/** * Copyright (C) ARM Limited 2010-2015. 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 "gator.h" #include #define BLOCK_RQ_WR 0 #define BLOCK_RQ_RD 1 #define BLOCK_TOTAL (BLOCK_RQ_RD+1) #if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 36) #define EVENTWRITE REQ_RW #else #define EVENTWRITE REQ_WRITE #endif static ulong block_rq_wr_enabled; static ulong block_rq_rd_enabled; static ulong block_rq_wr_key; static ulong block_rq_rd_key; static atomic_t blockCnt[BLOCK_TOTAL]; static int blockGet[BLOCK_TOTAL * 4]; /* Tracepoint changed in 3.15 backported to older kernels. The Makefile tries to autodetect the correct value, but if it fails change the #if below */ #if OLD_BLOCK_RQ_COMPLETE GATOR_DEFINE_PROBE(block_rq_complete, TP_PROTO(struct request_queue *q, struct request *rq)) #else GATOR_DEFINE_PROBE(block_rq_complete, TP_PROTO(struct request_queue *q, struct request *rq, unsigned int nr_bytes)) #endif { int write; unsigned int size; if (!rq) return; write = rq->cmd_flags & EVENTWRITE; #if OLD_BLOCK_RQ_COMPLETE size = rq->resid_len; #else size = nr_bytes; #endif if (!size) return; if (write) { if (block_rq_wr_enabled) atomic_add(size, &blockCnt[BLOCK_RQ_WR]); } else { if (block_rq_rd_enabled) atomic_add(size, &blockCnt[BLOCK_RQ_RD]); } } static int gator_events_block_create_files(struct super_block *sb, struct dentry *root) { struct dentry *dir; /* block_complete_wr */ dir = gatorfs_mkdir(sb, root, "Linux_block_rq_wr"); if (!dir) return -1; gatorfs_create_ulong(sb, dir, "enabled", &block_rq_wr_enabled); gatorfs_create_ro_ulong(sb, dir, "key", &block_rq_wr_key); /* block_complete_rd */ dir = gatorfs_mkdir(sb, root, "Linux_block_rq_rd"); if (!dir) return -1; gatorfs_create_ulong(sb, dir, "enabled", &block_rq_rd_enabled); gatorfs_create_ro_ulong(sb, dir, "key", &block_rq_rd_key); return 0; } static int gator_events_block_start(void) { /* register tracepoints */ if (block_rq_wr_enabled || block_rq_rd_enabled) if (GATOR_REGISTER_TRACE(block_rq_complete)) goto fail_block_rq_exit; pr_debug("gator: registered block event tracepoints\n"); return 0; /* unregister tracepoints on error */ fail_block_rq_exit: pr_err("gator: block event tracepoints failed to activate, please verify that tracepoints are enabled in the linux kernel\n"); return -1; } static void gator_events_block_stop(void) { if (block_rq_wr_enabled || block_rq_rd_enabled) GATOR_UNREGISTER_TRACE(block_rq_complete); pr_debug("gator: unregistered block event tracepoints\n"); block_rq_wr_enabled = 0; block_rq_rd_enabled = 0; } static int gator_events_block_read(int **buffer, bool sched_switch) { int len, value, data = 0; if (!on_primary_core()) return 0; len = 0; if (block_rq_wr_enabled && (value = atomic_read(&blockCnt[BLOCK_RQ_WR])) > 0) { atomic_sub(value, &blockCnt[BLOCK_RQ_WR]); blockGet[len++] = block_rq_wr_key; /* Indicates to Streamline that value bytes were written now, not since the last message */ blockGet[len++] = 0; blockGet[len++] = block_rq_wr_key; blockGet[len++] = value; data += value; } if (block_rq_rd_enabled && (value = atomic_read(&blockCnt[BLOCK_RQ_RD])) > 0) { atomic_sub(value, &blockCnt[BLOCK_RQ_RD]); blockGet[len++] = block_rq_rd_key; /* Indicates to Streamline that value bytes were read now, not since the last message */ blockGet[len++] = 0; blockGet[len++] = block_rq_rd_key; blockGet[len++] = value; data += value; } if (buffer) *buffer = blockGet; return len; } static struct gator_interface gator_events_block_interface = { .create_files = gator_events_block_create_files, .start = gator_events_block_start, .stop = gator_events_block_stop, .read = gator_events_block_read, }; int gator_events_block_init(void) { block_rq_wr_enabled = 0; block_rq_rd_enabled = 0; block_rq_wr_key = gator_events_get_key(); block_rq_rd_key = gator_events_get_key(); return gator_events_install(&gator_events_block_interface); }