The patch titled
Subject: ia64: perfmon: don't mark buffer pages as PG_reserved
has been added to the -mm tree. Its filename is
ia64-perfmon-dont-mark-buffer-pages-as-pg_reserved.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/ia64-perfmon-dont-mark-buffer-pages-as-pg_reserved.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/ia64-perfmon-dont-mark-buffer-pages-as-pg_reserved.patch
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------------------------------------------------------
From: David Hildenbrand <david@xxxxxxxxxx>
Subject: ia64: perfmon: don't mark buffer pages as PG_reserved
In the old days, remap_pfn_range() required pages to be marked as
PG_reserved, so they would e.g. never get swapped out. This was required
for special mappings. Nowadays, this is fully handled via the VMA (VM_IO
| VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP inside remap_pfn_range() to be
precise). PG_reserved is no longer required but only a relict from the
past.
So only architecture specific MM handling might require it (e.g. to
detect them as MMIO pages). As there are no architecture specific checks
for PageReserved() apart from MCA handling in ia64code, this can go. Use
simple vzalloc()/vfree() instead.
Note that before calling vzalloc(), size has already been aligned to
PAGE_SIZE, no need to align again.
Link: http://lkml.kernel.org/r/20190114125903.24845-9-david@xxxxxxxxxx
Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
Cc: Tony Luck <tony.luck@xxxxxxxxx>
Cc: Fenghua Yu <fenghua.yu@xxxxxxxxx>
Cc: Oleg Nesterov <oleg@xxxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: David Howells <dhowells@xxxxxxxxxx>
Cc: Mike Rapoport <rppt@xxxxxxxxxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/ia64/kernel/perfmon.c | 59 ++---------------------------------
1 file changed, 4 insertions(+), 55 deletions(-)
--- a/arch/ia64/kernel/perfmon.c~ia64-perfmon-dont-mark-buffer-pages-as-pg_reserved
+++ a/arch/ia64/kernel/perfmon.c
@@ -583,17 +583,6 @@ pfm_put_task(struct task_struct *task)
if (task != current) put_task_struct(task);
}
-static inline void
-pfm_reserve_page(unsigned long a)
-{
- SetPageReserved(vmalloc_to_page((void *)a));
-}
-static inline void
-pfm_unreserve_page(unsigned long a)
-{
- ClearPageReserved(vmalloc_to_page((void*)a));
-}
-
static inline unsigned long
pfm_protect_ctx_ctxsw(pfm_context_t *x)
{
@@ -816,44 +805,6 @@ pfm_reset_msgq(pfm_context_t *ctx)
DPRINT(("ctx=%p msgq reset\n", ctx));
}
-static void *
-pfm_rvmalloc(unsigned long size)
-{
- void *mem;
- unsigned long addr;
-
- size = PAGE_ALIGN(size);
- mem = vzalloc(size);
- if (mem) {
- //printk("perfmon: CPU%d pfm_rvmalloc(%ld)=%p\n", smp_processor_id(), size, mem);
- addr = (unsigned long)mem;
- while (size > 0) {
- pfm_reserve_page(addr);
- addr+=PAGE_SIZE;
- size-=PAGE_SIZE;
- }
- }
- return mem;
-}
-
-static void
-pfm_rvfree(void *mem, unsigned long size)
-{
- unsigned long addr;
-
- if (mem) {
- DPRINT(("freeing physical buffer @%p size=%lu\n", mem, size));
- addr = (unsigned long) mem;
- while ((long) size > 0) {
- pfm_unreserve_page(addr);
- addr+=PAGE_SIZE;
- size-=PAGE_SIZE;
- }
- vfree(mem);
- }
- return;
-}
-
static pfm_context_t *
pfm_context_alloc(int ctx_flags)
{
@@ -1498,7 +1449,7 @@ pfm_free_smpl_buffer(pfm_context_t *ctx)
/*
* free the buffer
*/
- pfm_rvfree(ctx->ctx_smpl_hdr, ctx->ctx_smpl_size);
+ vfree(ctx->ctx_smpl_hdr);
ctx->ctx_smpl_hdr = NULL;
ctx->ctx_smpl_size = 0UL;
@@ -2137,7 +2088,7 @@ doit:
* All memory free operations (especially for vmalloc'ed memory)
* MUST be done with interrupts ENABLED.
*/
- if (smpl_buf_addr) pfm_rvfree(smpl_buf_addr, smpl_buf_size);
+ vfree(smpl_buf_addr);
/*
* return the memory used by the context
@@ -2266,10 +2217,8 @@ pfm_smpl_buffer_alloc(struct task_struct
/*
* We do the easy to undo allocations first.
- *
- * pfm_rvmalloc(), clears the buffer, so there is no leak
*/
- smpl_buf = pfm_rvmalloc(size);
+ smpl_buf = vzalloc(size);
if (smpl_buf == NULL) {
DPRINT(("Can't allocate sampling buffer\n"));
return -ENOMEM;
@@ -2346,7 +2295,7 @@ pfm_smpl_buffer_alloc(struct task_struct
error:
vm_area_free(vma);
error_kmem:
- pfm_rvfree(smpl_buf, size);
+ vfree(smpl_buf);
return -ENOMEM;
}
_
Patches currently in -mm which might be from david@xxxxxxxxxx are
mm-balloon-update-comment-about-isolation-migration-compaction.patch
mm-convert-pg_balloon-to-pg_offline.patch
kexec-export-pg_offline-to-vmcoreinfo.patch
xen-balloon-mark-inflated-pages-pg_offline.patch
hv_balloon-mark-inflated-pages-pg_offline.patch
vmw_balloon-mark-inflated-pages-pg_offline.patch
vmw_balloon-mark-inflated-pages-pg_offline-v2.patch
pm-hibernate-use-pfn_to_online_page.patch
pm-hibernate-exclude-all-pageoffline-pages.patch
pm-hibernate-exclude-all-pageoffline-pages-v2.patch
agp-efficeon-no-need-to-set-pg_reserved-on-gatt-tables.patch
s390-vdso-dont-clear-pg_reserved.patch
powerpc-vdso-dont-clear-pg_reserved.patch
riscv-vdso-dont-clear-pg_reserved.patch
m68k-mm-use-__clearpagereserved.patch
arm64-kexec-no-need-to-clearpagereserved.patch
arm64-kdump-no-need-to-mark-crashkernel-pages-manually-pg_reserved.patch
ia64-perfmon-dont-mark-buffer-pages-as-pg_reserved.patch
mm-better-document-pg_reserved.patch
