1 files changed, 139 insertions, 0 deletions
diff --git a/tools/gator/daemon/PerfBuffer.cpp b/tools/gator/daemon/PerfBuffer.cpp
new file mode 100644
index 000000000000..5fad583f7bd0
--- /dev/null
+++ b/tools/gator/daemon/PerfBuffer.cpp
@@ -0,0 +1,139 @@
+/**
+ * Copyright (C) ARM Limited 2013-2014. 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.
+ */
+
+#include "PerfBuffer.h"
+
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+
+#include "Buffer.h"
+#include "Logging.h"
+#include "Sender.h"
+#include "SessionData.h"
+
+PerfBuffer::PerfBuffer() {
+	for (int cpu = 0; cpu < ARRAY_LENGTH(mBuf); ++cpu) {
+		mBuf[cpu] = MAP_FAILED;
+		mDiscard[cpu] = false;
+	}
+}
+
+PerfBuffer::~PerfBuffer() {
+	for (int cpu = ARRAY_LENGTH(mBuf) - 1; cpu >= 0; --cpu) {
+		if (mBuf[cpu] != MAP_FAILED) {
+			munmap(mBuf[cpu], gSessionData->mPageSize + BUF_SIZE);
+		}
+	}
+}
+
+bool PerfBuffer::useFd(const int cpu, const int fd, const int groupFd) {
+	if (fd == groupFd) {
+		if (mBuf[cpu] != MAP_FAILED) {
+			logg->logMessage("%s(%s:%i): cpu %i already online or not correctly cleaned up", __FUNCTION__, __FILE__, __LINE__, cpu);
+			return false;
+		}
+
+		// The buffer isn't mapped yet
+		mBuf[cpu] = mmap(NULL, gSessionData->mPageSize + BUF_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
+		if (mBuf[cpu] == MAP_FAILED) {
+			logg->logMessage("%s(%s:%i): mmap failed", __FUNCTION__, __FILE__, __LINE__);
+			return false;
+		}
+
+		// Check the version
+		struct perf_event_mmap_page *pemp = static_cast<struct perf_event_mmap_page *>(mBuf[cpu]);
+		if (pemp->compat_version != 0) {
+			logg->logMessage("%s(%s:%i): Incompatible perf_event_mmap_page compat_version", __FUNCTION__, __FILE__, __LINE__);
+			return false;
+		}
+	} else {
+		if (mBuf[cpu] == MAP_FAILED) {
+			logg->logMessage("%s(%s:%i): cpu already online or not correctly cleaned up", __FUNCTION__, __FILE__, __LINE__);
+			return false;
+		}
+
+		if (ioctl(fd, PERF_EVENT_IOC_SET_OUTPUT, groupFd) < 0) {
+			logg->logMessage("%s(%s:%i): ioctl failed", __FUNCTION__, __FILE__, __LINE__);
+			return false;
+		}
+	}
+
+	return true;
+}
+
+void PerfBuffer::discard(const int cpu) {
+	if (mBuf[cpu] != MAP_FAILED) {
+		mDiscard[cpu] = true;
+	}
+}
+
+bool PerfBuffer::isEmpty() {
+	for (int cpu = 0; cpu < gSessionData->mCores; ++cpu) {
+		if (mBuf[cpu] != MAP_FAILED) {
+			// Take a snapshot of the positions
+			struct perf_event_mmap_page *pemp = static_cast<struct perf_event_mmap_page *>(mBuf[cpu]);
+			const __u64 head = pemp->data_head;
+			const __u64 tail = pemp->data_tail;
+
+			if (head != tail) {
+				return false;
+			}
+		}
+	}
+
+	return true;
+}
+
+bool PerfBuffer::send(Sender *const sender) {
+	for (int cpu = 0; cpu < gSessionData->mCores; ++cpu) {
+		if (mBuf[cpu] == MAP_FAILED) {
+			continue;
+		}
+
+		// Take a snapshot of the positions
+		struct perf_event_mmap_page *pemp = static_cast<struct perf_event_mmap_page *>(mBuf[cpu]);
+		const __u64 head = pemp->data_head;
+		const __u64 tail = pemp->data_tail;
+
+		if (head > tail) {
+			const uint8_t *const b = static_cast<uint8_t *>(mBuf[cpu]) + gSessionData->mPageSize;
+			const int offset = gSessionData->mLocalCapture ? 1 : 0;
+			unsigned char header[7];
+			header[0] = RESPONSE_APC_DATA;
+			Buffer::writeLEInt(header + 1, head - tail + sizeof(header) - 5);
+			// Should use real packing functions
+			header[5] = FRAME_PERF;
+			header[6] = cpu;
+
+			// Write header
+			sender->writeData(reinterpret_cast<const char *>(&header) + offset, sizeof(header) - offset, RESPONSE_APC_DATA);
+
+			// Write data
+			if ((head & ~BUF_MASK) == (tail & ~BUF_MASK)) {
+				// Not wrapped
+				sender->writeData(reinterpret_cast<const char *>(b + (tail & BUF_MASK)), head - tail, RESPONSE_APC_DATA);
+			} else {
+				// Wrapped
+				sender->writeData(reinterpret_cast<const char *>(b + (tail & BUF_MASK)), BUF_SIZE - (tail & BUF_MASK), RESPONSE_APC_DATA);
+				sender->writeData(reinterpret_cast<const char *>(b), head & BUF_MASK, RESPONSE_APC_DATA);
+			}
+
+			// Update tail with the data read
+			pemp->data_tail = head;
+		}
+
+		if (mDiscard[cpu]) {
+			munmap(mBuf[cpu], gSessionData->mPageSize + BUF_SIZE);
+			mBuf[cpu] = MAP_FAILED;
+			mDiscard[cpu] = false;
+			logg->logMessage("%s(%s:%i): Unmaped cpu %i", __FUNCTION__, __FILE__, __LINE__, cpu);
+		}
+	}
+
+	return true;
+}