diff options
Diffstat (limited to 'drivers/scsi/snic/snic_trc.c')
| -rw-r--r-- | drivers/scsi/snic/snic_trc.c | 181 |
1 files changed, 181 insertions, 0 deletions
diff --git a/drivers/scsi/snic/snic_trc.c b/drivers/scsi/snic/snic_trc.c new file mode 100644 index 000000000000..28a40a7ade38 --- /dev/null +++ b/drivers/scsi/snic/snic_trc.c @@ -0,0 +1,181 @@ +/* + * Copyright 2014 Cisco Systems, Inc. All rights reserved. + * + * This program is free software; you may redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include <linux/module.h> +#include <linux/mempool.h> +#include <linux/errno.h> +#include <linux/vmalloc.h> + +#include "snic_io.h" +#include "snic.h" + +/* + * snic_get_trc_buf : Allocates a trace record and returns. + */ +struct snic_trc_data * +snic_get_trc_buf(void) +{ + struct snic_trc *trc = &snic_glob->trc; + struct snic_trc_data *td = NULL; + unsigned long flags; + + spin_lock_irqsave(&trc->lock, flags); + td = &trc->buf[trc->wr_idx]; + trc->wr_idx++; + + if (trc->wr_idx == trc->max_idx) + trc->wr_idx = 0; + + if (trc->wr_idx != trc->rd_idx) { + spin_unlock_irqrestore(&trc->lock, flags); + + goto end; + } + + trc->rd_idx++; + if (trc->rd_idx == trc->max_idx) + trc->rd_idx = 0; + + td->ts = 0; /* Marker for checking the record, for complete data*/ + spin_unlock_irqrestore(&trc->lock, flags); + +end: + + return td; +} /* end of snic_get_trc_buf */ + +/* + * snic_fmt_trc_data : Formats trace data for printing. + */ +static int +snic_fmt_trc_data(struct snic_trc_data *td, char *buf, int buf_sz) +{ + int len = 0; + struct timespec tmspec; + + jiffies_to_timespec(td->ts, &tmspec); + + len += snprintf(buf, buf_sz, + "%lu.%10lu %-25s %3d %4x %16llx %16llx %16llx %16llx %16llx\n", + tmspec.tv_sec, + tmspec.tv_nsec, + td->fn, + td->hno, + td->tag, + td->data[0], td->data[1], td->data[2], td->data[3], + td->data[4]); + + return len; +} /* end of snic_fmt_trc_data */ + +/* + * snic_get_trc_data : Returns a formatted trace buffer. + */ +int +snic_get_trc_data(char *buf, int buf_sz) +{ + struct snic_trc_data *td = NULL; + struct snic_trc *trc = &snic_glob->trc; + unsigned long flags; + + spin_lock_irqsave(&trc->lock, flags); + if (trc->rd_idx == trc->wr_idx) { + spin_unlock_irqrestore(&trc->lock, flags); + + return -1; + } + td = &trc->buf[trc->rd_idx]; + + if (td->ts == 0) { + /* write in progress. */ + spin_unlock_irqrestore(&trc->lock, flags); + + return -1; + } + + trc->rd_idx++; + if (trc->rd_idx == trc->max_idx) + trc->rd_idx = 0; + spin_unlock_irqrestore(&trc->lock, flags); + + return snic_fmt_trc_data(td, buf, buf_sz); +} /* end of snic_get_trc_data */ + +/* + * snic_trc_init() : Configures Trace Functionality for snic. + */ +int +snic_trc_init(void) +{ + struct snic_trc *trc = &snic_glob->trc; + void *tbuf = NULL; + int tbuf_sz = 0, ret; + + tbuf_sz = (snic_trace_max_pages * PAGE_SIZE); + tbuf = vmalloc(tbuf_sz); + if (!tbuf) { + SNIC_ERR("Failed to Allocate Trace Buffer Size. %d\n", tbuf_sz); + SNIC_ERR("Trace Facility not enabled.\n"); + ret = -ENOMEM; + + return ret; + } + + memset(tbuf, 0, tbuf_sz); + trc->buf = (struct snic_trc_data *) tbuf; + spin_lock_init(&trc->lock); + + ret = snic_trc_debugfs_init(); + if (ret) { + SNIC_ERR("Failed to create Debugfs Files.\n"); + + goto error; + } + + trc->max_idx = (tbuf_sz / SNIC_TRC_ENTRY_SZ); + trc->rd_idx = trc->wr_idx = 0; + trc->enable = 1; + SNIC_INFO("Trace Facility Enabled.\n Trace Buffer SZ %lu Pages.\n", + tbuf_sz / PAGE_SIZE); + ret = 0; + + return ret; + +error: + snic_trc_free(); + + return ret; +} /* end of snic_trc_init */ + +/* + * snic_trc_free : Releases the trace buffer and disables the tracing. + */ +void +snic_trc_free(void) +{ + struct snic_trc *trc = &snic_glob->trc; + + trc->enable = 0; + snic_trc_debugfs_term(); + + if (trc->buf) { + vfree(trc->buf); + trc->buf = NULL; + } + + SNIC_INFO("Trace Facility Disabled.\n"); +} /* end of snic_trc_free */ |