The patch titled Subject: selftests/vm/transhuge-stress: fix ram size thinko has been added to the -mm tree. Its filename is selftests-vm-transhuge-stress-fix-ram-size-thinko.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/selftests-vm-transhuge-stress-fix-ram-size-thinko.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/selftests-vm-transhuge-stress-fix-ram-size-thinko.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: "George G. Davis" <davis.george@xxxxxxxxxxx> Subject: selftests/vm/transhuge-stress: fix ram size thinko When executing transhuge-stress with an argument to specify the virtual memory size for testing, the ram size is reported as 0, e.g. transhuge-stress 384 thp-mmap: allocate 192 transhuge pages, using 384 MiB virtual memory and 0 MiB of ram thp-mmap: 0.184 s/loop, 0.957 ms/page, 2090.265 MiB/s 192 succeed, 0 failed This appears to be due to a thinko in commit 0085d61fe05e ("selftests/vm/transhuge-stress: stress test for memory compaction"), where, at a guess, the intent was to base "xyz MiB of ram" on `ram` size. Here are results after using `ram` size: thp-mmap: allocate 192 transhuge pages, using 384 MiB virtual memory and 14 MiB of ram Link: https://lkml.kernel.org/r/20210825135843.29052-1-george_davis@xxxxxxxxxx Fixes: 0085d61fe05e ("selftests/vm/transhuge-stress: stress test for memory compaction") Signed-off-by: George G. Davis <davis.george@xxxxxxxxxxx> Cc: Konstantin Khlebnikov <koct9i@xxxxxxxxx> Cc: Eugeniu Rosca <erosca@xxxxxxxxxxxxxx> Cc: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- tools/testing/selftests/vm/transhuge-stress.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/tools/testing/selftests/vm/transhuge-stress.c~selftests-vm-transhuge-stress-fix-ram-size-thinko +++ a/tools/testing/selftests/vm/transhuge-stress.c @@ -79,7 +79,7 @@ int main(int argc, char **argv) warnx("allocate %zd transhuge pages, using %zd MiB virtual memory" " and %zd MiB of ram", len >> HPAGE_SHIFT, len >> 20, - len >> (20 + HPAGE_SHIFT - PAGE_SHIFT - 1)); + ram >> (20 + HPAGE_SHIFT - PAGE_SHIFT - 1)); pagemap_fd = open("/proc/self/pagemap", O_RDONLY); if (pagemap_fd < 0) _ Patches currently in -mm which might be from davis.george@xxxxxxxxxxx are selftests-vm-transhuge-stress-fix-ram-size-thinko.patch