1) Fastpath deletions. When a file is being deleted, check to see if it
was so recently created that its inode has not yet been written to
disk. If so, the delete can proceed to immediately free the inode.
2) Background writes: No file or block allocations can be done while the
bitmap is being written to disk. To avoid these stalls, the bitmap is
copied to another buffer which is written thus leaving the original
available for futher allocations.
3) Link count tracking. Constantly track the difference in i_effnlink and
i_nlink so that inodes that have had no change other than i_effnlink
need not be written.
4) Identify buffers with rollback dependencies so that the buffer flushing
daemon can choose to skip over them.
of dirrem structure rather than the collaterally created freeblks
and freefile structures. Limit the rate of buffer dirtying by the
syncer process during periods of intense file removal.
check before the inode is unlocked while grabbing its parent directory.
Once it is unlocked, other operations may slip in that could make
the inode-is-flushed check fail. Allowing other writes to the inode
before returning from fsync does not break the semantics of fsync
since we have flushed everything that was dirty at the time of the
fsync call.
quite dangerous, since the process may hold locks at the point,
and if it is stopped in that tsleep the machine may hang. Because
the sleep is so short, the PCATCH is not required here, so it has
been removed. For the future, the FreeBSD team needs to decide
whether it is still reasonable to stop a process in tsleep, as that
may affect any other code that uses PCATCH while holding kernel locks.
Submitted by: Dmitrij Tejblum <tejblum@arc.hq.cti.ru>
Reviewed by: Kirk McKusick <mckusick@mckusick.com>
* lockstatus() and VOP_ISLOCKED() gets a new process argument and a new
return value: LK_EXCLOTHER, when the lock is held exclusively by another
process.
* The ASSERT_VOP_(UN)LOCKED family is extended to use what this gives them
* Extend the vnode_if.src format to allow more exact specification than
locked/unlocked.
This commit should not do any semantic changes unless you are using
DEBUG_VFS_LOCKS.
Discussed with: grog, mch, peter, phk
Reviewed by: peter
The same goes for CD drivers and tape drivers. In systems with mixed IDE
and SCSI, devices in the same priority class will be sorted in attach
order.
Also, the 'CCD' priority is now the 'ARRAY' priority, and a number of
drivers have been modified to use that priority.
This includes the necessary changes to all drivers, except the ATA drivers.
Soren will modify those separately.
This does not include and does not require any change in the devstat
version number, since no known userland applications use the priority
enumerations.
Reviewed by: msmith, sos, phk, jlemon, mjacob, bde
resource_list_release. This removes the dependancy on the
layout of ivars.
* Move set_resource, get_resource and delete_resource from
isa_if.m to bus_if.m.
* Simplify driver code by providing wrappers to those methods:
bus_set_resource(dev, type, rid, start, count);
bus_get_resource(dev, type, rid, startp, countp);
bus_get_resource_start(dev, type, rid);
bus_get_resource_count(dev, type, rid);
bus_delete_resource(dev, type, rid);
* Delete isa_get_rsrc and use bus_get_resource_start instead.
* Fix a stupid typo in isa_alloc_resource reported by Takahashi
Yoshihiro <nyan@FreeBSD.org>.
* Print a diagnostic message if we can't assign resources to a PnP
device.
* Change device_print_prettyname() so that it doesn't print
"(no driver assigned)-1" for anonymous devices.
have been there in the first place. A GENERIC kernel shrinks almost 1k.
Add a slightly different safetybelt under nostop for tty drivers.
Add some missing FreeBSD tags
This means that we will not have to have a bpf and a non-bpf version
of our driver modules.
This does not open any security hole, because the bpf core isn't loadable
The drivers left unchanged are the "cross platform" drivers where the respective
maintainers are urged to DTRT, whatever that may be.
Add a couple of missing FreeBSD tags.
Introduce BUF_STRATEGY(struct buf *, int flag) macro, and use it throughout.
please see comment in sys/conf.h about the flag argument.
Remove strategy argument from all the diskslice/label/bad144
implementations, it should be found from the dev_t.
Remove bogus and unused strategy1 routines.
Remove open/close arguments from dssize(). Pick them up from dev_t.
Remove unused and unfinished setgeom support from diskslice/label/bad144 code.
lockmgr locks. This commit should be functionally equivalent to the old
semantics. That is, all buffer locking is done with LK_EXCLUSIVE
requests. Changes to take advantage of LK_SHARED and LK_RECURSIVE will
be done in future commits.
a sync on the block device for the filesystem. That allows it to push the
bitmap blocks before the inode blocks which greatly reduces the number of
inode rollbacks that need to be done.
#define COMPAT_PCI_DRIVER(name,data) DATA_SET(pcidevice_set,data)
.. to 2.2.x and 3.x if people think it's worth it. Driver writers can do
this if it's not defined. (The reason for this is that I'm trying to
progressively eliminate use of linker_sets where it hurts modularity and
runtime load capability, and these DATA_SET's keep getting in the way.)
files at once on a filesystem running soft updates. The root of
the problem is that soft updates limits the amount of memory that
may be allocated to dependency structures so as to avoid hogging
kernel memory. The original algorithm just waited for the disk I/O
to catch up and reduce the number of dependencies. This new code
takes a much more aggressive approach. Basically there are two
resources that routinely hit the limit. Inode dependencies during
periods with a high file creation rate and file and block removal
dependencies during periods with a high file removal rate. I have
attacked these problems from two fronts. When the inode dependency
limits are reached, I pick a random inode dependency, UFS_UPDATE
it together with all the other dirty inodes contained within its
disk block and then write that disk block. This trick usually
clears 5-50 inode dependencies in a single disk I/O. For block and
file removal dependencies, I pick a random directory page that has
at least one remove pending and VOP_FSYNC its directory. That
releases all its removal dependencies to the work queue. To further
hasten things along, I also immediately start the work queue process
rather than waiting for its next one second scheduled run.
