> On Tue, 18 Oct 2022 20:10:47 +0200 > "Uladzislau Rezki (Sony)" <urezki@xxxxxxxxx> wrote: > > > It is for a debug purpose and for validation of passed parameters. > > > > Signed-off-by: Uladzislau Rezki (Sony) <urezki@xxxxxxxxx> > > --- > > include/trace/events/vmalloc.h | 56 ++++++++++++++++++++++++++++++++++ > > 1 file changed, 56 insertions(+) > > create mode 100644 include/trace/events/vmalloc.h > > > > diff --git a/include/trace/events/vmalloc.h b/include/trace/events/vmalloc.h > > new file mode 100644 > > index 000000000000..39fbd77c91e7 > > --- /dev/null > > +++ b/include/trace/events/vmalloc.h > > @@ -0,0 +1,56 @@ > > +/* SPDX-License-Identifier: GPL-2.0 */ > > +#undef TRACE_SYSTEM > > +#define TRACE_SYSTEM vmalloc > > + > > +#if !defined(_TRACE_VMALLOC_H) || defined(TRACE_HEADER_MULTI_READ) > > +#define _TRACE_VMALLOC_H > > + > > +#include <linux/tracepoint.h> > > + > > +/** > > + * alloc_vmap_area - called when a new vmap allocation occurs > > + * @addr: an allocated address > > + * @size: a requested size > > + * @align: a requested alignment > > + * @vstart: a requested start range > > + * @vend: a requested end range > > + * @failed: an allocation failed or not > > + * > > + * This event is used for a debug purpose, it can give an extra > > + * information for a developer about how often it occurs and which > > + * parameters are passed for further validation. > > + */ > > +TRACE_EVENT(alloc_vmap_area, > > + > > + TP_PROTO(unsigned long addr, unsigned long size, unsigned long align, > > + unsigned long vstart, unsigned long vend, int failed), > > + > > + TP_ARGS(addr, size, align, vstart, vend, failed), > > The above is passed in via (from patch 4): > > > @@ -1621,6 +1624,8 @@ static struct vmap_area *alloc_vmap_area(unsigned long size, > size, align, vstart, vend); > spin_unlock(&free_vmap_area_lock); > > + trace_alloc_vmap_area(addr, size, align, vstart, vend, addr == vend); > + > /* > * If an allocation fails, the "vend" address is > * returned. Therefore trigger the overflow path. > > > + > > + TP_STRUCT__entry( > > + __field(unsigned long, addr) > > + __field(unsigned long, size) > > + __field(unsigned long, align) > > + __field(unsigned long, vstart) > > + __field(unsigned long, vend) > > > + __field(int, failed) > > I would drop the failed field... > > > + ), > > + > > + TP_fast_assign( > > + __entry->addr = addr; > > + __entry->size = size; > > + __entry->align = align; > > + __entry->vstart = vstart; > > + __entry->vend = vend; > > And instead have: > > __entry->failed = addr == vend; > > Why pass in a parameter that can be calculated in the trace event logic? > It can be. A condition about when it is failed or not is taken on upper level because it might be changed afterwards. So a trace event is not aware about it thus no need in adaptation. But i do not have a strong opinion here. I can prepare a patch to eliminate it. What is your preference? -- Uladzislau Rezki
