Fenghua, Sai, Couple of problems with these patches(see below). Please check again.
> -----Original Message----- > From: Fenghua Yu <fenghua...@intel.com> > Sent: Friday, December 21, 2018 6:21 PM > To: Thomas Gleixner <t...@linutronix.de>; Ingo Molnar > <mi...@redhat.com>; H Peter Anvin <h...@zytor.com>; Tony Luck > <tony.l...@intel.com>; Peter Zijlstra <pet...@infradead.org>; Reinette > Chatre <reinette.cha...@intel.com>; Moger, Babu > <babu.mo...@amd.com>; James Morse <james.mo...@arm.com>; > Xiaochen Shen <xiaochen.s...@intel.com>; Ravi V Shankar > <ravi.v.shan...@intel.com>; Sai Praneeth Prakhya > <sai.praneeth.prak...@intel.com>; Arshiya Hayatkhan Pathan > <arshiya.hayatkhan.pat...@intel.com> > Cc: linux-kernel <linux-kernel@vger.kernel.org>; Fenghua Yu > <fenghua...@intel.com> > Subject: [PATCH v4 08/10] selftests/resctrl Add Cache QoS Monitoring (CQM) > selftest > > From: Arshiya Hayatkhan Pathan <arshiya.hayatkhan.pat...@intel.com> > > Cache QoS Monitoring (CQM) selftest starts stressful cache benchmark > with specified size of memory to access the cache. Last Level cache > occupancy reported by CQM should be close to the size of the memory. > > Signed-off-by: Arshiya Hayatkhan Pathan > <arshiya.hayatkhan.pat...@intel.com> > Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prak...@intel.com> > Signed-off-by: Fenghua Yu <fenghua...@intel.com> > --- > tools/testing/selftests/resctrl/Makefile | 2 +- > tools/testing/selftests/resctrl/cache.c | 102 ++++++++ > tools/testing/selftests/resctrl/cqm_test.c | 169 +++++++++++++ > tools/testing/selftests/resctrl/fill_buf.c | 107 ++++---- > tools/testing/selftests/resctrl/mba_test.c | 3 +- > tools/testing/selftests/resctrl/mbm_test.c | 3 +- > tools/testing/selftests/resctrl/resctrl.h | 30 ++- > .../testing/selftests/resctrl/resctrl_tests.c | 82 +++++-- > tools/testing/selftests/resctrl/resctrl_val.c | 106 ++++---- > tools/testing/selftests/resctrl/resctrlfs.c | 231 ++++++++++++++++-- > 10 files changed, 691 insertions(+), 144 deletions(-) > create mode 100644 tools/testing/selftests/resctrl/cache.c > create mode 100644 tools/testing/selftests/resctrl/cqm_test.c > > diff --git a/tools/testing/selftests/resctrl/Makefile > b/tools/testing/selftests/resctrl/Makefile > index bf9f55e71d0c..664561cd76e6 100644 > --- a/tools/testing/selftests/resctrl/Makefile > +++ b/tools/testing/selftests/resctrl/Makefile > @@ -8,7 +8,7 @@ all: resctrl_tests > > resctrl_tests: *.o > $(CC) $(CFLAGS) -o resctrl_tests resctrl_tests.o resctrlfs.o \ > - membw.o fill_buf.o mbm_test.o mba_test.o > + resctrl_val.o fill_buf.o mbm_test.o mba_test.o cache.o > cqm_test.o > > .PHONY: clean > > diff --git a/tools/testing/selftests/resctrl/cache.c > b/tools/testing/selftests/resctrl/cache.c > new file mode 100644 > index 000000000000..1256590ef804 > --- /dev/null > +++ b/tools/testing/selftests/resctrl/cache.c > @@ -0,0 +1,102 @@ > +// SPDX-License-Identifier: GPL-2.0 > + > +#include <stdint.h> > +#include "resctrl.h" > + > +struct read_format { > + __u64 nr; /* The number of events */ > + struct { > + __u64 value; /* The value of the event */ > + } values[2]; > +}; > + > +char cbm_mask[256]; > +unsigned long long_mask; > +char llc_occup_path[1024]; > + > +/* > + * Get LLC Occupancy as reported by RESCTRL FS > + * For CQM, > + * 1. If con_mon grp and mon grp given, then read from mon grp in > + * con_mon grp > + * 2. If only con_mon grp given, then read from con_mon grp > + * 3. If both not given, then read from root con_mon grp > + * For CAT, > + * 1. If con_mon grp given, then read from it > + * 2. If con_mon grp not given, then read from root con_mon grp > + * > + * Return: =0 on success. <0 on failure. > + */ > +static int get_llc_occu_resctrl(unsigned long *llc_occupancy) > +{ > + FILE *fp; > + > + fp = fopen(llc_occup_path, "r"); > + if (!fp) { > + perror("Failed to open results file"); > + > + return errno; > + } > + if (fscanf(fp, "%lu", llc_occupancy) <= 0) { > + perror("Could not get llc occupancy"); > + fclose(fp); > + > + return -1; > + } > + fclose(fp); > + > + return 0; > +} > + > +/* > + * print_results_cache: the cache results are stored in a file > + * @filename: file that stores the results > + * @bm_pid: child pid that runs benchmark > + * @llc_value: perf miss value / > + * llc occupancy value reported by resctrl FS > + * > + * Return: 0 on success. non-zero on failure. > + */ > +static int print_results_cache(char *filename, int bm_pid, > + unsigned long llc_value) > +{ > + FILE *fp; > + > + if (strcmp(filename, "stdio") == 0 || strcmp(filename, "stderr") == 0) > { > + printf("Pid: %d \t LLC_value: %lu\n", bm_pid, > + llc_value); > + } else { > + fp = fopen(filename, "a"); > + if (!fp) { > + perror("Cannot open results file"); > + > + return errno; > + } > + fprintf(fp, "Pid: %d \t llc_value: %lu\n", bm_pid, > + llc_value); > + fclose(fp); > + } > + > + return 0; > +} > + > +int measure_cache_vals(struct resctrl_val_param *param, int bm_pid) > +{ > + unsigned long llc_occu_resc = 0, llc_value = 0; > + int ret; > + > + /* > + * Measure llc occupancy from resctrl. > + */ > + if (!strcmp(param->resctrl_val, "cqm")) { > + ret = get_llc_occu_resctrl(&llc_occu_resc); > + if (ret < 0) > + return ret; > + llc_value = llc_occu_resc; > + } > + ret = print_results_cache(param->filename, bm_pid, llc_value); > + if (ret) > + return ret; > + > + return 0; > +} > diff --git a/tools/testing/selftests/resctrl/cqm_test.c > b/tools/testing/selftests/resctrl/cqm_test.c > new file mode 100644 > index 000000000000..cddee364c88a > --- /dev/null > +++ b/tools/testing/selftests/resctrl/cqm_test.c > @@ -0,0 +1,169 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Cache Monitoring Technology (CQM) test > + * > + * Copyright (C) 2018 Intel Corporation > + * > + * Authors: > + * Arshiya Hayatkhan Pathan <arshiya.hayatkhan.pat...@intel.com> > + * Sai Praneeth Prakhya <sai.praneeth.prak...@intel.com>, > + * Fenghua Yu <fenghua...@intel.com> > + */ > +#include "resctrl.h" > +#include <unistd.h> > + > +#define RESULT_FILE_NAME "result_cqm" > +#define NUM_OF_RUNS 5 > +#define MAX_DIFF 2000000 > +#define MAX_DIFF_PERCENT 15 > + > +int count_of_bits; > +char cbm_mask[256]; > +unsigned long long_mask; > +unsigned long cache_size; > + > +static int cqm_setup(int num, ...) > +{ > + struct resctrl_val_param *p; > + va_list param; > + > + va_start(param, num); > + p = va_arg(param, struct resctrl_val_param *); > + va_end(param); > + > + /* Run NUM_OF_RUNS times */ > + if (p->num_of_runs >= NUM_OF_RUNS) > + return -1; > + > + p->num_of_runs++; > + > + return 0; > +} > + > +static void show_cache_info(unsigned long sum_llc_occu_resc, int > no_of_bits, > + unsigned long span) > +{ > + unsigned long avg_llc_occu_resc = 0; > + long avg_diff = 0; > + float diff_percent; > + > + avg_llc_occu_resc = sum_llc_occu_resc / (NUM_OF_RUNS - 1); > + avg_diff = (long long)abs(span - avg_llc_occu_resc); > + > + printf("\nResults are displayed in (Bytes)\n"); > + printf("\nNumber of bits: %d \t", no_of_bits); > + printf("Avg_llc_occu_resc: %lu \t", avg_llc_occu_resc); > + printf("llc_occu_exp (span): %lu \t", span); > + > + diff_percent = (((float)span - avg_llc_occu_resc) / span) * 100; > + > + printf("Diff: %ld \t", avg_diff); > + printf("Percent diff=%d\t", abs((int)diff_percent)); > + > + if ((abs((int)diff_percent) <= MAX_DIFF_PERCENT) || > + (abs(avg_diff) <= MAX_DIFF)) > + printf("Passed\n"); > + else > + printf("Failed\n"); > +} > + > +static int check_results(struct resctrl_val_param *param, int no_of_bits) > +{ > + char *token_array[8], temp[512]; > + unsigned long sum_llc_occu_resc = 0; > + int runs = 0; > + FILE *fp; > + > + printf("\nchecking for pass/fail\n"); > + fp = fopen(param->filename, "r"); > + if (!fp) { > + perror("Error in opening file\n"); > + > + return errno; > + } > + > + while (fgets(temp, 1024, fp)) { > + char *token = strtok(temp, ":\t"); > + int fields = 0; > + > + while (token) { > + token_array[fields++] = token; > + token = strtok(NULL, ":\t"); > + } > + > + /* Field 3 is llc occ resc value */ > + if (runs > 0) > + sum_llc_occu_resc += atol(token_array[3]); > + runs++; > + } > + fclose(fp); > + show_cache_info(sum_llc_occu_resc, no_of_bits, param->span); > + > + return 0; > +} > + > +void cqm_test_cleanup(void) > +{ > + remove(RESULT_FILE_NAME); > +} > + > +int cqm_resctrl_val(int core_id, int n, char **benchmark_cmd) > +{ > + int ret, mum_resctrlfs; > + > + cache_size = 0; > + mum_resctrlfs = 1; > + > + ret = remount_resctrlfs(mum_resctrlfs); > + if (ret) > + return ret; > + > + ret = get_cbm_mask("L3"); > + if (ret) > + return ret; > + > + long_mask = strtoul(cbm_mask, NULL, 16); > + > + ret = get_cache_size(core_id, 3, &cache_size); > + if (ret) > + return ret; > + printf("cache size :%lu\n", cache_size); > + > + count_of_bits = count_bits(long_mask); > + > + if (n < 1 || n > count_of_bits) { > + printf("Invalid input value for numbr_of_bits n!\n"); > + printf("Please Enter value in range 1 to %d\n", > count_of_bits); > + return -1; > + } > + > + struct resctrl_val_param param = { > + .resctrl_val = "cqm", > + .ctrlgrp = "c1", > + .mongrp = "m1", > + .cpu_no = core_id, > + .mum_resctrlfs = 0, > + .filename = RESULT_FILE_NAME, > + .mask = ~(long_mask << n) & long_mask, > + .span = cache_size * n / count_of_bits, > + .num_of_runs = 0, > + .setup = cqm_setup, > + }; > + > + if (strcmp(benchmark_cmd[0], "fill_buf") == 0) > + sprintf(benchmark_cmd[1], "%llu", param.span); > + > + remove(RESULT_FILE_NAME); > + > + ret = resctrl_val(benchmark_cmd, ¶m); > + if (ret) > + return ret; > + > + ret = check_results(¶m, n); > + if (ret) > + return ret; > + > + cqm_test_cleanup(); > + > + return 0; > +} > diff --git a/tools/testing/selftests/resctrl/fill_buf.c > b/tools/testing/selftests/resctrl/fill_buf.c > index d9950b5d068d..7c3579a3ef06 100644 > --- a/tools/testing/selftests/resctrl/fill_buf.c > +++ b/tools/testing/selftests/resctrl/fill_buf.c > @@ -78,54 +78,63 @@ static void *malloc_and_init_memory(size_t s) > return p; > } > > -static void fill_cache_read(unsigned char *start_ptr, unsigned char > *end_ptr) > +static void fill_one_span_read(unsigned char *start_ptr, unsigned char > *end_ptr) > { > - while (1) { > - unsigned char sum, *p; > - > - p = start_ptr; > - /* Read two chars in each cache line to stress cache */ > - while (p < (end_ptr - 1024)) { > - sum += p[0] + p[32] + p[64] + p[96] + p[128] + > - p[160] + p[192] + p[224] + p[256] + p[288] + > - p[320] + p[352] + p[384] + p[416] + p[448] + > - p[480] + p[512] + p[544] + p[576] + p[608] + > - p[640] + p[672] + p[704] + p[736] + p[768] + > - p[800] + p[832] + p[864] + p[896] + p[928] + > - p[960] + p[992]; > - p += 1024; > - } > + unsigned char sum, *p; > + > + sum = 0; > + p = start_ptr; > + while (p < end_ptr) { > + sum += *p; > + p += (CL_SIZE / 2); > } > } > > -static void fill_cache_write(unsigned char *start_ptr, unsigned char > *end_ptr) > +static > +void fill_one_span_write(unsigned char *start_ptr, unsigned char > *end_ptr) > { > - while (1) { > - while (start_ptr < end_ptr) { > - *start_ptr = '1'; > - start_ptr += (CL_SIZE / 2); > - } > - start_ptr = startptr; > + unsigned char *p; > + > + p = start_ptr; > + while (p < end_ptr) { > + *p = '1'; > + p += (CL_SIZE / 2); > } > } > > -static void > -fill_cache(unsigned long long buf_size, int malloc_and_init, > - int memflush, int op) > +static int fill_cache_read(unsigned char *start_ptr, unsigned char *end_ptr, > + char *resctrl_val) > +{ > + while (1) > + fill_one_span_read(start_ptr, end_ptr); > + > + return 0; > +} > + > +static int fill_cache_write(unsigned char *start_ptr, unsigned char > *end_ptr, > + char *resctrl_val) > +{ > + while (1) > + fill_one_span_write(start_ptr, end_ptr); > + > + return 0; > +} > + > +static int > +fill_cache(unsigned long long buf_size, int malloc_and_init, int memflush, > + int op, char *resctrl_val) > { > unsigned char *start_ptr, *end_ptr; > unsigned long long i; > + int ret; > > - if (malloc_and_init) { > + if (malloc_and_init) > start_ptr = malloc_and_init_memory(buf_size); > - printf("Started benchmark with memalign\n"); > - } else { > + else > start_ptr = malloc(buf_size); > - printf("Started benchmark with malloc\n"); > - } > > if (!start_ptr) > - return; > + return -1; > > startptr = start_ptr; > end_ptr = start_ptr + buf_size; > @@ -142,24 +151,29 @@ fill_cache(unsigned long long buf_size, int > malloc_and_init, > start_ptr = startptr; > > /* Flush the memory before using to avoid "cache hot pages" effect > */ > - if (memflush) { > + if (memflush) > mem_flush(start_ptr, buf_size); > - printf("Started benchmark with memflush\n"); > - } else { > - printf("Started benchmark *without* memflush\n"); > - } > > if (op == 0) > - fill_cache_read(start_ptr, end_ptr); > + ret = fill_cache_read(start_ptr, end_ptr, resctrl_val); > else > - fill_cache_write(start_ptr, end_ptr); > + ret = fill_cache_write(start_ptr, end_ptr, resctrl_val); > + > + if (ret) { > + printf("\n Errror in fill cache read/write...\n"); > + return -1; > + } > > free(startptr); > + > + return 0; > } > > -int run_fill_buf(int span, int malloc_and_init_memory, int memflush, int op) > +int run_fill_buf(unsigned long long span, int malloc_and_init_memory, > + int memflush, int op, char *resctrl_val) > { > - unsigned long long cache_size = span * MB; > + unsigned long long cache_size = span; > + int ret; > > /* set up ctrl-c handler */ > if (signal(SIGINT, ctrl_handler) == SIG_ERR) > @@ -167,9 +181,12 @@ int run_fill_buf(int span, int > malloc_and_init_memory, int memflush, int op) > if (signal(SIGHUP, ctrl_handler) == SIG_ERR) > printf("Failed to catch SIGHUP!\n"); > > - printf("Cache size in Bytes = %llu\n", cache_size); > - > - fill_cache(cache_size, malloc_and_init_memory, memflush, op); > + ret = fill_cache(cache_size, malloc_and_init_memory, memflush, op, > + resctrl_val); > + if (ret) { > + printf("\n Errror in fill cache\n"); > + return -1; > + } > > - return -1; > + return 0; > } > diff --git a/tools/testing/selftests/resctrl/mba_test.c > b/tools/testing/selftests/resctrl/mba_test.c > index 7a5d869e5382..66be852d737f 100644 > --- a/tools/testing/selftests/resctrl/mba_test.c > +++ b/tools/testing/selftests/resctrl/mba_test.c > @@ -57,6 +57,7 @@ static void show_mba_info(unsigned long *bw_imc, > unsigned long *bw_resc) > { > int allocation, failed = 0, runs; > > + printf("\nResults are displayed in (MB)\n"); > /* Memory bandwidth from 100% down to 10% */ > for (allocation = 0; allocation < ALLOCATION_MAX / > ALLOCATION_STEP; > allocation++) { > @@ -159,7 +160,7 @@ int mba_schemata_change(int core_id, char > *bw_report, char **benchmark_cmd) > > remove(RESULT_FILE_NAME); > > - ret = membw_val(benchmark_cmd, ¶m); > + ret = resctrl_val(benchmark_cmd, ¶m); > if (ret) > return ret; > > diff --git a/tools/testing/selftests/resctrl/mbm_test.c > b/tools/testing/selftests/resctrl/mbm_test.c > index fc1b8bab1c71..ce3eab15328e 100644 > --- a/tools/testing/selftests/resctrl/mbm_test.c > +++ b/tools/testing/selftests/resctrl/mbm_test.c > @@ -36,6 +36,7 @@ show_bw_info(unsigned long *bw_imc, unsigned long > *bw_resc, int span) > avg_bw_resc = sum_bw_resc / 4; > avg_diff = avg_bw_resc - avg_bw_imc; > > + printf("\nResults are displayed in (MB)\n"); > printf("\nSpan (MB): %d \t", span); > printf("avg_bw_imc: %lu\t", avg_bw_imc); > printf("avg_bw_resc: %lu\t", avg_bw_resc); > @@ -131,7 +132,7 @@ int mbm_bw_change(int span, int core_id, char > *bw_report, char **benchmark_cmd) > > remove(RESULT_FILE_NAME); > > - ret = membw_val(benchmark_cmd, ¶m); > + ret = resctrl_val(benchmark_cmd, ¶m); > if (ret) > return ret; > > diff --git a/tools/testing/selftests/resctrl/resctrl.h > b/tools/testing/selftests/resctrl/resctrl.h > index fce01c827d81..b847ec972e77 100644 > --- a/tools/testing/selftests/resctrl/resctrl.h > +++ b/tools/testing/selftests/resctrl/resctrl.h > @@ -16,11 +16,18 @@ > #include <sys/ioctl.h> > #include <sys/mount.h> > #include <sys/types.h> > +#include <sys/select.h> > #include <asm/unistd.h> > #include <linux/perf_event.h> > +#include <sys/time.h> > +#include <math.h> > +#include <sys/wait.h> > +#include <sys/eventfd.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" > > #define PARENT_EXIT(err_msg) \ > do { \ > @@ -46,18 +53,24 @@ struct resctrl_val_param { > char ctrlgrp[64]; > char mongrp[64]; > int cpu_no; > - int span; > + unsigned long long span; > int mum_resctrlfs; > char filename[64]; > char *bw_report; > + unsigned long mask; > + int num_of_runs; > int (*setup)(int num, ...); > + > }; > > pid_t bm_pid, ppid; > +extern char cbm_mask[256]; > +extern unsigned long long_mask; > +extern char llc_occup_path[1024]; > > int remount_resctrlfs(bool mum_resctrlfs); > int umount_resctrlfs(void); > -char get_sock_num(int cpu_no); > +int get_sock_num(int cpu_no, char *sock_num); > int validate_bw_report_request(char *bw_report); > int validate_resctrl_feature_request(char *resctrl_val); > int taskset_benchmark(pid_t bm_pid, int cpu_no); > @@ -68,12 +81,21 @@ 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(int span, int malloc_and_init_memory, int memflush, int > op); > -int membw_val(char **benchmark_cmd, struct resctrl_val_param *param); > +int run_fill_buf(unsigned long long span, int malloc_and_init_memory, > + int memflush, int op, char *resctrl_val); > +int resctrl_val(char **benchmark_cmd, struct resctrl_val_param *param); > int mbm_bw_change(int span, int core_id, char *bw_report, char > **benchmark_cmd); > void tests_cleanup(void); > void mbm_test_cleanup(void); > int mba_schemata_change(int core_id, char *bw_report, char > **benchmark_cmd); > void mba_test_cleanup(void); > +int get_cbm_mask(char *cache_type); > +int get_cache_size(int cpu_no, int cache_num, unsigned long *cache_size); > +void ctrlc_handler(int signum, siginfo_t *info, void *ptr); > +int cqm_resctrl_val(int core_id, int n, char **benchmark_cmd); > +unsigned int count_bits(unsigned long n); > +void cqm_test_cleanup(void); > +int get_core_sibling(int cpu_no); > +int measure_cache_vals(struct resctrl_val_param *param, int bm_pid); > > #endif /* RESCTRL_H */ > diff --git a/tools/testing/selftests/resctrl/resctrl_tests.c > b/tools/testing/selftests/resctrl/resctrl_tests.c > index e4d00fb63769..035929f18696 100644 > --- a/tools/testing/selftests/resctrl/resctrl_tests.c > +++ b/tools/testing/selftests/resctrl/resctrl_tests.c > @@ -14,15 +14,14 @@ > #define BENCHMARK_ARGS 64 > #define BENCHMARK_ARG_SIZE 64 > > -int ben_count; > - > static void cmd_help(void) > { > - printf("usage: resctrl_tests [-h] [-b \"benchmark_cmd [options]\"] [- > t test list]\n"); > - printf("\t-b benchmark_cmd [options]: run specified benchmark\n"); > + printf("usage: resctrl_tests [-h] [-b \"benchmark_cmd [options]\"] [- > t test list] [-n no_of_bits]\n"); > + printf("\t-b benchmark_cmd [options]: run specified benchmark for > MBM, MBA and CQM"); > printf("\t default benchmark is builtin fill_buf\n"); > printf("\t-t test list: run tests specified in the test list, "); > - printf("e.g. -t mbm,mba\n"); > + printf("e.g. -t mbm, mba, cqm\n"); > + printf("\t-n no_of_bits: run cache tests using specified no of bits in > cache bit mask\n"); > printf("\t-h: help\n"); > } > > @@ -30,17 +29,30 @@ void tests_cleanup(void) > { > mbm_test_cleanup(); > mba_test_cleanup(); > + cqm_test_cleanup(); > } > > int main(int argc, char **argv) > { > char > benchmark_cmd_area[BENCHMARK_ARGS][BENCHMARK_ARG_SIZE]; > - int res, c, core_id = 0, span = 250, argc_new = argc, i; > + int res, c, core_id = 1, span = 250, argc_new = argc, i, no_of_bits = 5; > + int ben_count, ben_ind; > bool has_ben = false, mbm_test = true, mba_test = true; > + bool cqm_test = true; > char *benchmark_cmd[BENCHMARK_ARGS]; > char bw_report[64], bm_type[64]; > > - while ((c = getopt(argc_new, argv, "ht:b:")) != -1) { > + for (int i = 0; i < argc; i++) { This declaration here is causing following errors. resctrl_tests.c: In function ‘main’: resctrl_tests.c:46:11: error: redeclaration of ‘i’ with no linkage for (int i = 0; i < argc; i++) { ^ resctrl_tests.c:39:56: note: previous declaration of ‘i’ was here int res, c, core_id = 1, span = 250, argc_new = argc, i, no_of_bits = 5; ^ resctrl_tests.c:46:2: error: ‘for’ loop initial declarations are only allowed in C99 mode for (int i = 0; i < argc; i++) { ^ resctrl_tests.c:46:2: note: use option -std=c99 or -std=gnu99 to compile your code > + if (strcmp(argv[i], "-b") == 0) { > + ben_ind = i + 1; > + ben_count = argc - ben_ind; > + argc_new = ben_ind - 1; > + has_ben = 1; > + break; > + } > + } > + > + while ((c = getopt(argc_new, argv, "ht:n:p:")) != -1) { > char *token; > > switch (c) { > @@ -49,11 +61,14 @@ int main(int argc, char **argv) > > mbm_test = false; > mba_test = false; > + cqm_test = false; > while (token) { > if (!strcmp(token, "mbm")) { > mbm_test = true; > } else if (!strcmp(token, "mba")) { > mba_test = true; > + } else if (!strcmp(token, "cqm")) { > + cqm_test = true; > } else { > printf("invalid argument\n"); > > @@ -62,22 +77,11 @@ int main(int argc, char **argv) > token = strtok(NULL, ":\t"); > } > break; > - case 'b': > - /* Extract benchmark command from command line. > */ > - token = strtok(optarg, " "); > - i = 0; > - while (token) { > - benchmark_cmd[i] = > benchmark_cmd_area[i]; > - strcpy(benchmark_cmd[i++], token); > - if (i >= BENCHMARK_ARGS) { > - printf("Too many benchmark > args\n"); > - > - return -1; > - } > - token = strtok(NULL, " "); > - } > - benchmark_cmd[i] = NULL; > - has_ben = true; > + case 'n': > + no_of_bits = atoi(optarg); > + break; > + case 'p': > + core_id = atoi(optarg); > break; > case 'h': > cmd_help(); > @@ -101,16 +105,26 @@ int main(int argc, char **argv) > return errno; > } > > - if (!has_ben) { > + if (has_ben) { > + /* Extract benchmark command from command line. */ > + for (int i = ben_ind; i < argc; i++) { resctrl_tests.c:114:3: error: ‘for’ loop initial declarations are only allowed in C99 mode for (int i = ben_ind; i < argc; i++) { ^ make: *** [*.o] Error 1 > + benchmark_cmd[i - ben_ind] = > benchmark_cmd_area[i]; > + sprintf(benchmark_cmd[i - ben_ind], "%s", argv[i]); > + } > + benchmark_cmd[ben_count] = > benchmark_cmd_area[ben_count]; > + sprintf(benchmark_cmd[ben_count], "%s", "NULL"); > + } else { > /* If no benchmark is given by "-b" argument, use fill_buf. */ > - for (i = 0; i < 5; i++) > + for (i = 0; i < 6; i++) > benchmark_cmd[i] = benchmark_cmd_area[i]; > + > strcpy(benchmark_cmd[0], "fill_buf"); > sprintf(benchmark_cmd[1], "%d", span); > strcpy(benchmark_cmd[2], "1"); > strcpy(benchmark_cmd[3], "1"); > strcpy(benchmark_cmd[4], "0"); > - benchmark_cmd[5] = NULL; > + strcpy(benchmark_cmd[5], ""); > + benchmark_cmd[6] = NULL; > } > > sprintf(bw_report, "reads"); > @@ -118,18 +132,32 @@ int main(int argc, char **argv) > > if (mbm_test) { > printf("\nMBM BW Change Starting..\n"); > + if (!has_ben) > + sprintf(benchmark_cmd[5], "%s", "mbm"); > res = mbm_bw_change(span, core_id, bw_report, > benchmark_cmd); > if (res) > printf("Error in running tests for mbm bw > change!\n"); > + mbm_test_cleanup(); > } > > if (mba_test) { > printf("\nMBA Schemata Change Starting..\n"); > if (!has_ben) > - sprintf(benchmark_cmd[1], "%d", span); > + sprintf(benchmark_cmd[5], "%s", "mba"); > res = mba_schemata_change(core_id, bw_report, > benchmark_cmd); > if (res) > printf("Error in tests for mba-change-schemata!\n"); > + mba_test_cleanup(); > + } > + > + if (cqm_test) { > + printf("\nCQM Test Starting..\n"); > + if (!has_ben) > + sprintf(benchmark_cmd[5], "%s", "cqm"); > + res = cqm_resctrl_val(core_id, no_of_bits, benchmark_cmd); > + if (res) > + printf("Error in CQM test!\n"); > + cqm_test_cleanup(); > } > > return 0; > diff --git a/tools/testing/selftests/resctrl/resctrl_val.c > b/tools/testing/selftests/resctrl/resctrl_val.c > index fa77af5a5b57..eb7d5f0620e2 100644 > --- a/tools/testing/selftests/resctrl/resctrl_val.c > +++ b/tools/testing/selftests/resctrl/resctrl_val.c > @@ -11,7 +11,6 @@ > */ > #include "resctrl.h" > > -#define MB (1024 * 1024) > #define UNCORE_IMC "uncore_imc" > #define READ_FILE_NAME "events/cas_count_read" > #define WRITE_FILE_NAME "events/cas_count_write" > @@ -33,6 +32,18 @@ > #define MBM_LOCAL_BYTES_PATH \ > "%s/mon_data/mon_L3_0%c/mbm_local_bytes" > > +#define CON_MON_LCC_OCCUP_PATH \ > + "%s/%s/mon_groups/%s/mon_data/mon_L3_0%c/llc_occupancy" > + > +#define CON_LCC_OCCUP_PATH \ > + "%s/%s/mon_data/mon_L3_0%c/llc_occupancy" > + > +#define MON_LCC_OCCUP_PATH \ > + "%s/mon_groups/%s/mon_data/mon_L3_0%c/llc_occupancy" > + > +#define LCC_OCCUP_PATH \ > + "%s/mon_data/mon_L3_0%c/llc_occupancy" > + > struct membw_read_format { > __u64 value; /* The value of the event */ > __u64 time_enabled; /* if PERF_FORMAT_TOTAL_TIME_ENABLED > */ > @@ -207,12 +218,12 @@ static int read_from_imc_dir(char *imc_dir, int > count) > * A config again has two parts, event and umask. > * Enumerate all these details into an array of structures. > * > - * Return: >= 0 on success. < 0 on failure. > + * Return: > 0 on success. <= 0 on failure. > */ > static int num_of_imcs(void) > { > unsigned int count = 0; > - char imc_dir[1024]; > + char imc_dir[512]; > struct dirent *ep; > int ret; > DIR *dp; > @@ -381,9 +392,10 @@ static void initialize_mem_bw_resctrl(const char > *ctrlgrp, const char *mongrp, > int cpu_no, char *resctrl_val) > { > char sock_num; > + int ret; > > - sock_num = get_sock_num(cpu_no); > - if (sock_num < 0) > + ret = get_sock_num(cpu_no, &sock_num); > + if (ret < 0) > return; > > if (strcmp(resctrl_val, "mbm") == 0) > @@ -433,16 +445,6 @@ static unsigned long get_mem_bw_resctrl(void) > > pid_t bm_pid, ppid; > > -static void ctrlc_handler(int signum, siginfo_t *info, void *ptr) > -{ > - kill(bm_pid, SIGKILL); > - umount_resctrlfs(); > - tests_cleanup(); > - printf("Ending\n\n"); > - > - exit(EXIT_SUCCESS); > -} > - > /* > * print_results_bw: the memory bandwidth results are stored in a file > * @filename: file that stores the results > @@ -481,6 +483,42 @@ static int print_results_bw(char *filename, int > bm_pid, float bw_imc, > return 0; > } > > +static void set_cqm_path(const char *ctrlgrp, const char *mongrp, char > sock_num) > +{ > + if (strlen(ctrlgrp) && strlen(mongrp)) > + sprintf(llc_occup_path, CON_MON_LCC_OCCUP_PATH, > RESCTRL_PATH, > + ctrlgrp, mongrp, sock_num); > + else if (!strlen(ctrlgrp) && strlen(mongrp)) > + sprintf(llc_occup_path, MON_LCC_OCCUP_PATH, > RESCTRL_PATH, > + mongrp, sock_num); > + else if (strlen(ctrlgrp) && !strlen(mongrp)) > + sprintf(llc_occup_path, CON_LCC_OCCUP_PATH, > RESCTRL_PATH, > + ctrlgrp, sock_num); > + else if (!strlen(ctrlgrp) && !strlen(mongrp)) > + sprintf(llc_occup_path, LCC_OCCUP_PATH, > RESCTRL_PATH, sock_num); > +} > + > +/* > + * initialize_llc_occu_resctrl: Appropriately populate "llc_occup_path" > + * @ctrlgrp: Name of the control monitor group > (con_mon grp) > + * @mongrp: Name of the monitor group (mon grp) > + * @cpu_no: CPU number that the benchmark PID is > binded to > + * @resctrl_val: Resctrl feature (Eg: cat, cqm.. etc) > + */ > +static void initialize_llc_occu_resctrl(const char *ctrlgrp, const char > *mongrp, > + int cpu_no, char *resctrl_val) > +{ > + char sock_num; > + int ret; > + > + ret = get_sock_num(cpu_no, &sock_num); > + if (ret < 0) > + return; > + > + if (strcmp(resctrl_val, "cqm") == 0) > + set_cqm_path(ctrlgrp, mongrp, sock_num); > +} > + > static int > measure_vals(struct resctrl_val_param *param, unsigned long > *bw_resc_start) > { > @@ -513,28 +551,24 @@ measure_vals(struct resctrl_val_param *param, > unsigned long *bw_resc_start) > } > > /* > - * membw_val: execute benchmark and measure memory > bandwidth on > + * resctrl_val: execute benchmark and measure memory > bandwidth on > * the benchmark > * @benchmark_cmd: benchmark command and its arguments > - * @param: parameters passed to membw_val() > + * @param: parameters passed to resctrl_val() > * > * Return: 0 on success. non-zero on failure. > */ > -int membw_val(char **benchmark_cmd, struct resctrl_val_param *param) > +int resctrl_val(char **benchmark_cmd, struct resctrl_val_param *param) > { > int ret = 0, pipefd[2], pipe_message = 0; > char *resctrl_val = param->resctrl_val; > unsigned long bw_resc_start = 0; > struct sigaction sigact; > union sigval value; > - FILE *fp; > > if (strcmp(param->filename, "") == 0) > sprintf(param->filename, "stdio"); > > - if (strcmp(param->bw_report, "") == 0) > - param->bw_report = "total"; > - > ret = validate_resctrl_feature_request(resctrl_val); > if (ret) > return ret; > @@ -556,21 +590,6 @@ int membw_val(char **benchmark_cmd, struct > resctrl_val_param *param) > */ > ppid = getpid(); > > - /* File based synchronization between parent and child */ > - fp = fopen("sig", "w"); > - if (!fp) { > - perror("Failed to open sig file"); > - > - return -1; > - } > - if (fprintf(fp, "%d\n", 0) <= 0) { > - perror("Unable to establish sync bw parent & child"); > - fclose(fp); > - > - return -1; > - } > - fclose(fp); > - > if (pipe(pipefd)) { > perror("Unable to create pipe"); > > @@ -652,7 +671,9 @@ int membw_val(char **benchmark_cmd, struct > resctrl_val_param *param) > > initialize_mem_bw_resctrl(param->ctrlgrp, param->mongrp, > param->cpu_no, resctrl_val); > - } > + } else if (strcmp(resctrl_val, "cqm") == 0) > + initialize_llc_occu_resctrl(param->ctrlgrp, param->mongrp, > + param->cpu_no, resctrl_val); > > /* Parent waits for child to be ready. */ > close(pipefd[1]); > @@ -672,7 +693,8 @@ int membw_val(char **benchmark_cmd, struct > resctrl_val_param *param) > > /* Test runs until the callback setup() tells the test to stop. */ > while (1) { > - if (strcmp(resctrl_val, "mbm") == 0) { > + if ((strcmp(resctrl_val, "mbm") == 0) || > + (strcmp(resctrl_val, "mba") == 0)) { > ret = param->setup(1, param); > if (ret) { > ret = 0; > @@ -682,14 +704,14 @@ int membw_val(char **benchmark_cmd, struct > resctrl_val_param *param) > ret = measure_vals(param, &bw_resc_start); > if (ret) > break; > - } else if ((strcmp(resctrl_val, "mba") == 0)) { > + } else if (strcmp(resctrl_val, "cqm") == 0) { > ret = param->setup(1, param); > if (ret) { > ret = 0; > break; > } > - > - ret = measure_vals(param, &bw_resc_start); > + sleep(1); > + ret = measure_cache_vals(param, bm_pid); > if (ret) > break; > } else { > diff --git a/tools/testing/selftests/resctrl/resctrlfs.c > b/tools/testing/selftests/resctrl/resctrlfs.c > index 9d9962947c9c..9fc27ae68582 100644 > --- a/tools/testing/selftests/resctrl/resctrlfs.c > +++ b/tools/testing/selftests/resctrl/resctrlfs.c > @@ -13,7 +13,11 @@ > > #define RESCTRL_MBM "L3 monitoring detected" > #define RESCTRL_MBA "MB allocation detected" > -#define MAX_RESCTRL_FEATURES 2 > +#define RESCTRL_CQM "L3 monitoring detected" > +#define MAX_RESCTRL_FEATURES 4 > +#define CORE_SIBLINGS_PATH "/sys/bus/cpu/devices/cpu" > + > +char cbm_mask[256]; > > /* > * remount_resctrlfs - Remount resctrl FS at /sys/fs/resctrl > @@ -58,7 +62,7 @@ int remount_resctrlfs(bool mum_resctrlfs) > > return errno; > } > - printf("Remount: done!\n"); > + printf("umount: done!\n"); > } else { > printf("Mounted already. Not remounting!\n"); > > @@ -89,12 +93,13 @@ int umount_resctrlfs(void) > /* > * get_sock_num - Get socket number for a specified CPU > * @cpu_no: CPU number > + * @sock_num: pointer to socket_number > * > * Return: >= 0 on success, < 0 on failure. > */ > -char get_sock_num(int cpu_no) > +int get_sock_num(int cpu_no, char *sock_num) > { > - char sock_num, phys_pkg_path[1024]; > + char phys_pkg_path[1024]; > FILE *fp; > > sprintf(phys_pkg_path, "%s%d/topology/physical_package_id", > @@ -105,7 +110,7 @@ char get_sock_num(int cpu_no) > > return -1; > } > - if (fscanf(fp, "%c", &sock_num) <= 0) { > + if (fscanf(fp, "%c", sock_num) <= 0) { > perror("Could not get socket number"); > fclose(fp); > > @@ -113,7 +118,135 @@ char get_sock_num(int cpu_no) > } > fclose(fp); > > - return sock_num; > + return 0; > +} > + > +/* > + * get_cache_size - Get cache size for a specified CPU > + * @cpu_no: CPU number > + * @cache_num: Cache level 2 for L2, 3 for L3 > + * @cache_size: pointer to cache_size > + * > + * Return: = 0 on success, < 0 on failure. > + */ > +int get_cache_size(int cpu_no, int cache_num, unsigned long *cache_size) > +{ > + char cache_path[1024], cache_str[64]; > + FILE *fp; > + int length, i; > + > + sprintf(cache_path, > "/sys/bus/cpu/devices/cpu%d/cache/index%d/size", > + cpu_no, cache_num); > + fp = fopen(cache_path, "r"); > + if (!fp) { > + perror("Failed to open cache size"); > + > + return -1; > + } > + if (fscanf(fp, "%s", cache_str) <= 0) { > + perror("Could not get cache_size"); > + fclose(fp); > + > + return -1; > + } > + fclose(fp); > + > + length = (int)strlen(cache_str); > + > + *cache_size = 0; > + > + for (i = 0; i < length; i++) { > + if ((cache_str[i] >= '0') && (cache_str[i] <= '9')) > + > + *cache_size = *cache_size * 10 + (cache_str[i] - '0'); > + > + else if (cache_str[i] == 'K') > + > + *cache_size = *cache_size * 1024; > + > + else if (cache_str[i] == 'M') > + > + *cache_size = *cache_size * 1024 * 1024; > + > + else > + break; > + } > + > + return 0; > +} > + > +/* > + * get_cbm_mask - Get cbm mask for given cache > + * @cache_type: Cache level L2/L3 > + * > + * Mask is stored in cbm_mask which is global variable. > + * > + * Return: = 0 on success, < 0 on failure. > + */ > +int get_cbm_mask(char *cache_type) > +{ > + char cbm_mask_path[1024]; > + FILE *fp; > + > + sprintf(cbm_mask_path, "%s/%s/cbm_mask", CBM_MASK_PATH, > cache_type); > + > + fp = fopen(cbm_mask_path, "r"); > + if (!fp) { > + perror("Failed to open cache level"); > + > + return -1; > + } > + if (fscanf(fp, "%s", cbm_mask) <= 0) { > + perror("Could not get max cbm_mask"); > + fclose(fp); > + > + return -1; > + } > + fclose(fp); > + > + return 0; > +} > + > +/* > + * get_core_sibling - Get sibling core id from the same socket for given CPU > + * @cpu_no: CPU number > + * > + * Return: > 0 on success, < 0 on failure. > + */ > +int get_core_sibling(int cpu_no) > +{ > + char core_siblings_path[1024], cpu_list_str[64]; > + int sibling_core_id = -1; > + FILE *fp; > + > + sprintf(core_siblings_path, "%s%d/topology/core_siblings_list", > + CORE_SIBLINGS_PATH, cpu_no); > + > + fp = fopen(core_siblings_path, "r"); > + if (!fp) { > + perror("Failed to open core siblings path"); > + > + return -1; > + } > + if (fscanf(fp, "%s", cpu_list_str) <= 0) { > + perror("Could not get core_siblings list"); > + fclose(fp); > + > + return -1; > + } > + fclose(fp); > + > + char *token = strtok(cpu_list_str, "-,"); > + > + while (token) { > + sibling_core_id = atoi(token); > + /* Skipping core 0 as we don't want to run test on core 0 */ > + if (sibling_core_id != 0) > + break; > + token = strtok(NULL, "-,"); > + } > + > + return sibling_core_id; > } > > /* > @@ -152,8 +285,10 @@ int taskset_benchmark(pid_t bm_pid, int cpu_no) > */ > void run_benchmark(int signum, siginfo_t *info, void *ucontext) > { > - int span, operation, ret; > + unsigned long long buffer_span; > + int span, operation, ret, malloc_and_init_memory, memflush; > char **benchmark_cmd; > + char resctrl_val[64]; > FILE *fp; > > benchmark_cmd = info->si_ptr; > @@ -169,8 +304,18 @@ void run_benchmark(int signum, siginfo_t *info, > void *ucontext) > if (strcmp(benchmark_cmd[0], "fill_buf") == 0) { > /* Execute default fill_buf benchmark */ > span = atoi(benchmark_cmd[1]); > + malloc_and_init_memory = atoi(benchmark_cmd[2]); > + memflush = atoi(benchmark_cmd[3]); > operation = atoi(benchmark_cmd[4]); > - if (run_fill_buf(span, 1, 1, operation)) > + sprintf(resctrl_val, "%s", benchmark_cmd[5]); > + > + if (strcmp(resctrl_val, "cqm") != 0) > + buffer_span = span * MB; > + else > + buffer_span = span; > + > + if (run_fill_buf(buffer_span, malloc_and_init_memory, > memflush, > + operation, resctrl_val)) > fprintf(stderr, "Error in running fill buffer\n"); > } else { > /* Execute specified benchmark */ > @@ -197,6 +342,14 @@ static int create_grp(const char *grp_name, char > *grp, const char *parent_grp) > struct dirent *ep; > DIR *dp; > > + /* > + * At this point, we are guaranteed to have resctrl FS mounted and if > + * length of grp_name == 0, it means, user wants to use root > con_mon > + * grp, so do nothing > + */ > + if (strlen(grp_name) == 0) > + return 0; > + > /* Check if requested grp exists or not */ > dp = opendir(parent_grp); > if (dp) { > @@ -238,7 +391,6 @@ static int write_pid_to_tasks(char *tasks, pid_t pid) > fclose(fp); > > return -1; > - > } > fclose(fp); > > @@ -263,11 +415,11 @@ static int write_pid_to_tasks(char *tasks, pid_t pid) > int write_bm_pid_to_resctrl(pid_t bm_pid, char *ctrlgrp, char *mongrp, > char *resctrl_val) > { > - char controlgroup[256], monitorgroup[256], monitorgroup_p[256]; > - char tasks[256]; > + char controlgroup[128], monitorgroup[512], monitorgroup_p[256]; > + char tasks[1024]; > int ret; > > - if (ctrlgrp) > + if (strlen(ctrlgrp)) > sprintf(controlgroup, "%s/%s", RESCTRL_PATH, ctrlgrp); > else > sprintf(controlgroup, "%s", RESCTRL_PATH); > @@ -281,9 +433,10 @@ int write_bm_pid_to_resctrl(pid_t bm_pid, char > *ctrlgrp, char *mongrp, > if (ret) > return ret; > > - /* Create mon grp and write pid into it for "mbm" test */ > - if ((strcmp(resctrl_val, "mbm") == 0)) { > - if (mongrp) { > + /* Create mon grp and write pid into it for "mbm" and "cqm" test */ > + if ((strcmp(resctrl_val, "cqm") == 0) || > + (strcmp(resctrl_val, "mbm") == 0)) { > + if (strlen(mongrp)) { > sprintf(monitorgroup_p, "%s/mon_groups", > controlgroup); > sprintf(monitorgroup, "%s/%s", monitorgroup_p, > mongrp); > ret = create_grp(mongrp, monitorgroup, > monitorgroup_p); > @@ -319,23 +472,31 @@ int write_schemata(char *ctrlgrp, char *schemata, > int cpu_no, char *resctrl_val) > { > char sock_num, controlgroup[1024], schema[1024]; > FILE *fp; > + int ret; > > - if (strcmp(resctrl_val, "mba") == 0) { > + if ((strcmp(resctrl_val, "mba") == 0) || > + (strcmp(resctrl_val, "cqm") == 0)) { > if (!schemata) { > printf("Schemata empty, so not updating\n"); > > return 0; > } > - sock_num = get_sock_num(cpu_no); > - if (sock_num < 0) > + ret = get_sock_num(cpu_no, &sock_num); > + if (ret < 0) > return -1; > > - if (ctrlgrp) > + if (strlen(ctrlgrp) != 0) > sprintf(controlgroup, "%s/%s/schemata", > RESCTRL_PATH, > ctrlgrp); > else > sprintf(controlgroup, "%s/schemata", > RESCTRL_PATH); > - sprintf(schema, "%s%c%c%s", "MB:", sock_num, '=', > schemata); > + > + if (!strcmp(resctrl_val, "cqm")) > + sprintf(schema, "%s%c%c%s", "L3:", sock_num, '=', > + schemata); > + if (strcmp(resctrl_val, "mba") == 0) > + sprintf(schema, "%s%c%c%s", "MB:", sock_num, '=', > + schemata); > > fp = fopen(controlgroup, "w"); > if (!fp) { > @@ -352,7 +513,7 @@ int write_schemata(char *ctrlgrp, char *schemata, int > cpu_no, char *resctrl_val) > } > fclose(fp); > > - printf("Write schemata to resctrl FS: done!\n"); > + printf("Write schemata with %s to resctrl FS: done!\n", > schema); > } > > return 0; > @@ -366,9 +527,9 @@ int write_schemata(char *ctrlgrp, char *schemata, int > cpu_no, char *resctrl_val) > */ > int validate_resctrl_feature_request(char *resctrl_val) > { > - int resctrl_features_supported[MAX_RESCTRL_FEATURES] = {0, 0}; > + int resctrl_features_supported[MAX_RESCTRL_FEATURES] = {0, 0, 0, > 0}; > const char *resctrl_features_list[MAX_RESCTRL_FEATURES] = { > - "mbm", "mba"}; > + "mbm", "mba", "cqm"}; > int i, valid_resctrl_feature = -1; > char line[1024]; > FILE *fp; > @@ -409,6 +570,8 @@ int validate_resctrl_feature_request(char > *resctrl_val) > resctrl_features_supported[0] = 1; > if ((strstr(line, RESCTRL_MBA)) != NULL) > resctrl_features_supported[1] = 1; > + if ((strstr(line, RESCTRL_CQM)) != NULL) > + resctrl_features_supported[3] = 1; > } > fclose(fp); > > @@ -452,3 +615,25 @@ int perf_event_open(struct perf_event_attr > *hw_event, pid_t pid, int cpu, > group_fd, flags); > return ret; > } > + > +void ctrlc_handler(int signum, siginfo_t *info, void *ptr) > +{ > + kill(bm_pid, SIGKILL); > + umount_resctrlfs(); > + tests_cleanup(); > + printf("Ending\n\n"); > + > + exit(EXIT_SUCCESS); > +} > + > +unsigned int count_bits(unsigned long n) > +{ > + unsigned int count = 0; > + > + while (n) { > + count += n & 1; > + n >>= 1; > + } > + > + return count; > +} > -- > 2.19.1