Switch KM_SLEEP to KM_PUSHPAGE

This warning indicates the incorrect use of KM_SLEEP in a call
path which must use KM_PUSHPAGE to avoid deadlocking in direct
reclaim.  See commit b8d06fca089fae4680c3a552fc55c512bfb02202
for additional details.

  SPL: Fixing allocation for task txg_sync (6093) which
  used GFP flags 0x297bda7c with PF_NOFS set

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #917
Switch KM_SLEEP to KM_PUSHPAGE

This warning indicates the incorrect use of KM_SLEEP in a call
path which must use KM_PUSHPAGE to avoid deadlocking in direct
reclaim.  See commit b8d06fca089fae4680c3a552fc55c512bfb02202
for additional details.

  SPL: Fixing allocation for task txg_sync (6093) which
  used GFP flags 0x297bda7c with PF_NOFS set

Signed-off-by: Chris Dunlop <chris@onthe.net.au>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #917
Add zstreamdump(8) command to examine ZFS send streams.

Obtained from: illumos-gate revision 11935:538c866aaac6
Source: ssh://anonhg@hg.illumos.org/illumos-gate

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #905
Add libnvpair to mount_zfs dependencies

Commit e6f290535c2fff8b940c4eacb1c90cbc2cfc7508 added libzpool to
the mount_zfs dependencies.  This brought in the nvpair symbols
which are used by libzpool.  To resolve this include the libnvpair
library for mount_zfs even though mount_zfs doesn't directly
require any of these symbols.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #926
Switch KM_SLEEP to KM_PUSHPAGE

This warning indicates the incorrect use of KM_SLEEP in a call
path which must use KM_PUSHPAGE to avoid deadlocking in direct
reclaim.  See commit b8d06fca089fae4680c3a552fc55c512bfb02202
for additional details.

  SPL: Fixing allocation for task txg_sync (6093) which
  used GFP flags 0x297bda7c with PF_NOFS set

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #917
Improve AF hard disk detection

Use the bdev_physical_block_size() interface to determine the
minimize write size which can be issued without incurring a
read-modify-write operation.  This is used to set the ashift
correctly to prevent a performance penalty when using AF hard
disks.

Unfortunately, this interface isn't entirely reliable because
it's not uncommon for disks to misreport this value.  For this
reason you may still need to manually set your ashift with:

  zpool create -o ashift=12 ...

The solution to this in the upstream Illumos source was to add
a while list of known offending drives.  Maintaining such a list
will be a burden, but it still may be worth doing if we can
detect a large number of these drives.  This should be considered
as future work.

Reported-by: Richard Yao <ryao@cs.stonybrook.edu>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #916
Switch KM_SLEEP to KM_PUSHPAGE

This warning indicates the incorrect use of KM_SLEEP in a call
path which must use KM_PUSHPAGE to avoid deadlocking in direct
reclaim.  See commit b8d06fca089fae4680c3a552fc55c512bfb02202
for additional details.

  SPL: Fixing allocation for task txg_sync (6093) which
  used GFP flags 0x297bda7c with PF_NOFS set

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #917
Switch KM_SLEEP to KM_PUSHPAGE

This warning indicates the incorrect use of KM_SLEEP in a call
path which must use KM_PUSHPAGE to avoid deadlocking in direct
reclaim.  See commit b8d06fca089fae4680c3a552fc55c512bfb02202
for additional details.

  SPL: Fixing allocation for task txg_sync (6093) which
  used GFP flags 0x297bda7c with PF_NOFS set

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #917
Fix missing vdev names in zpool status output

Commit 858219c makes more sense down below in the 'if (verbose)'
section of the code.  Initially, buf and path will never point
to the same location.  Once 'path = buf' is set on a raidz vdev,
the code may drop into the verbose section depending on the
verbose flag.  In here, using a tmpbuf makes sense since now
'buf == path'.

This issue does not occur in the upstream Solaris code because
their implementations of snprintf() allow for buf and path to
be the same address.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #57
Disable page allocation warnings for ARC buffers

Buffers for the ARC are normally backed by the SPL virtual slab.
However, if memory is low, AND no slab objects are available,
AND a new slab cannot be quickly constructed a new emergency
object will be directly allocated.

These objects can be as large as order 5 on a system with 4k
pages.  And because they are allocated with KM_PUSHPAGE, to
avoid a potential deadlock, they are not allowed to initiate I/O
to satisfy the allocation.  This can result in the occasional
allocation failure.

However, since these allocations are allowed to block and
perform operations such as memory compaction they will eventually
succeed.  Since this is not unexpected (just unlikely) behavior
this patch disables the warning for the allocation failure.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #465
Increase the stack space in userspace.

In 1e33ac1e2677c898a0b5ef6207048c692cb51bf4, the maximum stack size for
userspace tools was set to 8k to mimic the available kernel stack size.

Unfortunately, due to differences in how the stack is used in userspace
vs kernel space, spurious stack overflows could occur in userspace
tools due to the limited stack size. This is especially true in ztest
when debugging is enabled.

This patch multiplies the userspace stack size by 4, which fixes the
stack overflow issues. This comes at the price of not being able to
catch stack size issues in userspace, but the previous solution proved
unreliable anyway.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Fixes #934.
Make ZFS filesystem id persistent across different machines

Use ZFS dataset fsid guid as a unique file system id, similar to what is
done on Illumos/OpenSolaris.

Signed-off-by: Cyril Plisko <cyril.plisko@mountall.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #888
Add zstreamdump .gitignore

When zstreamdump was merged in commit b79fc3f we failed to add
the needed .gitignore file.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Adjust ARC settings

I made the following observations when examining arc_status from a
i386 system suffering from low performance and heavy idle load:

	- memory_throttle_count was extremely high
	- mru_evict_metadata and mru_ghost_evict_metadata were high
	- mfu_evict_data == 0
	- mfu_ghost_size == 0
	- mfu_ghost_evict_data == 0
	- mfu_ghost_evict_metadata == 0
	- arc_meta_used == arc_meta_max, but much less than arc_meta_limit
	- c_max == c
	- c_max >> arc_p_min_shift == c_min

Upon comparsion with an amd64 system, I noticed the following:

	- memory_throttle_count was low
	- mfu_evict_data, mfu_ghost_size, mfu_ghost_evict_data and
		  mfu_ghost_evict_metadata were all greater than zero
	- arc_meta_used < arc_meta_max < arc_meta_limit
	- c_max >> arc_p_min_shift > c_min
	- c_max > c

After looking at the code, I decided to make a few changes. First, I am
changing the minimum value of c_min to 16MB to mimic the change made in
freebsd/freebsd-head@8a78bd4cc19835b58ed1a8fbb45635a274dab8e9. Second, I
am changing the code to consider the minimum of both virtual memory and
physical memory when accepting changes to zfs_arc_max.

My hope is that changing the minimum value of c_min will correct some of
the inconsistencies between amd64 and i386 systems.

Signed-off-by: Richard Yao <ryao@cs.stonybrook.edu>
Linux 3.6-rc1 Compatibility: Use .mkdir instead of .create in 3.3 compatibility check

Linux 3.6 modifies inode_operations->create's function prototype. This
causes an autotools Linux 3.3. compatibility check for a function
prototype change in create, mkdir and mknode to fail. The check that
Since mkdir and mknode are unchanged, we modify the check to examine it
instead.

Signed-off-by: Richard Yao <ryao@cs.stonybrook.edu>