[PATCH 7/9] NFS: remove congestion control.
From: NeilBrown <hidden>
Date: 2022-01-27 02:49:11
Also in:
ceph-devel, linux-ext4, linux-f2fs-devel, linux-fsdevel, linux-mm, linux-nfs, lkml
Subsystem:
filesystems (vfs and infrastructure), nfs, sunrpc, and lockd clients, the rest · Maintainers:
Alexander Viro, Christian Brauner, Trond Myklebust, Anna Schumaker, Linus Torvalds
Linux no longer uses the bdi congestion tracking framework. So remove code from bdi which tries to support it. Also remove the "nfs_congestion_kb" sysctl. This is a user-visible change, but unlikely to be a problematic one. Signed-off-by: NeilBrown <redacted> --- fs/nfs/sysctl.c | 7 ------ fs/nfs/write.c | 53 +-------------------------------------------- include/linux/nfs_fs.h | 1 - include/linux/nfs_fs_sb.h | 1 - 4 files changed, 1 insertion(+), 61 deletions(-)
diff --git a/fs/nfs/sysctl.c b/fs/nfs/sysctl.c
index 7aea195ddb35..18f3ff77fd0c 100644
--- a/fs/nfs/sysctl.c
+++ b/fs/nfs/sysctl.c@@ -22,13 +22,6 @@ static struct ctl_table nfs_cb_sysctls[] = { .mode = 0644, .proc_handler = proc_dointvec_jiffies, }, - { - .procname = "nfs_congestion_kb", - .data = &nfs_congestion_kb, - .maxlen = sizeof(nfs_congestion_kb), - .mode = 0644, - .proc_handler = proc_dointvec, - }, { } };
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 987a187bd39a..1c22ea6f23c3 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c@@ -397,33 +397,8 @@ static int wb_priority(struct writeback_control *wbc) return ret; } -/* - * NFS congestion control - */ - -int nfs_congestion_kb; - -#define NFS_CONGESTION_ON_THRESH (nfs_congestion_kb >> (PAGE_SHIFT-10)) -#define NFS_CONGESTION_OFF_THRESH \ - (NFS_CONGESTION_ON_THRESH - (NFS_CONGESTION_ON_THRESH >> 2)) - -static void nfs_set_page_writeback(struct page *page) -{ - struct inode *inode = page_file_mapping(page)->host; - struct nfs_server *nfss = NFS_SERVER(inode); - int ret = test_set_page_writeback(page); - - WARN_ON_ONCE(ret != 0); - - if (atomic_long_inc_return(&nfss->writeback) > - NFS_CONGESTION_ON_THRESH) - set_bdi_congested(inode_to_bdi(inode), BLK_RW_ASYNC); -} - static void nfs_end_page_writeback(struct nfs_page *req) { - struct inode *inode = page_file_mapping(req->wb_page)->host; - struct nfs_server *nfss = NFS_SERVER(inode); bool is_done; is_done = nfs_page_group_sync_on_bit(req, PG_WB_END);
@@ -432,8 +407,6 @@ static void nfs_end_page_writeback(struct nfs_page *req) return; end_page_writeback(req->wb_page); - if (atomic_long_dec_return(&nfss->writeback) < NFS_CONGESTION_OFF_THRESH) - clear_bdi_congested(inode_to_bdi(inode), BLK_RW_ASYNC); } /*
@@ -617,7 +590,7 @@ static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio, if (IS_ERR(req)) goto out; - nfs_set_page_writeback(page); + set_page_writeback(page); WARN_ON_ONCE(test_bit(PG_CLEAN, &req->wb_flags)); /* If there is a fatal error that covers this write, just exit */
@@ -1850,7 +1823,6 @@ static void nfs_commit_release_pages(struct nfs_commit_data *data) struct nfs_page *req; int status = data->task.tk_status; struct nfs_commit_info cinfo; - struct nfs_server *nfss; while (!list_empty(&data->pages)) { req = nfs_list_entry(data->pages.next);
@@ -1891,9 +1863,6 @@ static void nfs_commit_release_pages(struct nfs_commit_data *data) /* Latency breaker */ cond_resched(); } - nfss = NFS_SERVER(data->inode); - if (atomic_long_read(&nfss->writeback) < NFS_CONGESTION_OFF_THRESH) - clear_bdi_congested(inode_to_bdi(data->inode), BLK_RW_ASYNC); nfs_init_cinfo(&cinfo, data->inode, data->dreq); nfs_commit_end(cinfo.mds);
@@ -2162,26 +2131,6 @@ int __init nfs_init_writepagecache(void) if (nfs_commit_mempool == NULL) goto out_destroy_commit_cache; - /* - * NFS congestion size, scale with available memory. - * - * 64MB: 8192k - * 128MB: 11585k - * 256MB: 16384k - * 512MB: 23170k - * 1GB: 32768k - * 2GB: 46340k - * 4GB: 65536k - * 8GB: 92681k - * 16GB: 131072k - * - * This allows larger machines to have larger/more transfers. - * Limit the default to 256M - */ - nfs_congestion_kb = (16*int_sqrt(totalram_pages())) << (PAGE_SHIFT-10); - if (nfs_congestion_kb > 256*1024) - nfs_congestion_kb = 256*1024; - return 0; out_destroy_commit_cache:
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index 02aa49323d1d..17045c229277 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h@@ -569,7 +569,6 @@ extern void nfs_complete_unlink(struct dentry *dentry, struct inode *); /* * linux/fs/nfs/write.c */ -extern int nfs_congestion_kb; extern int nfs_writepage(struct page *page, struct writeback_control *wbc); extern int nfs_writepages(struct address_space *, struct writeback_control *); extern int nfs_flush_incompatible(struct file *file, struct page *page);
diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index ca0959e51e81..3444ebbc63b6 100644
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h@@ -137,7 +137,6 @@ struct nfs_server { struct rpc_clnt * client_acl; /* ACL RPC client handle */ struct nlm_host *nlm_host; /* NLM client handle */ struct nfs_iostats __percpu *io_stats; /* I/O statistics */ - atomic_long_t writeback; /* number of writeback pages */ unsigned int flags; /* various flags */ /* The following are for internal use only. Also see uapi/linux/nfs_mount.h */