Commit Graph

9 Commits

Author SHA1 Message Date
Graham Christensen dda702fd16
bash scripts: use /usr/bin/env for bash shebangs
Not all systems / distros have a `/bin/bash`, and these scripts are
more difficult to run at development time.

For example, my system is NixOS which doesn't have a /bin/bash. This
is not a problem for NixOS building ZFS as a package: the build
environment automatically replaces these shebangs with corrected
paths.

The problem is much more annoying at development time: either the
scripts don't run, or I correct them for my local machine and deal with
a perpetually dirty work tree.

Before committing this patch I confirmed there are existing scripts
which use `/usr/bin/env` to locate bash, so I am thinking this is a
safe transformation.

There are a handful of other shebangs in this repository which don't
work on my system. This patch is useful on its own specifically for
`commitcheck.sh`, otherwise I can't validate my commits before
submission.

Here are the remaining shebangs which NixOS systems won't have:

       1274 #!/bin/ksh -p
         91 #!/bin/ksh
         89 #! /bin/ksh -p
          2 #!/bin/sed -f
          1 #!/usr/bin/perl -w
          1 #!/usr/bin/ksh
          1 #!/bin/nawk -f

plus this which will create an invalid shebang in
`tests/zfs-tests/tests/functional/mv_files/mv_files_common.kshlib`:

        echo "#!/bin/ksh" > $TEST_BASE_DIR/exitsZero.ksh

I chose to leave those alone for now, and gauge the interest in this
much smaller patch first.

The fixes for these are easy enough by simply using `/usr/bin/env ksh`:

         91 #!/bin/ksh
          1 #!/usr/bin/ksh

The fix for the other set is much trickier. Quoting the GNU coreutils
manual:

    Most operating systems (e.g. GNU/Linux, BSDs) treat all text after
    the first space as a single argument. When using env in a script it
    is thus not possible to specify multiple arguments.

and not all `env`'s support arguments.

Mine (GNU Coreutils 8.31) does, though this feature is new since
April 2018, GNU Coreutils 8.30:
https://git.savannah.gnu.org/cgit/coreutils.git/commit/?id=668306ed86c8c79b0af0db8b9c882654ebb66db2

and worse, requires the -S argument:

    -S, --split-string=S  process and split S into separate arguments;
                          used to pass multiple arguments on shebang
                          lines

Example:

    $ seq 1 2 | $(nix-build '<nixpkgs>' -A coreutils)/bin/env "sort -nr"
    /nix/[...]-coreutils-8.31/bin/env: ‘sort -nr’: No such file or directory
    /nix/[...]-coreutils-8.31/bin/env: use -[v]S to pass options in shebang lines

    $ seq 1 2 | $(nix-build '<nixpkgs>' -A coreutils)/bin/env "-S sort -nr"
    2
    1

GNU Coreutils says FreeBSD's `env` does, though I wonder if FreeBSD's
would be unhappy with the `-S`:
https://www.gnu.org/software/coreutils/manual/html_node/env-invocation.html#env-invocation

BusyBox v1.30.1 does not, and does not have a `-S`-like option:

    $ seq 1 2 | $(nix-build '<nixpkgs>' -A busybox)/bin/env "sort -nr"
    env: can't execute 'sort -nr': No such file or directory

Toybox 0.8.1 also does not, and also does not have a `-S` option:

    $ seq 1 2 | $(nix-build '<nixpkgs>' -A toybox)/bin/env "sort -nr"
    env: exec sort -nr: No such file or directory

---

At any rate, if this patch merges and the remaining ~1,500 are updated,
the much larger patch should probably include a checkstyle-like test
asserting all new shebangs use `/usr/bin/env`. I also don't mind
dealing with NixOS weirdness if the project would prefer that.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Signed-off-by: Graham Christensen <graham@grahamc.com>
Closes #9893
2020-02-10 13:13:46 -08:00
Neal Gompa (ニール・ゴンパ) 4efb48eecb Bump commit subject length to 72 characters
There's not really a reason to keep the subject length so short,
since the reason to make it this short was for making nice renders
of a summary list of the git log. With 72 characters, this still
works out fine, so let's just raise it to that so that it's easier
to give slightly more descriptive change summaries.

Reviewed by: Matt Ahrens <mahrens@delphix.com>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Neal Gompa <ngompa@datto.com>
Closes #8250
2019-01-08 09:23:05 -08:00
Matt Ahrens 5d43cc9a59 OpenZFS 9689 - zfs range lock code should not be zpl-specific
The ZFS range locking code in zfs_rlock.c/h depends on ZPL-specific
data structures, specifically znode_t.  However, it's also used by
the ZVOL code, which uses a "dummy" znode_t to pass to the range
locking code.

We should clean this up so that the range locking code is generic
and can be used equally by ZPL and ZVOL, and also can be used by
future consumers that may need to run in userland (libzpool) as
well as the kernel.

Porting notes:
* Added missing sys/avl.h include to sys/zfs_rlock.h.
* Removed 'dbuf is within the locked range' ASSERTs from dmu_sync().
  This was needed because ztest does not yet use a locked_range_t.
* Removed "Approved by:" tag requirement from OpenZFS commit
  check to prevent needless warnings when integrating changes
  which has not been merged to illumos.
* Reverted free_list range lock changes which were originally
  needed to defer the cv_destroy() which was called immediately
  after cv_broadcast().  With d2733258 this should be safe but
  if not we may need to reintroduce this logic.
* Reverts: The following two commits were reverted and squashed in
  to this change in order to make it easier to apply OpenZFS 9689.
  - d88895a0, which removed the dummy znode from zvol_state
  - e3a07cd0, which updated ztest to use range locks
* Preserved optimized rangelock comparison function.  Preserved the
  rangelock free list.  The cv_destroy() function will block waiting
  for all processes in cv_wait() to be scheduled and drop their
  reference.  This is done to ensure it's safe to free the condition
  variable.  However, blocking while holding the rl->rl_lock mutex
  can result in a deadlock on Linux.  A free list is introduced to
  defer the cv_destroy() and kmem_free() until after the mutex is
  released.

Authored by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed by: Serapheim Dimitropoulos <serapheim.dimitro@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Brad Lewis <brad.lewis@delphix.com>
Ported-by: Brian Behlendorf <behlendorf1@llnl.gov>

OpenZFS-issue: https://illumos.org/issues/9689
OpenZFS-commit: https://github.com/openzfs/openzfs/pull/680
External-issue: DLPX-58662
Closes #7980
2018-10-11 10:19:33 -07:00
Brian Behlendorf a584ef2605
Direct IO support
Direct IO via the O_DIRECT flag was originally introduced in XFS by
IRIX for database workloads. Its purpose was to allow the database
to bypass the page and buffer caches to prevent unnecessary IO
operations (e.g.  readahead) while preventing contention for system
memory between the database and kernel caches.

On Illumos, there is a library function called directio(3C) that
allows user space to provide a hint to the file system that Direct IO
is useful, but the file system is free to ignore it. The semantics
are also entirely a file system decision. Those that do not
implement it return ENOTTY.

Since the semantics were never defined in any standard, O_DIRECT is
implemented such that it conforms to the behavior described in the
Linux open(2) man page as follows.

    1.  Minimize cache effects of the I/O.

    By design the ARC is already scan-resistant which helps mitigate
    the need for special O_DIRECT handling.  Data which is only
    accessed once will be the first to be evicted from the cache.
    This behavior is in consistent with Illumos and FreeBSD.

    Future performance work may wish to investigate the benefits of
    immediately evicting data from the cache which has been read or
    written with the O_DIRECT flag.  Functionally this behavior is
    very similar to applying the 'primarycache=metadata' property
    per open file.

    2. O_DIRECT _MAY_ impose restrictions on IO alignment and length.

    No additional alignment or length restrictions are imposed.

    3. O_DIRECT _MAY_ perform unbuffered IO operations directly
       between user memory and block device.

    No unbuffered IO operations are currently supported.  In order
    to support features such as transparent compression, encryption,
    and checksumming a copy must be made to transform the data.

    4. O_DIRECT _MAY_ imply O_DSYNC (XFS).

    O_DIRECT does not imply O_DSYNC for ZFS.  Callers must provide
    O_DSYNC to request synchronous semantics.

    5. O_DIRECT _MAY_ disable file locking that serializes IO
       operations.  Applications should avoid mixing O_DIRECT
       and normal IO or mmap(2) IO to the same file.  This is
       particularly true for overlapping regions.

    All I/O in ZFS is locked for correctness and this locking is not
    disabled by O_DIRECT.  However, concurrently mixing O_DIRECT,
    mmap(2), and normal I/O on the same file is not recommended.

This change is implemented by layering the aops->direct_IO operations
on the existing AIO operations.  Code already existed in ZFS on Linux
for bypassing the page cache when O_DIRECT is specified.

References:
  * http://xfs.org/docs/xfsdocs-xml-dev/XFS_User_Guide/tmp/en-US/html/ch02s09.html
  * https://blogs.oracle.com/roch/entry/zfs_and_directio
  * https://ext4.wiki.kernel.org/index.php/Clarifying_Direct_IO's_Semantics
  * https://illumos.org/man/3c/directio

Reviewed-by: Richard Elling <Richard.Elling@RichardElling.com>
Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #224 
Closes #7823
2018-08-27 10:04:21 -07:00
Brian Behlendorf 3da3488e63
Fix shellcheck v0.4.6 warnings
Resolve new warnings reported after upgrading to shellcheck
version 0.4.6.  This patch contains no functional changes.

* egrep is non-standard and deprecated. Use grep -E instead. [SC2196]
* Check exit code directly with e.g. 'if mycmd;', not indirectly
  with $?.  [SC2181]  Suppressed.

Reviewed-by: George Melikov <mail@gmelikov.ru>
Reviewed-by: Giuseppe Di Natale <dinatale2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #7040
2018-01-17 10:17:16 -08:00
Giuseppe Di Natale 69b229bd60 commitcheck: Multiple OpenZFS ports in commit
Allow commitcheck.sh to handle multiple OpenZFS ports in
a single commit. This is useful in the cases when a change
upstream has bug fixes and it makes sense to port them with
the original patch.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Reviewed-by: Chris Dunlop <chris@onthe.net.au>
Signed-off-by: Giuseppe Di Natale <dinatale2@llnl.gov>
Closes #6780
2017-10-26 10:23:58 -07:00
Giuseppe Di Natale 8dcaf243d7 Add Coverity defect fix commit checker support
Enable commitcheck.sh to test if a commit message is
in the expected format for a coverity defect fix.

Reviewed-by: George Melikov <mail@gmelikov.ru>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Giuseppe Di Natale <dinatale2@llnl.gov>
Closes #6777
2017-10-26 10:17:00 -07:00
Giuseppe Di Natale 3f2da6cb73 Prevent commitcheck.sh from running twice
A stray semicolon was causing commitcheck.sh
to run twice when running make checkstyle.
Updated regexes for matching tagged lines.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Signed-off-by: Giuseppe Di Natale <dinatale2@llnl.gov>
Closes #5952
2017-04-03 14:20:01 -07:00
Giuseppe Di Natale cb524aa23a Commit message format in contributing guidelines
Add the need to have a commit message with a specific
format to the contributing guidelines. Provide a script
to help enforce commit message style.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Signed-off-by: Giuseppe Di Natale <dinatale2@llnl.gov>
Closes #5943
2017-03-31 09:33:38 -07:00