Hi Jeff. Which testcase(or test method) do I use to know improved point from ESTALE error ? I want to know before & after using testcase with this patch-set. Thanks. 2012/7/26, Jeff Layton <jlayton@xxxxxxxxxx>: > This patchset is a respin of the one I sent on June 29th. The main > reason for the resend is to deal with some minor merge conflicts that > have cropped up due to recent changes. > > This series depends on the "audit" series that I sent earlier today. > It's also available via the "estale" branch of my git tree: > > git://git.samba.org/jlayton/linux.git estale > > The original cover letter text follows: > > ESTALE errors are a source of pain for many users, primarily those who > are doing work on NFS. When userspace provides a path to a syscall, then > there's really little excuse for returning ESTALE. If userspace gave us > a path that we had to lookup in order to do the call, then it's not > particularly helpful to return ESTALE just because that path went stale > before we could do the actual operation. > > We can and should do better here. The kernel should instead catch that > error and retry the lookup and call, while forcing a revalidation of all > dentries involved. > > Unfortunately fixing this requires touching the syscalls themselves, or > at least their immediate helper functions. Not all syscalls can be > retried -- only those that take a pathname as an argument. > > With this patchset, I've decided to take the relatively less > controversial approach of just having the kernel retry once when it gets > an ESTALE error. I still think that it's not as strong as it should be, > but it should improve the situation in many common cases. > > I've also tried to engineer this in such a way that if we do decide that > we need to retry more than once, then it should be easy to change that > later. This should cover all of the syscalls in fs/stat.c and > fs/namei.c. > > Once these are merged, I'll look at adding similar handling to other > path-based syscalls in a later set. A quick look shows that we have > about 50-odd path-based syscalls that will need similar handling, so > this is just a start. > > Jeff Layton (17): > vfs: add a retry_estale helper function to handle retries on ESTALE > vfs: add a kern_path_at function > vfs: make fstatat retry on ESTALE errors from getattr call > vfs: fix readlinkat to retry on ESTALE > vfs: remove user_path_at_empty > vfs: turn "empty" arg in getname_flags into a bool > vfs: add new "reval" argument to kern_path_create > vfs: fix mknodat to retry on ESTALE errors > vfs: fix mkdir to retry on ESTALE errors > vfs: fix symlinkat to retry on ESTALE errors > vfs: fix linkat to retry on ESTALE errors > vfs: make rmdir retry on ESTALE errors > vfs: make do_unlinkat retry on ESTALE errors > vfs: fix renameat to retry on ESTALE errors > vfs: remove user_path_parent > vfs: have do_sys_truncate retry once on an ESTALE error > vfs: have faccessat retry once on an ESTALE error > > drivers/base/devtmpfs.c | 7 +- > fs/namei.c | 407 > +++++++++++++++++++++++++++++------------------- > fs/open.c | 162 ++++++++++--------- > fs/stat.c | 44 ++++-- > include/linux/fs.h | 22 +++ > include/linux/namei.h | 4 +- > net/unix/af_unix.c | 3 +- > 7 files changed, 400 insertions(+), 249 deletions(-) > > -- > 1.7.11.2 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-nfs" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
