RE: [PATCH 3/7] scsi: fnic: no need to check return value of debugfs_create functions

["Satish Kharat (satishkh)" <satishkh@cisco.com>]

Looks good to me.
Acked-by: Satish Kharat <satishkh@cisco.com>


Satish Kharat
TECHNICAL LEADER.ENGINEERING
satishkh@cisco.com

-----Original Message-----
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Sent: Tuesday, January 22, 2019 7:09 AM
To: James Bottomley <jejb@linux.ibm.com>; Martin Petersen <martin.petersen@oracle.com>
Cc: linux-kernel@vger.kernel.org; linux-scsi@vger.kernel.org; Greg Kroah-Hartman <gregkh@linuxfoundation.org>; Satish Kharat (satishkh) <satishkh@cisco.com>; Sesidhar Baddela (sebaddel) <sebaddel@cisco.com>; Karan Tilak Kumar (kartilak) <kartilak@cisco.com>
Subject: [PATCH 3/7] scsi: fnic: no need to check return value of debugfs_create functions

When calling debugfs functions, there is no need to ever check the return value.  The function can work or not, but the code logic should never do something different based on this.

Cc: Satish Kharat <satishkh@cisco.com>
Cc: Sesidhar Baddela <sebaddel@cisco.com>
Cc: Karan Tilak Kumar <kartilak@cisco.com>
Cc: "James E.J. Bottomley" <jejb@linux.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: linux-scsi@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/scsi/fnic/fnic_debugfs.c | 88 ++------------------------------
 drivers/scsi/fnic/fnic_main.c    |  7 +--
 drivers/scsi/fnic/fnic_stats.h   |  2 +-
 drivers/scsi/fnic/fnic_trace.c   | 17 ++----
 drivers/scsi/fnic/fnic_trace.h   |  4 +-
 5 files changed, 10 insertions(+), 108 deletions(-)

diff --git a/drivers/scsi/fnic/fnic_debugfs.c b/drivers/scsi/fnic/fnic_debugfs.c
index 139fffa3658a..21991c99db7c 100644
--- a/drivers/scsi/fnic/fnic_debugfs.c
+++ b/drivers/scsi/fnic/fnic_debugfs.c
@@ -54,23 +54,9 @@ int fnic_debugfs_init(void)  {
 	int rc = -1;
 	fnic_trace_debugfs_root = debugfs_create_dir("fnic", NULL);
-	if (!fnic_trace_debugfs_root) {
-		printk(KERN_DEBUG "Cannot create debugfs root\n");
-		return rc;
-	}
-
-	if (!fnic_trace_debugfs_root) {
-		printk(KERN_DEBUG
-			"fnic root directory doesn't exist in debugfs\n");
-		return rc;
-	}
 
 	fnic_stats_debugfs_root = debugfs_create_dir("statistics",
 						fnic_trace_debugfs_root);
-	if (!fnic_stats_debugfs_root) {
-		printk(KERN_DEBUG "Cannot create Statistics directory\n");
-		return rc;
-	}
 
 	/* Allocate memory to structure */
 	fc_trc_flag = (struct fc_trace_flag_type *) @@ -356,39 +342,19 @@ static const struct file_operations fnic_trace_debugfs_fops = {
  * it will also create file trace_enable to control enable/disable of
  * trace logging into trace buffer.
  */
-int fnic_trace_debugfs_init(void)
+void fnic_trace_debugfs_init(void)
 {
-	int rc = -1;
-	if (!fnic_trace_debugfs_root) {
-		printk(KERN_DEBUG
-			"FNIC Debugfs root directory doesn't exist\n");
-		return rc;
-	}
 	fnic_trace_enable = debugfs_create_file("tracing_enable",
 					S_IFREG|S_IRUGO|S_IWUSR,
 					fnic_trace_debugfs_root,
 					&(fc_trc_flag->fnic_trace),
 					&fnic_trace_ctrl_fops);
 
-	if (!fnic_trace_enable) {
-		printk(KERN_DEBUG
-			"Cannot create trace_enable file under debugfs\n");
-		return rc;
-	}
-
 	fnic_trace_debugfs_file = debugfs_create_file("trace",
 					S_IFREG|S_IRUGO|S_IWUSR,
 					fnic_trace_debugfs_root,
 					&(fc_trc_flag->fnic_trace),
 					&fnic_trace_debugfs_fops);
-
-	if (!fnic_trace_debugfs_file) {
-		printk(KERN_DEBUG
-			"Cannot create trace file under debugfs\n");
-		return rc;
-	}
-	rc = 0;
-	return rc;
 }
 
 /*
@@ -419,37 +385,20 @@ void fnic_trace_debugfs_terminate(void)
  * trace logging into trace buffer.
  */
 
-int fnic_fc_trace_debugfs_init(void)
+void fnic_fc_trace_debugfs_init(void)
 {
-	int rc = -1;
-
-	if (!fnic_trace_debugfs_root) {
-		pr_err("fnic:Debugfs root directory doesn't exist\n");
-		return rc;
-	}
-
 	fnic_fc_trace_enable = debugfs_create_file("fc_trace_enable",
 					S_IFREG|S_IRUGO|S_IWUSR,
 					fnic_trace_debugfs_root,
 					&(fc_trc_flag->fc_trace),
 					&fnic_trace_ctrl_fops);
 
-	if (!fnic_fc_trace_enable) {
-		pr_err("fnic: Failed create fc_trace_enable file\n");
-		return rc;
-	}
-
 	fnic_fc_trace_clear = debugfs_create_file("fc_trace_clear",
 					S_IFREG|S_IRUGO|S_IWUSR,
 					fnic_trace_debugfs_root,
 					&(fc_trc_flag->fc_clear),
 					&fnic_trace_ctrl_fops);
 
-	if (!fnic_fc_trace_clear) {
-		pr_err("fnic: Failed to create fc_trace_enable file\n");
-		return rc;
-	}
-
 	fnic_fc_rdata_trace_debugfs_file =
 		debugfs_create_file("fc_trace_rdata",
 				    S_IFREG|S_IRUGO|S_IWUSR,
@@ -457,24 +406,12 @@ int fnic_fc_trace_debugfs_init(void)
 				    &(fc_trc_flag->fc_normal_file),
 				    &fnic_trace_debugfs_fops);
 
-	if (!fnic_fc_rdata_trace_debugfs_file) {
-		pr_err("fnic: Failed create fc_rdata_trace file\n");
-		return rc;
-	}
-
 	fnic_fc_trace_debugfs_file =
 		debugfs_create_file("fc_trace",
 				    S_IFREG|S_IRUGO|S_IWUSR,
 				    fnic_trace_debugfs_root,
 				    &(fc_trc_flag->fc_row_file),
 				    &fnic_trace_debugfs_fops);
-
-	if (!fnic_fc_trace_debugfs_file) {
-		pr_err("fnic: Failed to create fc_trace file\n");
-		return rc;
-	}
-	rc = 0;
-	return rc;
 }
 
 /*
@@ -757,45 +694,26 @@ static const struct file_operations fnic_reset_debugfs_fops = {
  * It will create file stats and reset_stats under statistics/host# directory
  * to log per fnic stats.
  */
-int fnic_stats_debugfs_init(struct fnic *fnic)
+void fnic_stats_debugfs_init(struct fnic *fnic)
 {
-	int rc = -1;
 	char name[16];
 
 	snprintf(name, sizeof(name), "host%d", fnic->lport->host->host_no);
 
-	if (!fnic_stats_debugfs_root) {
-		printk(KERN_DEBUG "fnic_stats root doesn't exist\n");
-		return rc;
-	}
 	fnic->fnic_stats_debugfs_host = debugfs_create_dir(name,
 						fnic_stats_debugfs_root);
-	if (!fnic->fnic_stats_debugfs_host) {
-		printk(KERN_DEBUG "Cannot create host directory\n");
-		return rc;
-	}
 
 	fnic->fnic_stats_debugfs_file = debugfs_create_file("stats",
 						S_IFREG|S_IRUGO|S_IWUSR,
 						fnic->fnic_stats_debugfs_host,
 						fnic,
 						&fnic_stats_debugfs_fops);
-	if (!fnic->fnic_stats_debugfs_file) {
-		printk(KERN_DEBUG "Cannot create host stats file\n");
-		return rc;
-	}
 
 	fnic->fnic_reset_debugfs_file = debugfs_create_file("reset_stats",
 						S_IFREG|S_IRUGO|S_IWUSR,
 						fnic->fnic_stats_debugfs_host,
 						fnic,
 						&fnic_reset_debugfs_fops);
-	if (!fnic->fnic_reset_debugfs_file) {
-		printk(KERN_DEBUG "Cannot create host stats file\n");
-		return rc;
-	}
-	rc = 0;
-	return rc;
 }
 
 /*
diff --git a/drivers/scsi/fnic/fnic_main.c b/drivers/scsi/fnic/fnic_main.c index 5b3534b0deda..cc8f7c82e2ba 100644
--- a/drivers/scsi/fnic/fnic_main.c
+++ b/drivers/scsi/fnic/fnic_main.c
@@ -578,12 +578,7 @@ static int fnic_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 	host->transportt = fnic_fc_transport;
 
-	err = fnic_stats_debugfs_init(fnic);
-	if (err) {
-		shost_printk(KERN_ERR, fnic->lport->host,
-				"Failed to initialize debugfs for stats\n");
-		fnic_stats_debugfs_remove(fnic);
-	}
+	fnic_stats_debugfs_init(fnic);
 
 	/* Setup PCI resources */
 	pci_set_drvdata(pdev, fnic);
diff --git a/drivers/scsi/fnic/fnic_stats.h b/drivers/scsi/fnic/fnic_stats.h index 9daa6ada6fa0..09c3f864c1cf 100644
--- a/drivers/scsi/fnic/fnic_stats.h
+++ b/drivers/scsi/fnic/fnic_stats.h
@@ -134,6 +134,6 @@ struct stats_debug_info {  };
 
 int fnic_get_stats_data(struct stats_debug_info *, struct fnic_stats *); -int fnic_stats_debugfs_init(struct fnic *);
+void fnic_stats_debugfs_init(struct fnic *);
 void fnic_stats_debugfs_remove(struct fnic *);  #endif /* _FNIC_STATS_H_ */ diff --git a/drivers/scsi/fnic/fnic_trace.c b/drivers/scsi/fnic/fnic_trace.c index bf0fd2aeb92e..c08eda9ef086 100644
--- a/drivers/scsi/fnic/fnic_trace.c
+++ b/drivers/scsi/fnic/fnic_trace.c
@@ -503,15 +503,10 @@ int fnic_trace_buf_init(void)
 		fnic_trace_entries.page_offset[i] = fnic_buf_head;
 		fnic_buf_head += FNIC_ENTRY_SIZE_BYTES;
 	}
-	err = fnic_trace_debugfs_init();
-	if (err < 0) {
-		pr_err("fnic: Failed to initialize debugfs for tracing\n");
-		goto err_fnic_trace_debugfs_init;
-	}
+	fnic_trace_debugfs_init();
 	pr_info("fnic: Successfully Initialized Trace Buffer\n");
 	return err;
-err_fnic_trace_debugfs_init:
-	fnic_trace_free();
+
 err_fnic_trace_buf_init:
 	return err;
 }
@@ -596,16 +591,10 @@ int fnic_fc_trace_init(void)
 		fc_trace_entries.page_offset[i] = fc_trace_buf_head;
 		fc_trace_buf_head += FC_TRC_SIZE_BYTES;
 	}
-	err = fnic_fc_trace_debugfs_init();
-	if (err < 0) {
-		pr_err("fnic: Failed to initialize FC_CTLR tracing.\n");
-		goto err_fnic_fc_ctlr_trace_debugfs_init;
-	}
+	fnic_fc_trace_debugfs_init();
 	pr_info("fnic: Successfully Initialized FC_CTLR Trace Buffer\n");
 	return err;
 
-err_fnic_fc_ctlr_trace_debugfs_init:
-	fnic_fc_trace_free();
 err_fnic_fc_ctlr_trace_buf_init:
 	return err;
 }
diff --git a/drivers/scsi/fnic/fnic_trace.h b/drivers/scsi/fnic/fnic_trace.h index e375d0c2eaaf..8aa55c1e2025 100644
--- a/drivers/scsi/fnic/fnic_trace.h
+++ b/drivers/scsi/fnic/fnic_trace.h
@@ -111,7 +111,7 @@ int fnic_trace_buf_init(void);  void fnic_trace_free(void);  int fnic_debugfs_init(void);  void fnic_debugfs_terminate(void); -int fnic_trace_debugfs_init(void);
+void fnic_trace_debugfs_init(void);
 void fnic_trace_debugfs_terminate(void);
 
 /* Fnic FC CTLR Trace releated function */ @@ -123,7 +123,7 @@ int fnic_fc_trace_get_data(fnic_dbgfs_t *fnic_dbgfs_prt, u8 rdata_flag);  void copy_and_format_trace_data(struct fc_trace_hdr *tdata,
 				fnic_dbgfs_t *fnic_dbgfs_prt,
 				int *len, u8 rdata_flag);
-int fnic_fc_trace_debugfs_init(void);
+void fnic_fc_trace_debugfs_init(void);
 void fnic_fc_trace_debugfs_terminate(void);
 
 #endif
--
2.20.1