The patch titled Subject: proc, oom_adj: extract oom_score_adj setting into a helper has been added to the -mm tree. Its filename is proc-oom_adj-extract-oom_score_adj-setting-into-a-helper.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/proc-oom_adj-extract-oom_score_adj-setting-into-a-helper.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/proc-oom_adj-extract-oom_score_adj-setting-into-a-helper.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/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Michal Hocko <mhocko@xxxxxxxx> Subject: proc, oom_adj: extract oom_score_adj setting into a helper Currently we have two proc interfaces to set oom_score_adj. The legacy /proc/<pid>/oom_adj and /proc/<pid>/oom_score_adj which both have their specific handlers. Big part of the logic is duplicated so extract the common code into __set_oom_adj helper. Legacy knob still expects some details slightly different so make sure those are handled same way - e.g. the legacy mode ignores oom_score_adj_min and it warns about the usage. This patch shouldn't introduce any functional changes. Link: http://lkml.kernel.org/r/1466426628-15074-4-git-send-email-mhocko@xxxxxxxxxx Signed-off-by: Michal Hocko <mhocko@xxxxxxxx> Acked-by: Oleg Nesterov <oleg@xxxxxxxxxx> Cc: Vladimir Davydov <vdavydov@xxxxxxxxxxxxx> Cc: David Rientjes <rientjes@xxxxxxxxxx> Cc: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/proc/base.c | 94 +++++++++++++++++++++-------------------------- 1 file changed, 43 insertions(+), 51 deletions(-) diff -puN fs/proc/base.c~proc-oom_adj-extract-oom_score_adj-setting-into-a-helper fs/proc/base.c --- a/fs/proc/base.c~proc-oom_adj-extract-oom_score_adj-setting-into-a-helper +++ a/fs/proc/base.c @@ -1037,7 +1037,47 @@ static ssize_t oom_adj_read(struct file return simple_read_from_buffer(buf, count, ppos, buffer, len); } -static DEFINE_MUTEX(oom_adj_mutex); +static int __set_oom_adj(struct file *file, int oom_adj, bool legacy) +{ + static DEFINE_MUTEX(oom_adj_mutex); + struct task_struct *task; + int err = 0; + + task = get_proc_task(file_inode(file)); + if (!task) + return -ESRCH; + + mutex_lock(&oom_adj_mutex); + if (legacy) { + if (oom_adj < task->signal->oom_score_adj && + !capable(CAP_SYS_RESOURCE)) { + err = -EACCES; + goto err_unlock; + } + /* + * /proc/pid/oom_adj is provided for legacy purposes, ask users to use + * /proc/pid/oom_score_adj instead. + */ + pr_warn_once("%s (%d): /proc/%d/oom_adj is deprecated, please use /proc/%d/oom_score_adj instead.\n", + current->comm, task_pid_nr(current), task_pid_nr(task), + task_pid_nr(task)); + } else { + if ((short)oom_adj < task->signal->oom_score_adj_min && + !capable(CAP_SYS_RESOURCE)) { + err = -EACCES; + goto err_unlock; + } + } + + task->signal->oom_score_adj = oom_adj; + if (!legacy && has_capability_noaudit(current, CAP_SYS_RESOURCE)) + task->signal->oom_score_adj_min = (short)oom_adj; + trace_oom_score_adj_update(task); +err_unlock: + mutex_unlock(&oom_adj_mutex); + put_task_struct(task); + return err; +} /* * /proc/pid/oom_adj exists solely for backwards compatibility with previous @@ -1052,7 +1092,6 @@ static DEFINE_MUTEX(oom_adj_mutex); static ssize_t oom_adj_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) { - struct task_struct *task; char buffer[PROC_NUMBUF]; int oom_adj; int err; @@ -1074,12 +1113,6 @@ static ssize_t oom_adj_write(struct file goto out; } - task = get_proc_task(file_inode(file)); - if (!task) { - err = -ESRCH; - goto out; - } - /* * Scale /proc/pid/oom_score_adj appropriately ensuring that a maximum * value is always attainable. @@ -1089,26 +1122,7 @@ static ssize_t oom_adj_write(struct file else oom_adj = (oom_adj * OOM_SCORE_ADJ_MAX) / -OOM_DISABLE; - mutex_lock(&oom_adj_mutex); - if (oom_adj < task->signal->oom_score_adj && - !capable(CAP_SYS_RESOURCE)) { - err = -EACCES; - goto err_unlock; - } - - /* - * /proc/pid/oom_adj is provided for legacy purposes, ask users to use - * /proc/pid/oom_score_adj instead. - */ - pr_warn_once("%s (%d): /proc/%d/oom_adj is deprecated, please use /proc/%d/oom_score_adj instead.\n", - current->comm, task_pid_nr(current), task_pid_nr(task), - task_pid_nr(task)); - - task->signal->oom_score_adj = oom_adj; - trace_oom_score_adj_update(task); -err_unlock: - mutex_unlock(&oom_adj_mutex); - put_task_struct(task); + err = __set_oom_adj(file, oom_adj, true); out: return err < 0 ? err : count; } @@ -1138,7 +1152,6 @@ static ssize_t oom_score_adj_read(struct static ssize_t oom_score_adj_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) { - struct task_struct *task; char buffer[PROC_NUMBUF]; int oom_score_adj; int err; @@ -1160,28 +1173,7 @@ static ssize_t oom_score_adj_write(struc goto out; } - task = get_proc_task(file_inode(file)); - if (!task) { - err = -ESRCH; - goto out; - } - - mutex_lock(&oom_adj_mutex); - if ((short)oom_score_adj < task->signal->oom_score_adj_min && - !capable(CAP_SYS_RESOURCE)) { - err = -EACCES; - goto err_unlock; - } - - task->signal->oom_score_adj = (short)oom_score_adj; - if (has_capability_noaudit(current, CAP_SYS_RESOURCE)) - task->signal->oom_score_adj_min = (short)oom_score_adj; - - trace_oom_score_adj_update(task); - -err_unlock: - mutex_unlock(&oom_adj_mutex); - put_task_struct(task); + err = __set_oom_adj(file, oom_score_adj, false); out: return err < 0 ? err : count; } _ Patches currently in -mm which might be from mhocko@xxxxxxxx are tree-wide-get-rid-of-__gfp_repeat-for-order-0-allocations-part-i.patch x86-get-rid-of-superfluous-__gfp_repeat.patch x86-efi-get-rid-of-superfluous-__gfp_repeat.patch arm64-get-rid-of-superfluous-__gfp_repeat.patch arc-get-rid-of-superfluous-__gfp_repeat.patch mips-get-rid-of-superfluous-__gfp_repeat.patch nios2-get-rid-of-superfluous-__gfp_repeat.patch parisc-get-rid-of-superfluous-__gfp_repeat.patch score-get-rid-of-superfluous-__gfp_repeat.patch powerpc-get-rid-of-superfluous-__gfp_repeat.patch sparc-get-rid-of-superfluous-__gfp_repeat.patch s390-get-rid-of-superfluous-__gfp_repeat.patch sh-get-rid-of-superfluous-__gfp_repeat.patch tile-get-rid-of-superfluous-__gfp_repeat.patch unicore32-get-rid-of-superfluous-__gfp_repeat.patch jbd2-get-rid-of-superfluous-__gfp_repeat.patch arm-get-rid-of-superfluous-__gfp_repeat.patch slab-make-gfp_slab_bug_mask-information-more-human-readable.patch slab-do-not-panic-on-invalid-gfp_mask.patch mm-oom_reaper-make-sure-that-mmput_async-is-called-only-when-memory-was-reaped.patch mm-memcg-use-consistent-gfp-flags-during-readahead.patch mm-memcg-use-consistent-gfp-flags-during-readahead-fix.patch proc-oom-drop-bogus-task_lock-and-mm-check.patch proc-oom-drop-bogus-sighand-lock.patch proc-oom_adj-extract-oom_score_adj-setting-into-a-helper.patch mm-oom_adj-make-sure-processes-sharing-mm-have-same-view-of-oom_score_adj.patch mm-oom-skip-vforked-tasks-from-being-selected.patch mm-oom-kill-all-tasks-sharing-the-mm.patch mm-oom-fortify-task_will_free_mem.patch mm-oom-task_will_free_mem-should-skip-oom_reaped-tasks.patch mm-oom_reaper-do-not-attempt-to-reap-a-task-more-than-twice.patch mm-oom-hide-mm-which-is-shared-with-kthread-or-global-init.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html