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The hand-rolled bracket reset locked_rq to > NULL on exit instead of restoring the saved value, so a nested call would > clobber the outer op's locked-rq tracking. > > Parameterize the dispatch macros by the ops-table member and add > SCX_CALL_CID_OP_TASK(), which routes through sch->ops_cid. Convert > scx_call_op_set_cpumask() to it and drop the hand-rolled bracket. The only > behavioral change is that locked_rq is now saved and restored like every > other op call site. > > Signed-off-by: Tejun Heo Reviewed-by: Andrea Righi Thanks, -Andrea > --- > kernel/sched/ext/ext.c | 14 +++----------- > kernel/sched/ext/internal.h | 23 ++++++++++++++++++++--- > 2 files changed, 23 insertions(+), 14 deletions(-) > > diff --git a/kernel/sched/ext/ext.c b/kernel/sched/ext/ext.c > index f4725698f5ef..c050a68189d4 100644 > --- a/kernel/sched/ext/ext.c > +++ b/kernel/sched/ext/ext.c > @@ -410,11 +410,6 @@ static inline void scx_call_op_set_cpumask(struct scx_sched *sch, struct rq *rq, > struct task_struct *task, > const struct cpumask *cpumask) > { > - WARN_ON_ONCE(current->scx.kf_tasks[0]); > - current->scx.kf_tasks[0] = task; > - if (rq) > - update_locked_rq(rq); > - > if (scx_is_cid_type()) { > struct scx_cmask *kern_va = *this_cpu_ptr(sch->set_cmask_scratch); > /* > @@ -423,14 +418,11 @@ static inline void scx_call_op_set_cpumask(struct scx_sched *sch, struct rq *rq, > * the sole user of the scratch area. > */ > scx_cpumask_to_cmask(cpumask, kern_va); > - sch->ops_cid.set_cmask(task, scx_kaddr_to_arena(sch, kern_va)); > + SCX_CALL_CID_OP_TASK(sch, set_cmask, rq, task, > + scx_kaddr_to_arena(sch, kern_va)); > } else { > - sch->ops.set_cpumask(task, cpumask); > + SCX_CALL_OP_TASK(sch, set_cpumask, rq, task, cpumask); > } > - > - if (rq) > - update_locked_rq(NULL); > - current->scx.kf_tasks[0] = NULL; > } > > enum scx_dsq_iter_flags { > diff --git a/kernel/sched/ext/internal.h b/kernel/sched/ext/internal.h > index f9fe7c6ebc4b..5ca44ad88786 100644 > --- a/kernel/sched/ext/internal.h > +++ b/kernel/sched/ext/internal.h > @@ -1751,8 +1751,11 @@ static inline void update_locked_rq(struct rq *rq) > /* > * SCX ops can recurse via scx_bpf_sub_dispatch() - the inner call must not > * clobber the outer's scx_locked_rq_state. Save it on entry, restore on exit. > + * > + * @ops is the ops table to dispatch through: ops for the cpu form, ops_cid > + * for the cid form. > */ > -#define SCX_CALL_OP(sch, op, locked_rq, args...) \ > +#define __SCX_CALL_OP(sch, ops, op, locked_rq, args...) \ > do { \ > struct rq *__prev_locked_rq; \ > \ > @@ -1765,6 +1768,9 @@ do { \ > update_locked_rq(__prev_locked_rq); \ > } while (0) > > +#define SCX_CALL_OP(sch, op, locked_rq, args...) \ > + __SCX_CALL_OP(sch, ops, op, locked_rq, ##args) > + > #define SCX_CALL_OP_RET(sch, op, locked_rq, args...) \ > ({ \ > struct rq *__prev_locked_rq; \ > @@ -1796,14 +1802,25 @@ do { \ > * WARN_ON_ONCE() in each macro catches a re-entry of any of the three variants > * while a previous one is still in progress. > */ > -#define SCX_CALL_OP_TASK(sch, op, locked_rq, task, args...) \ > +#define __SCX_CALL_OP_TASK(sch, ops, op, locked_rq, task, args...) \ > do { \ > WARN_ON_ONCE(current->scx.kf_tasks[0]); \ > current->scx.kf_tasks[0] = task; \ > - SCX_CALL_OP((sch), op, locked_rq, task, ##args); \ > + __SCX_CALL_OP((sch), ops, op, locked_rq, task, ##args); \ > current->scx.kf_tasks[0] = NULL; \ > } while (0) > > +#define SCX_CALL_OP_TASK(sch, op, locked_rq, task, args...) \ > + __SCX_CALL_OP_TASK(sch, ops, op, locked_rq, task, ##args) > + > +/* > + * Dispatch a task op through the cid-form ops_cid table. Only set_cmask() needs > + * this: it takes an arena cmask address instead of a cpumask, so it cannot be > + * invoked via its cpu-form set_cpumask() slot. > + */ > +#define SCX_CALL_CID_OP_TASK(sch, op, locked_rq, task, args...) \ > + __SCX_CALL_OP_TASK(sch, ops_cid, op, locked_rq, task, ##args) > + > #define SCX_CALL_OP_TASK_RET(sch, op, locked_rq, task, args...) \ > ({ \ > __typeof__((sch)->ops.op(task, ##args)) __ret; \ > -- > 2.54.0 >