The patch titled
Subject: selftests: cgroup: fix alloc_anon_noexit() instantly freeing memory
has been added to the -mm tree. Its filename is
selftests-cgroup-fix-alloc_anon_noexit-instantly-freeing-memory.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/selftests-cgroup-fix-alloc_anon_noexit-instantly-freeing-memory.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/selftests-cgroup-fix-alloc_anon_noexit-instantly-freeing-memory.patch
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------------------------------------------------------
From: Yosry Ahmed <yosryahmed@xxxxxxxxxx>
Subject: selftests: cgroup: fix alloc_anon_noexit() instantly freeing memory
Currently, alloc_anon_noexit() calls alloc_anon() which instantly frees
the allocated memory. alloc_anon_noexit() is usually used with
cg_run_nowait() to run a process in the background that allocates
memory. It makes sense for the background process to keep the memory
allocated and not instantly free it (otherwise there is no point of
running it in the background).
Link: https://lkml.kernel.org/r/20220425190040.2475377-4-yosryahmed@xxxxxxxxxx
Signed-off-by: Yosry Ahmed <yosryahmed@xxxxxxxxxx>
Acked-by: Roman Gushchin <roman.gushchin@xxxxxxxxx>
Acked-by: Shakeel Butt <shakeelb@xxxxxxxxxx>
Acked-by: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Chen Wandun <chenwandun@xxxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: Greg Thelen <gthelen@xxxxxxxxxx>
Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Jonathan Corbet <corbet@xxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: "Michal Koutn" <mkoutny@xxxxxxxx>
Cc: Shuah Khan <shuah@xxxxxxxxxx>
Cc: Tejun Heo <tj@xxxxxxxxxx>
Cc: Tim Chen <tim.c.chen@xxxxxxxxxxxxxxx>
Cc: Vaibhav Jain <vaibhav@xxxxxxxxxxxxx>
Cc: Wei Xu <weixugc@xxxxxxxxxx>
Cc: Yu Zhao <yuzhao@xxxxxxxxxx>
Cc: Zefan Li <lizefan.x@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
tools/testing/selftests/cgroup/test_memcontrol.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
--- a/tools/testing/selftests/cgroup/test_memcontrol.c~selftests-cgroup-fix-alloc_anon_noexit-instantly-freeing-memory
+++ a/tools/testing/selftests/cgroup/test_memcontrol.c
@@ -214,13 +214,17 @@ static int alloc_pagecache_50M_noexit(co
static int alloc_anon_noexit(const char *cgroup, void *arg)
{
int ppid = getppid();
+ size_t size = (unsigned long)arg;
+ char *buf, *ptr;
- if (alloc_anon(cgroup, arg))
- return -1;
+ buf = malloc(size);
+ for (ptr = buf; ptr < buf + size; ptr += PAGE_SIZE)
+ *ptr = 0;
while (getppid() == ppid)
sleep(1);
+ free(buf);
return 0;
}
_
Patches currently in -mm which might be from yosryahmed@xxxxxxxxxx are
selftests-cgroup-return-errno-from-cg_read-cg_write-on-failure.patch
selftests-cgroup-fix-alloc_anon_noexit-instantly-freeing-memory.patch
selftests-cgroup-add-a-selftest-for-memoryreclaim.patch
