From: Charan Teja Kalla <quic_charante@xxxxxxxxxxx> The process_mrelease() system call[1] is used to release the memory of a dying process from the context of the caller, which is similar to and uses the functions of the oom reaper logic. There exists trace logs for a process when reaped by the oom reaper. Just extend the same to when done by the process_mrelease() system call. [1] https://lore.kernel.org/linux-mm/20210809185259.405936-1-surenb@xxxxxxxxxx/ Signed-off-by: Charan Teja Kalla <quic_charante@xxxxxxxxxxx> Signed-off-by: Pratyush Brahma <quic_pbrahma@xxxxxxxxxxx> --- Changes in v2: - Added trace_skip_task_reaping() to cover more cases where we skip reaping. - Print debug information in pr_debug instead of pr_info - The original author email domain has changed. Update the new email address. [v1] https://patchwork.kernel.org/project/linux-mm/patch/1629106756-20874-1-git-send-email-charante@xxxxxxxxxxxxxx/ mm/oom_kill.c | 24 ++++++++++++++++++++---- 1 file changed, 20 insertions(+), 4 deletions(-) diff --git a/mm/oom_kill.c b/mm/oom_kill.c index 3c6cf9e3cd66..51ad5f0b612e 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -995,7 +995,6 @@ static void __oom_kill_process(struct task_struct *victim, const char *message) mmdrop(mm); put_task_struct(victim); } -#undef K /* * Kill provided task unless it's secured by setting @@ -1241,17 +1240,33 @@ SYSCALL_DEFINE2(process_mrelease, int, pidfd, unsigned int, flags) goto drop_mm; if (mmap_read_lock_killable(mm)) { + trace_skip_task_reaping(task->pid); ret = -EINTR; - goto drop_mm; + goto read_unlock; } /* * Check MMF_OOM_SKIP again under mmap_read_lock protection to ensure * possible change in exit_mmap is seen */ - if (!test_bit(MMF_OOM_SKIP, &mm->flags) && !__oom_reap_task_mm(mm)) + if (test_bit(MMF_OOM_SKIP, &mm->flags)) { + trace_skip_task_reaping(task->pid); + goto read_unlock; + } + + trace_start_task_reaping(task->pid); + + if (!__oom_reap_task_mm(mm)) ret = -EAGAIN; - mmap_read_unlock(mm); + pr_debug("process_mrelease: reaped process %d (%s), now anon-rss:%lukB, file-rss:%lukB, shmem-rss:%lukB\n", + task_pid_nr(task), task->comm, + K(get_mm_counter(mm, MM_ANONPAGES)), + K(get_mm_counter(mm, MM_FILEPAGES)), + K(get_mm_counter(mm, MM_SHMEMPAGES))); + trace_finish_task_reaping(task->pid); + +read_unlock: + mmap_read_unlock(mm); drop_mm: mmdrop(mm); put_task: @@ -1261,3 +1276,4 @@ SYSCALL_DEFINE2(process_mrelease, int, pidfd, unsigned int, flags) return -ENOSYS; #endif /* CONFIG_MMU */ } +#undef K -- 2.17.1
