[PATCH 15/29] NFSD: dynamically allocate the nfsd-client shrinker
From: Qi Zheng <hidden>
Date: 2023-06-22 09:00:35
Also in:
dm-devel, dri-devel, intel-gfx, linux-arm-msm, linux-bcache, linux-btrfs, linux-ext4, linux-fsdevel, linux-mm, linux-nfs, linux-xfs, lkml
Subsystem:
filesystems (vfs and infrastructure), kernel nfsd, sunrpc, and lockd servers, the rest · Maintainers:
Alexander Viro, Christian Brauner, Chuck Lever, Jeff Layton, Linus Torvalds
In preparation for implementing lockless slab shrink, we need to dynamically allocate the nfsd-client shrinker, so that it can be freed asynchronously using kfree_rcu(). Then it doesn't need to wait for RCU read-side critical section when releasing the struct nfsd_net. Signed-off-by: Qi Zheng <redacted> --- fs/nfsd/netns.h | 2 +- fs/nfsd/nfs4state.c | 20 ++++++++++++-------- 2 files changed, 13 insertions(+), 9 deletions(-)
diff --git a/fs/nfsd/netns.h b/fs/nfsd/netns.h
index ec49b200b797..f669444d5336 100644
--- a/fs/nfsd/netns.h
+++ b/fs/nfsd/netns.h@@ -195,7 +195,7 @@ struct nfsd_net { int nfs4_max_clients; atomic_t nfsd_courtesy_clients; - struct shrinker nfsd_client_shrinker; + struct shrinker *nfsd_client_shrinker; struct work_struct nfsd_shrinker_work; };
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 6e61fa3acaf1..a06184270548 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c@@ -4388,8 +4388,7 @@ static unsigned long nfsd4_state_shrinker_count(struct shrinker *shrink, struct shrink_control *sc) { int count; - struct nfsd_net *nn = container_of(shrink, - struct nfsd_net, nfsd_client_shrinker); + struct nfsd_net *nn = shrink->private_data; count = atomic_read(&nn->nfsd_courtesy_clients); if (!count)
@@ -8094,14 +8093,19 @@ static int nfs4_state_create_net(struct net *net) INIT_WORK(&nn->nfsd_shrinker_work, nfsd4_state_shrinker_worker); get_net(net); - nn->nfsd_client_shrinker.scan_objects = nfsd4_state_shrinker_scan; - nn->nfsd_client_shrinker.count_objects = nfsd4_state_shrinker_count; - nn->nfsd_client_shrinker.seeks = DEFAULT_SEEKS; - - if (register_shrinker(&nn->nfsd_client_shrinker, "nfsd-client")) + nn->nfsd_client_shrinker = shrinker_alloc_and_init(nfsd4_state_shrinker_count, + nfsd4_state_shrinker_scan, + 0, DEFAULT_SEEKS, 0, + nn); + if (!nn->nfsd_client_shrinker) goto err_shrinker; + + if (register_shrinker(nn->nfsd_client_shrinker, "nfsd-client")) + goto err_register; return 0; +err_register: + shrinker_free(nn->nfsd_client_shrinker); err_shrinker: put_net(net); kfree(nn->sessionid_hashtbl);
@@ -8197,7 +8201,7 @@ nfs4_state_shutdown_net(struct net *net) struct list_head *pos, *next, reaplist; struct nfsd_net *nn = net_generic(net, nfsd_net_id); - unregister_shrinker(&nn->nfsd_client_shrinker); + unregister_and_free_shrinker(nn->nfsd_client_shrinker); cancel_work(&nn->nfsd_shrinker_work); cancel_delayed_work_sync(&nn->laundromat_work); locks_end_grace(&nn->nfsd4_manager);
--
2.30.2