Commit graph

12 commits

Author SHA1 Message Date
Nicolas Pitre
46aa6717ff Revert "arch: deprecate _current"
Mostly a revert of commit b1def7145f ("arch: deprecate `_current`").

This commit was part of PR #80716 whose initial purpose was about providing
an architecture specific optimization for _current. The actual deprecation
was sneaked in later on without proper discussion.

The Zephyr core always used _current before and that was fine. It is quite
prevalent as well and the alternative is proving rather verbose.
Furthermore, as a concept, the "current thread" is not something that is
necessarily architecture specific. Therefore the primary abstraction
should not carry the arch_ prefix.

Hence this revert.

Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
2025-01-10 07:49:08 +01:00
Peter Mitsis
85a9cffd0f kernel: cache priority queue index on UP multiq
Even though calculating the priority queue index in the priority
multiq is quick, caching it allows us to extract an extra 2% in
terms of performance as measured by the thread_metric cooperative
benchmark.

Signed-off-by: Peter Mitsis <peter.mitsis@intel.com>
2025-01-07 18:24:09 +01:00
Peter Mitsis
ea6adb6726 kernel: Add custom scheduler yield routines
Adds customized yield implementations based upon the selected
scheduler (dumb, multiq or scalable). Although each follows the
same broad outline, some of them allow for additional tweaking
to extract maximal performance. For example, the multiq variant
improves the performance of k_yield() by about 20%.

Signed-off-by: Peter Mitsis <peter.mitsis@intel.com>
2025-01-07 18:24:09 +01:00
Peter Mitsis
472c71d3f4 kernel: Add method to dequeue from a dlist
Dequeuing from a doubly linked list is similar to removing an item
except that it does not re-initialize the dequeued node.

This comes in handy when sorting a doubly linked list (where the
node gets removed and re-added). In that circumstance, re-initializing
the node is required. Furthermore, the compiler does not always
'understand' this. Thus, when performance is critical, dequeuing
may be preferred to removing.

Signed-off-by: Peter Mitsis <peter.mitsis@intel.com>
2025-01-07 18:24:09 +01:00
Peter Mitsis
d1c2fc0667 kernel: inline z_sched_prio_cmp()
Inlines z_sched_prio_cmp() to get better performance.

Signed-off-by: Peter Mitsis <peter.mitsis@intel.com>
2025-01-07 18:24:09 +01:00
Peter Mitsis
c6693bfdae kernel: Clean up priority_q.h
Minor cleanups include ...
 1. Eliminating unnecessary if-defs and forward declarations
 2. Co-locating routines of the same queue type

Signed-off-by: Peter Mitsis <peter.mitsis@intel.com>
2025-01-07 18:24:09 +01:00
Tom Burdick
2b5012a5d9 kernel: Move run queue initialization
Move the initialization of the priority q for running out of sched.c to
remove one more ifdef from sched.c. No change in functionality but
better matches the rest of sched.c and priority_q.h such that the
ifdefry needed is done in in priority_q.h.

Signed-off-by: Tom Burdick <thomas.burdick@intel.com>
2024-11-16 15:20:15 -05:00
frei tycho
d8179401b5 kernel: avoided increments/decrements with side effects
- moved ++/-- before or after the value use

Signed-off-by: frei tycho <tfrei@baumer.com>
2024-06-14 19:19:29 +02:00
Anas Nashif
4593f0d71c kernel: priority queues: declare as static inlines
After the move to C files we got some drop in the performance when
running latency_measure. This patch declares the priority queue
functions as static inlines with minor optimizations.

The result for one metric (on qemu):

3.6 and before the anything was changed:

  Get data from LIFO (w/ ctx switch): 13087 ns

after original change (46484da502):

  Get data from LIFO (w/ ctx switch): 13663 ns

with this change:

  Get data from LIFO (w/ ctx switch): 12543 ns

So overall, a net gain of ~ 500ns that can be seen across the board on many
of the metrics.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2024-04-22 16:40:11 -04:00
Simon Hein
bcd1d19322 kernel: add closing comments to config endifs
Add a closing comment to the endif with the configuration
information to which the endif belongs too.
To make the code more clearer if the configs need adaptions.

Signed-off-by: Simon Hein <Shein@baumer.com>
2024-03-25 18:03:31 -04:00
TaiJu Wu
1f5f0cf838 sched: Remove multi-level queue priority limit
Modified bitmask to  bitmask array, it can make multilevel queue remove
32 bit prioriry limit.

We can scan bitmask array to find which queue have ready thread.

Only need the number of queues as priority because the priority
is checked on create_thread.

Signed-off-by: TaiJu Wu <tjwu1217@gmail.com>
2024-03-12 19:37:40 -04:00
Anas Nashif
46484da502 kernel: move priority queue handling to own file/header
clean up headers under include/ and move handling of priority queue to
own file/header.
No need for the header  include/zephyr/kernel/internal/sched_priq.h
anymore. Move the relevant structures where they are being used in
kernel_structs.h.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2024-03-02 15:06:45 +01:00