The patch titled
Subject: mm/vmap: add DEBUG_AUGMENT_LOWEST_MATCH_CHECK macro
has been added to the -mm tree. Its filename is
mm-vmap-add-debug_augment_lowest_match_check-macro.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-vmap-add-debug_augment_lowest_match_check-macro.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-vmap-add-debug_augment_lowest_match_check-macro.patch
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------------------------------------------------------
From: "Uladzislau Rezki (Sony)" <urezki@xxxxxxxxx>
Subject: mm/vmap: add DEBUG_AUGMENT_LOWEST_MATCH_CHECK macro
This macro adds some debug code to check that vmap allocations are
happened in ascending order.
By default this option is set to 0 and not active. It requires
recompilation of the kernel to activate it. Set to 1, compile the kernel.
Link: http://lkml.kernel.org/r/20190402162531.10888-4-urezki@xxxxxxxxx
Signed-off-by: Uladzislau Rezki (Sony) <urezki@xxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxx>
Cc: Joel Fernandes <joelaf@xxxxxxxxxx>
Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: Oleksiy Avramchenko <oleksiy.avramchenko@xxxxxxxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Tejun Heo <tj@xxxxxxxxxx>
Cc: Thomas Garnier <thgarnie@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/vmalloc.c | 43 +++++++++++++++++++++++++++++++++++++++++++
1 file changed, 43 insertions(+)
--- a/mm/vmalloc.c~mm-vmap-add-debug_augment_lowest_match_check-macro
+++ a/mm/vmalloc.c
@@ -323,6 +323,7 @@ EXPORT_SYMBOL(vmalloc_to_pfn);
/*** Global kva allocator ***/
#define DEBUG_AUGMENT_PROPAGATE_CHECK 0
+#define DEBUG_AUGMENT_LOWEST_MATCH_CHECK 0
#define VM_LAZY_FREE 0x02
#define VM_VM_AREA 0x04
@@ -844,6 +845,44 @@ __find_vmap_lowest_match(unsigned long s
return NULL;
}
+#if DEBUG_AUGMENT_LOWEST_MATCH_CHECK
+#include <linux/random.h>
+
+static struct vmap_area *
+__find_vmap_lowest_linear_match(unsigned long size,
+ unsigned long align, unsigned long vstart)
+{
+ struct vmap_area *va;
+
+ list_for_each_entry(va, &free_vmap_area_list, list) {
+ if (!is_within_this_va(va, size, align, vstart))
+ continue;
+
+ return va;
+ }
+
+ return NULL;
+}
+
+static void
+__find_vmap_lowest_match_check(unsigned long size)
+{
+ struct vmap_area *va_1, *va_2;
+ unsigned long vstart;
+ unsigned int rnd;
+
+ get_random_bytes(&rnd, sizeof(rnd));
+ vstart = VMALLOC_START + rnd;
+
+ va_1 = __find_vmap_lowest_match(size, 1, vstart);
+ va_2 = __find_vmap_lowest_linear_match(size, 1, vstart);
+
+ if (va_1 != va_2)
+ pr_emerg("not lowest: t: 0x%p, l: 0x%p, v: 0x%lx\n",
+ va_1, va_2, vstart);
+}
+#endif
+
enum alloc_fit_type {
NOTHING_FIT = 0,
FL_FIT_TYPE = 1, /* full fit */
@@ -985,6 +1024,10 @@ __alloc_vmap_area(unsigned long size, un
if (ret)
return vend;
+#if DEBUG_AUGMENT_LOWEST_MATCH_CHECK
+ __find_vmap_lowest_match_check(size);
+#endif
+
return nva_start_addr;
}
_
Patches currently in -mm which might be from urezki@xxxxxxxxx are
mm-add-priority-threshold-to-__purge_vmap_area_lazy.patch
mm-vmap-keep-track-of-free-blocks-for-vmap-allocation.patch
mm-vmap-keep-track-of-free-blocks-for-vmap-allocation-v3.patch
mm-vmap-add-debug_augment_propagate_check-macro.patch
mm-vmap-add-debug_augment_lowest_match_check-macro.patch
mm-vmalloc-convert-vmap_lazy_nr-to-atomic_long_t.patch
