As suggested by TODO note, convert 'struct cluster_msg' to
use union for message-specific arguments and so reduce the
memory footprint of the aforementioned structure from 48
to 32 bytes. Compile tested only.
Signed-off-by: Dmitry Antipov <dmantipov@xxxxxxxxx>
---
drivers/md/md-cluster.c | 56 +++++++++++++++++++++++------------------
1 file changed, 31 insertions(+), 25 deletions(-)
diff --git a/drivers/md/md-cluster.c b/drivers/md/md-cluster.c
index 94221d964d4f..d9902bcd92c7 100644
--- a/drivers/md/md-cluster.c
+++ b/drivers/md/md-cluster.c
@@ -109,11 +109,17 @@ enum msg_type {
struct cluster_msg {
__le32 type;
__le32 slot;
- /* TODO: Unionize this for smaller footprint */
- __le64 low;
- __le64 high;
- char uuid[16];
- __le32 raid_slot;
+ union {
+ __le64 size; /* BITMAP_RESIZE */
+ struct {
+ __le64 low;
+ __le64 high;
+ } resync; /* RESYNCING */
+ struct {
+ char uuid[16]; /* NEWDISK */
+ __le32 raid_slot;
+ } other; /* others */
+ } u;
};
static void sync_ast(void *arg)
@@ -522,8 +528,8 @@ static int process_add_new_disk(struct mddev *mddev, struct cluster_msg *cmsg)
int res = 0;
len = snprintf(disk_uuid, 64, "DEVICE_UUID=");
- sprintf(disk_uuid + len, "%pU", cmsg->uuid);
- snprintf(raid_slot, 16, "RAID_DISK=%d", le32_to_cpu(cmsg->raid_slot));
+ sprintf(disk_uuid + len, "%pU", cmsg->u.other.uuid);
+ snprintf(raid_slot, 16, "RAID_DISK=%d", le32_to_cpu(cmsg->u.other.raid_slot));
pr_info("%s:%d Sending kobject change with %s and %s\n", __func__, __LINE__, disk_uuid, raid_slot);
init_completion(&cinfo->newdisk_completion);
set_bit(MD_CLUSTER_WAITING_FOR_NEWDISK, &cinfo->state);
@@ -545,7 +551,7 @@ static void process_metadata_update(struct mddev *mddev, struct cluster_msg *msg
int got_lock = 0;
struct md_thread *thread;
struct md_cluster_info *cinfo = mddev->cluster_info;
- mddev->good_device_nr = le32_to_cpu(msg->raid_slot);
+ mddev->good_device_nr = le32_to_cpu(msg->u.other.raid_slot);
dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_CR);
@@ -564,7 +570,7 @@ static void process_remove_disk(struct mddev *mddev, struct cluster_msg *msg)
struct md_rdev *rdev;
rcu_read_lock();
- rdev = md_find_rdev_nr_rcu(mddev, le32_to_cpu(msg->raid_slot));
+ rdev = md_find_rdev_nr_rcu(mddev, le32_to_cpu(msg->u.other.raid_slot));
if (rdev) {
set_bit(ClusterRemove, &rdev->flags);
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
@@ -572,7 +578,7 @@ static void process_remove_disk(struct mddev *mddev, struct cluster_msg *msg)
}
else
pr_warn("%s: %d Could not find disk(%d) to REMOVE\n",
- __func__, __LINE__, le32_to_cpu(msg->raid_slot));
+ __func__, __LINE__, le32_to_cpu(msg->u.other.raid_slot));
rcu_read_unlock();
}
@@ -581,12 +587,12 @@ static void process_readd_disk(struct mddev *mddev, struct cluster_msg *msg)
struct md_rdev *rdev;
rcu_read_lock();
- rdev = md_find_rdev_nr_rcu(mddev, le32_to_cpu(msg->raid_slot));
+ rdev = md_find_rdev_nr_rcu(mddev, le32_to_cpu(msg->u.other.raid_slot));
if (rdev && test_bit(Faulty, &rdev->flags))
clear_bit(Faulty, &rdev->flags);
else
pr_warn("%s: %d Could not find disk(%d) which is faulty",
- __func__, __LINE__, le32_to_cpu(msg->raid_slot));
+ __func__, __LINE__, le32_to_cpu(msg->u.other.raid_slot));
rcu_read_unlock();
}
@@ -610,8 +616,8 @@ static int process_recvd_msg(struct mddev *mddev, struct cluster_msg *msg)
case RESYNCING:
set_bit(MD_RESYNCING_REMOTE, &mddev->recovery);
process_suspend_info(mddev, le32_to_cpu(msg->slot),
- le64_to_cpu(msg->low),
- le64_to_cpu(msg->high));
+ le64_to_cpu(msg->u.resync.low),
+ le64_to_cpu(msg->u.resync.high));
break;
case NEWDISK:
if (process_add_new_disk(mddev, msg))
@@ -627,9 +633,9 @@ static int process_recvd_msg(struct mddev *mddev, struct cluster_msg *msg)
__recover_slot(mddev, le32_to_cpu(msg->slot));
break;
case BITMAP_RESIZE:
- if (le64_to_cpu(msg->high) != mddev->pers->size(mddev, 0, 0))
+ if (le64_to_cpu(msg->u.size) != mddev->pers->size(mddev, 0, 0))
ret = mddev->bitmap_ops->resize(mddev,
- le64_to_cpu(msg->high),
+ le64_to_cpu(msg->u.size),
0, false);
break;
default:
@@ -1111,7 +1117,7 @@ static int metadata_update_finish(struct mddev *mddev)
break;
}
if (raid_slot >= 0) {
- cmsg.raid_slot = cpu_to_le32(raid_slot);
+ cmsg.u.other.raid_slot = cpu_to_le32(raid_slot);
ret = __sendmsg(cinfo, &cmsg);
} else
pr_warn("md-cluster: No good device id found to send\n");
@@ -1134,7 +1140,7 @@ static int update_bitmap_size(struct mddev *mddev, sector_t size)
int ret;
cmsg.type = cpu_to_le32(BITMAP_RESIZE);
- cmsg.high = cpu_to_le64(size);
+ cmsg.u.size = cpu_to_le64(size);
ret = sendmsg(cinfo, &cmsg, 0);
if (ret)
pr_err("%s:%d: failed to send BITMAP_RESIZE message (%d)\n",
@@ -1309,7 +1315,7 @@ static void update_size(struct mddev *mddev, sector_t old_dev_sectors)
break;
}
if (raid_slot >= 0) {
- cmsg.raid_slot = cpu_to_le32(raid_slot);
+ cmsg.u.other.raid_slot = cpu_to_le32(raid_slot);
/*
* We can only change capiticy after all the nodes can do it,
* so need to wait after other nodes already received the msg
@@ -1402,8 +1408,8 @@ static int resync_info_update(struct mddev *mddev, sector_t lo, sector_t hi)
/* Re-acquire the lock to refresh LVB */
dlm_lock_sync(cinfo->bitmap_lockres, DLM_LOCK_PW);
cmsg.type = cpu_to_le32(RESYNCING);
- cmsg.low = cpu_to_le64(lo);
- cmsg.high = cpu_to_le64(hi);
+ cmsg.u.resync.low = cpu_to_le64(lo);
+ cmsg.u.resync.high = cpu_to_le64(hi);
/*
* mddev_lock is held if resync_info_update is called from
@@ -1463,8 +1469,8 @@ static int add_new_disk(struct mddev *mddev, struct md_rdev *rdev)
memset(&cmsg, 0, sizeof(cmsg));
cmsg.type = cpu_to_le32(NEWDISK);
- memcpy(cmsg.uuid, uuid, 16);
- cmsg.raid_slot = cpu_to_le32(rdev->desc_nr);
+ memcpy(cmsg.u.other.uuid, uuid, 16);
+ cmsg.u.other.raid_slot = cpu_to_le32(rdev->desc_nr);
if (lock_comm(cinfo, 1))
return -EAGAIN;
ret = __sendmsg(cinfo, &cmsg);
@@ -1527,7 +1533,7 @@ static int remove_disk(struct mddev *mddev, struct md_rdev *rdev)
struct cluster_msg cmsg = {0};
struct md_cluster_info *cinfo = mddev->cluster_info;
cmsg.type = cpu_to_le32(REMOVE);
- cmsg.raid_slot = cpu_to_le32(rdev->desc_nr);
+ cmsg.u.other.raid_slot = cpu_to_le32(rdev->desc_nr);
return sendmsg(cinfo, &cmsg, 1);
}
@@ -1592,7 +1598,7 @@ static int gather_bitmaps(struct md_rdev *rdev)
struct md_cluster_info *cinfo = mddev->cluster_info;
cmsg.type = cpu_to_le32(RE_ADD);
- cmsg.raid_slot = cpu_to_le32(rdev->desc_nr);
+ cmsg.u.other.raid_slot = cpu_to_le32(rdev->desc_nr);
err = sendmsg(cinfo, &cmsg, 1);
if (err)
goto out;
--
2.50.1
