[21/37] lustre: remove several MAX_STRING_SIZE defines.
diff mbox series

Message ID 155053494593.24125.427229089746560574.stgit@noble.brown
State New
Headers show
Series
  • More lustre patches from obdclass
Related show

Commit Message

NeilBrown Feb. 19, 2019, 12:09 a.m. UTC
Some of these are unused.
One is used in a minimal way where it is easier to use
an explicit number.

Signed-off-by: NeilBrown <neilb@suse.com>
---
 drivers/staging/lustre/lustre/ldlm/ldlm_resource.c |    2 --
 drivers/staging/lustre/lustre/llite/llite_lib.c    |    6 ++----
 drivers/staging/lustre/lustre/llite/lproc_llite.c  |    4 ----
 drivers/staging/lustre/lustre/lmv/lmv_obd.c        |    2 --
 .../lustre/lustre/obdclass/lprocfs_status.c        |    2 --
 5 files changed, 2 insertions(+), 14 deletions(-)

Comments

James Simmons Feb. 24, 2019, 7:07 p.m. UTC | #1
> Some of these are unused.
> One is used in a minimal way where it is easier to use
> an explicit number.

While I dislike mystery meat type defines like MAX_STRING_SIZE I also 
don't like using raw numbers. In the past using raw numbers has causes
problems when requirements changed that were not easy to track down
why the new bug appeared. Mind you the same problem exist for constants 
like MAX_STRING_SIZE which provides no real meaning to why the magically 
number 128 is used. 
 
This number seems to be a limiting factor in the naming of sysfs directory
and file naming. I kind of see why this number has no meaning. So such
a number belongs in one place, lprocfs_status.h. Now sysfs attributes
can have any naming style they want, within reason :-) As for directories
that is limited by MAX_OBD_NAME. What do you know MAX_OBD_NAME is equal
too MAX_STRING_SIZE (hint hint) :-) 

> Signed-off-by: NeilBrown <neilb@suse.com>
> ---
>  drivers/staging/lustre/lustre/ldlm/ldlm_resource.c |    2 --
>  drivers/staging/lustre/lustre/llite/llite_lib.c    |    6 ++----
>  drivers/staging/lustre/lustre/llite/lproc_llite.c  |    4 ----
>  drivers/staging/lustre/lustre/lmv/lmv_obd.c        |    2 --
>  .../lustre/lustre/obdclass/lprocfs_status.c        |    2 --
>  5 files changed, 2 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/staging/lustre/lustre/ldlm/ldlm_resource.c b/drivers/staging/lustre/lustre/ldlm/ldlm_resource.c
> index 74c7644d6ef8..261857e4540d 100644
> --- a/drivers/staging/lustre/lustre/ldlm/ldlm_resource.c
> +++ b/drivers/staging/lustre/lustre/ldlm/ldlm_resource.c
> @@ -392,8 +392,6 @@ static int ldlm_namespace_debugfs_register(struct ldlm_namespace *ns)
>  	return 0;
>  }
>  
> -#undef MAX_STRING_SIZE
> -
>  struct ldlm_resource *ldlm_resource_getref(struct ldlm_resource *res)
>  {
>  	LASSERT(res);
> diff --git a/drivers/staging/lustre/lustre/llite/llite_lib.c b/drivers/staging/lustre/lustre/llite/llite_lib.c
> index d97abbfddccf..fda6d9b07952 100644
> --- a/drivers/staging/lustre/lustre/llite/llite_lib.c
> +++ b/drivers/staging/lustre/lustre/llite/llite_lib.c
> @@ -906,8 +906,6 @@ void ll_lli_init(struct ll_inode_info *lli)
>  	memset(lli->lli_jobid, 0, LUSTRE_JOBID_SIZE);
>  }
>  
> -#define MAX_STRING_SIZE 128
> -
>  int ll_fill_super(struct super_block *sb)
>  {
>  	struct lustre_profile *lprof = NULL;
> @@ -916,7 +914,7 @@ int ll_fill_super(struct super_block *sb)
>  	char *dt = NULL, *md = NULL;
>  	char *profilenm = get_profile_name(sb);
>  	struct config_llog_instance *cfg;
> -	char name[MAX_STRING_SIZE];
> +	char name[128];
>  	char *ptr;
>  	int len;
>  	int err;
> @@ -960,7 +958,7 @@ int ll_fill_super(struct super_block *sb)
>  		len -= 7;
>  
>  	/* Mount info */
> -	snprintf(name, MAX_STRING_SIZE, "%.*s-%px", len,
> +	snprintf(name, sizeof(name), "%.*s-%px", len,
>  		 lsi->lsi_lmd->lmd_profile, sb);
>  
>  	/* Call ll_debugsfs_register_super() before lustre_process_log()
> diff --git a/drivers/staging/lustre/lustre/llite/lproc_llite.c b/drivers/staging/lustre/lustre/llite/lproc_llite.c
> index db2fbf1f3a50..5ed703d7bb1e 100644
> --- a/drivers/staging/lustre/lustre/llite/lproc_llite.c
> +++ b/drivers/staging/lustre/lustre/llite/lproc_llite.c
> @@ -1187,8 +1187,6 @@ static struct lprocfs_vars lprocfs_llite_obd_vars[] = {
>  	{ NULL }
>  };
>  
> -#define MAX_STRING_SIZE 128
> -
>  static struct attribute *llite_attrs[] = {
>  	&lustre_attr_blocksize.attr,
>  	&lustre_attr_stat_blocksize.attr,
> @@ -1434,8 +1432,6 @@ void ll_debugfs_unregister_super(struct super_block *sb)
>  	lprocfs_free_stats(&sbi->ll_stats);
>  }
>  
> -#undef MAX_STRING_SIZE
> -
>  #define pct(a, b) (b ? a * 100 / b : 0)
>  
>  static void ll_display_extents_info(struct ll_rw_extents_info *io_extents,
> diff --git a/drivers/staging/lustre/lustre/lmv/lmv_obd.c b/drivers/staging/lustre/lustre/lmv/lmv_obd.c
> index 35dff0e96bf7..138e124bd05e 100644
> --- a/drivers/staging/lustre/lustre/lmv/lmv_obd.c
> +++ b/drivers/staging/lustre/lustre/lmv/lmv_obd.c
> @@ -273,8 +273,6 @@ static int lmv_init_ea_size(struct obd_export *exp, u32 easize, u32 def_easize)
>  	return rc;
>  }
>  
> -#define MAX_STRING_SIZE 128
> -
>  static int lmv_connect_mdc(struct obd_device *obd, struct lmv_tgt_desc *tgt)
>  {
>  	struct lmv_obd *lmv = &obd->u.lmv;
> diff --git a/drivers/staging/lustre/lustre/obdclass/lprocfs_status.c b/drivers/staging/lustre/lustre/obdclass/lprocfs_status.c
> index aed33068ff3c..a179b0d6979e 100644
> --- a/drivers/staging/lustre/lustre/obdclass/lprocfs_status.c
> +++ b/drivers/staging/lustre/lustre/obdclass/lprocfs_status.c
> @@ -271,8 +271,6 @@ static int lprocfs_no_percpu_stats;
>  module_param(lprocfs_no_percpu_stats, int, 0644);
>  MODULE_PARM_DESC(lprocfs_no_percpu_stats, "Do not alloc percpu data for lprocfs stats");
>  
> -#define MAX_STRING_SIZE 128
> -
>  /* lprocfs API calls */
>  
>  static const struct file_operations lprocfs_generic_fops = { };
> 
> 
>
Andreas Dilger Feb. 25, 2019, 6:16 p.m. UTC | #2
On Feb 18, 2019, at 16:09, NeilBrown <neilb@suse.com> wrote:
> 
> Some of these are unused.
> One is used in a minimal way where it is easier to use
> an explicit number.
> 
> Signed-off-by: NeilBrown <neilb@suse.com>

Reviewed-by: Andreas Dilger <adilger@whamcloud.com>


Cheers, Andreas
---
Andreas Dilger
Principal Lustre Architect
Whamcloud
NeilBrown Feb. 27, 2019, 12:41 a.m. UTC | #3
On Sun, Feb 24 2019, James Simmons wrote:

>> Some of these are unused.
>> One is used in a minimal way where it is easier to use
>> an explicit number.
>
> While I dislike mystery meat type defines like MAX_STRING_SIZE I also 
> don't like using raw numbers. In the past using raw numbers has causes
> problems when requirements changed that were not easy to track down
> why the new bug appeared. Mind you the same problem exist for constants 
> like MAX_STRING_SIZE which provides no real meaning to why the magically 
> number 128 is used. 
>  
> This number seems to be a limiting factor in the naming of sysfs directory
> and file naming. I kind of see why this number has no meaning. So such
> a number belongs in one place, lprocfs_status.h. Now sysfs attributes
> can have any naming style they want, within reason :-) As for directories
> that is limited by MAX_OBD_NAME. What do you know MAX_OBD_NAME is equal
> too MAX_STRING_SIZE (hint hint) :-) 

I've changed the 128 to MAX_OBD_NAME - seems to make sense.

I've also added the patch below.

Thanks,
NeilBrown

From: NeilBrown <neilb@suse.com>
Subject: [PATCH] lustre: ldlm: discard varname in ldlm_pool.

This allocated buffer serves no purpose.
A constant string is copied into it, it is passed to some
function which copies it out again, then the buffer is freed.
Instead, we can pass the constant string to that function.
---
 drivers/staging/lustre/lustre/ldlm/ldlm_internal.h |  2 --
 drivers/staging/lustre/lustre/ldlm/ldlm_pool.c     | 16 ++++------------
 2 files changed, 4 insertions(+), 14 deletions(-)

diff --git a/drivers/staging/lustre/lustre/ldlm/ldlm_internal.h b/drivers/staging/lustre/lustre/ldlm/ldlm_internal.h
index d8dcf8a73e4b..c907d880274d 100644
--- a/drivers/staging/lustre/lustre/ldlm/ldlm_internal.h
+++ b/drivers/staging/lustre/lustre/ldlm/ldlm_internal.h
@@ -31,8 +31,6 @@
  * Lustre is a trademark of Sun Microsystems, Inc.
  */
 
-#define MAX_STRING_SIZE 128
-
 extern int ldlm_srv_namespace_nr;
 extern int ldlm_cli_namespace_nr;
 extern struct mutex ldlm_srv_namespace_lock;
diff --git a/drivers/staging/lustre/lustre/ldlm/ldlm_pool.c b/drivers/staging/lustre/lustre/ldlm/ldlm_pool.c
index 5b23767faecf..adc3f3737daa 100644
--- a/drivers/staging/lustre/lustre/ldlm/ldlm_pool.c
+++ b/drivers/staging/lustre/lustre/ldlm/ldlm_pool.c
@@ -505,7 +505,7 @@ LUSTRE_RW_ATTR(lock_volume_factor);
 
 #define LDLM_POOL_ADD_VAR(name, var, ops)			\
 	do {							\
-		snprintf(var_name, MAX_STRING_SIZE, #name);	\
+		pool_vars[0].name = #name;			\
 		pool_vars[0].data = var;			\
 		pool_vars[0].fops = ops;			\
 		ldebugfs_add_vars(pl->pl_debugfs_entry, pool_vars, NULL);\
@@ -557,25 +557,18 @@ static int ldlm_pool_debugfs_init(struct ldlm_pool *pl)
 						 ns_pool);
 	struct dentry *debugfs_ns_parent;
 	struct lprocfs_vars pool_vars[2];
-	char *var_name = NULL;
 	int rc = 0;
 
-	var_name = kzalloc(MAX_STRING_SIZE + 1, GFP_NOFS);
-	if (!var_name)
-		return -ENOMEM;
-
 	debugfs_ns_parent = ns->ns_debugfs_entry;
 	if (IS_ERR_OR_NULL(debugfs_ns_parent)) {
 		CERROR("%s: debugfs entry is not initialized\n",
 		       ldlm_ns_name(ns));
 		rc = -EINVAL;
-		goto out_free_name;
+		goto out;
 	}
 	pl->pl_debugfs_entry = debugfs_create_dir("pool", debugfs_ns_parent);
 
-	var_name[MAX_STRING_SIZE] = '\0';
 	memset(pool_vars, 0, sizeof(pool_vars));
-	pool_vars[0].name = var_name;
 
 	LDLM_POOL_ADD_VAR(state, pl, &lprocfs_pool_state_fops);
 
@@ -583,7 +576,7 @@ static int ldlm_pool_debugfs_init(struct ldlm_pool *pl)
 					   LDLM_POOL_FIRST_STAT, 0);
 	if (!pl->pl_stats) {
 		rc = -ENOMEM;
-		goto out_free_name;
+		goto out;
 	}
 
 	lprocfs_counter_init(pl->pl_stats, LDLM_POOL_GRANTED_STAT,
@@ -622,8 +615,7 @@ static int ldlm_pool_debugfs_init(struct ldlm_pool *pl)
 	debugfs_create_file("stats", 0644, pl->pl_debugfs_entry, pl->pl_stats,
 			    &lprocfs_stats_seq_fops);
 
-out_free_name:
-	kfree(var_name);
+out:
 	return rc;
 }

Patch
diff mbox series

diff --git a/drivers/staging/lustre/lustre/ldlm/ldlm_resource.c b/drivers/staging/lustre/lustre/ldlm/ldlm_resource.c
index 74c7644d6ef8..261857e4540d 100644
--- a/drivers/staging/lustre/lustre/ldlm/ldlm_resource.c
+++ b/drivers/staging/lustre/lustre/ldlm/ldlm_resource.c
@@ -392,8 +392,6 @@  static int ldlm_namespace_debugfs_register(struct ldlm_namespace *ns)
 	return 0;
 }
 
-#undef MAX_STRING_SIZE
-
 struct ldlm_resource *ldlm_resource_getref(struct ldlm_resource *res)
 {
 	LASSERT(res);
diff --git a/drivers/staging/lustre/lustre/llite/llite_lib.c b/drivers/staging/lustre/lustre/llite/llite_lib.c
index d97abbfddccf..fda6d9b07952 100644
--- a/drivers/staging/lustre/lustre/llite/llite_lib.c
+++ b/drivers/staging/lustre/lustre/llite/llite_lib.c
@@ -906,8 +906,6 @@  void ll_lli_init(struct ll_inode_info *lli)
 	memset(lli->lli_jobid, 0, LUSTRE_JOBID_SIZE);
 }
 
-#define MAX_STRING_SIZE 128
-
 int ll_fill_super(struct super_block *sb)
 {
 	struct lustre_profile *lprof = NULL;
@@ -916,7 +914,7 @@  int ll_fill_super(struct super_block *sb)
 	char *dt = NULL, *md = NULL;
 	char *profilenm = get_profile_name(sb);
 	struct config_llog_instance *cfg;
-	char name[MAX_STRING_SIZE];
+	char name[128];
 	char *ptr;
 	int len;
 	int err;
@@ -960,7 +958,7 @@  int ll_fill_super(struct super_block *sb)
 		len -= 7;
 
 	/* Mount info */
-	snprintf(name, MAX_STRING_SIZE, "%.*s-%px", len,
+	snprintf(name, sizeof(name), "%.*s-%px", len,
 		 lsi->lsi_lmd->lmd_profile, sb);
 
 	/* Call ll_debugsfs_register_super() before lustre_process_log()
diff --git a/drivers/staging/lustre/lustre/llite/lproc_llite.c b/drivers/staging/lustre/lustre/llite/lproc_llite.c
index db2fbf1f3a50..5ed703d7bb1e 100644
--- a/drivers/staging/lustre/lustre/llite/lproc_llite.c
+++ b/drivers/staging/lustre/lustre/llite/lproc_llite.c
@@ -1187,8 +1187,6 @@  static struct lprocfs_vars lprocfs_llite_obd_vars[] = {
 	{ NULL }
 };
 
-#define MAX_STRING_SIZE 128
-
 static struct attribute *llite_attrs[] = {
 	&lustre_attr_blocksize.attr,
 	&lustre_attr_stat_blocksize.attr,
@@ -1434,8 +1432,6 @@  void ll_debugfs_unregister_super(struct super_block *sb)
 	lprocfs_free_stats(&sbi->ll_stats);
 }
 
-#undef MAX_STRING_SIZE
-
 #define pct(a, b) (b ? a * 100 / b : 0)
 
 static void ll_display_extents_info(struct ll_rw_extents_info *io_extents,
diff --git a/drivers/staging/lustre/lustre/lmv/lmv_obd.c b/drivers/staging/lustre/lustre/lmv/lmv_obd.c
index 35dff0e96bf7..138e124bd05e 100644
--- a/drivers/staging/lustre/lustre/lmv/lmv_obd.c
+++ b/drivers/staging/lustre/lustre/lmv/lmv_obd.c
@@ -273,8 +273,6 @@  static int lmv_init_ea_size(struct obd_export *exp, u32 easize, u32 def_easize)
 	return rc;
 }
 
-#define MAX_STRING_SIZE 128
-
 static int lmv_connect_mdc(struct obd_device *obd, struct lmv_tgt_desc *tgt)
 {
 	struct lmv_obd *lmv = &obd->u.lmv;
diff --git a/drivers/staging/lustre/lustre/obdclass/lprocfs_status.c b/drivers/staging/lustre/lustre/obdclass/lprocfs_status.c
index aed33068ff3c..a179b0d6979e 100644
--- a/drivers/staging/lustre/lustre/obdclass/lprocfs_status.c
+++ b/drivers/staging/lustre/lustre/obdclass/lprocfs_status.c
@@ -271,8 +271,6 @@  static int lprocfs_no_percpu_stats;
 module_param(lprocfs_no_percpu_stats, int, 0644);
 MODULE_PARM_DESC(lprocfs_no_percpu_stats, "Do not alloc percpu data for lprocfs stats");
 
-#define MAX_STRING_SIZE 128
-
 /* lprocfs API calls */
 
 static const struct file_operations lprocfs_generic_fops = { };