linux/tools/testing/selftests/resctrl/resctrl.h

124 lines
4.0 KiB
C
Raw Normal View History

/* SPDX-License-Identifier: GPL-2.0 */
#define _GNU_SOURCE
#ifndef RESCTRL_H
#define RESCTRL_H
#include <stdio.h>
#include <stdarg.h>
#include <math.h>
#include <errno.h>
#include <sched.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <signal.h>
#include <dirent.h>
#include <stdbool.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/mount.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/select.h>
#include <sys/time.h>
#include <sys/eventfd.h>
#include <asm/unistd.h>
#include <linux/perf_event.h>
#include "../kselftest.h"
#define MB (1024 * 1024)
#define RESCTRL_PATH "/sys/fs/resctrl"
#define PHYS_ID_PATH "/sys/devices/system/cpu/cpu"
#define CBM_MASK_PATH "/sys/fs/resctrl/info"
selftests/resctrl: Use resctrl/info for feature detection Resctrl test suite before running any unit test (like cmt, cat, mbm and mba) should first check if the feature is enabled (by kernel and not just supported by H/W) on the platform or not. validate_resctrl_feature_request() is supposed to do that. This function intends to grep for relevant flags in /proc/cpuinfo but there are several issues here 1. validate_resctrl_feature_request() calls fgrep() to get flags from /proc/cpuinfo. But, fgrep() can only return a string with maximum of 255 characters and hence the complete cpu flags are never returned. 2. The substring search logic is also busted. If strstr() finds requested resctrl feature in the cpu flags, it returns pointer to the first occurrence. But, the logic negates the return value of strstr() and hence validate_resctrl_feature_request() returns false if the feature is present in the cpu flags and returns true if the feature is not present. 3. validate_resctrl_feature_request() checks if a resctrl feature is reported in /proc/cpuinfo flags or not. Having a cpu flag means that the H/W supports the feature, but it doesn't mean that the kernel enabled it. A user could selectively enable only a subset of resctrl features using kernel command line arguments. Hence, /proc/cpuinfo isn't a reliable source to check if a feature is enabled or not. The 3rd issue being the major one and fixing it requires changing the way validate_resctrl_feature_request() works. Since, /proc/cpuinfo isn't the right place to check if a resctrl feature is enabled or not, a more appropriate place is /sys/fs/resctrl/info directory. Change validate_resctrl_feature_request() such that, 1. For cat, check if /sys/fs/resctrl/info/L3 directory is present or not 2. For mba, check if /sys/fs/resctrl/info/MB directory is present or not 3. For cmt, check if /sys/fs/resctrl/info/L3_MON directory is present and check if /sys/fs/resctrl/info/L3_MON/mon_features has llc_occupancy 4. For mbm, check if /sys/fs/resctrl/info/L3_MON directory is present and check if /sys/fs/resctrl/info/L3_MON/mon_features has mbm_<total/local>_bytes Please note that only L3_CAT, L3_CMT, MBA and MBM are supported. CDP and L2 variants can be added later. Reported-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2021-03-17 05:22:47 +03:00
#define L3_PATH "/sys/fs/resctrl/info/L3"
#define MB_PATH "/sys/fs/resctrl/info/MB"
#define L3_MON_PATH "/sys/fs/resctrl/info/L3_MON"
#define L3_MON_FEATURES_PATH "/sys/fs/resctrl/info/L3_MON/mon_features"
#define ARCH_INTEL 1
#define ARCH_AMD 2
#define PARENT_EXIT(err_msg) \
do { \
perror(err_msg); \
kill(ppid, SIGKILL); \
exit(EXIT_FAILURE); \
} while (0)
/*
* resctrl_val_param: resctrl test parameters
* @resctrl_val: Resctrl feature (Eg: mbm, mba.. etc)
* @ctrlgrp: Name of the control monitor group (con_mon grp)
* @mongrp: Name of the monitor group (mon grp)
* @cpu_no: CPU number to which the benchmark would be binded
* @span: Memory bytes accessed in each benchmark iteration
* @mum_resctrlfs: Should the resctrl FS be remounted?
* @filename: Name of file to which the o/p should be written
* @bw_report: Bandwidth report type (reads vs writes)
* @setup: Call back function to setup test environment
*/
struct resctrl_val_param {
char *resctrl_val;
char ctrlgrp[64];
char mongrp[64];
int cpu_no;
unsigned long span;
int mum_resctrlfs;
char filename[64];
char *bw_report;
unsigned long mask;
int num_of_runs;
int (*setup)(int num, ...);
};
#define MBM_STR "mbm"
#define MBA_STR "mba"
#define CMT_STR "cmt"
#define CAT_STR "cat"
extern pid_t bm_pid, ppid;
extern char llc_occup_path[1024];
int get_vendor(void);
bool check_resctrlfs_support(void);
int filter_dmesg(void);
int remount_resctrlfs(bool mum_resctrlfs);
int get_resource_id(int cpu_no, int *resource_id);
int umount_resctrlfs(void);
int validate_bw_report_request(char *bw_report);
selftests/resctrl: Use resctrl/info for feature detection Resctrl test suite before running any unit test (like cmt, cat, mbm and mba) should first check if the feature is enabled (by kernel and not just supported by H/W) on the platform or not. validate_resctrl_feature_request() is supposed to do that. This function intends to grep for relevant flags in /proc/cpuinfo but there are several issues here 1. validate_resctrl_feature_request() calls fgrep() to get flags from /proc/cpuinfo. But, fgrep() can only return a string with maximum of 255 characters and hence the complete cpu flags are never returned. 2. The substring search logic is also busted. If strstr() finds requested resctrl feature in the cpu flags, it returns pointer to the first occurrence. But, the logic negates the return value of strstr() and hence validate_resctrl_feature_request() returns false if the feature is present in the cpu flags and returns true if the feature is not present. 3. validate_resctrl_feature_request() checks if a resctrl feature is reported in /proc/cpuinfo flags or not. Having a cpu flag means that the H/W supports the feature, but it doesn't mean that the kernel enabled it. A user could selectively enable only a subset of resctrl features using kernel command line arguments. Hence, /proc/cpuinfo isn't a reliable source to check if a feature is enabled or not. The 3rd issue being the major one and fixing it requires changing the way validate_resctrl_feature_request() works. Since, /proc/cpuinfo isn't the right place to check if a resctrl feature is enabled or not, a more appropriate place is /sys/fs/resctrl/info directory. Change validate_resctrl_feature_request() such that, 1. For cat, check if /sys/fs/resctrl/info/L3 directory is present or not 2. For mba, check if /sys/fs/resctrl/info/MB directory is present or not 3. For cmt, check if /sys/fs/resctrl/info/L3_MON directory is present and check if /sys/fs/resctrl/info/L3_MON/mon_features has llc_occupancy 4. For mbm, check if /sys/fs/resctrl/info/L3_MON directory is present and check if /sys/fs/resctrl/info/L3_MON/mon_features has mbm_<total/local>_bytes Please note that only L3_CAT, L3_CMT, MBA and MBM are supported. CDP and L2 variants can be added later. Reported-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2021-03-17 05:22:47 +03:00
bool validate_resctrl_feature_request(const char *resctrl_val);
char *fgrep(FILE *inf, const char *str);
int taskset_benchmark(pid_t bm_pid, int cpu_no);
void run_benchmark(int signum, siginfo_t *info, void *ucontext);
int write_schemata(char *ctrlgrp, char *schemata, int cpu_no,
char *resctrl_val);
int write_bm_pid_to_resctrl(pid_t bm_pid, char *ctrlgrp, char *mongrp,
char *resctrl_val);
int perf_event_open(struct perf_event_attr *hw_event, pid_t pid, int cpu,
int group_fd, unsigned long flags);
int run_fill_buf(unsigned long span, int malloc_and_init_memory, int memflush,
int op, char *resctrl_va);
int resctrl_val(char **benchmark_cmd, struct resctrl_val_param *param);
int mbm_bw_change(int span, int cpu_no, char *bw_report, char **benchmark_cmd);
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);
int get_cbm_mask(char *cache_type, char *cbm_mask);
int get_cache_size(int cpu_no, char *cache_type, unsigned long *cache_size);
void ctrlc_handler(int signum, siginfo_t *info, void *ptr);
int cat_val(struct resctrl_val_param *param);
void cat_test_cleanup(void);
int cat_perf_miss_val(int cpu_no, int no_of_bits, char *cache_type);
int cmt_resctrl_val(int cpu_no, int n, char **benchmark_cmd);
unsigned int count_bits(unsigned long n);
void cmt_test_cleanup(void);
int get_core_sibling(int cpu_no);
int measure_cache_vals(struct resctrl_val_param *param, int bm_pid);
int show_cache_info(unsigned long sum_llc_val, int no_of_bits,
unsigned long cache_span, unsigned long max_diff,
unsigned long max_diff_percent, unsigned long num_of_runs,
bool platform, bool cmt);
#endif /* RESCTRL_H */