lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

pnfs: change lo refcounting to atomic_t

Browse Source 
This will be required to allow us to grab reference outside of i_lock.
While we are at it, make put_layout_hdr take the same argument as all the
related functions.

Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This commit is contained in:
Fred Isaman
2011-01-06 11:36:28 +00:00
committed by Trond Myklebust
parent fc1794c5b0
commit cc6e5340b0
2 changed files with 28 additions and 24 deletions
Download Patch File Download Diff File Expand all files Collapse all files

48
fs/nfs/pnfs.c
View File

@@ -177,34 +177,38 @@ EXPORT_SYMBOL_GPL(pnfs_unregister_layoutdriver);
* pNFS client layout cache * pNFS client layout cache
*/ */
/* Need to hold i_lock if caller does not already hold reference */
static void static void
get_layout_hdr_locked(struct pnfs_layout_hdr *lo) get_layout_hdr(struct pnfs_layout_hdr *lo)
{ {
assert_spin_locked(&lo->plh_inode->i_lock); atomic_inc(&lo->plh_refcount);
lo->plh_refcount++; }
static void
destroy_layout_hdr(struct pnfs_layout_hdr *lo)
{
dprintk("%s: freeing layout cache %p\n", __func__, lo);
BUG_ON(!list_empty(&lo->plh_layouts));
NFS_I(lo->plh_inode)->layout = NULL;
kfree(lo);
} }
static void static void
put_layout_hdr_locked(struct pnfs_layout_hdr *lo) put_layout_hdr_locked(struct pnfs_layout_hdr *lo)
{ {
assert_spin_locked(&lo->plh_inode->i_lock); if (atomic_dec_and_test(&lo->plh_refcount))
BUG_ON(lo->plh_refcount == 0); destroy_layout_hdr(lo);
lo->plh_refcount--;
if (!lo->plh_refcount) {
dprintk("%s: freeing layout cache %p\n", __func__, lo);
BUG_ON(!list_empty(&lo->plh_layouts));
NFS_I(lo->plh_inode)->layout = NULL;
kfree(lo);
}
} }
void void
put_layout_hdr(struct inode *inode) put_layout_hdr(struct pnfs_layout_hdr *lo)
{ {
spin_lock(&inode->i_lock); struct inode *inode = lo->plh_inode;
put_layout_hdr_locked(NFS_I(inode)->layout);
spin_unlock(&inode->i_lock); if (atomic_dec_and_lock(&lo->plh_refcount, &inode->i_lock)) {
destroy_layout_hdr(lo);
spin_unlock(&inode->i_lock);
}
} }
static void static void
@@ -223,7 +227,7 @@ static void free_lseg(struct pnfs_layout_segment *lseg)
NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg); NFS_SERVER(ino)->pnfs_curr_ld->free_lseg(lseg);
/* Matched by get_layout_hdr in pnfs_insert_layout */ /* Matched by get_layout_hdr in pnfs_insert_layout */
put_layout_hdr(ino); put_layout_hdr(NFS_I(ino)->layout);
} }
/* The use of tmp_list is necessary because pnfs_curr_ld->free_lseg /* The use of tmp_list is necessary because pnfs_curr_ld->free_lseg
@@ -490,7 +494,7 @@ pnfs_insert_layout(struct pnfs_layout_hdr *lo,
__func__, lseg, lseg->pls_range.iomode, __func__, lseg, lseg->pls_range.iomode,
lseg->pls_range.offset, lseg->pls_range.length); lseg->pls_range.offset, lseg->pls_range.length);
} }
get_layout_hdr_locked(lo); get_layout_hdr(lo);
dprintk("%s:Return\n", __func__); dprintk("%s:Return\n", __func__);
} }
@@ -503,7 +507,7 @@ alloc_init_layout_hdr(struct inode *ino)
lo = kzalloc(sizeof(struct pnfs_layout_hdr), GFP_KERNEL); lo = kzalloc(sizeof(struct pnfs_layout_hdr), GFP_KERNEL);
if (!lo) if (!lo)
return NULL; return NULL;
lo->plh_refcount = 1; atomic_set(&lo->plh_refcount, 1);
INIT_LIST_HEAD(&lo->plh_layouts); INIT_LIST_HEAD(&lo->plh_layouts);
INIT_LIST_HEAD(&lo->plh_segs); INIT_LIST_HEAD(&lo->plh_segs);
lo->plh_inode = ino; lo->plh_inode = ino;
@@ -618,7 +622,7 @@ pnfs_update_layout(struct inode *ino,
goto out_unlock; goto out_unlock;
atomic_inc(&lo->plh_outstanding); atomic_inc(&lo->plh_outstanding);
get_layout_hdr_locked(lo); get_layout_hdr(lo);
if (list_empty(&lo->plh_segs)) { if (list_empty(&lo->plh_segs)) {
/* The lo must be on the clp list if there is any /* The lo must be on the clp list if there is any
* chance of a CB_LAYOUTRECALL(FILE) coming in. * chance of a CB_LAYOUTRECALL(FILE) coming in.
@@ -641,7 +645,7 @@ pnfs_update_layout(struct inode *ino,
spin_unlock(&ino->i_lock); spin_unlock(&ino->i_lock);
} }
atomic_dec(&lo->plh_outstanding); atomic_dec(&lo->plh_outstanding);
put_layout_hdr(ino); put_layout_hdr(lo);
out: out:
dprintk("%s end, state 0x%lx lseg %p\n", __func__, dprintk("%s end, state 0x%lx lseg %p\n", __func__,
nfsi->layout->plh_flags, lseg); nfsi->layout->plh_flags, lseg);

4
fs/nfs/pnfs.h
View File

@@ -65,7 +65,7 @@ struct pnfs_layoutdriver_type {
}; };
struct pnfs_layout_hdr { struct pnfs_layout_hdr {
unsigned long plh_refcount; atomic_t plh_refcount;
struct list_head plh_layouts; /* other client layouts */ struct list_head plh_layouts; /* other client layouts */
struct list_head plh_segs; /* layout segments list */ struct list_head plh_segs; /* layout segments list */
nfs4_stateid plh_stateid; nfs4_stateid plh_stateid;
@@ -147,7 +147,7 @@ void unset_pnfs_layoutdriver(struct nfs_server *);
int pnfs_layout_process(struct nfs4_layoutget *lgp); int pnfs_layout_process(struct nfs4_layoutget *lgp);
void pnfs_destroy_layout(struct nfs_inode *); void pnfs_destroy_layout(struct nfs_inode *);
void pnfs_destroy_all_layouts(struct nfs_client *); void pnfs_destroy_all_layouts(struct nfs_client *);
void put_layout_hdr(struct inode *inode); void put_layout_hdr(struct pnfs_layout_hdr *lo);
int pnfs_choose_layoutget_stateid(nfs4_stateid *dst, int pnfs_choose_layoutget_stateid(nfs4_stateid *dst,
struct pnfs_layout_hdr *lo, struct pnfs_layout_hdr *lo,
struct nfs4_state *open_state); struct nfs4_state *open_state);