Commit 996ff7a0 authored by Jane Chu's avatar Jane Chu Committed by Linus Torvalds
Browse files

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@oracle.com


Signed-off-by: default avatarJane Chu <jane.chu@oracle.com>
Reviewed-by: default avatarDan Williams <dan.j.williams@intel.com>
Acked-by: default avatarNaoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 2e53c4e1

mm/memory-failure.c

+13 −27
Original line number Diff line number Diff line
@@ -303,25 +303,19 @@ static unsigned long dev_pagemap_mapping_shift(struct page *page, 
/*

 * 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->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_struct *tsk, struct page *p, 
		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_kill(struct task_struct *tsk, 
 * 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 page *page, struct list_head *to_kill, 
			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 page *page, struct list_head *to_kill, 
 * 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 page *page, struct list_head *to_kill, 
			 * 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 page *page, struct list_head *to_kill, 


/*

 * 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[] = {

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