Re: [PATCH 1/1] NFS: Fix /proc/PID/io read_bytes for buffered reads
From: Daire Byrne <hidden>
Date: 2023-03-14 20:28:33
Thanks Dave. I can confirm that this does indeed fix the reporting of /proc/PID/read_bytes for us. I actually applied it (cleanly) to our v5.18 based kernel as we use that in production on our render farm. We use the read_bytes in our post render statistics to help track per render IO. Tested-by: Daire Byrne <redacted> On Thu, 9 Mar 2023 at 19:00, Dave Wysochanski [off-list ref] wrote:
quoted hunk ↗ jump to hunk
Prior to commit 8786fde8421c ("Convert NFS from readpages to readahead"), nfs_readpages() used the old mm interface read_cache_pages() which called task_io_account_read() for each NFS page read. After this commit, nfs_readpages() is converted to nfs_readahead(), which now uses the new mm interface readahead_page(). The new interface requires callers to call task_io_account_read() themselves. In addition, to nfs_readahead() task_io_account_read() should also be called from nfs_read_folio(). Fixes: 8786fde8421c ("Convert NFS from readpages to readahead") Link: https://lore.kernel.org/linux-nfs/CAPt2mGNEYUk5u8V4abe=5MM5msZqmvzCVrtCP4Qw1n=gCHCnww@mail.gmail.com/ (local) Signed-off-by: Dave Wysochanski <redacted> --- fs/nfs/read.c | 3 +++ 1 file changed, 3 insertions(+)diff --git a/fs/nfs/read.c b/fs/nfs/read.c index c380cff4108e..e90988591df4 100644 --- a/fs/nfs/read.c +++ b/fs/nfs/read.c@@ -15,6 +15,7 @@ #include <linux/stat.h> #include <linux/mm.h> #include <linux/slab.h> +#include <linux/task_io_accounting_ops.h> #include <linux/pagemap.h> #include <linux/sunrpc/clnt.h> #include <linux/nfs_fs.h>@@ -337,6 +338,7 @@ int nfs_read_folio(struct file *file, struct folio *folio) trace_nfs_aop_readpage(inode, folio); nfs_inc_stats(inode, NFSIOS_VFSREADPAGE); + task_io_account_read(folio_size(folio)); /* * Try to flush any pending writes to the file..@@ -393,6 +395,7 @@ void nfs_readahead(struct readahead_control *ractl) trace_nfs_aop_readahead(inode, readahead_pos(ractl), nr_pages); nfs_inc_stats(inode, NFSIOS_VFSREADPAGES); + task_io_account_read(readahead_length(ractl)); ret = -ESTALE; if (NFS_STALE(inode)) --2.31.1