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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
commitf4cdf7ca9a1fdcca413157df19753f388a5a224e (patch)
tree60a31895b2446cd7fa27514e8c2843534a0de0da /tools/perf/bench/futex.c
downloadlinux-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 'tools/perf/bench/futex.c')
-rw-r--r--tools/perf/bench/futex.c64
1 files changed, 64 insertions, 0 deletions
diff --git a/tools/perf/bench/futex.c b/tools/perf/bench/futex.c
new file mode 100644
index 000000000..1968c9d00
--- /dev/null
+++ b/tools/perf/bench/futex.c
@@ -0,0 +1,64 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <err.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/prctl.h>
+
+#include "futex.h"
+
+#ifndef PR_FUTEX_HASH
+#define PR_FUTEX_HASH 78
+# define PR_FUTEX_HASH_SET_SLOTS 1
+# define PR_FUTEX_HASH_GET_SLOTS 2
+#endif // PR_FUTEX_HASH
+
+void futex_set_nbuckets_param(struct bench_futex_parameters *params)
+{
+ int ret;
+
+ if (params->nbuckets < 0)
+ return;
+
+ ret = prctl(PR_FUTEX_HASH, PR_FUTEX_HASH_SET_SLOTS, params->nbuckets, 0);
+ if (ret) {
+ printf("Requesting %d hash buckets failed: %d/%m\n",
+ params->nbuckets, ret);
+ err(EXIT_FAILURE, "prctl(PR_FUTEX_HASH)");
+ }
+}
+
+void futex_print_nbuckets(struct bench_futex_parameters *params)
+{
+ char *futex_hash_mode;
+ int ret;
+
+ ret = prctl(PR_FUTEX_HASH, PR_FUTEX_HASH_GET_SLOTS);
+ if (params->nbuckets >= 0) {
+ if (ret != params->nbuckets) {
+ if (ret < 0) {
+ printf("Can't query number of buckets: %m\n");
+ err(EXIT_FAILURE, "prctl(PR_FUTEX_HASH)");
+ }
+ printf("Requested number of hash buckets does not currently used.\n");
+ printf("Requested: %d in usage: %d\n", params->nbuckets, ret);
+ err(EXIT_FAILURE, "prctl(PR_FUTEX_HASH)");
+ }
+ if (params->nbuckets == 0)
+ ret = asprintf(&futex_hash_mode, "Futex hashing: global hash");
+ else
+ ret = asprintf(&futex_hash_mode, "Futex hashing: %d hash buckets",
+ params->nbuckets);
+ } else {
+ if (ret <= 0) {
+ ret = asprintf(&futex_hash_mode, "Futex hashing: global hash");
+ } else {
+ ret = asprintf(&futex_hash_mode, "Futex hashing: auto resized to %d buckets",
+ ret);
+ }
+ }
+ if (ret < 0)
+ err(EXIT_FAILURE, "ENOMEM, futex_hash_mode");
+ printf("%s\n", futex_hash_mode);
+ free(futex_hash_mode);
+}