diff options
Diffstat (limited to 'tools/gator/daemon/Collector.cpp')
-rw-r--r-- | tools/gator/daemon/Collector.cpp | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/tools/gator/daemon/Collector.cpp b/tools/gator/daemon/Collector.cpp new file mode 100644 index 00000000000..bf73534692a --- /dev/null +++ b/tools/gator/daemon/Collector.cpp @@ -0,0 +1,221 @@ +/** + * Copyright (C) ARM Limited 2010-2013. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#define __STDC_FORMAT_MACROS + +#include <fcntl.h> +#include <unistd.h> +#include <string.h> +#include <stdlib.h> +#include <errno.h> +#include <sys/time.h> +#include <inttypes.h> +#include "Collector.h" +#include "SessionData.h" +#include "Logging.h" +#include "Sender.h" + +// Driver initialization independent of session settings +Collector::Collector() { + mBufferFD = 0; + + checkVersion(); + + int enable = -1; + if (readIntDriver("/dev/gator/enable", &enable) != 0 || enable != 0) { + logg->logError(__FILE__, __LINE__, "Driver already enabled, possibly a session is already in progress."); + handleException(); + } + + readIntDriver("/dev/gator/cpu_cores", &gSessionData->mCores); + if (gSessionData->mCores == 0) { + gSessionData->mCores = 1; + } + + mBufferSize = 0; + if (readIntDriver("/dev/gator/buffer_size", &mBufferSize) || mBufferSize <= 0) { + logg->logError(__FILE__, __LINE__, "Unable to read the driver buffer size"); + handleException(); + } +} + +Collector::~Collector() { + // Write zero for safety, as a zero should have already been written + writeDriver("/dev/gator/enable", "0"); + + // Calls event_buffer_release in the driver + if (mBufferFD) { + close(mBufferFD); + } +} + +void Collector::checkVersion() { + int driver_version = 0; + + if (readIntDriver("/dev/gator/version", &driver_version) == -1) { + logg->logError(__FILE__, __LINE__, "Error reading gator driver version"); + handleException(); + } + + // Verify the driver version matches the daemon version + if (driver_version != PROTOCOL_VERSION) { + if ((driver_version > PROTOCOL_DEV) || (PROTOCOL_VERSION > PROTOCOL_DEV)) { + // One of the mismatched versions is development version + logg->logError(__FILE__, __LINE__, + "DEVELOPMENT BUILD MISMATCH: gator driver version \"%d\" is not in sync with gator daemon version \"%d\".\n" + ">> The following must be synchronized from engineering repository:\n" + ">> * gator driver\n" + ">> * gator daemon\n" + ">> * Streamline", driver_version, PROTOCOL_VERSION); + handleException(); + } else { + // Release version mismatch + logg->logError(__FILE__, __LINE__, + "gator driver version \"%d\" is different than gator daemon version \"%d\".\n" + ">> Please upgrade the driver and daemon to the latest versions.", driver_version, PROTOCOL_VERSION); + handleException(); + } + } +} + +void Collector::start() { + // Set the maximum backtrace depth + if (writeReadDriver("/dev/gator/backtrace_depth", &gSessionData->mBacktraceDepth)) { + logg->logError(__FILE__, __LINE__, "Unable to set the driver backtrace depth"); + handleException(); + } + + // open the buffer which calls userspace_buffer_open() in the driver + mBufferFD = open("/dev/gator/buffer", O_RDONLY); + if (mBufferFD < 0) { + logg->logError(__FILE__, __LINE__, "The gator driver did not set up properly. Please view the linux console or dmesg log for more information on the failure."); + handleException(); + } + + // set the tick rate of the profiling timer + if (writeReadDriver("/dev/gator/tick", &gSessionData->mSampleRate) != 0) { + logg->logError(__FILE__, __LINE__, "Unable to set the driver tick"); + handleException(); + } + + // notify the kernel of the response type + int response_type = gSessionData->mLocalCapture ? 0 : RESPONSE_APC_DATA; + if (writeDriver("/dev/gator/response_type", response_type)) { + logg->logError(__FILE__, __LINE__, "Unable to write the response type"); + handleException(); + } + + // Set the live rate + if (writeReadDriver("/dev/gator/live_rate", &gSessionData->mLiveRate)) { + logg->logError(__FILE__, __LINE__, "Unable to set the driver live rate"); + handleException(); + } + + logg->logMessage("Start the driver"); + + // This command makes the driver start profiling by calling gator_op_start() in the driver + if (writeDriver("/dev/gator/enable", "1") != 0) { + logg->logError(__FILE__, __LINE__, "The gator driver did not start properly. Please view the linux console or dmesg log for more information on the failure."); + handleException(); + } + + lseek(mBufferFD, 0, SEEK_SET); +} + +// These commands should cause the read() function in collect() to return +void Collector::stop() { + // This will stop the driver from profiling + if (writeDriver("/dev/gator/enable", "0") != 0) { + logg->logMessage("Stopping kernel failed"); + } +} + +int Collector::collect(char* buffer) { + // Calls event_buffer_read in the driver + int bytesRead; + + errno = 0; + bytesRead = read(mBufferFD, buffer, mBufferSize); + + // If read() returned due to an interrupt signal, re-read to obtain the last bit of collected data + if (bytesRead == -1 && errno == EINTR) { + bytesRead = read(mBufferFD, buffer, mBufferSize); + } + + // return the total bytes written + logg->logMessage("Driver read of %d bytes", bytesRead); + return bytesRead; +} + +int Collector::readIntDriver(const char* fullpath, int* value) { + FILE* file = fopen(fullpath, "r"); + if (file == NULL) { + return -1; + } + if (fscanf(file, "%u", value) != 1) { + fclose(file); + logg->logMessage("Invalid value in file %s", fullpath); + return -1; + } + fclose(file); + return 0; +} + +int Collector::readInt64Driver(const char* fullpath, int64_t* value) { + FILE* file = fopen(fullpath, "r"); + if (file == NULL) { + return -1; + } + if (fscanf(file, "%" SCNi64, value) != 1) { + fclose(file); + logg->logMessage("Invalid value in file %s", fullpath); + return -1; + } + fclose(file); + return 0; +} + +int Collector::writeDriver(const char* path, int value) { + char data[40]; // Sufficiently large to hold any integer + snprintf(data, sizeof(data), "%d", value); + return writeDriver(path, data); +} + +int Collector::writeDriver(const char* path, int64_t value) { + char data[40]; // Sufficiently large to hold any integer + snprintf(data, sizeof(data), "%" PRIi64, value); + return writeDriver(path, data); +} + +int Collector::writeDriver(const char* fullpath, const char* data) { + int fd = open(fullpath, O_WRONLY); + if (fd < 0) { + return -1; + } + if (write(fd, data, strlen(data)) < 0) { + close(fd); + logg->logMessage("Opened but could not write to %s", fullpath); + return -1; + } + close(fd); + return 0; +} + +int Collector::writeReadDriver(const char* path, int* value) { + if (writeDriver(path, *value) || readIntDriver(path, value)) { + return -1; + } + return 0; +} + +int Collector::writeReadDriver(const char* path, int64_t* value) { + if (writeDriver(path, *value) || readInt64Driver(path, value)) { + return -1; + } + return 0; +} |