[PATCH v3 1/7] S390: Remove now superfluous sentinel elem from ctl_table arrays

Joel Granados via B4 Relay devnull+j.granados.samsung.com at kernel.org
Mon Oct 2 04:30:36 PDT 2023


From: Joel Granados <j.granados at samsung.com>

This commit comes at the tail end of a greater effort to remove the
empty elements at the end of the ctl_table arrays (sentinels) which will
reduce the overall build time size of the kernel and run time memory
bloat by ~64 bytes per sentinel (further information Link :
https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/)

Remove the sentinel element from appldata_table, s390dbf_table,
topology_ctl_table, cmm_table and page_table_sysctl. Reduced the memory
allocation in appldata_register_ops by 1 effectively removing the
sentinel from ops->ctl_table.

This removal is safe because register_sysctl_sz and register_sysctl use
the array size in addition to checking for the sentinel.

Tested-by: Alexander Gordeev <agordeev at linux.ibm.com>
Acked-by: Heiko Carstens <hca at linux.ibm.com>
Signed-off-by: Joel Granados <j.granados at samsung.com>
---
 arch/s390/appldata/appldata_base.c | 4 +---
 arch/s390/kernel/debug.c           | 1 -
 arch/s390/kernel/topology.c        | 1 -
 arch/s390/mm/cmm.c                 | 1 -
 arch/s390/mm/pgalloc.c             | 1 -
 5 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/arch/s390/appldata/appldata_base.c b/arch/s390/appldata/appldata_base.c
index 3b0994625652..c2978cb03b36 100644
--- a/arch/s390/appldata/appldata_base.c
+++ b/arch/s390/appldata/appldata_base.c
@@ -63,7 +63,6 @@ static struct ctl_table appldata_table[] = {
 		.mode		= S_IRUGO | S_IWUSR,
 		.proc_handler	= appldata_interval_handler,
 	},
-	{ },
 };
 
 /*
@@ -351,8 +350,7 @@ int appldata_register_ops(struct appldata_ops *ops)
 	if (ops->size > APPLDATA_MAX_REC_SIZE)
 		return -EINVAL;
 
-	/* The last entry must be an empty one */
-	ops->ctl_table = kcalloc(2, sizeof(struct ctl_table), GFP_KERNEL);
+	ops->ctl_table = kcalloc(1, sizeof(struct ctl_table), GFP_KERNEL);
 	if (!ops->ctl_table)
 		return -ENOMEM;
 
diff --git a/arch/s390/kernel/debug.c b/arch/s390/kernel/debug.c
index a85e0c3e7027..85328a0ef3b6 100644
--- a/arch/s390/kernel/debug.c
+++ b/arch/s390/kernel/debug.c
@@ -978,7 +978,6 @@ static struct ctl_table s390dbf_table[] = {
 		.mode		= S_IRUGO | S_IWUSR,
 		.proc_handler	= s390dbf_procactive,
 	},
-	{ }
 };
 
 static struct ctl_table_header *s390dbf_sysctl_header;
diff --git a/arch/s390/kernel/topology.c b/arch/s390/kernel/topology.c
index 68adf1de8888..be8467b25953 100644
--- a/arch/s390/kernel/topology.c
+++ b/arch/s390/kernel/topology.c
@@ -636,7 +636,6 @@ static struct ctl_table topology_ctl_table[] = {
 		.mode		= 0644,
 		.proc_handler	= topology_ctl_handler,
 	},
-	{ },
 };
 
 static int __init topology_init(void)
diff --git a/arch/s390/mm/cmm.c b/arch/s390/mm/cmm.c
index f47515313226..f8b13f247646 100644
--- a/arch/s390/mm/cmm.c
+++ b/arch/s390/mm/cmm.c
@@ -332,7 +332,6 @@ static struct ctl_table cmm_table[] = {
 		.mode		= 0644,
 		.proc_handler	= cmm_timeout_handler,
 	},
-	{ }
 };
 
 #ifdef CONFIG_CMM_IUCV
diff --git a/arch/s390/mm/pgalloc.c b/arch/s390/mm/pgalloc.c
index 07fc660a24aa..75e1039f2ec5 100644
--- a/arch/s390/mm/pgalloc.c
+++ b/arch/s390/mm/pgalloc.c
@@ -30,7 +30,6 @@ static struct ctl_table page_table_sysctl[] = {
 		.extra1		= SYSCTL_ZERO,
 		.extra2		= SYSCTL_ONE,
 	},
-	{ }
 };
 
 static int __init page_table_register_sysctl(void)

-- 
2.30.2




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