/*
 * builtin-bench.c
 *
 * General benchmarking collections provided by perf
 *
 * Copyright (C) 2009, Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
 */

/*
 * Available benchmark collection list:
 *
 *  sched ... scheduler and IPC performance
 *  mem   ... memory access performance
 *  numa  ... NUMA scheduling and MM performance
 *  futex ... Futex performance
 */
#include "perf.h"
#include "util/util.h"
#include <subcmd/parse-options.h>
#include "builtin.h"
#include "bench/bench.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/prctl.h>

typedef int (*bench_fn_t)(int argc, const char **argv, const char *prefix);

struct bench {
        const char      *name;
        const char      *summary;
        bench_fn_t      fn;
};

#ifdef HAVE_LIBNUMA_SUPPORT
static struct bench numa_benchmarks[] = {
        { "mem",        "Benchmark for NUMA workloads",                 bench_numa              },
        { "all",        "Run all NUMA benchmarks",                      NULL                    },
        { NULL,         NULL,                                           NULL                    }
};
#endif

static struct bench sched_benchmarks[] = {
        { "messaging",  "Benchmark for scheduling and IPC",             bench_sched_messaging   },
        { "pipe",       "Benchmark for pipe() between two processes",   bench_sched_pipe        },
        { "all",        "Run all scheduler benchmarks",         NULL                    },
        { NULL,         NULL,                                           NULL                    }
};

static struct bench mem_benchmarks[] = {
        { "memcpy",     "Benchmark for memcpy() functions",             bench_mem_memcpy        },
        { "memset",     "Benchmark for memset() functions",             bench_mem_memset        },
        { "all",        "Run all memory access benchmarks",             NULL                    },
        { NULL,         NULL,                                           NULL                    }
};

static struct bench futex_benchmarks[] = {
        { "hash",       "Benchmark for futex hash table",               bench_futex_hash        },
        { "wake",       "Benchmark for futex wake calls",               bench_futex_wake        },
        { "wake-parallel", "Benchmark for parallel futex wake calls",   bench_futex_wake_parallel },
        { "requeue",    "Benchmark for futex requeue calls",            bench_futex_requeue     },
        /* pi-futexes */
        { "lock-pi",    "Benchmark for futex lock_pi calls",            bench_futex_lock_pi     },
        { "all",        "Run all futex benchmarks",                     NULL                    },
        { NULL,         NULL,                                           NULL                    }
};

struct collection {
        const char      *name;
        const char      *summary;
        struct bench    *benchmarks;
};

static struct collection collections[] = {
        { "sched",      "Scheduler and IPC benchmarks",                 sched_benchmarks        },
        { "mem",        "Memory access benchmarks",                     mem_benchmarks          },
#ifdef HAVE_LIBNUMA_SUPPORT
        { "numa",       "NUMA scheduling and MM benchmarks",            numa_benchmarks         },
#endif
        {"futex",       "Futex stressing benchmarks",                   futex_benchmarks        },
        { "all",        "All benchmarks",                               NULL                    },
        { NULL,         NULL,                                           NULL                    }
};

/* Iterate over all benchmark collections: */
#define for_each_collection(coll) \
        for (coll = collections; coll->name; coll++)

/* Iterate over all benchmarks within a collection: */
#define for_each_bench(coll, bench) \
        for (bench = coll->benchmarks; bench && bench->name; bench++)

static void dump_benchmarks(struct collection *coll)
{
        struct bench *bench;

        printf("\n        # List of available benchmarks for collection '%s':\n\n", coll->name);

        for_each_bench(coll, bench)
                printf("%14s: %s\n", bench->name, bench->summary);

        printf("\n");
}

static const char *bench_format_str;

/* Output/formatting style, exported to benchmark modules: */
int bench_format = BENCH_FORMAT_DEFAULT;
unsigned int bench_repeat = 10; /* default number of times to repeat the run */

static const struct option bench_options[] = {
        OPT_STRING('f', "format", &bench_format_str, "default|simple", "Specify the output formatting style"),
        OPT_UINTEGER('r', "repeat",  &bench_repeat,   "Specify amount of times to repeat the run"),
        OPT_END()
};

static const char * const bench_usage[] = {
        "perf bench [<common options>] <collection> <benchmark> [<options>]",
        NULL
};

static void print_usage(void)
{
        struct collection *coll;
        int i;

        printf("Usage: \n");
        for (i = 0; bench_usage[i]; i++)
                printf("\t%s\n", bench_usage[i]);
        printf("\n");

        printf("        # List of all available benchmark collections:\n\n");

        for_each_collection(coll)
                printf("%14s: %s\n", coll->name, coll->summary);
        printf("\n");
}

static int bench_str2int(const char *str)
{
        if (!str)
                return BENCH_FORMAT_DEFAULT;

        if (!strcmp(str, BENCH_FORMAT_DEFAULT_STR))
                return BENCH_FORMAT_DEFAULT;
        else if (!strcmp(str, BENCH_FORMAT_SIMPLE_STR))
                return BENCH_FORMAT_SIMPLE;

        return BENCH_FORMAT_UNKNOWN;
}

/*
 * Run a specific benchmark but first rename the running task's ->comm[]
 * to something meaningful:
 */
static int run_bench(const char *coll_name, const char *bench_name, bench_fn_t fn,
                     int argc, const char **argv, const char *prefix)
{
        int size;
        char *name;
        int ret;

        size = strlen(coll_name) + 1 + strlen(bench_name) + 1;

        name = zalloc(size);
        BUG_ON(!name);

        scnprintf(name, size, "%s-%s", coll_name, bench_name);

        prctl(PR_SET_NAME, name);
        argv[0] = name;

        ret = fn(argc, argv, prefix);

        free(name);

        return ret;
}

static void run_collection(struct collection *coll)
{
        struct bench *bench;
        const char *argv[2];

        argv[1] = NULL;
        /*
         * TODO:
         *
         * Preparing preset parameters for
         * embedded, ordinary PC, HPC, etc...
         * would be helpful.
         */
        for_each_bench(coll, bench) {
                if (!bench->fn)
                        break;
                printf("# Running %s/%s benchmark...\n", coll->name, bench->name);
                fflush(stdout);

                argv[1] = bench->name;
                run_bench(coll->name, bench->name, bench->fn, 1, argv, NULL);
                printf("\n");
        }
}

static void run_all_collections(void)
{
        struct collection *coll;

        for_each_collection(coll)
                run_collection(coll);
}

int cmd_bench(int argc, const char **argv, const char *prefix __maybe_unused)
{
        struct collection *coll;
        int ret = 0;

        if (argc < 2) {
                /* No collection specified. */
                print_usage();
                goto end;
        }

        argc = parse_options(argc, argv, bench_options, bench_usage,
                             PARSE_OPT_STOP_AT_NON_OPTION);

        bench_format = bench_str2int(bench_format_str);
        if (bench_format == BENCH_FORMAT_UNKNOWN) {
                printf("Unknown format descriptor: '%s'\n", bench_format_str);
                goto end;
        }

        if (bench_repeat == 0) {
                printf("Invalid repeat option: Must specify a positive value\n");
                goto end;
        }

        if (argc < 1) {
                print_usage();
                goto end;
        }

        if (!strcmp(argv[0], "all")) {
                run_all_collections();
                goto end;
        }

        for_each_collection(coll) {
                struct bench *bench;

                if (strcmp(coll->name, argv[0]))
                        continue;

                if (argc < 2) {
                        /* No bench specified. */
                        dump_benchmarks(coll);
                        goto end;
                }

                if (!strcmp(argv[1], "all")) {
                        run_collection(coll);
                        goto end;
                }

                for_each_bench(coll, bench) {
                        if (strcmp(bench->name, argv[1]))
                                continue;

                        if (bench_format == BENCH_FORMAT_DEFAULT)
                                printf("# Running '%s/%s' benchmark:\n", coll->name, bench->name);
                        fflush(stdout);
                        ret = run_bench(coll->name, bench->name, bench->fn, argc-1, argv+1, prefix);
                        goto end;
                }

                if (!strcmp(argv[1], "-h") || !strcmp(argv[1], "--help")) {
                        dump_benchmarks(coll);
                        goto end;
                }

                printf("Unknown benchmark: '%s' for collection '%s'\n", argv[1], argv[0]);
                ret = 1;
                goto end;
        }

        printf("Unknown collection: '%s'\n", argv[0]);
        ret = 1;

end:
        return ret;
}