kernel/git/next/linux-next.git/tools/sched_ext, branch master

Merge branch 'for-next' of https://git.kernel.org/pub/scm/linux/kernel/git/tj/sched_ext.git

2026-09-04T17:51:27+00:00

mm: replace PF_KCOMPACTD flag with kthread_func() check

2026-09-04T00:39:12+00:00

PF_KCOMPACTD was introduced by commit ce6d9c1c2b5c ("NFS: fix nfs_release_folio() to not deadlock via kcompactd writeback") so nfs_release_folio() could detect kcompactd context and skip writeback. The flag is only consumed by current_is_kcompactd(), whose sole caller is nfs_release_folio(). Replace the flag-based check with kthread_func(current) == kcompactd, freeing the 0x00010000 PF flag bit. Link: https://lore.kernel.org/20260902131653.1338227-5-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang Acked-by: Shakeel Butt Acked-by: Zi Yan Acked-by: Vlastimil Babka (SUSE) Cc: Brendan Jackman Cc: Carlos Maiolino Cc: Christian Brauner Cc: Christoph Hellwig Cc: "Darrick J. Wong" Cc: David Hildenbrand Cc: Johannes Weiner Cc: Lorenzo Stoakes Cc: Michal Hocko Cc: Suren Baghdasaryan Signed-off-by: Andrew Morton

mm: replace PF_KSWAPD flag with kthread_func() check

2026-09-04T00:39:11+00:00

The preceding commits removed the last consumer that propagated PF_KSWAPD beyond kswapd itself (XFS btree split worker inheritance). The only remaining setter of PF_KSWAPD is kswapd(), and every current_is_kswapd() caller only needs to check whether the current task *is* the kswapd thread, not whether it inherited the flag. Replace the flag-based test with kthread_func(current) == kswapd, freeing the 0x00020000 PF flag bit. Link: https://lore.kernel.org/20260902131653.1338227-4-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang Acked-by: Shakeel Butt Acked-by: Vlastimil Babka (SUSE) Acked-by: Zi Yan Cc: Brendan Jackman Cc: Carlos Maiolino Cc: Christian Brauner Cc: Christoph Hellwig Cc: "Darrick J. Wong" Cc: David Hildenbrand Cc: Johannes Weiner Cc: Lorenzo Stoakes Cc: Michal Hocko Cc: Suren Baghdasaryan Signed-off-by: Andrew Morton

sched_ext/scx_flatcg: Make cgv_node_less() wraparound-safe

2026-09-02T06:35:23+00:00

cgv_node_less() compares cvtimes with a plain <, which misorders once cvtime wraps: the wrapped node lands at the front of the tree while the unwrapped ones get stuck behind it. Each CPU picking a cgroup charges it a full slice, making wrap occur earlier than a naive estimate might suggest. Use time_before() instead. cgrp_cap_budget() bounds the lag behind cvtime_now, while the lead is bounded by the slice charge plus pending cvtime_delta on re-insertion, so the cyclic ordering assumptions of time_before() hold. Fixes: a4103eacc2ab ("sched_ext: Add a cgroup scheduler which uses flattened hierarchy") Reported-by: Sashiko Link: https://lore.kernel.org/r/3f1ce004-e259-4e72-a5f7-14a5050053bd@linux.dev Signed-off-by: Tao Cui Signed-off-by: Tejun Heo

sched_ext: Check bpf_timer_start return values in scx_qmap

2026-08-31T16:47:39+00:00

monitor_timerfn(), lowpri_timerfn() and round_robin_timerfn() ignore bpf_timer_start()'s return value: a failed re-arm silently stops the periodic heartbeat, starving every task parked in LOWPRI_DSQ (lowpri) or freezing cid rotation (round-robin). Check the returns and raise scx_bpf_error(), matching the init paths. Signed-off-by: Wanwu Li Signed-off-by: Tejun Heo

sched_ext: Fix vtime delta loss in scx_flatcg cgroup migration

2026-08-31T16:47:33+00:00

fcg_cgroup_move() lost the signed vtime offset across cgroup migration in the mechanical conversion to time helpers: time_delta() clamps negative deltas to 0, so a queued task (whose dsq_vtime is normally behind the source frontier) loses its accumulated vtime credit and lands exactly at the destination frontier instead of keeping its relative position. Restore the wrapping signed subtraction. Fixes: 62addc6dbf36 ("sched_ext: Use time helpers in BPF schedulers") Signed-off-by: Wanwu Li Signed-off-by: Tejun Heo

sched_ext: Fix timer pinning and return value in scx_central

2026-08-31T16:47:26+00:00

central_timerfn() re-arms the timer with a hardcoded BPF_F_TIMER_CPU_PIN flag and ignores the return value, defeating start_central_timer()'s -EINVAL fallback for kernels without the flag (<6.7): on such kernels the first tick kills the timer permanently with no diagnostic. Honor timer_pinned and check the return like the initial arm does. Fixes: 22a920209ab6 ("sched_ext: Implement tickless support") Signed-off-by: Wanwu Li Signed-off-by: Tejun Heo

sched_ext: Sync common and compat headers from the scx repo

2026-08-22T07:19:26+00:00

Sync common.bpf.h, compat.bpf.h and compat.h with the scx repo, which accumulated the following: - __COMPAT_read_enum() can now recover 64-bit scx enum values from kernel BTF generated without BTF_KIND_ENUM64 support (pahole < 1.24 or --skip_encoding_btf_enum64, e.g. COS/GKE kernels), substituting values from the build-time vmlinux.h cross-checked against the low 32 bits the kernel does provide. - is_migration_disabled() no longer assumes the BPF prolog always disables migration. Since 8e4f0b1ebcf2 ("bpf: use rcu_read_lock_dont_migrate() for trampoline.c") the prolog only does so under CONFIG_PREEMPT_RCU, so the old current-task test under-reported on v6.18+ !PREEMPT_RCU kernels. A runtime probe on bpf_scx_reg() handles older kernels with backported trampoline behavior. - __COMPAT_scx_bpf_dsq_peek() is gated behind kernel v7.1 where 2f2ea7709266 ("sched_ext: Use dsq->first_task instead of list_empty() in dispatch_enqueue() FIFO-tail") fixed the kfunc spuriously returning NULL on non-empty FIFO DSQs, and the new scx_bpf_reenqueue_local_from_anywhere() provides a callable-from-anywhere reenqueue which prefers the generic scx_bpf_dsq_reenq(). Both were first posted by Gavin Guo and Changwoo Min and are picked up here with the review feedback folded in. - __COMPAT_scx_bpf_cpu_curr() and the scx_bpf_cpu_rq() declaration are restored. Schedulers built from these headers still run on pre-v6.18 kernels where scx_bpf_cpu_curr() does not resolve and the scx_bpf_cpu_rq() fallback still exists. - scx_clock_task() and scx_clock_pelt() document their stale-read behavior for remote idle CPUs under NO_HZ_IDLE. Link: https://lore.kernel.org/all/20260817143126.562923-1-changwoo@igalia.com Signed-off-by: Tejun Heo

sched_ext: Sync tools autogen enum headers from the scx repo

2026-08-22T07:19:26+00:00

Regenerate enum_defs.autogen.h against the current tree, picking up the dispatch verdict enums and dropping the marker for the removed SCX_RQ_IN_BALANCE. Add enums_abi.autogen.h, a table of 64-bit scx enumerator values generated from vmlinux.h, used as the substitution source when the running kernel's BTF truncates 64-bit enum values to 32 bits. Signed-off-by: Tejun Heo

sched_ext: Merge branch 'for-7.3-arena-args' into for-7.3

2026-08-17T21:20:34+00:00

Pull to receive the __arena argument conversion: 67f1f4a48c24 ("sched_ext: Pass kernel arena pointers to ops_cid callbacks") a8dc810968af ("sched_ext: Convert sub-cap kfuncs to __arena cmask arguments") a05c5b5cb5cf ("sched_ext: Convert scx_bpf_cid_override() to __arena array arguments") along with the bpf-next branch carrying the __arena argument support they depend on. Conflict in kernel/sched/ext/ext.c between: c384ab8a0b13 ("sched_ext: Move the config-off sub-cap kfunc stubs into sub.c") and: a8dc810968af ("sched_ext: Convert sub-cap kfuncs to __arena cmask arguments") which updated the stubs in their old ext.c location. Resolved by keeping ext.c without the stubs and applying the prototype conversion to the relocated stubs in sub.c. Signed-off-by: Tejun Heo