linux/kernel
Linus Torvalds afa4bb778e workqueue: clean up WORK_* constant types, clarify masking
Dave Airlie reports that gcc-13.1.1 has started complaining about some
of the workqueue code in 32-bit arm builds:

  kernel/workqueue.c: In function ‘get_work_pwq’:
  kernel/workqueue.c:713:24: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
    713 |                 return (void *)(data & WORK_STRUCT_WQ_DATA_MASK);
        |                        ^
  [ ... a couple of other cases ... ]

and while it's not immediately clear exactly why gcc started complaining
about it now, I suspect it's some C23-induced enum type handlign fixup in
gcc-13 is the cause.

Whatever the reason for starting to complain, the code and data types
are indeed disgusting enough that the complaint is warranted.

The wq code ends up creating various "helper constants" (like that
WORK_STRUCT_WQ_DATA_MASK) using an enum type, which is all kinds of
confused.  The mask needs to be 'unsigned long', not some unspecified
enum type.

To make matters worse, the actual "mask and cast to a pointer" is
repeated a couple of times, and the cast isn't even always done to the
right pointer, but - as the error case above - to a 'void *' with then
the compiler finishing the job.

That's now how we roll in the kernel.

So create the masks using the proper types rather than some ambiguous
enumeration, and use a nice helper that actually does the type
conversion in one well-defined place.

Incidentally, this magically makes clang generate better code.  That,
admittedly, is really just a sign of clang having been seriously
confused before, and cleaning up the typing unconfuses the compiler too.

Reported-by: Dave Airlie <airlied@gmail.com>
Link: https://lore.kernel.org/lkml/CAPM=9twNnV4zMCvrPkw3H-ajZOH-01JVh_kDrxdPYQErz8ZTdA@mail.gmail.com/
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Tejun Heo <tj@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2023-06-23 12:08:14 -07:00
..
bpf bpf: Force kprobe multi expected_attach_type for kprobe_multi link 2023-06-21 10:40:26 +02:00
cgroup cgroup: Do not corrupt task iteration when rebinding subsystem 2023-06-12 07:21:57 -10:00
configs Char/Misc drivers for 6.4-rc1 2023-04-27 12:07:50 -07:00
debug
dma dma-mapping updates for Linux 6.4 2023-04-29 10:29:57 -07:00
entry ptrace: Provide set/get interface for syscall user dispatch 2023-04-16 14:23:07 +02:00
events perf/core: Fix perf_sample_data not properly initialized for different swevents in perf_tp_event() 2023-05-08 10:58:26 +02:00
futex
gcov
irq xen: branch for v6.4-rc4 2023-05-27 09:42:56 -07:00
kcsan - Nick Piggin's "shoot lazy tlbs" series, to improve the peformance of 2023-04-27 19:42:02 -07:00
livepatch Scheduler changes for v6.4: 2023-04-28 14:53:30 -07:00
locking Two fixes for debugobjects: 2023-05-28 07:15:33 -04:00
module module/decompress: Fix error checking on zstd decompression 2023-06-01 14:36:46 -07:00
power More power management updates for 6.4-rc1 2023-05-03 12:01:05 -07:00
printk - Nick Piggin's "shoot lazy tlbs" series, to improve the peformance of 2023-04-27 19:42:02 -07:00
rcu RCU Changes for 6.4: 2023-04-24 12:16:14 -07:00
sched sched: fix cid_lock kernel-doc warnings 2023-05-08 10:58:28 +02:00
time tick/common: Align tick period during sched_timer setup 2023-06-16 20:45:28 +02:00
trace Tracing fixes for 6.4: 2023-06-20 15:01:08 -07:00
.gitignore
acct.c
async.c
audit_fsnotify.c
audit_tree.c
audit_watch.c
audit.c
audit.h
auditfilter.c
auditsc.c
backtracetest.c
bounds.c
capability.c
cfi.c
compat.c sched_getaffinity: don't assume 'cpumask_size()' is fully initialized 2023-03-14 19:32:38 -07:00
configs.c
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cpu_pm.c
cpu.c - Nick Piggin's "shoot lazy tlbs" series, to improve the peformance of 2023-04-27 19:42:02 -07:00
crash_core.c mm, treewide: redefine MAX_ORDER sanely 2023-04-05 19:42:46 -07:00
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delayacct.c delayacct: track delays from IRQ/SOFTIRQ 2023-04-18 16:39:34 -07:00
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exit.c fork, vhost: Use CLONE_THREAD to fix freezer/ps regression 2023-06-01 17:15:33 -04:00
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hung_task.c kernel/hung_task.c: set some hung_task.c variables storage-class-specifier to static 2023-04-08 13:45:37 -07:00
iomem.c
irq_work.c trace: Add trace_ipi_send_cpu() 2023-03-24 11:01:29 +01:00
jump_label.c
kallsyms_internal.h
kallsyms_selftest.c kallsyms: Delete an unused parameter related to {module_}kallsyms_on_each_symbol() 2023-03-19 13:27:19 -07:00
kallsyms_selftest.h
kallsyms.c kallsyms: Delete an unused parameter related to {module_}kallsyms_on_each_symbol() 2023-03-19 13:27:19 -07:00
kcmp.c
Kconfig.freezer
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kexec_file.c kexec: support purgatories with .text.hot sections 2023-06-12 11:31:50 -07:00
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kheaders.c kheaders: Use array declaration instead of char 2023-03-24 20:10:59 -07:00
kprobes.c
ksysfs.c kernel/ksysfs.c: use sysfs_emit for sysfs show handlers 2023-03-24 17:09:14 +01:00
kthread.c - Nick Piggin's "shoot lazy tlbs" series, to improve the peformance of 2023-04-27 19:42:02 -07:00
latencytop.c
Makefile modules-6.4-rc1 2023-04-27 16:36:55 -07:00
module_signature.c
notifier.c notifiers: add tracepoints to the notifiers infrastructure 2023-04-08 13:45:38 -07:00
nsproxy.c convert setns(2) to fdget()/fdput() 2023-04-20 22:55:35 -04:00
padata.c padata: use alignment when calculating the number of worker threads 2023-03-14 17:06:44 +08:00
panic.c cpu: Mark nmi_panic_self_stop() __noreturn 2023-04-14 17:31:26 +02:00
params.c module: make module_ktype structure constant 2023-03-09 12:55:15 -08:00
pid_namespace.c kernel: pid_namespace: simplify sysctls with register_sysctl() 2023-05-02 19:23:29 -07:00
pid_sysctl.h kernel: pid_namespace: simplify sysctls with register_sysctl() 2023-05-02 19:23:29 -07:00
pid.c pid: add pidfd_prepare() 2023-04-03 11:16:56 +02:00
profile.c
ptrace.c ptrace: Provide set/get interface for syscall user dispatch 2023-04-16 14:23:07 +02:00
range.c
reboot.c
regset.c
relay.c relayfs: fix out-of-bounds access in relay_file_read 2023-05-02 17:23:27 -07:00
resource_kunit.c
resource.c
rseq.c
scftorture.c
scs.c
seccomp.c seccomp: simplify sysctls with register_sysctl_init() 2023-04-13 11:49:20 -07:00
signal.c fork, vhost: Use CLONE_THREAD to fix freezer/ps regression 2023-06-01 17:15:33 -04:00
smp.c trace,smp: Trace all smp_function_call*() invocations 2023-03-24 11:01:30 +01:00
smpboot.c
smpboot.h
softirq.c softirq: Add trace points for tasklet entry/exit 2023-04-15 10:17:16 +02:00
stackleak.c stackleak: allow to specify arch specific stackleak poison function 2023-04-20 11:36:35 +02:00
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static_call_inline.c
static_call.c
stop_machine.c
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sys.c mm/ksm: unmerge and clear VM_MERGEABLE when setting PR_SET_MEMORY_MERGE=0 2023-05-02 17:21:49 -07:00
sysctl-test.c
sysctl.c mm: compaction: move compaction sysctl to its own file 2023-04-13 11:49:35 -07:00
task_work.c
taskstats.c
torture.c
tracepoint.c
tsacct.c
ucount.c
uid16.c
uid16.h
umh.c
up.c
user_namespace.c
user-return-notifier.c
user.c
usermode_driver.c
utsname_sysctl.c utsname: simplify one-level sysctl registration for uts_kern_table 2023-04-13 11:49:35 -07:00
utsname.c
vhost_task.c vhost: Fix worker hangs due to missed wake up calls 2023-06-08 15:43:09 -04:00
watch_queue.c modules-6.4-rc1 2023-04-27 16:36:55 -07:00
watchdog_hld.c
watchdog.c
workqueue_internal.h
workqueue.c workqueue: clean up WORK_* constant types, clarify masking 2023-06-23 12:08:14 -07:00