vperfetto_merge.cpp

#include "vperfetto.h"

#include <filesystem>
#include <fstream>
#include <sstream>

#include <string.h>
#include <stdlib.h>

static bool sValidFilename(const char* fn) {
    if (!fn) {
        fprintf(stderr, "ERROR: Invalid filename (is null)\n");
        return false;
    }

    if (!strcmp("", fn)) {
        fprintf(stderr, "ERROR: Invalid filename (is empty string)\n");
        return false;
    }

    if (!std::filesystem::exists(fn)) {
        fprintf(stderr, "ERROR: Filename [%s] does not refer to a filesystem object. As absolute: [%s]\n", fn, std::filesystem::absolute(fn).c_str());
        return false;
    }

    if (!std::filesystem::is_regular_file(fn)) {
        fprintf(stderr, "ERROR: Filename [%s] does not refer to a regular file. As absolute: [%s]\n", fn, std::filesystem::absolute(fn).c_str());
        return false;
    }

    if (std::filesystem::is_empty(fn)) {
        fprintf(stderr, "ERROR: Filename [%s] refers to an empty file. As absolute: [%s]\n", fn, std::filesystem::absolute(fn).c_str());
        return false;
    }

    return true;
}

int main(int argc, char** argv) {
    vperfetto::TraceCombineConfig config;

    if (argc < 4) {
        fprintf(stderr, "%s: error: invalid usage of vperfetto_merge. Usage: vperfetto_merge <guestTraceFile> <hostTraceFile> <combinedTraceFile>"
            " [<guestClockBootTimeNsWhenHostTracingStarted>]"
            " [--guest-tsc-offset <guest tsc-offset, ie: host file /sys/kernel/debug/kvm/4678-27/vcpu0/tsc-offset>]"
            " [--merge-guest-into-host]\n", __func__);
        return 1;
    }

    const char* guestFile = argv[1];
    const char* hostFile = argv[2];
    const char* combinedFile = argv[3];
    fprintf(stderr, "vperfetto_merge start. Configuration:\n", __func__);
    fprintf(stderr, "guest trace file: %s\n", guestFile);
    fprintf(stderr, "host trace file: %s\n", hostFile);
    fprintf(stderr, "combined trace file: %s\n", combinedFile);

    if (!sValidFilename(guestFile)) return 1;
    if (!sValidFilename(hostFile)) return 1;

    config.guestFile = guestFile;
    config.hostFile = hostFile;
    config.combinedFile = combinedFile;

    config.useGuestAbsoluteTime = false;
    config.useGuestTimeDiff = false;
    config.guestTscOffset = 0;
    config.mergeGuestIntoHost = false;

    for (int i = 4; i < argc; ++i) {
        auto arg = std::string(argv[i]);
        if (arg == "--guest-tsc-offset") {
            if (++i >= argc) {
                fprintf(stderr, "ERROR: missing value after --guest-tsc-offset\n");
                return 1;
            }

            // User specified guest boottime
            int64_t guestTscOffset;
            std::istringstream ss(argv[i]);
            if (!(ss >> guestTscOffset)) {
                fprintf(stderr, "ERROR: Failed to parse guest-tsc-offset. Provided: [%s]\n", argv[i]);
                return 1;
            } else {
                fprintf(stderr, "using specified guest-tsc-offset: %lld\n", (long long)guestTscOffset);
                config.guestTscOffset = guestTscOffset;
            }
        } else if (arg == "--merge-guest-into-host") {
            config.mergeGuestIntoHost = true;
        } else {
            // User specified guest boottime
            uint64_t guestClockBootTimeNs;
            std::istringstream ss(arg);
            if (!(ss >> guestClockBootTimeNs)) {
                fprintf(stderr, "ERROR: Failed to parse guest clock boot time ns. Provided: [%s]\n", arg.c_str());
                return 1;
            } else {
                fprintf(stderr, "using specified guest time diff: %llu\n", (unsigned long long)guestClockBootTimeNs);
                config.guestClockBootTimeNs = guestClockBootTimeNs;
                config.useGuestAbsoluteTime = true;
            }
        }
    }

    if (!config.useGuestAbsoluteTime && !config.useGuestTimeDiff) {
        // Derived guest boottime
        fprintf(stderr, "Will derive guest clock boot time and time diff.\n");
    }

    vperfetto::combineTraces(&config);
    return 0;
}