selftests/mm: read memory information without popen

read_memory_info() invokes two shell pipelines to obtain MemFree and
Hugepagesize from /proc/meminfo.  It does not check whether popen()
returns NULL before passing the result to fgets(), and it does not call
pclose() when fgets() fails.

Open /proc/meminfo directly and obtain both values in a single pass.  This
removes the unchecked NULL path, closes the file on all paths, and avoids
dependencies on external commands.

The compaction test continues to pass after this change.

Link: https://lore.kernel.org/1785845818-3131-1-git-send-email-warren.xiong@ugreen.com
Signed-off-by: Warren Xiong <warren.xiong@ugreen.com>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

0 files changed, 0 insertions, 0 deletions