The patch titled
Subject: mm/memory-failure.c clean up around tk pre-allocation
has been added to the -mm tree. Its filename is
mm-memory-failurec-clean-up-around-tk-pre-allocation.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-memory-failurec-clean-up-around-tk-pre-allocation.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-memory-failurec-clean-up-around-tk-pre-allocation.patch
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------------------------------------------------------
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
@@ -304,25 +304,19 @@ 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);
tk->addr_valid = 1;
if (is_zone_device_page(p))
@@ -341,6 +335,7 @@ static void add_to_kill(struct task_stru
page_to_pfn(p), tsk->comm);
tk->addr_valid = 0;
}
+
get_task_struct(tsk);
tk->tsk = tsk;
list_add_tail(&tk->nd, to_kill);
@@ -432,7 +427,7 @@ 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;
@@ -457,7 +452,7 @@ 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);
@@ -468,7 +463,7 @@ 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;
@@ -492,7 +487,7 @@ 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);
@@ -501,26 +496,17 @@ 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[] = {
_
Patches currently in -mm which might be from jane.chu@xxxxxxxxxx are
mm-memory-failurec-clean-up-around-tk-pre-allocation.patch
mm-memory-failure-poison-read-receives-sigkill-instead-of-sigbus-if-mmaped-more-than-once.patch
