Commit 6030fd5f authored by Uladzislau Rezki (Sony)'s avatar Uladzislau Rezki (Sony) Committed by Andrew Morton
Browse files

mm: vmalloc: use trace_purge_vmap_area_lazy event 

This is for debug purposes and is called when all outstanding areas are
removed back to the vmap space.  It gives some extra information about:

- a start:end range where set of vmap ares were freed;
- a number of purged areas which were backed off.

[urezki@gmail.com: simplify return boolean expression]
  Link: https://lkml.kernel.org/r/20221020125247.5053-1-urezki@gmail.com
Link: https://lkml.kernel.org/r/20221018181053.434508-6-urezki@gmail.com


Signed-off-by: default avatarUladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: default avatarSteven Rostedt (Google) <rostedt@goodmis.org>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sony.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent cf243da6

mm/vmalloc.c

+7 −2
Original line number Diff line number Diff line
@@ -1730,6 +1730,7 @@ static void purge_fragmented_blocks_allcpus(void); 
static bool __purge_vmap_area_lazy(unsigned long start, unsigned long end)

{

	unsigned long resched_threshold;

	unsigned int num_purged_areas = 0;

	struct list_head local_purge_list;

	struct vmap_area *va, *n_va;
@@ -1741,7 +1742,7 @@ static bool __purge_vmap_area_lazy(unsigned long start, unsigned long end) 
	spin_unlock(&purge_vmap_area_lock);



	if (unlikely(list_empty(&local_purge_list)))

		return false;

		goto out;



	start = min(start,

		list_first_entry(&local_purge_list,
@@ -1776,12 +1777,16 @@ static bool __purge_vmap_area_lazy(unsigned long start, unsigned long end) 
					      va->va_start, va->va_end);



		atomic_long_sub(nr, &vmap_lazy_nr);

		num_purged_areas++;



		if (atomic_long_read(&vmap_lazy_nr) < resched_threshold)

			cond_resched_lock(&free_vmap_area_lock);

	}

	spin_unlock(&free_vmap_area_lock);

	return true;



out:

	trace_purge_vmap_area_lazy(start, end, num_purged_areas);

	return num_purged_areas > 0;

}



/*