src-test2/sys/fs/devfs, branch release/7.0.0_cvs

This commit was manufactured by cvs2svn to create tag

2008-02-24T05:45:17Z

'RELENG_7_0_0_RELEASE'. This commit was manufactured to restore the state of the 7.0-RELEASE image.

MFC: Lock the vnode interlock while reading v_usecount to update

2008-01-12T00:13:33Z

si_usecount in a cdev in devfs_reclaim(). Approved by: re (gnn)

When we do open, we should lock the vnode exclusively. This fixes few races:

2007-07-26T16:58:09Z

- fifo race, where two threads assign v_fifoinfo, - v_writecount modifications, - v_object modifications, - and probably more... Discussed with: kib, ups Approved by: re (rwatson)

Since rev. 1.199 of sys/kern/kern_conf.c, the thread that calls

2007-07-03T17:42:37Z

destroy_dev() from d_close() cdev method would self-deadlock. devfs_close() bump device thread reference counter, and destroy_dev() sleeps, waiting for si_threadcount to reach zero for cdev without d_purge method. destroy_dev_sched() could be used instead from d_close(), to schedule execution of destroy_dev() in another context. The destroy_dev_sched_drain() function can be used to drain the scheduled calls to destroy_dev_sched(). Similarly, drain_dev_clone_events() drains the events clone to make sure no lingering devices are left after dev_clone event handler deregistered. make_dev_credf(MAKEDEV_REF) function should be used from dev_clone event handlers instead of make_dev()/make_dev_cred() to ensure that created device has reference counter bumped before cdev mutex is dropped inside make_dev(). Reviewed by: tegge (early versions), njl (programming interface) Debugging help and testing by: Peter Holm Approved by: re (kensmith)

Eliminate now-unused SUSER_ALLOWJAIL arguments to priv_check_cred(); in

2007-06-12T00:12:01Z

some cases, move to priv_check() if it was an operation on a thread and no other flags were present. Eliminate caller-side jail exception checking (also now-unused); jail privilege exception code now goes solely in kern_jail.c. We can't yet eliminate suser() due to some cases in the KAME code where a privilege check is performed and then used in many different deferred paths. Do, however, move those prototypes to priv.h. Reviewed by: csjp Obtained from: TrustedBSD Project

Revert UF_OPENING workaround for CURRENT.

2007-05-31T11:51:53Z

Change the VOP_OPEN(), vn_open() vnode operation and d_fdopen() cdev operation argument from being file descriptor index into the pointer to struct file. Proposed and reviewed by: jhb Reviewed by: daichi (unionfs) Approved by: re (kensmith)

Rename macdevfsdirent() to macdevfs() to synchronize with SEDarwin,

2007-04-23T13:36:54Z

where similar data structures exist to support devfs and the MAC Framework, but are named differently. Obtained from: TrustedBSD Project Sponsored by: SPARTA, Inc.

In some cases, like whenever devfs file times are zero, the fix(aa) will not

2007-04-20T01:47:05Z

be applied to dev entries. This leaves us with file times like "Jan 1 1970." Work around this problem by replacing the tv_sec == 0 check with a <= 3600 check. It's doubtful anyone will be booting within an hour of the Epoch, let alone care about a few seconds worth of nonzero timestamps. It's a hackish work around, but it does work and I have not experienced any negatives in my testing. Discussed with: bde "Ok with me: phk

Replace custom file descriptor array sleep lock constructed using a mutex

2007-04-04T09:11:34Z

and flags with an sxlock. This leads to a significant and measurable performance improvement as a result of access to shared locking for frequent lookup operations, reduced general overhead, and reduced overhead in the event of contention. All of these are imported for threaded applications where simultaneous access to a shared file descriptor array occurs frequently. Kris has reported 2x-4x transaction rate improvements on 8-core MySQL benchmarks; smaller improvements can be expected for many workloads as a result of reduced overhead. - Generally eliminate the distinction between "fast" and regular acquisisition of the filedesc lock; the plan is that they will now all be fast. Change all locking instances to either shared or exclusive locks. - Correct a bug (pointed out by kib) in fdfree() where previously msleep() was called without the mutex held; sx_sleep() is now always called with the sxlock held exclusively. - Universally hold the struct file lock over changes to struct file, rather than the filedesc lock or no lock. Always update the f_ops field last. A further memory barrier is required here in the future (discussed with jhb). - Improve locking and reference management in linux_at(), which fails to properly acquire vnode references before using vnode pointers. Annotate improper use of vn_fullpath(), which will be replaced at a future date. In fcntl(), we conservatively acquire an exclusive lock, even though in some cases a shared lock may be sufficient, which should be revisited. The dropping of the filedesc lock in fdgrowtable() is no longer required as the sxlock can be held over the sleep operation; we should consider removing that (pointed out by attilio). Tested by: kris Discussed with: jhb, kris, attilio, jeff

Annotate that this giant acqusition is dependent on tty locking.

2007-03-26T21:56:46Z