On Sun, Apr 07, 2024 at 12:47:14AM +0800, Kuan-Wei Chiu wrote: > -struct min_heap { > - void *data; > - int nr; > - int size; > -}; > +#define MIN_HEAP_PREALLOCATED(_type, _name, _nr) \ > +struct _name { \ > + int nr; \ > + int size; \ > + _type *data; \ > + _type preallocated[_nr]; \ > +} > @@ -3738,7 +3739,7 @@ static noinline int visit_groups_merge(struct perf_event_context *ctx, > struct perf_cpu_context *cpuctx = NULL; > /* Space for per CPU and/or any CPU event iterators. */ > struct perf_event *itrs[2]; > - struct min_heap event_heap; > + struct perf_event_min_heap event_heap; > struct perf_event **evt; > int ret; > > @@ -3747,11 +3748,9 @@ static noinline int visit_groups_merge(struct perf_event_context *ctx, > > if (!ctx->task) { > cpuctx = this_cpu_ptr(&perf_cpu_context); > - event_heap = (struct min_heap){ > - .data = cpuctx->heap, > - .nr = 0, > - .size = cpuctx->heap_size, > - }; > + event_heap.data = cpuctx->heap; > + event_heap.nr = 0; > + event_heap.size = cpuctx->heap_size; > > lockdep_assert_held(&cpuctx->ctx.lock); > > @@ -3760,11 +3759,9 @@ static noinline int visit_groups_merge(struct perf_event_context *ctx, > css = &cpuctx->cgrp->css; > #endif > } else { > - event_heap = (struct min_heap){ > - .data = itrs, > - .nr = 0, > - .size = ARRAY_SIZE(itrs), > - }; > + event_heap.data = itrs; > + event_heap.nr = 0; > + event_heap.size = ARRAY_SIZE(itrs); > /* Events not within a CPU context may be on any CPU. */ > __heap_add(&event_heap, perf_event_groups_first(groups, -1, pmu, NULL)); > } Not too happy about these. If you ever add more fields they will go uninitialized. Why not keep the existing form and fix the struct name?