler_register(const struct resctrl_test *test);
204 void signal_handler_unregister(void);
205 unsigned int count_bits(unsigned long n);
206 int snc_kernel_support(void);
207 
208 void perf_event_attr_initialize(struct perf_event_attr *pea, __u64 config);
209 void perf_event_initialize_read_format(struct perf_event_read *pe_read);
210 int perf_open(struct perf_event_attr *pea, pid_t pid, int cpu_no);
211 int perf_event_reset_enable(int pe_fd);
212 int perf_event_measure(int pe_fd, struct perf_event_read *pe_read,
213 		       const char *filename, pid_t bm_pid);
214 int measure_llc_resctrl(const char *filename, pid_t bm_pid);
215 void show_cache_info(int no_of_bits, __u64 avg_llc_val, size_t cache_span, bool lines);
216 
217 /*
218  * cache_portion_size - Calculate the size of a cache portion
219  * @cache_size:		Total cache size in bytes
220  * @portion_mask:	Cache portion mask
221  * @full_cache_mask:	Full Cache Bit Mask (CBM) for the cache
222  *
223  * Return: The size of the cache portion in bytes.
224  */
225 static inline unsigned long cache_portion_size(unsigned long cache_size,
226 					       unsigned long portion_mask,
227 					       unsigned long full_cache_mask)
228 {
229 	unsigned int bits = count_bits(full_cache_mask);
230 
231 	/*
232 	 * With no bits the full CBM, assume cache cannot be split into
233 	 * smaller portions. To avoid divide by zero, return cache_size.
234 	 */
235 	if (!bits)
236 		return cache_size;
237 
238 	return cache_size * count_bits(portion_mask) / bits;
239 }
240 
241 extern struct resctrl_test mbm_test;
242 extern struct resctrl_test mba_test;
243 extern struct resctrl_test cmt_test;
244 extern struct resctrl_test l3_cat_test;
245 extern struct resctrl_test l3_noncont_cat_test;
246 extern struct resctrl_test l2_noncont_cat_test;
247 
248 #endif /* RESCTRL_H */
249