Re: [PATCH] mm: Use BUG_ON instead of if condition followed by BUG
From: Matthew Wilcox <willy@infradead.org>
Date: 2021-11-25 03:34:42
Also in:
lkml
On Wed, Nov 24, 2021 at 02:45:59PM -0800, John Hubbard wrote:
quoted hunk ↗ jump to hunk
@@ -2201,13 +2201,12 @@ static int __ref try_remove_memory(u64 start, u64 size)*/ void __remove_memory(u64 start, u64 size) { - + int ret = try_remove_memory(start, size); /* * trigger BUG() if some memory is not offlined prior to calling this * function */ - if (try_remove_memory(start, size)) - BUG(); + BUG_ON(ret); }
I'd rather leave it the way it is. I don't see why the version you propose is better.
...and by the way, while going to type that, I immediately stumbled upon
another pre-existing case of this sort of thing, in try_remove_memory(),
which does this:
static int __ref try_remove_memory(u64 start, u64 size)
{
struct vmem_altmap mhp_altmap = {};
struct vmem_altmap *altmap = NULL;
unsigned long nr_vmemmap_pages;
int rc = 0, nid = NUMA_NO_NODE;
BUG_ON(check_hotplug_memory_range(start, size));That needs to be fixed.