fnic: fnic Control Path Trace Utility

Fnic Ctlr Path Trace utility is a tracing functionality built directly into fnic
driver to trace the control path frames like discovery, FLOGI request/reply,
PLOGI request/reply, link event etc.  It will be one trace file for all fnics.
It will help us to debug and resolve the discovery and initialization related
issues in more convenient way. This trace information includes time stamp,
Host Number, Frame type, Frame Length and Frame. By default,64 pages are
allocated but we can change the number of allocated pages by module parameter
fnic_fc_trace_max_page. Each entry is of 256 byte and available entries are
depends on allocated number of pages. We can turn on or off the fnic control
path trace functionality by module paramter fc_trace_enable and/or reset the
trace contain by module paramter fc_trace_clear.

Signed-off-by: Hiral Shah <hishah@cisco.com>
Signed-off-by: Sesidhar Baddela <sebaddel@cisco.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

1 files changed, 18 insertions, 2 deletions

diff --git a/drivers/scsi/fnic/fnic_main.c b/drivers/scsi/fnic/fnic_main.c
index 05657da583a2..8c56fdc3a456 100644
--- a/drivers/scsi/fnic/fnic_main.c
+++ b/drivers/scsi/fnic/fnic_main.c
@@ -74,6 +74,11 @@ module_param(fnic_trace_max_pages, uint, S_IRUGO|S_IWUSR);
 MODULE_PARM_DESC(fnic_trace_max_pages, "Total allocated memory pages "
 					"for fnic trace buffer");
 
+unsigned int fnic_fc_trace_max_pages = 64;
+module_param(fnic_fc_trace_max_pages, uint, S_IRUGO|S_IWUSR);
+MODULE_PARM_DESC(fnic_fc_trace_max_pages,
+		 "Total allocated memory pages for fc trace buffer");
+
 static unsigned int fnic_max_qdepth = FNIC_DFLT_QUEUE_DEPTH;
 module_param(fnic_max_qdepth, uint, S_IRUGO|S_IWUSR);
 MODULE_PARM_DESC(fnic_max_qdepth, "Queue depth to report for each LUN");
@@ -1034,11 +1039,20 @@ static int __init fnic_init_module(void)
 	/* Allocate memory for trace buffer */
 	err = fnic_trace_buf_init();
 	if (err < 0) {
-		printk(KERN_ERR PFX "Trace buffer initialization Failed "
-				  "Fnic Tracing utility is disabled\n");
+		printk(KERN_ERR PFX
+		       "Trace buffer initialization Failed. "
+		       "Fnic Tracing utility is disabled\n");
 		fnic_trace_free();
 	}
 
+    /* Allocate memory for fc trace buffer */
+	err = fnic_fc_trace_init();
+	if (err < 0) {
+		printk(KERN_ERR PFX "FC trace buffer initialization Failed "
+		       "FC frame tracing utility is disabled\n");
+		fnic_fc_trace_free();
+	}
+
 	/* Create a cache for allocation of default size sgls */
 	len = sizeof(struct fnic_dflt_sgl_list);
 	fnic_sgl_cache[FNIC_SGL_CACHE_DFLT] = kmem_cache_create
@@ -1119,6 +1133,7 @@ err_create_fnic_sgl_slab_max:
 	kmem_cache_destroy(fnic_sgl_cache[FNIC_SGL_CACHE_DFLT]);
 err_create_fnic_sgl_slab_dflt:
 	fnic_trace_free();
+	fnic_fc_trace_free();
 	fnic_debugfs_terminate();
 	return err;
 }
@@ -1136,6 +1151,7 @@ static void __exit fnic_cleanup_module(void)
 	kmem_cache_destroy(fnic_io_req_cache);
 	fc_release_transport(fnic_fc_transport);
 	fnic_trace_free();
+	fnic_fc_trace_free();
 	fnic_debugfs_terminate();
 }