On Mon, 1 Dec 2025 13:18:48 -0500 Audra Mitchell <[email protected]> wrote:
> If PAGE_SIZE is larger than 4k and if you have a system with a > large number of CPUs, this test can require a very large amount > of memory leading to oom-killer firing. Given the type of allocation, > the kernel won't have anything to kill, causing the system to > stall. Add a parameter to the test_vmalloc driver to represent the > number of times a percpu object will be allocated. Calculate this > in test_vmalloc.sh to be 90% of available memory or the current > default of 35000, whichever is smaller. > > ... > > --- a/lib/test_vmalloc.c > +++ b/lib/test_vmalloc.c > @@ -57,6 +57,9 @@ __param(int, run_test_mask, 7, > /* Add a new test case description here. */ > ); > > +__param(int, nr_pcpu_objects, 35000, > + "Number of pcpu objects to allocate for pcpu_alloc_test"); > + > /* > * This is for synchronization of setup phase. > */ > @@ -292,24 +295,24 @@ pcpu_alloc_test(void) > size_t size, align; > int i; > > - pcpu = vmalloc(sizeof(void __percpu *) * 35000); > + pcpu = vmalloc(sizeof(void __percpu *) * nr_pcpu_objects); Could have used vmalloc_array() here. Otherwise lgtm, thanks.
