From: Jia He <justin.he@arm.com>
To: Linus Torvalds <torvalds@linux-foundation.org>,
Petr Mladek <pmladek@suse.com>,
Steven Rostedt <rostedt@goodmis.org>,
Sergey Senozhatsky <senozhatsky@chromium.org>,
Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
Rasmus Villemoes <linux@rasmusvillemoes.dk>,
Jonathan Corbet <corbet@lwn.net>,
Alexander Viro <viro@zeniv.linux.org.uk>,
Luca Coelho <luciano.coelho@intel.com>,
Kalle Valo <kvalo@codeaurora.org>,
"David S. Miller" <davem@davemloft.net>,
Jakub Kicinski <kuba@kernel.org>,
Heiko Carstens <hca@linux.ibm.com>,
Vasily Gorbik <gor@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>,
Johannes Berg <johannes.berg@intel.com>,
linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-wireless@vger.kernel.org, netdev@vger.kernel.org,
linux-s390@vger.kernel.org, Jia He <justin.he@arm.com>
Subject: [PATCH RFCv2 0/3] make '%pD' print full path for file
Date: Fri, 28 May 2021 19:39:48 +0800 [thread overview]
Message-ID: <20210528113951.6225-1-justin.he@arm.com> (raw)
Background
==========
Linus suggested printing full path for file instead of printing
the components as '%pd'.
Typically, there is no need for printk specifiers to take any real locks
(ie mount_lock or rename_lock). So I introduce a new helper d_path_fast
which is similar to d_path except it doesn't take any seqlock/spinlock.
This series is based on Al Viro's d_path cleanup patches [1] which
lifted the inner lockless loop into a new helper.
[1] https://lkml.org/lkml/2021/5/18/1260
Test
====
The cases I tested:
1. print '%pD' with full path of ext4 file
2. mount a ext4 filesystem upon a ext4 filesystem, and print the file
with '%pD'
3. print file path which has more than 256 chars,"-ENAMETOOLONG" will
be returned
4. print file path with '%32pD'
5. all test_print selftests
After this set, I found many lines containing '%pD[234]' should be changed
to '%pD'. I don't want to involve those subsystems in this patch series
before the helper is stable enough.
You can get the lines by:
$find fs/ -name \*.[ch] | xargs grep -rn "\%pD[234"
fs/overlayfs/file.c:65: pr_debug("open(%p[%pD2/%c], 0%o) -> (%p, 0%o)\n",
fs/nfs/direct.c:453: dfprintk(FILE, "NFS: direct read(%pD2, %zd@%Ld)\n",
fs/nfs/direct.c:908: dfprintk(FILE, "NFS: direct write(%pD2, %zd@%Ld)\n",
fs/nfs/write.c:1371: dprintk("NFS: nfs_updatepage(%pD2 %d@%lld)\n",
fs/nfs/nfs4file.c:116: dprintk("NFS: flush(%pD2)\n", file);
fs/nfs/file.c:69: dprintk("NFS: open file(%pD2)\n", filp);
fs/nfs/file.c:83: dprintk("NFS: release(%pD2)\n", filp);
fs/nfs/file.c:117: dprintk("NFS: llseek file(%pD2, %lld, %d)\n",
fs/nfs/file.c:145: dprintk("NFS: flush(%pD2)\n", file);
fs/nfs/file.c:166: dprintk("NFS: read(%pD2, %zu@%lu)\n",
fs/nfs/file.c:188: dprintk("NFS: mmap(%pD2)\n", file);
fs/nfs/file.c:213: dprintk("NFS: fsync file(%pD2) datasync %d\n", file, datasync);
fs/nfs/file.c:328: dfprintk(PAGECACHE, "NFS: write_begin(%pD2(%lu), %u@%lld)\n",
fs/nfs/file.c:360: dfprintk(PAGECACHE, "NFS: write_end(%pD2(%lu), %u@%lld)\n",
fs/nfs/file.c:551: dfprintk(PAGECACHE, "NFS: vm_page_mkwrite(%pD2(%lu), offset %lld)\n",
fs/nfs/file.c:621: dprintk("NFS: write(%pD2, %zu@%Ld)\n",
fs/nfs/file.c:803: dprintk("NFS: lock(%pD2, t=%x, fl=%x, r=%lld:%lld)\n",
fs/nfs/file.c:841: dprintk("NFS: flock(%pD2, t=%x, fl=%x)\n",
fs/nfs/dir.c:111: dfprintk(FILE, "NFS: open dir(%pD2)\n", filp);
fs/nfs/dir.c:456: pr_notice("NFS: directory %pD2 contains a readdir loop."
fs/nfs/dir.c:1084: dfprintk(FILE, "NFS: readdir(%pD2) starting at cookie %llu\n",
fs/nfs/dir.c:1158: dfprintk(FILE, "NFS: readdir(%pD2) returns %d\n", file, res);
fs/nfs/dir.c:1166: dfprintk(FILE, "NFS: llseek dir(%pD2, %lld, %d)\n",
fs/nfs/dir.c:1208: dfprintk(FILE, "NFS: fsync dir(%pD2) datasync %d\n", filp, datasync);
fs/nfsd/nfs4state.c:2439: seq_printf(s, "filename: \"%pD2\"", f->nf_file);
fs/exec.c:817: pr_warn_once("process '%pD4' started with executable stack\n",
fs/iomap/direct-io.c:429: pr_warn_ratelimited("Direct I/O collision with buffered writes! File: %pD4 Comm: %.20s\n",
fs/ioctl.c:81: pr_warn_ratelimited("[%s/%d] FS: %s File: %pD4 would truncate fibmap result\n",
fs/read_write.c:425: "kernel %s not supported for file %pD4 (pid: %d comm: %.20s)\n",
fs/splice.c:754: "splice %s not supported for file %pD4 (pid: %d comm: %.20s)\n",
fs/afs/mntpt.c:64: _enter("%p,%p{%pD2}", inode, file, file);
Changelog:
v2:
- implement new d_path_fast based on Al Viro's patches
- add check_pointer check (by Petr)
- change the max full path size to 256 in stack space
v1: https://lkml.org/lkml/2021/5/8/122
Jia He (3):
fs: introduce helper d_path_fast()
lib/vsprintf.c: make %pD print full path for file
s390/hmcdrv: remove the redundant directory path in debug message
Documentation/core-api/printk-formats.rst | 5 +++--
drivers/s390/char/hmcdrv_dev.c | 10 +++++-----
fs/d_path.c | 21 +++++++++++++++++++++
include/linux/dcache.h | 1 +
lib/vsprintf.c | 21 +++++++++++++++++----
5 files changed, 47 insertions(+), 11 deletions(-)
--
2.17.1
next reply other threads:[~2021-05-28 11:40 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-05-28 11:39 Jia He [this message]
2021-05-28 11:39 ` [PATCH RFCv2 1/3] fs: introduce helper d_path_fast() Jia He
2021-05-28 12:44 ` Al Viro
2021-05-28 12:51 ` Matthew Wilcox
2021-05-28 14:23 ` Justin He
2021-05-28 11:39 ` [PATCH RFCv2 2/3] lib/vsprintf.c: make %pD print full path for file Jia He
2021-05-28 12:59 ` Matthew Wilcox
2021-05-28 14:22 ` Justin He
2021-05-28 14:52 ` Matthew Wilcox
2021-05-28 15:09 ` Justin He
2021-05-28 15:22 ` Matthew Wilcox
2021-05-31 0:39 ` Justin He
2021-06-01 14:42 ` Justin He
2021-06-01 15:30 ` Matthew Wilcox
2021-06-01 15:36 ` Andy Shevchenko
2021-06-01 15:44 ` Matthew Wilcox
2021-06-01 15:53 ` Andy Shevchenko
2021-06-01 16:10 ` Andy Shevchenko
2021-06-01 17:05 ` Matthew Wilcox
2021-06-01 19:01 ` Rasmus Villemoes
2021-06-02 5:47 ` Justin He
2021-05-28 20:06 ` Rasmus Villemoes
2021-05-30 15:18 ` Matthew Wilcox
2021-05-31 9:40 ` Petr Mladek
2021-05-28 11:39 ` [PATCH RFCv2 3/3] s390/hmcdrv: remove the redundant directory path in debug message Jia He
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210528113951.6225-1-justin.he@arm.com \
--to=justin.he@arm.com \
--cc=andriy.shevchenko@linux.intel.com \
--cc=borntraeger@de.ibm.com \
--cc=corbet@lwn.net \
--cc=davem@davemloft.net \
--cc=gor@linux.ibm.com \
--cc=hca@linux.ibm.com \
--cc=johannes.berg@intel.com \
--cc=kuba@kernel.org \
--cc=kvalo@codeaurora.org \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-s390@vger.kernel.org \
--cc=linux-wireless@vger.kernel.org \
--cc=linux@rasmusvillemoes.dk \
--cc=luciano.coelho@intel.com \
--cc=netdev@vger.kernel.org \
--cc=pmladek@suse.com \
--cc=rostedt@goodmis.org \
--cc=senozhatsky@chromium.org \
--cc=torvalds@linux-foundation.org \
--cc=viro@zeniv.linux.org.uk \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).