The patch titled
Subject: hugetlb: remove check_coalesce_bug debug code
has been added to the -mm tree. Its filename is
hugetlb-support-file_region-coalescing-again-fix-2.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/hugetlb-support-file_region-coalescing-again-fix-2.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/hugetlb-support-file_region-coalescing-again-fix-2.patch
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------------------------------------------------------
From: Mina Almasry <almasrymina@xxxxxxxxxx>
Subject: hugetlb: remove check_coalesce_bug debug code
Commit b5f16a533ce8a ("hugetlb: support file_region coalescing again")
made changes to the resv_map code which are hard to test, it so added
debug code guarded by CONFIG_DEBUG_VM which conducts an expensive
operation that loops over the resv_map and checks it for errors.
Unfortunately, some distros have CONFIG_DEBUG_VM on in their default
kernels, and we don't want this debug code behind CONFIG_DEBUG_VM and
called each time a file region is added. This patch removes this debug
code. I may look into making it a test or leave it for my local testing.
Link: http://lkml.kernel.org/r/20200219233610.13808-1-almasrymina@xxxxxxxxxx
Fixes: b5f16a533ce8a ("hugetlb: support file_region coalescing again")
Signed-off-by: Mina Almasry <almasrymina@xxxxxxxxxx>
Reviewed-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Shakeel Butt <shakeelb@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/hugetlb.c | 43 -------------------------------------------
1 file changed, 43 deletions(-)
--- a/mm/hugetlb.c~hugetlb-support-file_region-coalescing-again-fix-2
+++ a/mm/hugetlb.c
@@ -289,48 +289,6 @@ static bool has_same_uncharge_info(struc
#endif
}
-#if defined(CONFIG_DEBUG_VM) && defined(CONFIG_CGROUP_HUGETLB)
-static void dump_resv_map(struct resv_map *resv)
-{
- struct list_head *head = &resv->regions;
- struct file_region *rg = NULL;
-
- pr_err("--------- start print resv_map ---------\n");
- list_for_each_entry(rg, head, link) {
- pr_err("rg->from=%ld, rg->to=%ld, rg->reservation_counter=%px, rg->css=%px\n",
- rg->from, rg->to, rg->reservation_counter, rg->css);
- }
- pr_err("--------- end print resv_map ---------\n");
-}
-
-/* Debug function to loop over the resv_map and make sure that coalescing is
- * working.
- */
-static void check_coalesce_bug(struct resv_map *resv)
-{
- struct list_head *head = &resv->regions;
- struct file_region *rg = NULL, *nrg = NULL;
-
- list_for_each_entry(rg, head, link) {
- nrg = list_next_entry(rg, link);
-
- if (&nrg->link == head)
- break;
-
- if (nrg->reservation_counter && nrg->from == rg->to &&
- nrg->reservation_counter == rg->reservation_counter &&
- nrg->css == rg->css) {
- dump_resv_map(resv);
- VM_BUG_ON(true);
- }
- }
-}
-#else
-static void check_coalesce_bug(struct resv_map *resv)
-{
-}
-#endif
-
static void coalesce_file_region(struct resv_map *resv, struct file_region *rg)
{
struct file_region *nrg = NULL, *prg = NULL;
@@ -435,7 +393,6 @@ static long add_reservation_in_range(str
}
VM_BUG_ON(add < 0);
- check_coalesce_bug(resv);
return add;
}
_
Patches currently in -mm which might be from almasrymina@xxxxxxxxxx are
hugetlb_cgroup-add-hugetlb_cgroup-reservation-counter.patch
hugetlb_cgroup-add-interface-for-charge-uncharge-hugetlb-reservations.patch
mm-hugetlb_cgroup-fix-hugetlb_cgroup-migration.patch
hugetlb_cgroup-add-reservation-accounting-for-private-mappings.patch
hugetlb-disable-region_add-file_region-coalescing.patch
hugetlb-disable-region_add-file_region-coalescing-fix.patch
hugetlb_cgroup-add-accounting-for-shared-mappings.patch
hugetlb_cgroup-support-noreserve-mappings.patch
hugetlb-support-file_region-coalescing-again.patch
hugetlb-support-file_region-coalescing-again-fix.patch
hugetlb-support-file_region-coalescing-again-fix-2.patch
hugetlb_cgroup-add-hugetlb_cgroup-reservation-tests.patch
hugetlb_cgroup-add-hugetlb_cgroup-reservation-docs.patch
