mm-vmalloc-properly-track-vmalloc-users.patch removed from -mm tree
The patch titled
Subject: mm, vmalloc: properly track vmalloc users
has been removed from the -mm tree. Its filename was
mm-vmalloc-properly-track-vmalloc-users.patch
This patch was dropped because it was merged into mainline or a subsystem tree
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From: Michal Hocko <[email protected]>
Subject: mm, vmalloc: properly track vmalloc users
__vmalloc_node_flags used to be static inline but this has changed by "mm:
introduce kv[mz]alloc helpers" because kvmalloc_node needs to use it as well and the code is outside of the vmalloc proper. I haven't realized that changing this will lead to a subtle bug though. The function is responsible to track the caller as well. This caller is then printed by /proc/vmallocinfo. If __vmalloc_node_flags is not inline then we would get only direct users of __vmalloc_node_flags as callers (e.g. v[mz]alloc) which reduces usefulness of this debugging feature considerably. It simply doesn't help to see that the given range belongs to vmalloc as a caller:
0xffffc90002c79000-0xffffc90002c7d000 16384 vmalloc+0x16/0x18 pages=3 vmalloc N0=3 0xffffc90002c81000-0xffffc90002c85000 16384 vmalloc+0x16/0x18 pages=3 vmalloc N1=3 0xffffc90002c8d000-0xffffc90002c91000 16384 vmalloc+0x16/0x18 pages=3 vmalloc N1=3 0xffffc90002c95000-0xffffc90002c99000 16384 vmalloc+0x16/0x18 pages=3 vmalloc N1=3
We really want to catch the _caller_ of the vmalloc function. Fix this issue by making __vmalloc_node_flags static inline again.
---
include/linux/vmalloc.h | 19 +++++++++++++++++++ mm/vmalloc.c | 12 +----------- 2 files changed, 20 insertions(+), 11 deletions(-)
include/linux/vmalloc.h renamed from include/linux/vmalloc.h~mm-vmalloc-properly-track-vmalloc-users +19 -0
@@ -6,6 +6,7 @@#include <linux/list.h> #include <linux/llist.h> #include <asm/page.h> /* pgprot_t */ +#include <asm/pgtable.h> /* PAGE_KERNEL */ #include <linux/rbtree.h> struct vm_area_struct ;/* vma defining user mapping in mm_types.h */
@@ -80,7 +81,25 @@ extern void *__vmalloc_node_range(unsign unsigned long start, unsigned long end, gfp_t gfp_mask, pgprot_t prot, unsigned long vm_flags, int node, const void *caller); +#ifndef CONFIG_MMU extern void *__vmalloc_node_flags (unsigned long size,int node,gfp_t flags); +#else +extern void *__vmalloc_node (unsigned long size,unsigned long align, +gfp_t gfp_mask,pgprot_t prot, +int node,const void *caller); + +/* +* We really want to have this inlined due to caller tracking. This +* function is used by the highlevel vmalloc apis and so we want to track +* their callers and inlining will achieve that. +*/ +static inline void *__vmalloc_node_flags (unsigned long size, +int node,gfp_t flags) +{ +return __vmalloc_node (size,1 , flags,PAGE_KERNEL , + node,__builtin_return_address (0 )); +} +#endif extern void vfree (const void *addr);extern void vfree_atomic (const void *addr);
mm/vmalloc.c renamed from mm/vmalloc.c~mm-vmalloc-properly-track-vmalloc-users +1 -10
@@ -1649,9 +1649,6 @@ void *vmap(struct page **pages, unsigned }EXPORT_SYMBOL (vmap); -static void *__vmalloc_node (unsigned long size,unsigned long align, -gfp_t gfp_mask,pgprot_t prot, -int node,const void *caller);static void *__vmalloc_area_node (struct vm_struct *area,gfp_t gfp_mask,pgprot_t prot,int node) {
@@ -1794,7 +1791,7 @@ fail:* with mm people. * */ -static void *__vmalloc_node (unsigned long size,unsigned long align, +void *__vmalloc_node (unsigned long size,unsigned long align,gfp_t gfp_mask,pgprot_t prot,int node,const void *caller) {
@@ -1809,13 +1806,6 @@ void *__vmalloc(unsigned long size, gfp_ }EXPORT_SYMBOL (__vmalloc); -void *__vmalloc_node_flags (unsigned long size, -int node,gfp_t flags) -{ -return __vmalloc_node (size,1 , flags,PAGE_KERNEL , - node,__builtin_return_address (0 )); -}