diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst index 7c2a8ed80071..541b2604d211 100644 --- a/Documentation/admin-guide/cgroup-v2.rst +++ b/Documentation/admin-guide/cgroup-v2.rst @@ -1130,9 +1130,9 @@ policy and the underlying scheduler. From the point of view of the cpu controlle processes can be categorized as follows: * Processes under the fair-class scheduler -* Processes under a BPF scheduler with the ``cgroup_set_weight`` callback +* Processes under a BPF scheduler with the corresponding ``cgroup_set_*`` callback * Everything else: ``SCHED_{FIFO,RR,DEADLINE}`` and processes under a BPF scheduler - without the ``cgroup_set_weight`` callback + without the corresponding ``cgroup_set_*`` callback For details on when a process is under the fair-class scheduler or a BPF scheduler, check out :ref:`Documentation/scheduler/sched-ext.rst `. @@ -1223,7 +1223,9 @@ will be referred to. All time durations are in microseconds. $PERIOD duration. "max" for $MAX indicates no limit. If only one number is written, $MAX is updated. - This file affects only processes under the fair-class scheduler. + This file affects only processes under the fair-class scheduler and a BPF + scheduler with the ``cgroup_set_bandwidth`` callback depending on what + the callback actually does. cpu.max.burst A read-write single value file which exists on non-root @@ -1231,7 +1233,9 @@ will be referred to. All time durations are in microseconds. The burst in the range [0, $MAX]. - This file affects only processes under the fair-class scheduler. + This file affects only processes under the fair-class scheduler and a BPF + scheduler with the ``cgroup_set_bandwidth`` callback depending on what + the callback actually does. cpu.pressure A read-write nested-keyed file. @@ -1283,7 +1287,9 @@ will be referred to. All time durations are in microseconds. own relative priorities, but the cgroup itself will be treated as very low priority relative to its peers. - This file affects only processes under the fair-class scheduler. + This file affects only processes under the fair-class scheduler and a BPF + scheduler with the ``cgroup_set_idle`` callback depending on what the + callback actually does. Memory ------ diff --git a/Documentation/scheduler/sched-ext.rst b/Documentation/scheduler/sched-ext.rst index 0e97fd019994..794ae80b3ba3 100644 --- a/Documentation/scheduler/sched-ext.rst +++ b/Documentation/scheduler/sched-ext.rst @@ -230,7 +230,7 @@ optional. The following modified excerpt is from void BPF_STRUCT_OPS(simple_exit, struct scx_exit_info *ei) { - exit_type = ei->type; + exit_type = ei->kind; } SEC(".struct_ops") @@ -242,6 +242,21 @@ optional. The following modified excerpt is from .name = "simple", }; +Scheduler-Dependent Knobs +------------------------- + +The fair-class scheduler enforces CPU controller settings such as +``cpu.max``, ``cpu.weight`` and ``cpu.idle``. For sched_ext tasks, the +scheduler core communicates these settings to the BPF scheduler +through ``ops.cgroup_init()`` and reports subsequent changes through +the corresponding ``ops.cgroup_set_*()`` callbacks. Similarly, per-task +nice changes are converted to weights and reported through +``ops.set_weight()``. + +Each BPF scheduler is responsible for implementing the scheduling +semantics of these settings and may choose to ignore them. Consult the +loaded scheduler's documentation before relying on these controls. + Dispatch Queues --------------- diff --git a/kernel/sched/ext/ext.c b/kernel/sched/ext/ext.c index 10af28a9f2c0..713aa26b2828 100644 --- a/kernel/sched/ext/ext.c +++ b/kernel/sched/ext/ext.c @@ -876,9 +876,9 @@ struct task_struct *scx_task_iter_next_locked(struct scx_task_iter *iter) * unloading. The init_tasks ("swappers") should be excluded * from the iteration because: * - * - It's unsafe to use __setschduler_prio() on an init_task to - * determine the sched_class to use as it won't preserve its - * idle_sched_class. + * - It's unsafe to use __setscheduler_class() on an init_task + * to determine the sched_class to use as it won't preserve + * its idle_sched_class. * * - ops.init/exit_task() can easily be confused if called with * init_tasks as they, e.g., share PID 0. @@ -2806,6 +2806,8 @@ static void dispatch_to_local_dsq(struct scx_sched *sch, struct rq *rq, * @p: task to finish dispatching * @qseq_at_dispatch: qseq when @p started getting dispatched * @dsq_id: destination DSQ ID + * @slice: slice carried by the insert verdict, 0 keeps the current value + * @vtime: vtime carried by the insert verdict, committed on PRIQ inserts * @enq_flags: %SCX_ENQ_* * * Dispatching to local DSQs may need to wait for queueing to complete or @@ -5514,7 +5516,7 @@ static const struct kset_uevent_ops scx_uevent_ops = { }; /* - * Used by sched_fork() and __setscheduler_prio() to pick the matching + * Used by sched_fork() and __setscheduler_class() to pick the matching * sched_class. dl/rt are already handled. */ bool task_should_scx(int policy) @@ -7694,7 +7696,7 @@ static void scx_root_enable_workfn(struct kthread_work *work) /* * Enable ops for every task. Fork is excluded by scx_fork_rwsem * preventing new tasks from being added. No need to exclude tasks - * leaving as sched_ext_free() can handle both prepped and enabled + * leaving as sched_ext_dead() can handle both prepped and enabled * tasks. Prep all tasks first and then enable them with preemption * disabled. * @@ -7786,7 +7788,7 @@ static void scx_root_enable_workfn(struct kthread_work *work) /* * We're fully committed and can't fail. The task READY -> ENABLED - * transitions here are synchronized against sched_ext_free() through + * transitions here are synchronized against sched_ext_dead() through * scx_tasks_lock. */ percpu_down_write(&scx_fork_rwsem); @@ -8079,6 +8081,7 @@ static int bpf_scx_check_member(const struct btf_type *t, case offsetof(struct sched_ext_ops, cgroup_init): case offsetof(struct sched_ext_ops, cgroup_exit): case offsetof(struct sched_ext_ops, cgroup_prep_move): + case offsetof(struct sched_ext_ops, cgroup_set_bandwidth): #endif case offsetof(struct sched_ext_ops, cpu_online): case offsetof(struct sched_ext_ops, cpu_offline): @@ -9003,12 +9006,6 @@ static bool scx_dsq_move(struct bpf_iter_scx_dsq_kern *kit, if (unlikely(READ_ONCE(sch->aborting))) return false; - if (unlikely(!scx_task_on_sched(sch, p))) { - scx_error(sch, "scx_bpf_dsq_move[_vtime]() on %s[%d] but the task belongs to a different scheduler", - p->comm, p->pid); - return false; - } - /* * Can be called from either ops.dispatch() holding the dispatched rq's * lock or any context where no rq lock is held. If latter, lock @p's @@ -9040,6 +9037,17 @@ static bool scx_dsq_move(struct bpf_iter_scx_dsq_kern *kit, goto out; } + /* + * @p has been on $src_dsq and can't move anymore. If @p is not on @sch, + * the caller didn't have authority over @p at the time of the call. + */ + if (unlikely(!scx_task_on_sched(sch, p))) { + scx_error(sch, "scx_bpf_dsq_move[_vtime]() on %s[%d] but the task belongs to a different scheduler", + p->comm, p->pid); + raw_spin_unlock(&src_dsq->lock); + goto out; + } + /* @p is still on $src_dsq and stable, determine the destination */ dst_dsq = find_dsq_for_dispatch(sch, locked_rq ?: this_rq(), dsq_id, task_cpu(p)); @@ -9765,7 +9773,7 @@ __bpf_kfunc struct task_struct *bpf_iter_scx_dsq_next(struct bpf_iter_scx_dsq *i * bpf_iter_scx_dsq_destroy - Destroy a DSQ iterator * @it: iterator to destroy * - * Undo scx_iter_scx_dsq_new(). + * Undo bpf_iter_scx_dsq_new(). */ __bpf_kfunc void bpf_iter_scx_dsq_destroy(struct bpf_iter_scx_dsq *it) { @@ -11041,3 +11049,16 @@ static int __init scx_init(void) return 0; } __initcall(scx_init); + +/* + * Compatibility markers for userspace. Existence of a marker function + * represents that the kernel supports that sched-ext feature. + */ + +/* + * scx_compat_marker_cgroup_set_bandwidth_may_sleep: advertises that + * ops.cgroup_set_bandwidth() may be implemented as a sleepable callback. + */ +#ifdef CONFIG_EXT_GROUP_SCHED +DEFINE_SCX_COMPAT_MARKER(cgroup_set_bandwidth_may_sleep); +#endif /* CONFIG_EXT_GROUP_SCHED */ diff --git a/kernel/sched/ext/internal.h b/kernel/sched/ext/internal.h index 27bbf5e04d90..0967b99a4948 100644 --- a/kernel/sched/ext/internal.h +++ b/kernel/sched/ext/internal.h @@ -442,7 +442,7 @@ struct sched_ext_ops { * * Note that this callback may be called from a CPU other than the * one the task is going to run on. This can happen when a task - * property is changed (i.e., affinity), since scx_next_task_scx(), + * property is changed (i.e., affinity), since set_next_task_scx(), * which triggers this callback, may run on a CPU different from * the task's assigned CPU. * @@ -753,7 +753,7 @@ struct sched_ext_ops { * @burst_us: bandwidth control burst * * Update @cgrp's bandwidth control parameters. This is from the cpu.max - * cgroup interface. + * cgroup interface. This operation may block. * * @quota_us / @period_us determines the CPU bandwidth @cgrp is entitled * to. For example, if @period_us is 1_000_000 and @quota_us is @@ -2001,6 +2001,27 @@ struct scx_bstr_buf { char line[SCX_EXIT_MSG_LEN]; }; +/* Internal helper for DEFINE_SCX_COMPAT_MARKER(). */ +#define DECLARE_SCX_COMPAT_MARKER(func) \ + extern void scx_compat_marker_##func(void) + +/** + * DEFINE_SCX_COMPAT_MARKER() - define a userspace capability marker + * @func: marker suffix; the defined symbol is scx_compat_marker_@func + * + * Emit an empty, callerless function that is retained in the kernel's BTF. + * Its presence is part of the kernel<->userspace contract: userspace probes + * scx_compat_marker_@func (e.g. via BTF) to detect that this kernel supports + * the corresponding feature. + * + * The leading declaration suppresses the missing-prototype warning; the + * trailing declaration consumes the semicolon at the use site. + */ +#define DEFINE_SCX_COMPAT_MARKER(func) \ + DECLARE_SCX_COMPAT_MARKER(func); \ + __used __retain void scx_compat_marker_##func(void) {} \ + DECLARE_SCX_COMPAT_MARKER(func) + extern struct scx_sched __rcu *scx_root; DECLARE_PER_CPU(struct rq *, scx_locked_rq_state); diff --git a/tools/sched_ext/include/scx/common.bpf.h b/tools/sched_ext/include/scx/common.bpf.h index 979d4cabfaf9..76f5e025e107 100644 --- a/tools/sched_ext/include/scx/common.bpf.h +++ b/tools/sched_ext/include/scx/common.bpf.h @@ -48,6 +48,7 @@ extern int LINUX_KERNEL_VERSION __kconfig; extern const char CONFIG_CC_VERSION_TEXT[64] __kconfig __weak; extern const char CONFIG_LOCALVERSION[64] __kconfig __weak; +extern bool CONFIG_PREEMPT_RCU __kconfig __weak; /* * Earlier versions of clang/pahole lost upper 32bits in 64bit enums which can @@ -97,6 +98,7 @@ s32 scx_bpf_pick_any_cpu_node(const cpumask_t *cpus_allowed, int node, u64 flags s32 scx_bpf_pick_any_cpu(const cpumask_t *cpus_allowed, u64 flags) __ksym; bool scx_bpf_task_running(const struct task_struct *p) __ksym; s32 scx_bpf_task_cpu(const struct task_struct *p) __ksym; +struct rq *scx_bpf_cpu_rq(s32 cpu) __ksym __weak; struct rq *scx_bpf_locked_rq(void) __ksym; struct task_struct *scx_bpf_cpu_curr(s32 cpu) __ksym __weak; struct task_struct *scx_bpf_tid_to_task(u64 tid) __ksym __weak; @@ -527,32 +529,103 @@ static __always_inline const struct cpumask *cast_mask(struct bpf_cpumask *mask) return (const struct cpumask *)mask; } +/* + * True if the non-sleepable BPF trampoline prolog (__bpf_prog_enter) calls + * migrate_disable() for the current task. Recorded once by + * scx_lib_init_probe, an fentry program on bpf_scx_reg() that fires during + * the natural scheduler-attach call chain (auto-attached by scx_ops_attach!). + * + * Defaults to true (conservative). Over-reporting in is_migration_disabled() + * causes local-only dispatch, which is safe. Under-reporting can crash the + * scheduler, so we err high if the probe somehow fails to run. + */ +bool __scx_prolog_disables_migration __weak = true; + +/* + * scx_lib_init_probe - non-sleepable prolog probe. + * + * Attached to bpf_scx_reg(), the .reg callback in bpf_sched_ext_ops + * (kernel/sched/ext.c). The kernel's struct_ops machinery invokes + * bpf_scx_reg when userspace creates the scheduler link, before + * ops.init() fires. Its address is taken in the vtable, so the symbol + * is non-inlinable and has been stable since introduction. + * + * Entering via fentry runs us through __bpf_prog_enter -- the + * non-sleepable prolog that consumers of is_migration_disabled() live + * under. + * + * Loud warning: the prolog adds at most 1 to migration_disabled. + * Reading > 1 means something upstream in the + * bpf_struct_ops_link_create -> bpf_scx_reg path disabled migration + * before the prolog ran, invalidating the probe; audit and adjust. + */ +SEC("fentry/bpf_scx_reg") __weak +int scx_lib_init_probe(void *ctx) +{ + if (bpf_core_field_exists(((struct task_struct *)0)->migration_disabled)) { + const struct task_struct *p = bpf_get_current_task_btf(); + unsigned int md = p->migration_disabled; + + if (md > 1) + bpf_printk("scx_lib_init_probe: unexpected migration_disabled=%u " + "upstream of BPF prolog; probe result unreliable", + md); + + __scx_prolog_disables_migration = md > 0; + } + return 0; +} + /* * Return true if task @p cannot migrate to a different CPU, false * otherwise. + * + * IMPORTANT: designed for NON-SLEEPABLE BPF contexts only. Sleepable + * contexts (BPF_STRUCT_OPS_SLEEPABLE, SEC("syscall"), + * SEC("fentry.s/...")) enter via __bpf_prog_enter_sleepable() or + * __bpf_prog_enter_sleepable_recur(), both of which unconditionally + * call migrate_disable(); this helper can yield a false negative for + * p == current there, which can crash the scheduler. */ static inline bool is_migration_disabled(const struct task_struct *p) { /* - * Testing p->migration_disabled in a BPF code is tricky because the - * migration is _always_ disabled while running the BPF code. - * The prolog (__bpf_prog_enter) and epilog (__bpf_prog_exit) for BPF - * code execution disable and re-enable the migration of the current - * task, respectively. So, the _current_ task of the sched_ext ops is - * always migration-disabled. Moreover, p->migration_disabled could be - * two or greater when a sched_ext ops BPF code (e.g., ops.tick) is - * executed in the middle of the other BPF code execution. + * Testing p->migration_disabled in BPF is tricky because the BPF prolog + * (__bpf_prog_enter) may call migrate_disable() for the current task, + * making migration_disabled == 1 even for tasks that are not truly + * migration-disabled. * - * Therefore, we should decide that the _current_ task is - * migration-disabled only when its migration_disabled count is greater - * than one. In other words, when p->migration_disabled == 1, there is - * an ambiguity, so we should check if @p is the current task or not. + * Since commit 8e4f0b1ebcf2 ("bpf: use rcu_read_lock_dont_migrate() for + * trampoline.c"), the BPF prolog calls migrate_disable() only when + * CONFIG_PREEMPT_RCU is enabled. Two fast paths cover the common cases: + * + * 1) CONFIG_PREEMPT_RCU: prolog always calls migrate_disable(), so + * migration_disabled == 1 for the current task is ambiguous. + * Disambiguate by checking p == current. + * + * 2) v6.18+ without CONFIG_PREEMPT_RCU: prolog never calls + * migrate_disable(), so migration_disabled == 1 is unambiguously + * a real migrate_disable() call. + * + * A slow path handles pre-v6.18 kernels without CONFIG_PREEMPT_RCU, + * where the prolog historically called migrate_disable() unconditionally + * but a cherry-picked downstream kernel may not. The runtime-probed flag + * __scx_prolog_disables_migration (set by scx_lib_init_probe) distinguishes + * the two cases without relying on the kernel version alone. */ if (bpf_core_field_exists(p->migration_disabled)) { - if (p->migration_disabled == 1) - return bpf_get_current_task_btf() != p; - else - return p->migration_disabled; + if (p->migration_disabled == 1) { + /* Fast path: prolog always disables migration */ + if (CONFIG_PREEMPT_RCU) + return bpf_get_current_task_btf() != p; + /* Fast path: prolog never disables migration */ + if (LINUX_KERNEL_VERSION >= KERNEL_VERSION(6, 18, 0)) + return true; + /* Slow path: pre-v6.18, !PREEMPT_RCU - use runtime flag */ + return __scx_prolog_disables_migration ? + bpf_get_current_task_btf() != p : true; + } + return p->migration_disabled; } return false; } @@ -1021,7 +1094,20 @@ static inline u64 scx_clock_task(u32 cpu) { struct rq___local *rq = get_current_rq(cpu); - /* Equivalent to the kernel's rq_clock_task(). */ + /* + * Equivalent to the kernel's rq_clock_task(): wall-clock time minus + * cumulative IRQ time (CONFIG_IRQ_TIME_ACCOUNTING) and hypervisor + * steal time (CONFIG_PARAVIRT_TIME_ACCOUNTING). Without those configs, + * it equals rq->clock. + * + * Conceptually this clock advances during idle (the idle task counts + * as a running task), but rq->clock_task is only updated on scheduling + * events. With NO_HZ_IDLE (the default), the periodic tick is stopped + * on idle CPUs, so rq->clock_task is not refreshed while a CPU is + * idle. Reading this clock for a remote idle CPU from a BPF timer + * callback returns the value from when the CPU last went idle, making + * the delta over an idle interval effectively zero. + */ return rq ? rq->clock_task : 0; } @@ -1032,9 +1118,23 @@ static inline u64 scx_clock_pelt(u32 cpu) /* * Equivalent to the kernel's rq_clock_pelt(): subtracts * lost_idle_time from clock_pelt to absorb the jump that occurs - * when clock_pelt resyncs with clock_task at idle exit. The result - * is a continuous, capacity-invariant clock safe for both task - * execution time stamping and cross-idle measurements. + * when clock_pelt resyncs with clock_task at idle exit. The intent + * is a continuous, capacity- and frequency-invariant clock that is + * frozen during idle, IRQ, and hypervisor steal. + * + * However, like scx_clock_task(), this clock has a stale-read issue + * for remote idle CPUs with NO_HZ_IDLE (the default). clock_pelt + * itself advances at wall-clock rate (hardware-clock based), but + * lost_idle_time is only updated via update_rq_clock_pelt(), which + * requires update_rq_clock() to be called. With NO_HZ_IDLE, the + * periodic tick is stopped on idle CPUs, so lost_idle_time is not + * refreshed during idle. Reading this clock for a remote idle CPU + * from a BPF timer callback therefore returns a value that drifts + * at wall-clock rate -- the same stale behaviour as scx_clock_task(). + * + * Without NO_HZ_IDLE, periodic ticks keep lost_idle_time nearly in + * sync (stale by at most one tick period, ~1 ms), so the result is + * accurate. */ return rq ? (rq->clock_pelt - rq->lost_idle_time) : 0; } diff --git a/tools/sched_ext/include/scx/compat.bpf.h b/tools/sched_ext/include/scx/compat.bpf.h index 3ab642f92c8a..6944221f96cc 100644 --- a/tools/sched_ext/include/scx/compat.bpf.h +++ b/tools/sched_ext/include/scx/compat.bpf.h @@ -92,15 +92,20 @@ int bpf_cpumask_populate(struct bpf_cpumask *dst, void *src, size_t src__sz) __k /* * v6.19: Introduce lockless peek API for user DSQs. + * v7.1: Fix scx_bpf_dsq_peek() spuriously returning NULL on non-empty + * FIFO DSQs (2f2ea7709266). * - * Preserve the following macro until v6.21. + * The kfunc exists from v6.19 but can return NULL for a non-empty FIFO DSQ + * before the v7.1 fix. Require kernel version >= 7.1.0 before calling it; + * otherwise fall through to the bpf_iter_scx_dsq fallback below. */ static inline struct task_struct *__COMPAT_scx_bpf_dsq_peek(u64 dsq_id) { struct task_struct *p = NULL; struct bpf_iter_scx_dsq it; - if (bpf_ksym_exists(scx_bpf_dsq_peek)) + if (bpf_ksym_exists(scx_bpf_dsq_peek) && + LINUX_KERNEL_VERSION >= KERNEL_VERSION(7, 1, 0)) return scx_bpf_dsq_peek(dsq_id); if (!bpf_iter_scx_dsq_new(&it, dsq_id, 0)) p = bpf_iter_scx_dsq_next(&it); @@ -238,6 +243,26 @@ static inline bool __COMPAT_is_enq_cpu_selected(u64 enq_flags) scx_bpf_pick_any_cpu_node(cpus_allowed, node, flags) : \ scx_bpf_pick_any_cpu(cpus_allowed, flags)) +/* + * v6.18: Add a helper to retrieve the current task running on a CPU. + * + * The kernel tree dropped this helper and scx_bpf_cpu_rq(), but schedulers in + * this tree still support pre-v6.18 kernels where scx_bpf_cpu_curr() doesn't + * resolve and the scx_bpf_cpu_rq() fallback still exists. Keep it until + * pre-v6.18 kernels fall out of the support window. + */ +static inline struct task_struct *__COMPAT_scx_bpf_cpu_curr(int cpu) +{ + struct rq *rq; + + if (bpf_ksym_exists(scx_bpf_cpu_curr)) + return scx_bpf_cpu_curr(cpu); + + rq = scx_bpf_cpu_rq(cpu); + + return rq ? rq->curr : NULL; +} + /* * v6.19: To work around BPF maximum parameter limit, the following kfuncs are * replaced with variants that pack scalar arguments in a struct. Wrappers are @@ -378,6 +403,17 @@ static inline void scx_bpf_task_set_dsq_vtime(struct task_struct *p, u64 vtime) p->scx.dsq_vtime = vtime; } +/* + * v7.1: New scx_bpf_dsq_reenq() that allows re-enqueues on more DSQs. This + * will eventually deprecate scx_bpf_reenqueue_local(). + */ +void scx_bpf_dsq_reenq___compat(u64 dsq_id, u64 reenq_flags) __ksym __weak; + +static inline bool __COMPAT_has_generic_reenq(void) +{ + return bpf_ksym_exists(scx_bpf_dsq_reenq___compat); +} + /* * v6.19: The new void variant can be called from anywhere while the older v1 * variant can only be called from ops.cpu_release(). The double ___ prefixes on @@ -395,21 +431,31 @@ static inline bool __COMPAT_scx_bpf_reenqueue_local_from_anywhere(void) static inline void scx_bpf_reenqueue_local(void) { - if (__COMPAT_scx_bpf_reenqueue_local_from_anywhere()) + if (__COMPAT_has_generic_reenq()) + scx_bpf_dsq_reenq___compat(SCX_DSQ_LOCAL, 0); + else if (__COMPAT_scx_bpf_reenqueue_local_from_anywhere()) scx_bpf_reenqueue_local___v2___compat(); else scx_bpf_reenqueue_local___v1(); } -/* - * v7.1: New scx_bpf_dsq_reenq() that allows re-enqueues on more DSQs. This - * will eventually deprecate scx_bpf_reenqueue_local(). - */ -void scx_bpf_dsq_reenq___compat(u64 dsq_id, u64 reenq_flags) __ksym __weak; - -static inline bool __COMPAT_has_generic_reenq(void) +static inline int scx_bpf_reenqueue_local_from_anywhere(void) { - return bpf_ksym_exists(scx_bpf_dsq_reenq___compat); + /* + * The generic reenq kfunc and the v2 reenqueue-local variant can both be + * called from anywhere; v1 cannot. Test each ksym in its own branch with a + * distinct call: combining them with || would fold into a bitwise OR of the + * two ksym addresses, which the verifier rejects. + */ + if (__COMPAT_has_generic_reenq()) { + scx_bpf_dsq_reenq___compat(SCX_DSQ_LOCAL, 0); + return 0; + } + if (__COMPAT_scx_bpf_reenqueue_local_from_anywhere()) { + scx_bpf_reenqueue_local___v2___compat(); + return 0; + } + return -EOPNOTSUPP; } static inline void scx_bpf_dsq_reenq(u64 dsq_id, u64 reenq_flags) diff --git a/tools/sched_ext/include/scx/compat.h b/tools/sched_ext/include/scx/compat.h index d2e4384df5af..7c12df45fdba 100644 --- a/tools/sched_ext/include/scx/compat.h +++ b/tools/sched_ext/include/scx/compat.h @@ -10,9 +10,14 @@ #include #include #include +#include +#include #include +#include #include +#include "enums_abi.autogen.h" + struct btf *__COMPAT_vmlinux_btf __attribute__((weak)); static inline void __COMPAT_load_vmlinux_btf(void) @@ -23,6 +28,85 @@ static inline void __COMPAT_load_vmlinux_btf(void) } } +/* + * Recover the true value of a 64-bit enum enumerator whose kernel BTF entry + * was truncated to its low 32 bits. + * + * Kernels whose BTF was generated without BTF_KIND_ENUM64 support encode + * 64-bit enums as 8-byte BTF_KIND_ENUM entries whose enumerator values only + * carry the low 32 bits. This happens with pahole < 1.24, which predates + * ENUM64, and with pahole passing --skip_encoding_btf_enum64 (e.g. Google's + * Container-Optimized OS / GKE kernels deliberately pass it for backward + * compatibility with older BTF consumers). The high bits + * can't be recovered from kernel BTF, so substitute the value from the + * vmlinux.h this tree was built against, cross-checked against the low 32 + * bits the kernel did provide. + * + * Note that this is a best-effort recovery, not a ground truth. The + * substitution assumes the running kernel agrees with this tree's vmlinux.h + * on the high 32 bits, but only the low 32 bits can actually be verified. + * The cross-check is vacuous for enumerators whose value has no low bits + * set (e.g. SCX_DSQ_FLAG_BUILTIN, __SCX_ENQ_INTERNAL_MASK, + * SCX_ENQ_CLEAR_OPSS, SCX_ECODE_*): their lo32 is 0 and matches anything, + * so those substitutions rest entirely on the high bits never moving. An + * enumerator missing from the table (a kernel newer than this tree's + * vmlinux.h, or a stale autogen table) can't be recovered at all. If a + * substitution is ever wrong, the scheduler operates on bogus values (e.g. + * dispatching to nonexistent DSQ ids or silently dropping flags) and can + * wildly malfunction, which is why the mismatch and table-miss paths refuse + * instead of guessing. + */ +static inline bool __COMPAT_recover_truncated_enum64(const char *type, + const char *name, + u32 lo32, u64 *v) +{ + static bool warned; + size_t i; + + for (i = 0; i < sizeof(__scx_enum_abi_vals) / sizeof(__scx_enum_abi_vals[0]); i++) { + const struct __scx_enum_abi_val *e = &__scx_enum_abi_vals[i]; + + if (strcmp(e->type, type) || strcmp(e->name, name)) + continue; + + if (e->val <= (u64)UINT32_MAX) { + *v = lo32; + return true; + } + + if ((u32)e->val != lo32) { + fprintf(stderr, "ERROR: kernel BTF value of %s::%s (0x%x) doesn't match the low 32 bits of the vmlinux.h value (0x%llx); refusing to substitute\n", + type, name, lo32, (unsigned long long)e->val); + return false; + } + + if (!warned) { + fprintf(stderr, + "WARNING: kernel BTF lacks BTF_KIND_ENUM64 encoding (generated by\n" + "WARNING: pahole < 1.24 or with --skip_encoding_btf_enum64), so 64-bit\n" + "WARNING: scx enum values are truncated to their low 32 bits in kernel\n" + "WARNING: BTF. Substituting the full 64-bit values from the vmlinux.h\n" + "WARNING: this binary was built against, cross-checked against the low\n" + "WARNING: 32 bits the kernel does provide. The high 32 bits cannot be\n" + "WARNING: verified: if the running kernel's actual values differ from\n" + "WARNING: the build-time vmlinux.h (e.g. an enum that moved in a newer\n" + "WARNING: kernel), the scheduler will operate on bogus values, such as\n" + "WARNING: dispatching to nonexistent DSQ ids, and can wildly malfunction.\n"); + warned = true; + } + *v = e->val; + return true; + } + + /* + * Unknown enumerator (likely a stale autogen table). Fail + * pessimistically to avoid returning an invalid value. + */ + fprintf(stderr, "ERROR: kernel BTF truncates 64-bit enum %s::%s to 0x%x; 64-bit variant not found in vmlinux.h\n", + type, name, lo32); + return false; +} + static inline bool __COMPAT_read_enum(const char *type, const char *name, u64 *v) { const struct btf_type *t; @@ -46,6 +130,19 @@ static inline bool __COMPAT_read_enum(const char *type, const char *name, u64 *v n = btf__name_by_offset(__COMPAT_vmlinux_btf, e[i].name_off); SCX_BUG_ON(!n, "btf__name_by_offset()"); if (!strcmp(n, name)) { + /* + * Try to recover a 64-bit enum from an 8-byte + * BTF_KIND_ENUM that was encoded without ENUM64 + * support (old pahole or + * --skip_encoding_btf_enum64). Only scx_* + * types are covered by the substitution table; + * non-scx types fall through to the raw value + * so this generic utility keeps working for + * them. + */ + if (t->size == 8 && !strncmp(type, "scx_", 4)) + return __COMPAT_recover_truncated_enum64(type, name, + (u32)e[i].val, v); *v = e[i].val; return true; } diff --git a/tools/sched_ext/include/scx/enum_defs.autogen.h b/tools/sched_ext/include/scx/enum_defs.autogen.h index 19aa1de3e700..63b6b14b19bd 100644 --- a/tools/sched_ext/include/scx/enum_defs.autogen.h +++ b/tools/sched_ext/include/scx/enum_defs.autogen.h @@ -56,6 +56,10 @@ #define HAVE_SCX_DEQ_SLEEP #define HAVE_SCX_DEQ_CORE_SCHED_EXEC #define HAVE_SCX_DEQ_SCHED_CHANGE +#define HAVE_SCX_DSP_NONE +#define HAVE_SCX_DSP_LOCAL +#define HAVE_SCX_DSP_PREV +#define HAVE_SCX_DSP_RETRY #define HAVE_SCX_DSQ_FLAG_BUILTIN #define HAVE_SCX_DSQ_FLAG_LOCAL_ON #define HAVE_SCX_DSQ_INVALID @@ -188,7 +192,6 @@ #define HAVE_SCX_RQ_SUB_IDLE_RENOTIFY #define HAVE_SCX_RQ_ROOT_IDLE_RENOTIFY #define HAVE_SCX_RQ_IN_WAKEUP -#define HAVE_SCX_RQ_IN_BALANCE #define HAVE_SCX_RQ_IN_DISPATCH #define HAVE_SCX_SCHED_PCPU_BYPASSING #define HAVE_SCX_SLICE_OOB_DUR_BITS diff --git a/tools/sched_ext/include/scx/enums_abi.autogen.h b/tools/sched_ext/include/scx/enums_abi.autogen.h new file mode 100644 index 000000000000..d53899764f5a --- /dev/null +++ b/tools/sched_ext/include/scx/enums_abi.autogen.h @@ -0,0 +1,223 @@ +/* + * WARNING: This file is autogenerated from gen_enum_defs.py [1]. + * + * scx enumerator values from the vmlinux.h this tree is built against. + * Used as the substitution source when the running kernel's BTF lacks + * BTF_KIND_ENUM64 encoding and 64-bit enum values are truncated. + * + * [1] https://github.com/sched-ext/scx/blob/main/scripts/gen_enum_defs.py + */ + +#ifndef __ENUMS_ABI_AUTOGEN_H__ +#define __ENUMS_ABI_AUTOGEN_H__ + +struct __scx_enum_abi_val { + const char *type; + const char *name; + u64 val; +}; + +static const struct __scx_enum_abi_val __scx_enum_abi_vals[] + __attribute__((unused)) = { + { "scx_arena_consts", "SCX_ARENA_MIN_ORDER", 0x3LLU }, + { "scx_arena_consts", "SCX_ARENA_GROW_PAGES", 0x4LLU }, + { "scx_cap_flags", "__SCX_CAP_ENQ_IMMED", 0x0LLU }, + { "scx_cap_flags", "__SCX_CAP_ENQ", 0x1LLU }, + { "scx_cap_flags", "__SCX_CAP_PREEMPT", 0x2LLU }, + { "scx_cap_flags", "__SCX_CAP_PERF", 0x3LLU }, + { "scx_cap_flags", "__SCX_NR_CAPS", 0x4LLU }, + { "scx_cap_flags", "__SCX_CAP_ALL", 0xfLLU }, + { "scx_cap_flags", "SCX_CAP_ENQ_IMMED", 0x1LLU }, + { "scx_cap_flags", "SCX_CAP_ENQ", 0x2LLU }, + { "scx_cap_flags", "SCX_CAP_PREEMPT", 0x4LLU }, + { "scx_cap_flags", "SCX_CAP_PERF", 0x8LLU }, + { "scx_cap_flags", "SCX_CAP_BASE", 0x1LLU }, + { "scx_cap_flags", "SCX_CAPS_REENQ_ON_LOSS", 0x3LLU }, + { "scx_cid_consts", "SCX_CID_SHARD_SIZE_DFL", 0x18LLU }, + { "scx_cid_consts", "SCX_CID_SHARD_MAX_CPUS", 0x200LLU }, + { "scx_consts", "SCX_DSP_DFL_MAX_BATCH", 0x20LLU }, + { "scx_consts", "SCX_DSP_MAX_LOOPS", 0x20LLU }, + { "scx_consts", "SCX_WATCHDOG_MAX_TIMEOUT", 0x7530LLU }, + { "scx_consts", "SCX_RESCUE_DFL_BW_PPT", 0x14LLU }, + { "scx_consts", "SCX_RESCUE_MAX_BW_PPT", 0xfaLLU }, + { "scx_consts", "SCX_RESCUE_DISABLE", 0xffffffffLLU }, + { "scx_consts", "SCX_RESCUE_DFL_QUANTUM_US", 0x1388LLU }, + { "scx_consts", "SCX_RESCUE_MIN_QUANTUM_US", 0x3e8LLU }, + { "scx_consts", "SCX_RESCUE_MAX_QUANTUM_US", 0x186a0LLU }, + { "scx_consts", "SCX_RESCUE_MIN_SLICE_US", 0x3e8LLU }, + { "scx_consts", "SCX_RESCUE_OVERLOAD_MULT", 0x10LLU }, + { "scx_consts", "SCX_RESCUE_MIN_OVERLOAD_MS", 0x3e8LLU }, + { "scx_consts", "SCX_RESCUE_MAX_OVERLOAD_MS", 0x3a98LLU }, + { "scx_consts", "SCX_TID_CHUNK", 0x400LLU }, + { "scx_consts", "SCX_EXIT_BT_LEN", 0x40LLU }, + { "scx_consts", "SCX_EXIT_MSG_LEN", 0x400LLU }, + { "scx_consts", "SCX_EXIT_DUMP_DFL_LEN", 0x8000LLU }, + { "scx_consts", "SCX_CPUPERF_ONE", 0x400LLU }, + { "scx_consts", "SCX_TASK_ITER_BATCH", 0x20LLU }, + { "scx_consts", "SCX_BYPASS_HOST_NTH", 0x2LLU }, + { "scx_consts", "SCX_BYPASS_LB_DFL_INTV_US", 0x7a120LLU }, + { "scx_consts", "SCX_BYPASS_LB_DONOR_PCT", 0x7dLLU }, + { "scx_consts", "SCX_BYPASS_LB_MIN_DELTA_DIV", 0x4LLU }, + { "scx_consts", "SCX_BYPASS_LB_BATCH", 0x100LLU }, + { "scx_consts", "SCX_REENQ_MAX_REPEAT", 0x100LLU }, + { "scx_consts", "SCX_SUB_MAX_DEPTH", 0x4LLU }, + { "scx_cpu_preempt_reason", "SCX_CPU_PREEMPT_RT", 0x0LLU }, + { "scx_cpu_preempt_reason", "SCX_CPU_PREEMPT_DL", 0x1LLU }, + { "scx_cpu_preempt_reason", "SCX_CPU_PREEMPT_STOP", 0x2LLU }, + { "scx_cpu_preempt_reason", "SCX_CPU_PREEMPT_UNKNOWN", 0x3LLU }, + { "scx_deq_flags", "SCX_DEQ_SLEEP", 0x1LLU }, + { "scx_deq_flags", "SCX_DEQ_CORE_SCHED_EXEC", 0x100000000LLU }, + { "scx_deq_flags", "SCX_DEQ_SCHED_CHANGE", 0x200000000LLU }, + { "scx_dsp_verdict", "SCX_DSP_NONE", 0x0LLU }, + { "scx_dsp_verdict", "SCX_DSP_LOCAL", 0x1LLU }, + { "scx_dsp_verdict", "SCX_DSP_PREV", 0x2LLU }, + { "scx_dsp_verdict", "SCX_DSP_RETRY", 0x3LLU }, + { "scx_dsq_id_flags", "SCX_DSQ_FLAG_BUILTIN", 0x8000000000000000LLU }, + { "scx_dsq_id_flags", "SCX_DSQ_FLAG_LOCAL_ON", 0x4000000000000000LLU }, + { "scx_dsq_id_flags", "SCX_DSQ_INVALID", 0x8000000000000000LLU }, + { "scx_dsq_id_flags", "SCX_DSQ_GLOBAL", 0x8000000000000001LLU }, + { "scx_dsq_id_flags", "SCX_DSQ_LOCAL", 0x8000000000000002LLU }, + { "scx_dsq_id_flags", "SCX_DSQ_BYPASS", 0x8000000000000003LLU }, + { "scx_dsq_id_flags", "SCX_DSQ_REJECT", 0x8000000000000004LLU }, + { "scx_dsq_id_flags", "SCX_DSQ_RESCUE", 0x8000000000000005LLU }, + { "scx_dsq_id_flags", "SCX_DSQ_LOCAL_ON", 0xc000000000000000LLU }, + { "scx_dsq_id_flags", "SCX_DSQ_LOCAL_CPU_MASK", 0xffffffffLLU }, + { "scx_dsq_iter_flags", "SCX_DSQ_ITER_REV", 0x10000LLU }, + { "scx_dsq_iter_flags", "__SCX_DSQ_ITER_HAS_SLICE", 0x40000000LLU }, + { "scx_dsq_iter_flags", "__SCX_DSQ_ITER_HAS_VTIME", 0x80000000LLU }, + { "scx_dsq_iter_flags", "__SCX_DSQ_ITER_USER_FLAGS", 0x10000LLU }, + { "scx_dsq_iter_flags", "__SCX_DSQ_ITER_ALL_FLAGS", 0xc0010000LLU }, + { "scx_dsq_lnode_flags", "SCX_DSQ_LNODE_ITER_CURSOR", 0x1LLU }, + { "scx_dsq_lnode_flags", "__SCX_DSQ_LNODE_PRIV_SHIFT", 0x10LLU }, + { "scx_enable_state", "SCX_ENABLING", 0x0LLU }, + { "scx_enable_state", "SCX_ENABLED", 0x1LLU }, + { "scx_enable_state", "SCX_DISABLING", 0x2LLU }, + { "scx_enable_state", "SCX_DISABLED", 0x3LLU }, + { "scx_enq_flags", "SCX_ENQ_WAKEUP", 0x1LLU }, + { "scx_enq_flags", "SCX_ENQ_HEAD", 0x10000LLU }, + { "scx_enq_flags", "SCX_ENQ_CPU_SELECTED", 0x100000LLU }, + { "scx_enq_flags", "SCX_ENQ_PREEMPT", 0x100000000LLU }, + { "scx_enq_flags", "SCX_ENQ_IMMED", 0x200000000LLU }, + { "scx_enq_flags", "SCX_ENQ_RESCUE", 0x400000000LLU }, + { "scx_enq_flags", "SCX_ENQ_REENQ", 0x10000000000LLU }, + { "scx_enq_flags", "SCX_ENQ_LAST", 0x20000000000LLU }, + { "scx_enq_flags", "__SCX_ENQ_INTERNAL_MASK", 0xff00000000000000LLU }, + { "scx_enq_flags", "SCX_ENQ_CLEAR_OPSS", 0x100000000000000LLU }, + { "scx_enq_flags", "SCX_ENQ_DSQ_PRIQ", 0x200000000000000LLU }, + { "scx_enq_flags", "SCX_ENQ_NESTED", 0x400000000000000LLU }, + { "scx_enq_flags", "SCX_ENQ_GDSQ_FALLBACK", 0x800000000000000LLU }, + { "scx_enq_flags", "SCX_ENQ_IGNORE_CAPS", 0x1000000000000000LLU }, + { "scx_enq_flags", "SCX_ENQ_APPLY_SLICE", 0x2000000000000000LLU }, + { "scx_enq_flags", "SCX_ENQ_SLICE_DFL", 0x4000000000000000LLU }, + { "scx_ent_dsq_flags", "SCX_TASK_DSQ_ON_PRIQ", 0x1LLU }, + { "scx_ent_flags", "SCX_TASK_QUEUED", 0x1LLU }, + { "scx_ent_flags", "SCX_TASK_IN_CUSTODY", 0x2LLU }, + { "scx_ent_flags", "SCX_TASK_RESET_RUNNABLE_AT", 0x4LLU }, + { "scx_ent_flags", "SCX_TASK_DEQD_FOR_SLEEP", 0x8LLU }, + { "scx_ent_flags", "SCX_TASK_SUB_INIT", 0x10LLU }, + { "scx_ent_flags", "SCX_TASK_IMMED", 0x20LLU }, + { "scx_ent_flags", "SCX_TASK_PROTECTED", 0x40LLU }, + { "scx_ent_flags", "SCX_TASK_STATE_SHIFT", 0x8LLU }, + { "scx_ent_flags", "SCX_TASK_STATE_BITS", 0x3LLU }, + { "scx_ent_flags", "SCX_TASK_STATE_MASK", 0x700LLU }, + { "scx_ent_flags", "SCX_TASK_NONE", 0x0LLU }, + { "scx_ent_flags", "SCX_TASK_INIT_BEGIN", 0x100LLU }, + { "scx_ent_flags", "SCX_TASK_INIT", 0x200LLU }, + { "scx_ent_flags", "SCX_TASK_READY", 0x300LLU }, + { "scx_ent_flags", "SCX_TASK_ENABLED", 0x400LLU }, + { "scx_ent_flags", "SCX_TASK_DEAD", 0x500LLU }, + { "scx_ent_flags", "SCX_TASK_REENQ_REASON_SHIFT", 0xcLLU }, + { "scx_ent_flags", "SCX_TASK_REENQ_REASON_BITS", 0x3LLU }, + { "scx_ent_flags", "SCX_TASK_REENQ_REASON_MASK", 0x7000LLU }, + { "scx_ent_flags", "SCX_TASK_REENQ_NONE", 0x0LLU }, + { "scx_ent_flags", "SCX_TASK_REENQ_KFUNC", 0x1000LLU }, + { "scx_ent_flags", "SCX_TASK_REENQ_IMMED", 0x2000LLU }, + { "scx_ent_flags", "SCX_TASK_REENQ_PREEMPTED", 0x3000LLU }, + { "scx_ent_flags", "SCX_TASK_REENQ_CAP", 0x4000LLU }, + { "scx_ent_flags", "SCX_TASK_CURSOR", 0xffffffff80000000LLU }, + { "scx_exit_code", "SCX_ECODE_RSN_HOTPLUG", 0x100000000LLU }, + { "scx_exit_code", "SCX_ECODE_RSN_CGROUP_OFFLINE", 0x200000000LLU }, + { "scx_exit_code", "SCX_ECODE_ACT_RESTART", 0x1000000000000LLU }, + { "scx_exit_flags", "SCX_EFLAG_INITIALIZED", 0x1LLU }, + { "scx_exit_kind", "SCX_EXIT_NONE", 0x0LLU }, + { "scx_exit_kind", "SCX_EXIT_DONE", 0x1LLU }, + { "scx_exit_kind", "SCX_EXIT_UNREG", 0x40LLU }, + { "scx_exit_kind", "SCX_EXIT_UNREG_BPF", 0x41LLU }, + { "scx_exit_kind", "SCX_EXIT_UNREG_KERN", 0x42LLU }, + { "scx_exit_kind", "SCX_EXIT_SYSRQ", 0x43LLU }, + { "scx_exit_kind", "SCX_EXIT_PARENT", 0x44LLU }, + { "scx_exit_kind", "SCX_EXIT_PARENT_KILL", 0x45LLU }, + { "scx_exit_kind", "SCX_EXIT_ERROR", 0x400LLU }, + { "scx_exit_kind", "SCX_EXIT_ERROR_BPF", 0x401LLU }, + { "scx_exit_kind", "SCX_EXIT_ERROR_STALL", 0x402LLU }, + { "scx_exit_kind", "SCX_EXIT_ERROR_REENQ", 0x403LLU }, + { "scx_exit_kind", "SCX_EXIT_ERROR_RESCUE", 0x404LLU }, + { "scx_kf_allow_flags", "SCX_KF_ALLOW_UNLOCKED", 0x1LLU }, + { "scx_kf_allow_flags", "SCX_KF_ALLOW_INIT_CIDS", 0x2LLU }, + { "scx_kf_allow_flags", "SCX_KF_ALLOW_CPU_RELEASE", 0x4LLU }, + { "scx_kf_allow_flags", "SCX_KF_ALLOW_DISPATCH", 0x8LLU }, + { "scx_kf_allow_flags", "SCX_KF_ALLOW_ENQUEUE", 0x10LLU }, + { "scx_kf_allow_flags", "SCX_KF_ALLOW_SELECT_CPU", 0x20LLU }, + { "scx_kick_flags", "SCX_KICK_IDLE", 0x1LLU }, + { "scx_kick_flags", "SCX_KICK_PREEMPT", 0x2LLU }, + { "scx_kick_flags", "SCX_KICK_WAIT", 0x4LLU }, + { "scx_opi", "SCX_OPI_BEGIN", 0x0LLU }, + { "scx_opi", "SCX_OPI_NORMAL_BEGIN", 0x0LLU }, + { "scx_opi", "SCX_OPI_NORMAL_END", 0x21LLU }, + { "scx_opi", "SCX_OPI_CPU_HOTPLUG_BEGIN", 0x21LLU }, + { "scx_opi", "SCX_OPI_CPU_HOTPLUG_END", 0x23LLU }, + { "scx_opi", "SCX_OPI_END", 0x23LLU }, + { "scx_ops_flags", "SCX_OPS_KEEP_BUILTIN_IDLE", 0x1LLU }, + { "scx_ops_flags", "SCX_OPS_ENQ_LAST", 0x2LLU }, + { "scx_ops_flags", "SCX_OPS_ENQ_EXITING", 0x4LLU }, + { "scx_ops_flags", "SCX_OPS_SWITCH_PARTIAL", 0x8LLU }, + { "scx_ops_flags", "SCX_OPS_ENQ_MIGRATION_DISABLED", 0x10LLU }, + { "scx_ops_flags", "SCX_OPS_ALLOW_QUEUED_WAKEUP", 0x20LLU }, + { "scx_ops_flags", "SCX_OPS_BUILTIN_IDLE_PER_NODE", 0x40LLU }, + { "scx_ops_flags", "SCX_OPS_ALWAYS_ENQ_IMMED", 0x80LLU }, + { "scx_ops_flags", "SCX_OPS_TID_TO_TASK", 0x100LLU }, + { "scx_ops_flags", "SCX_OPS_ALL_FLAGS", 0x1ffLLU }, + { "scx_ops_flags", "__SCX_OPS_INTERNAL_MASK", 0xff00000000000000LLU }, + { "scx_ops_flags", "SCX_OPS_HAS_CPU_PREEMPT", 0x100000000000000LLU }, + { "scx_ops_state", "SCX_OPSS_NONE", 0x0LLU }, + { "scx_ops_state", "SCX_OPSS_QUEUEING", 0x1LLU }, + { "scx_ops_state", "SCX_OPSS_QUEUED", 0x2LLU }, + { "scx_ops_state", "SCX_OPSS_DISPATCHING", 0x3LLU }, + { "scx_ops_state", "SCX_OPSS_QSEQ_SHIFT", 0x2LLU }, + { "scx_pick_idle_cpu_flags", "SCX_PICK_IDLE_CORE", 0x1LLU }, + { "scx_pick_idle_cpu_flags", "SCX_PICK_IDLE_IN_NODE", 0x2LLU }, + { "scx_public_consts", "SCX_OPS_NAME_LEN", 0x80LLU }, + { "scx_public_consts", "SCX_SLICE_DFL", 0x1312d00LLU }, + { "scx_public_consts", "SCX_SLICE_BYPASS", 0x4c4b40LLU }, + { "scx_public_consts", "SCX_SLICE_INF", 0xffffffffffffffffLLU }, + { "scx_reenq_flags", "SCX_REENQ_ANY", 0x1LLU }, + { "scx_reenq_flags", "SCX_REENQ_CAP_REVOKE", 0x2LLU }, + { "scx_reenq_flags", "__SCX_REENQ_FILTER_MASK", 0xffffLLU }, + { "scx_reenq_flags", "__SCX_REENQ_USER_MASK", 0x1LLU }, + { "scx_reenq_flags", "SCX_REENQ_TSR_RQ_OPEN", 0x100000000LLU }, + { "scx_reenq_flags", "SCX_REENQ_TSR_NOT_FIRST", 0x200000000LLU }, + { "scx_reenq_flags", "__SCX_REENQ_TSR_MASK", 0xf00000000LLU }, + { "scx_rq_flags", "SCX_RQ_ONLINE", 0x1LLU }, + { "scx_rq_flags", "SCX_RQ_CAN_STOP_TICK", 0x2LLU }, + { "scx_rq_flags", "SCX_RQ_CLK_VALID", 0x20LLU }, + { "scx_rq_flags", "SCX_RQ_BAL_CB_PENDING", 0x40LLU }, + { "scx_rq_flags", "SCX_RQ_SUB_IDLE_RENOTIFY", 0x80LLU }, + { "scx_rq_flags", "SCX_RQ_ROOT_IDLE_RENOTIFY", 0x100LLU }, + { "scx_rq_flags", "SCX_RQ_IN_WAKEUP", 0x10000LLU }, + { "scx_rq_flags", "SCX_RQ_IN_DISPATCH", 0x20000LLU }, + { "scx_sched_pcpu_flags", "SCX_SCHED_PCPU_BYPASSING", 0x1LLU }, + { "scx_slice_oob_consts", "SCX_SLICE_OOB_DUR_BITS", 0x2bLLU }, + { "scx_slice_oob_consts", "SCX_SLICE_OOB_ID_BITS", 0x14LLU }, + { "scx_slice_oob_consts", "SCX_SLICE_OOB_DUR_MASK", 0x7ffffffffffLLU }, + { "scx_slice_oob_consts", "SCX_SLICE_OOB_ID_SHIFT", 0x2bLLU }, + { "scx_slice_oob_consts", "SCX_SLICE_OOB_ID_MASK", 0xfffffLLU }, + { "scx_slice_oob_consts", "SCX_SLICE_OOB_PENDING", 0x8000000000000000LLU }, + { "scx_tg_flags", "SCX_TG_ONLINE", 0x1LLU }, + { "scx_tg_flags", "SCX_TG_INITED", 0x2LLU }, + { "scx_tg_flags", "SCX_TG_SUB_INIT", 0x4LLU }, + { "scx_wake_flags", "SCX_WAKE_FORK", 0x4LLU }, + { "scx_wake_flags", "SCX_WAKE_TTWU", 0x8LLU }, + { "scx_wake_flags", "SCX_WAKE_SYNC", 0x10LLU }, +}; + +#endif /* __ENUMS_ABI_AUTOGEN_H__ */ diff --git a/tools/sched_ext/scx_central.bpf.c b/tools/sched_ext/scx_central.bpf.c index 64dd60b3e922..65dae9e45400 100644 --- a/tools/sched_ext/scx_central.bpf.c +++ b/tools/sched_ext/scx_central.bpf.c @@ -299,6 +299,7 @@ static int central_timerfn(void *map, int *key, struct bpf_timer *timer) u64 now = scx_bpf_now(); u64 nr_to_kick = nr_queued; s32 i, curr_cpu; + int ret; curr_cpu = bpf_get_smp_processor_id(); if (timer_pinned && (curr_cpu != central_cpu)) { @@ -332,7 +333,10 @@ static int central_timerfn(void *map, int *key, struct bpf_timer *timer) scx_bpf_kick_cpu(cpu, SCX_KICK_PREEMPT); } - bpf_timer_start(timer, TIMER_INTERVAL_NS, BPF_F_TIMER_CPU_PIN); + ret = bpf_timer_start(timer, TIMER_INTERVAL_NS, + timer_pinned ? BPF_F_TIMER_CPU_PIN : 0); + if (ret) + scx_bpf_error("bpf_timer_start failed (%d)", ret); __sync_fetch_and_add(&nr_timers, 1); return 0; } diff --git a/tools/sched_ext/scx_flatcg.bpf.c b/tools/sched_ext/scx_flatcg.bpf.c index 64cf4dd964d6..454ebb820c5e 100644 --- a/tools/sched_ext/scx_flatcg.bpf.c +++ b/tools/sched_ext/scx_flatcg.bpf.c @@ -937,7 +937,7 @@ void BPF_STRUCT_OPS(fcg_cgroup_move, struct task_struct *p, if (!(from_cgc = find_cgrp_ctx(from)) || !(to_cgc = find_cgrp_ctx(to))) return; - delta = time_delta(p->scx.dsq_vtime, from_cgc->tvtime_now); + delta = (s64)(p->scx.dsq_vtime - from_cgc->tvtime_now); scx_bpf_task_set_dsq_vtime(p, to_cgc->tvtime_now + delta); } diff --git a/tools/sched_ext/scx_qmap.bpf.c b/tools/sched_ext/scx_qmap.bpf.c index 5bb8b90a275a..9f6e61d7ca07 100644 --- a/tools/sched_ext/scx_qmap.bpf.c +++ b/tools/sched_ext/scx_qmap.bpf.c @@ -1246,7 +1246,8 @@ static int monitor_timerfn(void *map, int *key, struct bpf_timer *timer) scx_read_event(&events, SCX_EV_BYPASS_ACTIVATE)); } - bpf_timer_start(timer, ONE_SEC_IN_NS, 0); + if (bpf_timer_start(timer, ONE_SEC_IN_NS, 0)) + scx_bpf_error("failed to re-arm stats timer"); return 0; } @@ -1268,7 +1269,8 @@ struct { static int lowpri_timerfn(void *map, int *key, struct bpf_timer *timer) { scx_bpf_dsq_reenq(LOWPRI_DSQ, 0); - bpf_timer_start(timer, LOWPRI_INTV_NS, 0); + if (bpf_timer_start(timer, LOWPRI_INTV_NS, 0)) + scx_bpf_error("failed to re-arm lowpri timer"); return 0; } @@ -1747,7 +1749,8 @@ static void rr_advance(void) static int round_robin_timerfn(void *map, int *key, struct bpf_timer *timer) { rr_advance(); - bpf_timer_start(timer, round_robin_ns, 0); + if (bpf_timer_start(timer, round_robin_ns, 0)) + scx_bpf_error("failed to re-arm round-robin timer"); return 0; }