Commit Graph

13 Commits

Author SHA1 Message Date
Brian Behlendorf 460748d4ae
Switch from _Noreturn to __attribute__((noreturn))
Parts of the Linux kernel build system struggle with _Noreturn.  This
results in the following warnings when building on RHEL 8.5, and likely
other environments.  Switch to using the __attribute__((noreturn)).

  warning: objtool: dbuf_free_range()+0x2b8:
    return with modified stack frame
  warning: objtool: dbuf_free_range()+0x0:
    stack state mismatch: cfa1=7+40 cfa2=7+8
  ...
  WARNING: EXPORT symbol "arc_buf_size" [zfs.ko] version generation
    failed, symbol will not be versioned.
  WARNING: EXPORT symbol "spa_open" [zfs.ko] version generation
    failed, symbol will not be versioned.
  ...

Additionally, __thread_exit() has been renamed spl_thread_exit() and
made a static inline function.  This was needed because the kernel
will generate a warning for symbols which are __attribute__((noreturn))
and then exported with EXPORT_SYMBOL.

While we could continue to use _Noreturn in user space I've also
switched it to __attribute__((noreturn)) purely for consistency
throughout the code base.

Reviewed-by: Ryan Moeller <freqlabs@FreeBSD.org>
Reviewed-by: Brian Atkinson <batkinson@lanl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #13238
2022-03-23 08:51:00 -07:00
Alejandro Colomar db7f1a91de
Use _Noreturn (C11; GNU89) properly
A function that returns with no value is a different thing from a
function that doesn't return at all.  Those are two orthogonal
concepts, commonly confused.

pthread_create(3) expects a pointer to a start routine that has a
very precise prototype:

    void *(*start_routine)(void *);

However, other thread functions, such as kernel ones, expect:

    void (*start_routine)(void *);

Providing a different one is incorrect, and has only been working
because the ABIs happen to produce a compatible function.

We should use '_Noreturn void', since it's the natural type, and
then provide a '_Noreturn void *' wrapper for pthread functions.

For consistency, replace most cases of __NORETURN or
__attribute__((noreturn)) by _Noreturn.  _Noreturn is understood
by -std=gnu89, so it should be safe to use everywhere.

Ref: https://github.com/openzfs/zfs/pull/13110#discussion_r808450136
Ref: https://software.codidact.com/posts/285972
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Co-authored-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com>
Closes #13120
2022-03-04 16:25:22 -08:00
наб 7ada752a93 Clean up CSTYLEDs
69 CSTYLED BEGINs remain, appx. 30 of which can be removed if cstyle(1)
had a useful policy regarding
  CALL(ARG1,
  	ARG2,
  	ARG3);
above 2 lines. As it stands, it spits out *both*
  sysctl_os.c: 385: continuation line should be indented by 4 spaces
  sysctl_os.c: 385: indent by spaces instead of tabs
which is very cool

Another >10 could be fixed by removing "ulong" &al. handling.
I don't foresee anyone actually using it intentionally
(does it even exist in modern headers? why did it in the first place?).

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes #12993
2022-01-26 11:38:52 -08:00
Brian Behlendorf 0e6c493fec cppcheck: integrete cppcheck
In order for cppcheck to perform a proper analysis it needs to be
aware of how the sources are compiled (source files, include
paths/files, extra defines, etc).  All the needed information is
available from the Makefiles and can be leveraged with a generic
cppcheck Makefile target.  So let's add one.

Additional minor changes:

* Removing the cppcheck-suppressions.txt file.  With cppcheck 2.3
  and these changes it appears to no longer be needed.  Some inline
  suppressions were also removed since they appear not to be
  needed.  We can add them back if it turns out they're needed
  for older versions of cppcheck.

* Added the ax_count_cpus m4 macro to detect at configure time how
  many processors are available in order to run multiple cppcheck
  jobs.  This value is also now used as a replacement for nproc
  when executing the kernel interface checks.

* "PHONY =" line moved in to the Rules.am file which is included
  at the top of all Makefile.am's.  This is just convenient becase
  it allows us to use the += syntax to add phony targets.

* One upside of this integration worth mentioning is it now allows
  `make cppcheck` to be run in any directory to check that subtree.

* For the moment, cppcheck is not run against the FreeBSD specific
  kernel sources.  The cppcheck-FreeBSD target will need to be
  implemented and testing on FreeBSD to support this.

Reviewed-by: Ryan Moeller <ryan@ixsystems.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #11508
2021-01-26 16:12:26 -08:00
Ryan Libby d8a09b3a04
lua: avoid gcc -Wreturn-local-addr bug
Avoid a bug with gcc's -Wreturn-local-addr warning with some
obfuscation.  In buggy versions of gcc, if a return value is an
expression that involves the address of a local variable, and even if
that address is legally converted to a non-pointer type, a warning may
be emitted and the value of the address may be replaced with zero.
Howerver, buggy versions don't emit the warning or replace the value
when simply returning a local variable of non-pointer type.

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90737

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ryan Libby <rlibby@FreeBSD.org>
Closes #11337
2020-12-15 09:20:48 -08:00
Matthew Ahrens 3eabed74c0
Fix lua stack overflow on recursive call to gsub()
The `zfs program` subcommand invokes a LUA interpreter to run ZFS
"channel programs".  This interpreter runs in a constrained environment,
with defined memory limits.  The LUA stack (used for LUA functions that
call each other) is allocated in the kernel's heap, and is limited by
the `-m MEMORY-LIMIT` flag and the `zfs_lua_max_memlimit` module
parameter.  The C stack is used by certain LUA features that are
implemented in C.  The C stack is limited by `LUAI_MAXCCALLS=20`, which
limits call depth.

Some LUA C calls use more stack space than others, and `gsub()` uses an
unusually large amount.  With a programming trick, it can be invoked
recursively using the C stack (rather than the LUA stack).  This
overflows the 16KB Linux kernel stack after about 11 iterations, less
than the limit of 20.

One solution would be to decrease `LUAI_MAXCCALLS`.  This could be made
to work, but it has a few drawbacks:

1. The existing test suite does not pass with `LUAI_MAXCCALLS=10`.

2. There may be other LUA functions that use a lot of stack space, and
the stack space may change depending on compiler version and options.

This commit addresses the problem by adding a new limit on the amount of
free space (in bytes) remaining on the C stack while running the LUA
interpreter: `LUAI_MINCSTACK=4096`.  If there is less than this amount
of stack space remaining, a LUA runtime error is generated.

Reviewed-by: George Wilson <gwilson@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Ryan Moeller <ryan@ixsystems.com>
Reviewed-by: Allan Jude <allanjude@freebsd.org>
Reviewed-by: Serapheim Dimitropoulos <serapheim@delphix.com>
Signed-off-by: Matthew Ahrens <mahrens@delphix.com>
Closes #10611 
Closes #10613
2020-07-27 16:11:47 -07:00
Andrea Gelmini dd4bc569b9
Fix typos
Correct various typos in the comments and tests.

Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Closes #10423
2020-06-09 21:24:09 -07:00
Brian Behlendorf 487bddad67 cppcheck: (error) Address of local auto-variable assigned
Suppress autoVariables warnings in the lua interpreter.  The usage
here while unconventional in intentional and the same as upstream.

[module/lua/ldebug.c:327]: (error) Address of local auto-variable
    assigned to a function parameter.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #9732
2019-12-18 17:25:42 -08:00
Romain Dolbeau 4254e40729 Preliminary support for RV64G
This adds basic support for RISC-V, specifically RV64G.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Romain Dolbeau <romain.dolbeau@european-processor-initiative.eu>
Closes #9540
2019-11-06 10:56:09 -08:00
Matthew Macy cf2eba666e Add default case to lua kernel code
Some platforms, e.g. FreeBSD, support user space setjmp
semantics in kernel.

Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Reviewed-by: Ryan Moeller <ryan@ixsystems.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Closes #9450
2019-10-16 18:36:15 -07:00
Brian Behlendorf adf495e239
Fix channel programs on s390x
When adapting the original sources for s390x the JMP_BUF_CNT was
mistakenly halved due to an incorrect assumption of the size of
a unsigned long.  They are 8 bytes for the s390x architecture.
Increase JMP_BUF_CNT accordingly.

Authored-by: Don Brady <don.brady@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reported-by: Colin Ian King <canonical.com>
Tested-by: Colin Ian King <canonical.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #8992
Closes #9080
2019-07-28 18:15:26 -07:00
Don Brady fc5d4b6737 Increase code coverage for Lua libraries
Add test coverage for lua libraries
Remove dead code in Lua implementation

Signed-off-by: Don Brady <don.brady@delphix.com>
2018-02-08 15:29:38 -08:00
Chris Williamson d99a015343 OpenZFS 7431 - ZFS Channel Programs
Authored by: Chris Williamson <chris.williamson@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: John Kennedy <john.kennedy@delphix.com>
Reviewed by: Dan Kimmel <dan.kimmel@delphix.com>
Approved by: Garrett D'Amore <garrett@damore.org>
Ported-by: Don Brady <don.brady@delphix.com>
Ported-by: John Kennedy <john.kennedy@delphix.com>

OpenZFS-issue: https://www.illumos.org/issues/7431
OpenZFS-commit: https://github.com/openzfs/openzfs/commit/dfc11533

Porting Notes:
* The CLI long option arguments for '-t' and '-m' don't parse on linux
* Switched from kmem_alloc to vmem_alloc in zcp_lua_alloc
* Lua implementation is built as its own module (zlua.ko)
* Lua headers consumed directly by zfs code moved to 'include/sys/lua/'
* There is no native setjmp/longjump available in stock Linux kernel.
  Brought over implementations from illumos and FreeBSD
* The get_temporary_prop() was adapted due to VFS platform differences
* Use of inline functions in lua parser to reduce stack usage per C call
* Skip some ZFS Test Suite ZCP tests on sparc64 to avoid stack overflow
2018-02-08 15:28:18 -08:00