linux/Documentation/core-api
Linus Torvalds d6b6d39054 workqueue: Changes for v6.13
- Maximum concurrency limit of 512 which was set a long time ago is too low
   now. A legitimate use (BPF cgroup release) of system_wq could saturate it
   under stress test conditions leading to false dependencies and deadlocks.
   While the offending use was switched to a dedicated workqueue, use the
   opportunity to bump WQ_MAX_ACTIVE four fold and document that system
   workqueue shouldn't be saturated. Workqueue should add at least a warning
   mechanism for cases where system workqueues are saturated.
 
 - Recent workqueue updates to support more flexible execution topology made
   unbound workqueues use per-cpu worker pool frontends which pushed up
   workqueue flush overhead. As consecutive CPUs are likely to be pointing to
   the same worker pool, reduce overhead by switching locks only when
   necessary.
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Merge tag 'wq-for-6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq

Pull workqueue updates from Tejun Heo:

 - The maximum concurrency limit of 512 which was set a long time ago is
   too low now.

   A legitimate use (BPF cgroup release) of system_wq could saturate it
   under stress test conditions leading to false dependencies and
   deadlocks.

   While the offending use was switched to a dedicated workqueue, use
   the opportunity to bump WQ_MAX_ACTIVE four fold and document that
   system workqueue shouldn't be saturated. Workqueue should add at
   least a warning mechanism for cases where system workqueues are
   saturated.

 - Recent workqueue updates to support more flexible execution topology
   made unbound workqueues use per-cpu worker pool frontends which
   pushed up workqueue flush overhead.

   As consecutive CPUs are likely to be pointing to the same worker
   pool, reduce overhead by switching locks only when necessary.

* tag 'wq-for-6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: Reduce expensive locks for unbound workqueue
  workqueue: Adjust WQ_MAX_ACTIVE from 512 to 2048
  workqueue: doc: Add a note saturating the system_wq is not permitted
2024-11-20 09:41:11 -08:00
..
irq
wrappers
asm-annotations.rst docs: move x86 documentation into Documentation/arch/ 2023-03-30 12:58:51 -06:00
assoc_array.rst
boot-time-mm.rst
cachetlb.rst mm: remove ARCH_IMPLEMENTS_FLUSH_DCACHE_FOLIO 2023-08-24 16:20:19 -07:00
circular-buffers.rst
cleanup.rst cleanup: Add usage and style documentation 2024-08-05 16:54:41 +02:00
cpu_hotplug.rst Documentation: core-api/cpuhotplug: Fix missing prefix 2024-10-07 11:50:54 -06:00
debug-objects.rst
debugging-via-ohci1394.rst Documentation: Drop or replace remaining mentions of IA64 2023-09-11 08:13:18 +00:00
dma-api-howto.rst docs: dma: correct dma_set_mask() sample code 2024-04-02 10:07:15 -06:00
dma-api.rst docs: dma-api: Fix description of the sync_sg API 2023-11-17 08:52:13 -07:00
dma-attributes.rst
dma-isa-lpc.rst
entry.rst Docs: typos/spelling 2024-05-02 10:02:29 -06:00
errseq.rst
floating-point.rst arch: add ARCH_HAS_KERNEL_FPU_SUPPORT 2024-05-19 14:36:17 -07:00
folio_queue.rst netfs: Add folio_queue API documentation 2024-09-30 14:10:51 +02:00
genalloc.rst
generic-radix-tree.rst
genericirq.rst Updates for the interrupt subsystem: 2024-07-22 13:52:05 -07:00
gfp_mask-from-fs-io.rst
idr.rst
index.rst Documentation: add missing folio_queue entry 2024-10-01 17:04:32 +02:00
kernel-api.rst Documentation: core-api: Drop :export: for int_log.h 2023-07-25 17:40:25 +01:00
kobject.rst
kref.rst
librs.rst
local_ops.rst
maple_tree.rst maple_tree: update the documentation of maple tree 2023-12-10 16:51:32 -08:00
memory-allocation.rst docs/core-api: memory-allocation: GFP_NOWAIT doesn't need __GFP_NOWARN 2024-07-29 15:10:25 -06:00
memory-hotplug.rst
mm-api.rst mm/slab, docs: switch mm-api docs generation from slab.c to slub.c 2023-12-05 11:11:34 +01:00
netlink.rst doc/netlink: Update genetlink-legacy documentation 2023-08-27 17:17:09 -07:00
packing.rst Documentation: core-api: packing: correct spelling 2023-02-15 21:40:54 -08:00
padata.rst Documentation: core-api: padata: correct spelling 2023-02-16 16:58:01 -07:00
pin_user_pages.rst mm: remove page_mkclean() 2024-07-03 19:30:17 -07:00
printk-basics.rst
printk-formats.rst printf: remove %pGt support 2024-09-03 21:15:42 -07:00
printk-index.rst docs:core-api: fixed typos and grammar in printk-index page 2024-05-07 08:01:11 -06:00
protection-keys.rst Documentation/protection-keys: add AArch64 to documentation 2024-10-14 17:27:48 +01:00
rbtree.rst
refcount-vs-atomic.rst
swiotlb.rst docs/core-api: swiotlb: fix typos 2024-10-17 09:37:05 -06:00
symbol-namespaces.rst
this_cpu_ops.rst arch: Remove cmpxchg_double 2023-06-05 09:36:39 +02:00
timekeeping.rst
tracepoint.rst
unaligned-memory-access.rst move asm/unaligned.h to linux/unaligned.h 2024-10-02 17:23:23 -04:00
union_find.rst Documentation: Fix the compilation errors in union_find.rst 2024-08-02 08:58:16 -10:00
watch_queue.rst
workqueue.rst workqueue: Adjust WQ_MAX_ACTIVE from 512 to 2048 2024-10-08 08:46:54 -10:00
xarray.rst