On Tue, Jun 22, 2021 at 10:06:30PM +0800, Jia He wrote: > Background > ========== > Linus suggested printing the full path of 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. > > Link: https://lkml.org/lkml/2021/5/18/1260 [1] > > 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. all test_print selftests, including the new '%14pD' '%-14pD' > 4. kasnprintf I believe you are talking about kasprintf(). > Changelog > ========= > v5: > - remove the RFC tag JFYI, when we drop RFC we usually start the series from v1. > - refine the commit msg/comments(by Petr, Andy) > - make using_scratch_space a new parameter of the test case Thanks for the update, I have found few minor things, please address them and feel free to add Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> > v4: > - don't support spec.precision anymore for '%pD' > - add Rasmus's patch into this series > > v3: > - implement new d_path_unsafe to use [buf, end] instead of stack space for > filling bytes (by Matthew) > - add new test cases for '%pD' > - drop patch "hmcdrv: remove the redundant directory path" before removing rfc. > > 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_unsafe() > lib/vsprintf.c: make '%pD' print the full path of file > lib/test_printf.c: add test cases for '%pD' > > Rasmus Villemoes (1): > lib/test_printf.c: split write-beyond-buffer check in two > > Documentation/core-api/printk-formats.rst | 5 +- > fs/d_path.c | 104 +++++++++++++++++++++- > include/linux/dcache.h | 1 + > lib/test_printf.c | 54 ++++++++--- > lib/vsprintf.c | 40 ++++++++- > 5 files changed, 184 insertions(+), 20 deletions(-) > > -- > 2.17.1 > -- With Best Regards, Andy Shevchenko