Re: [PATCH 1/4] sched_ext: scx_qmap: rename tctx to taskc

[Emil Tsalapatis]

On Thu, Apr 16, 2026 at 1:16 AM Tejun Heo <tj@xxxxxxxxxx> wrote:
>
> >
> Rename the per-task context local variable from tctx to taskc for
> consistency.
>
> No functional change.
>

Reviewed-by: Emil Tsalapatis <emil@xxxxxxxxxxxxxxx>

> Signed-off-by: Tejun Heo <tj@xxxxxxxxxx>
> ---
>  tools/sched_ext/scx_qmap.bpf.c | 60 +++++++++++++++++-----------------
>  1 file changed, 30 insertions(+), 30 deletions(-)
>
> diff --git a/tools/sched_ext/scx_qmap.bpf.c b/tools/sched_ext/scx_qmap.bpf.c
> index b68abb9e760b..a18234f3c27a 100644
> --- a/tools/sched_ext/scx_qmap.bpf.c
> +++ b/tools/sched_ext/scx_qmap.bpf.c
> @@ -159,22 +159,22 @@ static s32 pick_direct_dispatch_cpu(struct task_struct *p, s32 prev_cpu)
>
>  static struct task_ctx *lookup_task_ctx(struct task_struct *p)
>  {
> -       struct task_ctx *tctx;
> +       struct task_ctx *taskc;
>
> -       if (!(tctx = bpf_task_storage_get(&task_ctx_stor, p, 0, 0))) {
> +       if (!(taskc = bpf_task_storage_get(&task_ctx_stor, p, 0, 0))) {
>                 scx_bpf_error("task_ctx lookup failed");
>                 return NULL;
>         }
> -       return tctx;
> +       return taskc;
>  }
>
>  s32 BPF_STRUCT_OPS(qmap_select_cpu, struct task_struct *p,
>                    s32 prev_cpu, u64 wake_flags)
>  {
> -       struct task_ctx *tctx;
> +       struct task_ctx *taskc;
>         s32 cpu;
>
> -       if (!(tctx = lookup_task_ctx(p)))
> +       if (!(taskc = lookup_task_ctx(p)))
>                 return -ESRCH;
>
>         if (p->scx.weight < 2 && !(p->flags & PF_KTHREAD))
> @@ -183,7 +183,7 @@ s32 BPF_STRUCT_OPS(qmap_select_cpu, struct task_struct *p,
>         cpu = pick_direct_dispatch_cpu(p, prev_cpu);
>
>         if (cpu >= 0) {
> -               tctx->force_local = true;
> +               taskc->force_local = true;
>                 return cpu;
>         } else {
>                 return prev_cpu;
> @@ -208,7 +208,7 @@ static int weight_to_idx(u32 weight)
>  void BPF_STRUCT_OPS(qmap_enqueue, struct task_struct *p, u64 enq_flags)
>  {
>         static u32 user_cnt, kernel_cnt;
> -       struct task_ctx *tctx;
> +       struct task_ctx *taskc;
>         u32 pid = p->pid;
>         int idx = weight_to_idx(p->scx.weight);
>         void *ring;
> @@ -231,14 +231,14 @@ void BPF_STRUCT_OPS(qmap_enqueue, struct task_struct *p, u64 enq_flags)
>         if (test_error_cnt && !--test_error_cnt)
>                 scx_bpf_error("test triggering error");
>
> -       if (!(tctx = lookup_task_ctx(p)))
> +       if (!(taskc = lookup_task_ctx(p)))
>                 return;
>
>         /*
>          * All enqueued tasks must have their core_sched_seq updated for correct
>          * core-sched ordering. Also, take a look at the end of qmap_dispatch().
>          */
> -       tctx->core_sched_seq = core_sched_tail_seqs[idx]++;
> +       taskc->core_sched_seq = core_sched_tail_seqs[idx]++;
>
>         /*
>          * IMMED stress testing: Every immed_stress_nth'th enqueue, dispatch
> @@ -249,7 +249,7 @@ void BPF_STRUCT_OPS(qmap_enqueue, struct task_struct *p, u64 enq_flags)
>                 static u32 immed_stress_cnt;
>
>                 if (!(++immed_stress_cnt % immed_stress_nth)) {
> -                       tctx->force_local = false;
> +                       taskc->force_local = false;
>                         scx_bpf_dsq_insert(p, SCX_DSQ_LOCAL_ON | scx_bpf_task_cpu(p),
>                                            slice_ns, enq_flags);
>                         return;
> @@ -260,8 +260,8 @@ void BPF_STRUCT_OPS(qmap_enqueue, struct task_struct *p, u64 enq_flags)
>          * If qmap_select_cpu() is telling us to or this is the last runnable
>          * task on the CPU, enqueue locally.
>          */
> -       if (tctx->force_local) {
> -               tctx->force_local = false;
> +       if (taskc->force_local) {
> +               taskc->force_local = false;
>                 scx_bpf_dsq_insert(p, SCX_DSQ_LOCAL, slice_ns, enq_flags);
>                 return;
>         }
> @@ -310,7 +310,7 @@ void BPF_STRUCT_OPS(qmap_enqueue, struct task_struct *p, u64 enq_flags)
>         }
>
>         if (highpri_boosting && p->scx.weight >= HIGHPRI_WEIGHT) {
> -               tctx->highpri = true;
> +               taskc->highpri = true;
>                 __sync_fetch_and_add(&nr_highpri_queued, 1);
>         }
>         __sync_fetch_and_add(&nr_enqueued, 1);
> @@ -330,10 +330,10 @@ void BPF_STRUCT_OPS(qmap_dequeue, struct task_struct *p, u64 deq_flags)
>  static void update_core_sched_head_seq(struct task_struct *p)
>  {
>         int idx = weight_to_idx(p->scx.weight);
> -       struct task_ctx *tctx;
> +       struct task_ctx *taskc;
>
> -       if ((tctx = lookup_task_ctx(p)))
> -               core_sched_head_seqs[idx] = tctx->core_sched_seq;
> +       if ((taskc = lookup_task_ctx(p)))
> +               core_sched_head_seqs[idx] = taskc->core_sched_seq;
>  }
>
>  /*
> @@ -354,12 +354,12 @@ static bool dispatch_highpri(bool from_timer)
>         /* scan SHARED_DSQ and move highpri tasks to HIGHPRI_DSQ */
>         bpf_for_each(scx_dsq, p, SHARED_DSQ, 0) {
>                 static u64 highpri_seq;
> -               struct task_ctx *tctx;
> +               struct task_ctx *taskc;
>
> -               if (!(tctx = lookup_task_ctx(p)))
> +               if (!(taskc = lookup_task_ctx(p)))
>                         return false;
>
> -               if (tctx->highpri) {
> +               if (taskc->highpri) {
>                         /* exercise the set_*() and vtime interface too */
>                         scx_bpf_dsq_move_set_slice(BPF_FOR_EACH_ITER, slice_ns * 2);
>                         scx_bpf_dsq_move_set_vtime(BPF_FOR_EACH_ITER, highpri_seq++);
> @@ -405,7 +405,7 @@ void BPF_STRUCT_OPS(qmap_dispatch, s32 cpu, struct task_struct *prev)
>  {
>         struct task_struct *p;
>         struct cpu_ctx *cpuc;
> -       struct task_ctx *tctx;
> +       struct task_ctx *taskc;
>         u32 zero = 0, batch = dsp_batch ?: 1;
>         void *fifo;
>         s32 i, pid;
> @@ -450,7 +450,7 @@ void BPF_STRUCT_OPS(qmap_dispatch, s32 cpu, struct task_struct *prev)
>
>                 /* Dispatch or advance. */
>                 bpf_repeat(BPF_MAX_LOOPS) {
> -                       struct task_ctx *tctx;
> +                       struct task_ctx *taskc;
>
>                         if (bpf_map_pop_elem(fifo, &pid))
>                                 break;
> @@ -459,12 +459,12 @@ void BPF_STRUCT_OPS(qmap_dispatch, s32 cpu, struct task_struct *prev)
>                         if (!p)
>                                 continue;
>
> -                       if (!(tctx = lookup_task_ctx(p))) {
> +                       if (!(taskc = lookup_task_ctx(p))) {
>                                 bpf_task_release(p);
>                                 return;
>                         }
>
> -                       if (tctx->highpri)
> +                       if (taskc->highpri)
>                                 __sync_fetch_and_sub(&nr_highpri_queued, 1);
>
>                         update_core_sched_head_seq(p);
> @@ -539,13 +539,13 @@ void BPF_STRUCT_OPS(qmap_dispatch, s32 cpu, struct task_struct *prev)
>          * if the task were enqueued and dispatched immediately.
>          */
>         if (prev) {
> -               tctx = bpf_task_storage_get(&task_ctx_stor, prev, 0, 0);
> -               if (!tctx) {
> +               taskc = bpf_task_storage_get(&task_ctx_stor, prev, 0, 0);
> +               if (!taskc) {
>                         scx_bpf_error("task_ctx lookup failed");
>                         return;
>                 }
>
> -               tctx->core_sched_seq =
> +               taskc->core_sched_seq =
>                         core_sched_tail_seqs[weight_to_idx(prev->scx.weight)]++;
>         }
>  }
> @@ -580,16 +580,16 @@ void BPF_STRUCT_OPS(qmap_tick, struct task_struct *p)
>  static s64 task_qdist(struct task_struct *p)
>  {
>         int idx = weight_to_idx(p->scx.weight);
> -       struct task_ctx *tctx;
> +       struct task_ctx *taskc;
>         s64 qdist;
>
> -       tctx = bpf_task_storage_get(&task_ctx_stor, p, 0, 0);
> -       if (!tctx) {
> +       taskc = bpf_task_storage_get(&task_ctx_stor, p, 0, 0);
> +       if (!taskc) {
>                 scx_bpf_error("task_ctx lookup failed");
>                 return 0;
>         }
>
> -       qdist = tctx->core_sched_seq - core_sched_head_seqs[idx];
> +       qdist = taskc->core_sched_seq - core_sched_head_seqs[idx];
>
>         /*
>          * As queue index increments, the priority doubles. The queue w/ index 3
> --
> 2.53.0
>
>