diff mbox series

mm/page.c: move mem_init_print_info() to later place

Message ID 20231122043550.489889-1-bhe@redhat.com
State New
Headers
Series mm/page.c: move mem_init_print_info() to later place |

Commit Message

Baoquan He Nov. 22, 2023, 4:35 a.m. UTC 
  Currently if CONFIG_DEFERRED_STRUCT_PAGE_INIT is enabled, only part of
pages are initialized and added into buddy allocator at early stage. Then
the system memory information printed by mem_init_print_info() is
incorrect. The snippets of boot log are pasted here:
-----------------------------------------------------------------------
[    0.059606] mem auto-init: stack:all(zero), heap alloc:off, heap free:off
[    0.059622] software IO TLB: area num 64.
[    0.143887] Memory: 1767888K/133954872K available (20480K kernel code, 3284K rwdata, 8972K rodata, 4572K init, 4916K bss, 2529756K reserved, 0K cma-reserved)
[    0.145111] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=64, Nodes=2
---------------------------------------------------------------------------

Here, move mem_init_print_info() to later place until page init is
finished. After the fix, the printed memory information is like this:
-------------------------------------------------------------------------
[  +0.001002] smpboot: Total of 64 processors activated (293724.92 BogoMIPS)
[  +0.050086] node 0 deferred pages initialised in 45ms
[  +0.007309] node 1 deferred pages initialised in 53ms
[    4.035449] Memory: 131272772K/133954872K available (20480K kernel code, 3284K rwdata, 8972K rodata, 4572K init, 4916K bss, 2529700K reserved, 0K cma-reserved)
[  +0.015995] devtmpfs: initialized
[  +0.003943] x86/mm: Memory block size: 2048MB
-------------------------------------------------------------------------

Signed-off-by: Baoquan He <bhe@redhat.com>
---
 include/linux/gfp.h | 1 +
 init/main.c         | 1 +
 mm/mm_init.c        | 3 +--
 3 files changed, 3 insertions(+), 2 deletions(-)

Comments

Mike Rapoport Nov. 22, 2023, 3:08 p.m. UTC | #1 
Hi Baoquan,


On Wed, Nov 22, 2023 at 12:35:50PM +0800, Baoquan He wrote:

> Subject: [PATCH] mm/page.c: move mem_init_print_info() to later place

We don't have mm/page.c, 

> Currently if CONFIG_DEFERRED_STRUCT_PAGE_INIT is enabled, only part of
> pages are initialized and added into buddy allocator at early stage. Then
> the system memory information printed by mem_init_print_info() is
> incorrect. The snippets of boot log are pasted here:
> -----------------------------------------------------------------------
> [    0.059606] mem auto-init: stack:all(zero), heap alloc:off, heap free:off
> [    0.059622] software IO TLB: area num 64.
> [    0.143887] Memory: 1767888K/133954872K available (20480K kernel code, 3284K rwdata, 8972K rodata, 4572K init, 4916K bss, 2529756K reserved, 0K cma-reserved)
> [    0.145111] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=64, Nodes=2
> ---------------------------------------------------------------------------

At this point only the pages that were initialized and free are available.
The message does not reflect that large part of memory is still not initialized,
but it's not wrong.

> Here, move mem_init_print_info() to later place until page init is
> finished. After the fix, the printed memory information is like this:
> -------------------------------------------------------------------------
> [  +0.001002] smpboot: Total of 64 processors activated (293724.92 BogoMIPS)
> [  +0.050086] node 0 deferred pages initialised in 45ms
> [  +0.007309] node 1 deferred pages initialised in 53ms
> [    4.035449] Memory: 131272772K/133954872K available (20480K kernel code, 3284K rwdata, 8972K rodata, 4572K init, 4916K bss, 2529700K reserved, 0K cma-reserved)
> [  +0.015995] devtmpfs: initialized
> [  +0.003943] x86/mm: Memory block size: 2048MB
> -------------------------------------------------------------------------

If we print this message that late, some of the memory will be allocated
from buddy and it maybe confusing.

I suggest to print how much memory is not yet initialized and leave
mem_init_print_info() where it is now.
 
> Signed-off-by: Baoquan He <bhe@redhat.com>
> ---
>  include/linux/gfp.h | 1 +
>  init/main.c         | 1 +
>  mm/mm_init.c        | 3 +--
>  3 files changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/include/linux/gfp.h b/include/linux/gfp.h
> index de292a007138..2d69fa59b489 100644
> --- a/include/linux/gfp.h
> +++ b/include/linux/gfp.h
> @@ -335,6 +335,7 @@ void drain_local_pages(struct zone *zone);
>  
>  void page_alloc_init_late(void);
>  void setup_pcp_cacheinfo(void);
> +void mem_init_print_info(void);
>  
>  /*
>   * gfp_allowed_mask is set to GFP_BOOT_MASK during early boot to restrict what
> diff --git a/init/main.c b/init/main.c
> index e24b0780fdff..88f238a478a1 100644
> --- a/init/main.c
> +++ b/init/main.c
> @@ -1547,6 +1547,7 @@ static noinline void __init kernel_init_freeable(void)
>  	workqueue_init_topology();
>  	padata_init();
>  	page_alloc_init_late();
> +	mem_init_print_info();
  
No need to make mem_init_print_info() global and call it from main.c, you
can call it from page_alloc_init_late().

>  	do_basic_setup();
>  
> diff --git a/mm/mm_init.c b/mm/mm_init.c
> index 077bfe393b5e..d08f7c7f75f1 100644
> --- a/mm/mm_init.c
> +++ b/mm/mm_init.c
> @@ -2703,7 +2703,7 @@ static void __init report_meminit(void)
>  		pr_info("mem auto-init: clearing system memory may take some time...\n");
>  }
>  
> -static void __init mem_init_print_info(void)
> +void __init mem_init_print_info(void)
>  {
>  	unsigned long physpages, codesize, datasize, rosize, bss_size;
>  	unsigned long init_code_size, init_data_size;
> @@ -2774,7 +2774,6 @@ void __init mm_core_init(void)
>  	kmsan_init_shadow();
>  	stack_depot_early_init();
>  	mem_init();
> -	mem_init_print_info();
>  	kmem_cache_init();
>  	/*
>  	 * page_owner must be initialized after buddy is ready, and also after
> -- 
> 2.41.0
>
Baoquan He Nov. 24, 2023, 7:31 a.m. UTC | #2 
On 11/22/23 at 05:08pm, Mike Rapoport wrote:
> Hi Baoquan,
> 
> 
> On Wed, Nov 22, 2023 at 12:35:50PM +0800, Baoquan He wrote:
> 
> > Subject: [PATCH] mm/page.c: move mem_init_print_info() to later place
> 
> We don't have mm/page.c, 

Thanks for reviewing.

Yes, this was queued in my local branch long time ago, I forgot to
update the file name.

> 
> > Currently if CONFIG_DEFERRED_STRUCT_PAGE_INIT is enabled, only part of
> > pages are initialized and added into buddy allocator at early stage. Then
> > the system memory information printed by mem_init_print_info() is
> > incorrect. The snippets of boot log are pasted here:
> > -----------------------------------------------------------------------
> > [    0.059606] mem auto-init: stack:all(zero), heap alloc:off, heap free:off
> > [    0.059622] software IO TLB: area num 64.
> > [    0.143887] Memory: 1767888K/133954872K available (20480K kernel code, 3284K rwdata, 8972K rodata, 4572K init, 4916K bss, 2529756K reserved, 0K cma-reserved)
> > [    0.145111] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=64, Nodes=2
> > ---------------------------------------------------------------------------
> 
> At this point only the pages that were initialized and free are available.
> The message does not reflect that large part of memory is still not initialized,
> but it's not wrong.

Agree. I noticed this because I often need check the memory init and
memory size during kernel bootup. The current message gives people a
shock at first glance because it looks like a huge reserved memory
existing in system.

> 
> > Here, move mem_init_print_info() to later place until page init is
> > finished. After the fix, the printed memory information is like this:
> > -------------------------------------------------------------------------
> > [  +0.001002] smpboot: Total of 64 processors activated (293724.92 BogoMIPS)
> > [  +0.050086] node 0 deferred pages initialised in 45ms
> > [  +0.007309] node 1 deferred pages initialised in 53ms
> > [    4.035449] Memory: 131272772K/133954872K available (20480K kernel code, 3284K rwdata, 8972K rodata, 4572K init, 4916K bss, 2529700K reserved, 0K cma-reserved)
> > [  +0.015995] devtmpfs: initialized
> > [  +0.003943] x86/mm: Memory block size: 2048MB
> > -------------------------------------------------------------------------
> 
> If we print this message that late, some of the memory will be allocated
> from buddy and it maybe confusing.

that's true.

> 
> I suggest to print how much memory is not yet initialized and leave
> mem_init_print_info() where it is now.

Sounds great to me, will work out a new version as suggested.

>  
> > Signed-off-by: Baoquan He <bhe@redhat.com>
> > ---
> >  include/linux/gfp.h | 1 +
> >  init/main.c         | 1 +
> >  mm/mm_init.c        | 3 +--
> >  3 files changed, 3 insertions(+), 2 deletions(-)
> > 
> > diff --git a/include/linux/gfp.h b/include/linux/gfp.h
> > index de292a007138..2d69fa59b489 100644
> > --- a/include/linux/gfp.h
> > +++ b/include/linux/gfp.h
> > @@ -335,6 +335,7 @@ void drain_local_pages(struct zone *zone);
> >  
> >  void page_alloc_init_late(void);
> >  void setup_pcp_cacheinfo(void);
> > +void mem_init_print_info(void);
> >  
> >  /*
> >   * gfp_allowed_mask is set to GFP_BOOT_MASK during early boot to restrict what
> > diff --git a/init/main.c b/init/main.c
> > index e24b0780fdff..88f238a478a1 100644
> > --- a/init/main.c
> > +++ b/init/main.c
> > @@ -1547,6 +1547,7 @@ static noinline void __init kernel_init_freeable(void)
> >  	workqueue_init_topology();
> >  	padata_init();
> >  	page_alloc_init_late();
> > +	mem_init_print_info();
>   
> No need to make mem_init_print_info() global and call it from main.c, you
> can call it from page_alloc_init_late().

Agree, that's much better if we take that way.

> 
> >  	do_basic_setup();
> >  
> > diff --git a/mm/mm_init.c b/mm/mm_init.c
> > index 077bfe393b5e..d08f7c7f75f1 100644
> > --- a/mm/mm_init.c
> > +++ b/mm/mm_init.c
> > @@ -2703,7 +2703,7 @@ static void __init report_meminit(void)
> >  		pr_info("mem auto-init: clearing system memory may take some time...\n");
> >  }
> >  
> > -static void __init mem_init_print_info(void)
> > +void __init mem_init_print_info(void)
> >  {
> >  	unsigned long physpages, codesize, datasize, rosize, bss_size;
> >  	unsigned long init_code_size, init_data_size;
> > @@ -2774,7 +2774,6 @@ void __init mm_core_init(void)
> >  	kmsan_init_shadow();
> >  	stack_depot_early_init();
> >  	mem_init();
> > -	mem_init_print_info();
> >  	kmem_cache_init();
> >  	/*
> >  	 * page_owner must be initialized after buddy is ready, and also after
> > -- 
> > 2.41.0
> > 
> 
> -- 
> Sincerely yours,
> Mike.
>
diff mbox series

Patch

diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index de292a007138..2d69fa59b489 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -335,6 +335,7 @@  void drain_local_pages(struct zone *zone);
 
 void page_alloc_init_late(void);
 void setup_pcp_cacheinfo(void);
+void mem_init_print_info(void);
 
 /*
  * gfp_allowed_mask is set to GFP_BOOT_MASK during early boot to restrict what
diff --git a/init/main.c b/init/main.c
index e24b0780fdff..88f238a478a1 100644
--- a/init/main.c
+++ b/init/main.c
@@ -1547,6 +1547,7 @@  static noinline void __init kernel_init_freeable(void)
 	workqueue_init_topology();
 	padata_init();
 	page_alloc_init_late();
+	mem_init_print_info();
 
 	do_basic_setup();
 
diff --git a/mm/mm_init.c b/mm/mm_init.c
index 077bfe393b5e..d08f7c7f75f1 100644
--- a/mm/mm_init.c
+++ b/mm/mm_init.c
@@ -2703,7 +2703,7 @@  static void __init report_meminit(void)
 		pr_info("mem auto-init: clearing system memory may take some time...\n");
 }
 
-static void __init mem_init_print_info(void)
+void __init mem_init_print_info(void)
 {
 	unsigned long physpages, codesize, datasize, rosize, bss_size;
 	unsigned long init_code_size, init_data_size;
@@ -2774,7 +2774,6 @@  void __init mm_core_init(void)
 	kmsan_init_shadow();
 	stack_depot_early_init();
 	mem_init();
-	mem_init_print_info();
 	kmem_cache_init();
 	/*
 	 * page_owner must be initialized after buddy is ready, and also after