diff options
Diffstat (limited to 'drivers/gator/gator_events_block.c')
| -rw-r--r-- | drivers/gator/gator_events_block.c | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/drivers/gator/gator_events_block.c b/drivers/gator/gator_events_block.c new file mode 100644 index 00000000000..56c6a673652 --- /dev/null +++ b/drivers/gator/gator_events_block.c @@ -0,0 +1,155 @@ +/** + * 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. + * + */ + +#include "gator.h" +#include <trace/events/block.h> + +#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]; + +GATOR_DEFINE_PROBE(block_rq_complete, TP_PROTO(struct request_queue *q, struct request *rq)) +{ + int write, size; + + if (!rq) + return; + + write = rq->cmd_flags & EVENTWRITE; + size = rq->resid_len; + + 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) +{ + 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; + blockGet[len++] = 0; // indicates to Streamline that value bytes were written now, not since the last message + 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; + blockGet[len++] = 0; // indicates to Streamline that value bytes were read now, not since the last message + 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); +} + +gator_events_init(gator_events_block_init); |