When we request realtime priority from rtkit, we have a rttime limit. If we exceed
that limit, the kernel will send SIGKILL to the process to terminate it.
This isn't something that most high priority processes will want, only processes
that selectively opt into SCHED_RR/FIFO through SDL_HINT_THREAD_PRIORITY_POLICY
should be subject to this level of scrutiny.
This change:
* Switches non-apple posix OSs to use SCHED_OTHER instead of SCHED_RR
for SDL_THREAD_PRIORITY_HIGH/SDL_THREAD_PRIORITY_TIME_CRITICAL.
* Fixes using a hardcoded RLIMIT_RTTIME, instead queries it from rtkit
* Only sets RLIMIT_RTTIME for MakeRealtime rtkit requests
* Adds a note regarding the possible SIGKILL with SDL_HINT_THREAD_PRIORITY_POLICY
* Introduces SDL_HINT_THREAD_FORCE_REALTIME_TIME_CRITICAL to allow apps to acquire realtime scheduling policies on Linux
CPU Vendor ID "Shanghai" and "CentaurHauls" belongs to Zhaoxin.
Background:
Shanghai Zhaoxin Semiconductor Co., Ltd ("Zhaoxin") , established in 2013,
headquartered in Zhangjiang, Shanghai, China. Zhaoxin aims at providing
general-purpose x86 processors.
Related Zhaoxin Linux Kernel patch can be found at
https://lore.kernel.org/lkml/01042674b2f741b2aed1f797359bdffb@zhaoxin.com
Best regards.
Debugging inside rtkit showed we were failing the RLIMIT_RTTIME check, now that we're asking for realtime and not just high-priority due to a change in SDL.
Between that and the DBus code in SDL being wrong in previous changelist I'm not sure how this could have ever worked.
Nov 02 20:34:15 redcore rtkit-daemon[2825]: Failed to parse MakeThreadRealtime() method call: Argument 1 is specified to be of type "uint32", but is actually of type "int32"
Nov 02 20:34:15 redcore rtkit-daemon[2825]: Failed to parse MakeThreadRealtime() method call: Argument 1 is specified to be of type "uint32", but is actually of type "int32"
Docs:
http://git.0pointer.net/rtkit.git/tree/README
CLIENTS:
To be able to make use of realtime scheduling clients may
request so with a small D-Bus interface that is accessible on
the interface org.freedesktop.RealtimeKit1 as object
/org/freedesktop/RealtimeKit1 on the service
org.freedesktop.RealtimeKit1:
void MakeThreadRealtime(u64 thread_id, u32 priority);
void MakeThreadHighPriority(u64 thread_id, s32 priority);
wcodelyokoyt
The atom name that X11_GetAtomName() returns never gets freed, which result in a minor memory leak (14 bytes?) every time the user drops a file on a window.
You can see the line in question here:
6b6170caf6/src/video/x11/SDL_x11events.c (L1350)
Fix: call XFree on name after the while loop.
Joel Linn
This patch fixes a MSVC warning, which is dependent on the regional settings of the build system. Although the character is inside a comment and harmless, it is undesirable to disable the warning for this.
OpenGL leaves the final line segment open, SDL's software renderer does not,
so we need a tiny bit of trigonometry here to move one more pixel in the right
direction.
Xbox Elite controllers use AUX1-AUX4 to represent the paddle buttons when using the HIDAPI driver
PS4 and PS5 controllers use AUX1 to represent the touchpad button
Nintendo Switch Pro controllers use AUX1 to represent the capture button
This allows one to build Raspberry Pi versions on an ancient version of
Raspbian and get both the KMSDRM and RPI video targets built into SDL, giving
maximum binary compatibility from linking against an older glibc, etc, but
also making one library that can access video on all RPi models and OS
releases.
