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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-19 10:09:22 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-19 10:09:22 -0700 |
| commit | f4cdf7ca9a1fdcca413157df19753f388a5a224e (patch) | |
| tree | 60a31895b2446cd7fa27514e8c2843534a0de0da /lib/percpu_test.c | |
| download | linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.tar.gz linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.zip | |
Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab:
- v4l2-core: added ISP statistics support and per-block validation
- v4l2-core: Allow unknown HDR10 white point and luminance
- New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor
- New codec: Milos: VPU v2.0 codec support
- isp driver: gained support for Dreamchip RPPX1 ISP framework
- vsp1 driver: gained support for RZ/T2H and RZ/N2H
- Novalake driver: gained CVS support for new NVL hardware
- dvb-core: fix feed leak on failed DMX_ADD_PID
- several driver fixes, cleanups and minor improvements
* tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits)
media: ipu-bridge: check all DMI entries when overriding sensor rotation
media: v4l2-async: avoid deleting unlinked ASC entry on link error
media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement
media: intel/ipu6: fix async notifier cleanup leak on parse error
media: staging/ipu7: fix async notifier UAF on probe error path
media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path
media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem()
media: rcar-isp: Fix VSPX reference leaks
media: rcar-isp: Release ISPCORE resources
media: i2c: imx415: Release runtime PM reference on VBLANK error
media: i2c: imx415: Return test pattern write errors
media: renesas: vsp1: Declare index variables in for loop statement
media: renesas: vsp1: Make reset control optional to support platforms without a reset line
media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs
media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs
media: nxp: imx8-isi: Add additional 32-bit RGB format support
media: nxp: imx8-isi: Add 16-bit raw Bayer format support
media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams
media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks
media: nxp: imx8-isi: Correct color map between V4L2 and ISI
...
Diffstat (limited to 'lib/percpu_test.c')
| -rw-r--r-- | lib/percpu_test.c | 148 |
1 files changed, 148 insertions, 0 deletions
diff --git a/lib/percpu_test.c b/lib/percpu_test.c new file mode 100644 index 000000000..ce7124b16 --- /dev/null +++ b/lib/percpu_test.c @@ -0,0 +1,148 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include <linux/limits.h> +#include <linux/module.h> + +/* validate @native and @pcp counter values match @expected */ +#define CHECK(native, pcp, expected) \ + do { \ + WARN((native) != (expected), \ + "raw %ld (0x%lx) != expected %lld (0x%llx)", \ + (native), (native), \ + (long long)(expected), (long long)(expected)); \ + WARN(__this_cpu_read(pcp) != (expected), \ + "pcp %ld (0x%lx) != expected %lld (0x%llx)", \ + __this_cpu_read(pcp), __this_cpu_read(pcp), \ + (long long)(expected), (long long)(expected)); \ + } while (0) + +static DEFINE_PER_CPU(long, long_counter); +static DEFINE_PER_CPU(unsigned long, ulong_counter); + +static int __init percpu_test_init(void) +{ + /* + * volatile prevents compiler from optimizing it uses, otherwise the + * +ul_one/-ul_one below would replace with inc/dec instructions. + */ + volatile unsigned int ui_one = 1; + unsigned long long ull = 0; + unsigned long ul = 0; + long l = 0; + + pr_info("percpu test start\n"); + + preempt_disable(); + + l += -1; + __this_cpu_add(long_counter, -1); + CHECK(l, long_counter, -1); + + l += 1; + __this_cpu_add(long_counter, 1); + CHECK(l, long_counter, 0); + + ul = 0; + __this_cpu_write(ulong_counter, 0); + + ul += 1UL; + __this_cpu_add(ulong_counter, 1UL); + CHECK(ul, ulong_counter, 1); + + ul += -1UL; + __this_cpu_add(ulong_counter, -1UL); + CHECK(ul, ulong_counter, 0); + + ul += -(unsigned long)1; + __this_cpu_add(ulong_counter, -(unsigned long)1); + CHECK(ul, ulong_counter, -1); + + ul = 0; + __this_cpu_write(ulong_counter, 0); + + ul -= 1; + __this_cpu_dec(ulong_counter); + CHECK(ul, ulong_counter, -1); + CHECK(ul, ulong_counter, ULONG_MAX); + + l += -ui_one; + __this_cpu_add(long_counter, -ui_one); + CHECK(l, long_counter, 0xffffffff); + + l += ui_one; + __this_cpu_add(long_counter, ui_one); + CHECK(l, long_counter, (long)0x100000000LL); + + + l = 0; + __this_cpu_write(long_counter, 0); + + l -= ui_one; + __this_cpu_sub(long_counter, ui_one); + CHECK(l, long_counter, -1); + + l = 0; + __this_cpu_write(long_counter, 0); + + l += ui_one; + __this_cpu_add(long_counter, ui_one); + CHECK(l, long_counter, 1); + + l += -ui_one; + __this_cpu_add(long_counter, -ui_one); + CHECK(l, long_counter, (long)0x100000000LL); + + l = 0; + __this_cpu_write(long_counter, 0); + + l -= ui_one; + this_cpu_sub(long_counter, ui_one); + CHECK(l, long_counter, -1); + CHECK(l, long_counter, ULONG_MAX); + + ul = 0; + __this_cpu_write(ulong_counter, 0); + + ul += ui_one; + __this_cpu_add(ulong_counter, ui_one); + CHECK(ul, ulong_counter, 1); + + ul = 0; + __this_cpu_write(ulong_counter, 0); + + ul -= ui_one; + __this_cpu_sub(ulong_counter, ui_one); + CHECK(ul, ulong_counter, -1); + CHECK(ul, ulong_counter, ULONG_MAX); + + ul = ull = 0; + __this_cpu_write(ulong_counter, 0); + + ul = ull += UINT_MAX; + __this_cpu_add(ulong_counter, ull); + CHECK(ul, ulong_counter, UINT_MAX); + + ul = 3; + __this_cpu_write(ulong_counter, 3); + + ul = this_cpu_sub_return(ulong_counter, ui_one); + CHECK(ul, ulong_counter, 2); + + ul = __this_cpu_sub_return(ulong_counter, ui_one); + CHECK(ul, ulong_counter, 1); + + preempt_enable(); + + pr_info("percpu test done\n"); + return -EAGAIN; /* Fail will directly unload the module */ +} + +static void __exit percpu_test_exit(void) +{ +} + +module_init(percpu_test_init) +module_exit(percpu_test_exit) + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Greg Thelen"); +MODULE_DESCRIPTION("percpu operations test"); |
