On Fri, Apr 12, 2024 at 09:30:17AM +0200, Peter Zijlstra wrote: > 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? Sorry for the late reply. I'm traveling. I'll change that back in v4. Regards, Kuan-Wei