From: Jane Chu <jane.chu@xxxxxxxxxx> Subject: mm/memory-failure.c clean up around tk pre-allocation add_to_kill() expects the first 'tk' to be pre-allocated, it makes subsequent allocations on need basis, this makes the code a bit difficult to read. Move all the allocation internal to add_to_kill() and drop the **tk argument. Link: http://lkml.kernel.org/r/1565112345-28754-2-git-send-email-jane.chu@xxxxxxxxxx Signed-off-by: Jane Chu <jane.chu@xxxxxxxxxx> Reviewed-by: Dan Williams <dan.j.williams@xxxxxxxxx> Acked-by: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/memory-failure.c | 40 +++++++++++++--------------------------- 1 file changed, 13 insertions(+), 27 deletions(-) --- a/mm/memory-failure.c~mm-memory-failurec-clean-up-around-tk-pre-allocation +++ a/mm/memory-failure.c @@ -303,25 +303,19 @@ static unsigned long dev_pagemap_mapping /* * Schedule a process for later kill. * Uses GFP_ATOMIC allocations to avoid potential recursions in the VM. - * TBD would GFP_NOIO be enough? */ static void add_to_kill(struct task_struct *tsk, struct page *p, struct vm_area_struct *vma, - struct list_head *to_kill, - struct to_kill **tkc) + struct list_head *to_kill) { struct to_kill *tk; - if (*tkc) { - tk = *tkc; - *tkc = NULL; - } else { - tk = kmalloc(sizeof(struct to_kill), GFP_ATOMIC); - if (!tk) { - pr_err("Memory failure: Out of memory while machine check handling\n"); - return; - } + tk = kmalloc(sizeof(struct to_kill), GFP_ATOMIC); + if (!tk) { + pr_err("Memory failure: Out of memory while machine check handling\n"); + return; } + tk->addr = page_address_in_vma(p, vma); if (is_zone_device_page(p)) tk->size_shift = dev_pagemap_mapping_shift(p, vma); @@ -345,6 +339,7 @@ static void add_to_kill(struct task_stru kfree(tk); return; } + get_task_struct(tsk); tk->tsk = tsk; list_add_tail(&tk->nd, to_kill); @@ -436,7 +431,7 @@ static struct task_struct *task_early_ki * Collect processes when the error hit an anonymous page. */ static void collect_procs_anon(struct page *page, struct list_head *to_kill, - struct to_kill **tkc, int force_early) + int force_early) { struct vm_area_struct *vma; struct task_struct *tsk; @@ -461,7 +456,7 @@ static void collect_procs_anon(struct pa if (!page_mapped_in_vma(page, vma)) continue; if (vma->vm_mm == t->mm) - add_to_kill(t, page, vma, to_kill, tkc); + add_to_kill(t, page, vma, to_kill); } } read_unlock(&tasklist_lock); @@ -472,7 +467,7 @@ static void collect_procs_anon(struct pa * Collect processes when the error hit a file mapped page. */ static void collect_procs_file(struct page *page, struct list_head *to_kill, - struct to_kill **tkc, int force_early) + int force_early) { struct vm_area_struct *vma; struct task_struct *tsk; @@ -496,7 +491,7 @@ static void collect_procs_file(struct pa * to be informed of all such data corruptions. */ if (vma->vm_mm == t->mm) - add_to_kill(t, page, vma, to_kill, tkc); + add_to_kill(t, page, vma, to_kill); } } read_unlock(&tasklist_lock); @@ -505,26 +500,17 @@ static void collect_procs_file(struct pa /* * Collect the processes who have the corrupted page mapped to kill. - * This is done in two steps for locking reasons. - * First preallocate one tokill structure outside the spin locks, - * so that we can kill at least one process reasonably reliable. */ static void collect_procs(struct page *page, struct list_head *tokill, int force_early) { - struct to_kill *tk; - if (!page->mapping) return; - tk = kmalloc(sizeof(struct to_kill), GFP_NOIO); - if (!tk) - return; if (PageAnon(page)) - collect_procs_anon(page, tokill, &tk, force_early); + collect_procs_anon(page, tokill, force_early); else - collect_procs_file(page, tokill, &tk, force_early); - kfree(tk); + collect_procs_file(page, tokill, force_early); } static const char *action_name[] = { _
