xref: /linux/tools/testing/selftests/resctrl/resctrl.h (revision c34e9ab9a612ee8b18273398ef75c207b01f516d)
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 <sys/stat.h>
15 #include <sys/ioctl.h>
16 #include <sys/mount.h>
17 #include <sys/types.h>
18 #include <sys/wait.h>
19 #include <sys/select.h>
20 #include <sys/time.h>
21 #include <sys/eventfd.h>
22 #include <asm/unistd.h>
23 #include <linux/perf_event.h>
24 #include "../kselftest.h"
25 
26 #define MB			(1024 * 1024)
27 #define RESCTRL_PATH		"/sys/fs/resctrl"
28 #define PHYS_ID_PATH		"/sys/devices/system/cpu/cpu"
29 #define INFO_PATH		"/sys/fs/resctrl/info"
30 
31 /*
32  * CPU vendor IDs
33  *
34  * Define as bits because they're used for vendor_specific bitmask in
35  * the struct resctrl_test.
36  */
37 #define ARCH_INTEL     1
38 #define ARCH_AMD       2
39 
40 #define END_OF_TESTS	1
41 
42 #define BENCHMARK_ARGS		64
43 
44 #define MINIMUM_SPAN		(250 * MB)
45 
46 /*
47  * Memory bandwidth (in MiB) below which the bandwidth comparisons
48  * between iMC and resctrl are considered unreliable. For example RAS
49  * features or memory performance features that generate memory traffic
50  * may drive accesses that are counted differently by performance counters
51  * and MBM respectively, for instance generating "overhead" traffic which
52  * is not counted against any specific RMID.
53  */
54 #define THROTTLE_THRESHOLD	750
55 
56 /*
57  * fill_buf_param:	"fill_buf" benchmark parameters
58  * @buf_size:		Size (in bytes) of buffer used in benchmark.
59  *			"fill_buf" allocates and initializes buffer of
60  *			@buf_size. User can change value via command line.
61  * @memflush:		If false the buffer will not be flushed after
62  *			allocation and initialization, otherwise the
63  *			buffer will be flushed. User can change value via
64  *			command line (via integers with 0 interpreted as
65  *			false and anything else as true).
66  */
67 struct fill_buf_param {
68 	size_t		buf_size;
69 	bool		memflush;
70 };
71 
72 /*
73  * user_params:		User supplied parameters
74  * @cpu:		CPU number to which the benchmark will be bound to
75  * @bits:		Number of bits used for cache allocation size
76  * @benchmark_cmd:	Benchmark command to run during (some of the) tests
77  * @fill_buf:		Pointer to user provided parameters for "fill_buf",
78  *			NULL if user did not provide parameters and test
79  *			specific defaults should be used.
80  */
81 struct user_params {
82 	int cpu;
83 	int bits;
84 	const char *benchmark_cmd[BENCHMARK_ARGS];
85 	const struct fill_buf_param *fill_buf;
86 };
87 
88 /*
89  * resctrl_test:	resctrl test definition
90  * @name:		Test name
91  * @group:		Test group - a common name for tests that share some characteristic
92  *			(e.g., L3 CAT test belongs to the CAT group). Can be NULL
93  * @resource:		Resource to test (e.g., MB, L3, L2, etc.)
94  * @vendor_specific:	Bitmask for vendor-specific tests (can be 0 for universal tests)
95  * @disabled:		Test is disabled
96  * @feature_check:	Callback to check required resctrl features
97  * @run_test:		Callback to run the test
98  * @cleanup:		Callback to cleanup after the test
99  */
100 struct resctrl_test {
101 	const char	*name;
102 	const char	*group;
103 	const char	*resource;
104 	unsigned int	vendor_specific;
105 	bool		disabled;
106 	bool		(*feature_check)(const struct resctrl_test *test);
107 	int		(*run_test)(const struct resctrl_test *test,
108 				    const struct user_params *uparams);
109 	void		(*cleanup)(void);
110 };
111 
112 /*
113  * resctrl_val_param:	resctrl test parameters
114  * @ctrlgrp:		Name of the control monitor group (con_mon grp)
115  * @mongrp:		Name of the monitor group (mon grp)
116  * @filename:		Name of file to which the o/p should be written
117  * @init:		Callback function to initialize test environment
118  * @setup:		Callback function to setup per test run environment
119  * @measure:		Callback that performs the measurement (a single test)
120  * @fill_buf:		Parameters for default "fill_buf" benchmark.
121  *			Initialized with user provided parameters, possibly
122  *			adapted to be relevant to the test. If user does
123  *			not provide parameters for "fill_buf" nor a
124  *			replacement benchmark then initialized with defaults
125  *			appropriate for test. NULL if user provided
126  *			benchmark.
127  */
128 struct resctrl_val_param {
129 	const char		*ctrlgrp;
130 	const char		*mongrp;
131 	char			filename[64];
132 	unsigned long		mask;
133 	int			num_of_runs;
134 	int			(*init)(const struct resctrl_val_param *param,
135 					int domain_id);
136 	int			(*setup)(const struct resctrl_test *test,
137 					 const struct user_params *uparams,
138 					 struct resctrl_val_param *param);
139 	int			(*measure)(const struct user_params *uparams,
140 					   struct resctrl_val_param *param,
141 					   pid_t bm_pid);
142 	struct fill_buf_param	*fill_buf;
143 };
144 
145 struct perf_event_read {
146 	__u64 nr;			/* The number of events */
147 	struct {
148 		__u64 value;		/* The value of the event */
149 	} values[2];
150 };
151 
152 /*
153  * Memory location that consumes values compiler must not optimize away.
154  * Volatile ensures writes to this location cannot be optimized away by
155  * compiler.
156  */
157 extern volatile int *value_sink;
158 
159 extern char llc_occup_path[1024];
160 
161 int get_vendor(void);
162 bool check_resctrlfs_support(void);
163 int filter_dmesg(void);
164 int get_domain_id(const char *resource, int cpu_no, int *domain_id);
165 int mount_resctrlfs(void);
166 int umount_resctrlfs(void);
167 bool resctrl_resource_exists(const char *resource);
168 bool resctrl_mon_feature_exists(const char *resource, const char *feature);
169 bool resource_info_file_exists(const char *resource, const char *file);
170 bool test_resource_feature_check(const struct resctrl_test *test);
171 char *fgrep(FILE *inf, const char *str);
172 int taskset_benchmark(pid_t bm_pid, int cpu_no, cpu_set_t *old_affinity);
173 int taskset_restore(pid_t bm_pid, cpu_set_t *old_affinity);
174 int write_schemata(const char *ctrlgrp, char *schemata, int cpu_no,
175 		   const char *resource);
176 int write_bm_pid_to_resctrl(pid_t bm_pid, const char *ctrlgrp, const char *mongrp);
177 int perf_event_open(struct perf_event_attr *hw_event, pid_t pid, int cpu,
178 		    int group_fd, unsigned long flags);
179 unsigned char *alloc_buffer(size_t buf_size, bool memflush);
180 void mem_flush(unsigned char *buf, size_t buf_size);
181 void fill_cache_read(unsigned char *buf, size_t buf_size, bool once);
182 ssize_t get_fill_buf_size(int cpu_no, const char *cache_type);
183 int initialize_read_mem_bw_imc(void);
184 int measure_read_mem_bw(const struct user_params *uparams,
185 			struct resctrl_val_param *param, pid_t bm_pid);
186 void initialize_mem_bw_resctrl(const struct resctrl_val_param *param,
187 			       int domain_id);
188 int resctrl_val(const struct resctrl_test *test,
189 		const struct user_params *uparams,
190 		struct resctrl_val_param *param);
191 unsigned long create_bit_mask(unsigned int start, unsigned int len);
192 unsigned int count_contiguous_bits(unsigned long val, unsigned int *start);
193 int get_full_cbm(const char *cache_type, unsigned long *mask);
194 int get_mask_no_shareable(const char *cache_type, unsigned long *mask);
195 int get_cache_size(int cpu_no, const char *cache_type, unsigned long *cache_size);
196 int resource_info_unsigned_get(const char *resource, const char *filename, unsigned int *val);
197 void ctrlc_handler(int signum, siginfo_t *info, void *ptr);
198 int signal_handler_register(const struct resctrl_test *test);
199 void signal_handler_unregister(void);
200 unsigned int count_bits(unsigned long n);
201 
202 void perf_event_attr_initialize(struct perf_event_attr *pea, __u64 config);
203 void perf_event_initialize_read_format(struct perf_event_read *pe_read);
204 int perf_open(struct perf_event_attr *pea, pid_t pid, int cpu_no);
205 int perf_event_reset_enable(int pe_fd);
206 int perf_event_measure(int pe_fd, struct perf_event_read *pe_read,
207 		       const char *filename, pid_t bm_pid);
208 int measure_llc_resctrl(const char *filename, pid_t bm_pid);
209 void show_cache_info(int no_of_bits, __u64 avg_llc_val, size_t cache_span, bool lines);
210 
211 /*
212  * cache_portion_size - Calculate the size of a cache portion
213  * @cache_size:		Total cache size in bytes
214  * @portion_mask:	Cache portion mask
215  * @full_cache_mask:	Full Cache Bit Mask (CBM) for the cache
216  *
217  * Return: The size of the cache portion in bytes.
218  */
219 static inline unsigned long cache_portion_size(unsigned long cache_size,
220 					       unsigned long portion_mask,
221 					       unsigned long full_cache_mask)
222 {
223 	unsigned int bits = count_bits(full_cache_mask);
224 
225 	/*
226 	 * With no bits the full CBM, assume cache cannot be split into
227 	 * smaller portions. To avoid divide by zero, return cache_size.
228 	 */
229 	if (!bits)
230 		return cache_size;
231 
232 	return cache_size * count_bits(portion_mask) / bits;
233 }
234 
235 extern struct resctrl_test mbm_test;
236 extern struct resctrl_test mba_test;
237 extern struct resctrl_test cmt_test;
238 extern struct resctrl_test l3_cat_test;
239 extern struct resctrl_test l3_noncont_cat_test;
240 extern struct resctrl_test l2_noncont_cat_test;
241 
242 #endif /* RESCTRL_H */
243