2020-11-10 12:24:20

by Faiyaz Mohammed

[permalink] [raw]
Subject: [PATCH] mm: memblock: add more debug logs

Exact caller of memblock_phys_alloc_range is not available with
"memblock=debug". Below information is not enough for memory accounting.
for example:
[ 0.000000] memblock_reserve: [0x000000023fc6b000-0x000000023fc6bfff] memblock_alloc_range_nid+0xc0/0x188

To enhance the memblock_dbg information or to get the exact owner of the
memblock_reserve, add debug logs in memblock_phys_alloc_range function.
After adding logs:
[ 0.000000] memblock_phys_alloc_range: 4096 bytes align=0x1000 from=0x0000000000000000 max_addr=0x0000000000000000 early_pgtable_alloc+0x24/0x178
[ 0.000000] memblock_reserve: [0x000000023fc6b000-0x000000023fc6bfff] memblock_alloc_range_nid+0xc0/0x188

Signed-off-by: Faiyaz Mohammed <[email protected]>
---
mm/memblock.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/mm/memblock.c b/mm/memblock.c
index 049df41..f65af9f 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -1419,6 +1419,9 @@ phys_addr_t __init memblock_phys_alloc_range(phys_addr_t size,
phys_addr_t start,
phys_addr_t end)
{
+ memblock_dbg("%s: %llu bytes align=0x%llx from=%pa max_addr=%pa %pS\n",
+ __func__, (u64)size, (u64)align, &start, &end,
+ (void *)_RET_IP_);
return memblock_alloc_range_nid(size, align, start, end, NUMA_NO_NODE,
false);
}
--
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a
member of the Code Aurora Forum, hosted by The Linux Foundation


2020-11-10 18:18:14

by Mike Rapoport

[permalink] [raw]
Subject: Re: [PATCH] mm: memblock: add more debug logs

Hi,

On Tue, Nov 10, 2020 at 05:49:58PM +0530, Faiyaz Mohammed wrote:
> Exact caller of memblock_phys_alloc_range is not available with
> "memblock=debug". Below information is not enough for memory accounting.
> for example:
> [ 0.000000] memblock_reserve: [0x000000023fc6b000-0x000000023fc6bfff] memblock_alloc_range_nid+0xc0/0x188
>
> To enhance the memblock_dbg information or to get the exact owner of the
> memblock_reserve, add debug logs in memblock_phys_alloc_range function.

Why would you want to use memblock=debug for memory accounting or for
tracking of the owners of the reserved memory?

> After adding logs:
> [ 0.000000] memblock_phys_alloc_range: 4096 bytes align=0x1000 from=0x0000000000000000 max_addr=0x0000000000000000 early_pgtable_alloc+0x24/0x178
> [ 0.000000] memblock_reserve: [0x000000023fc6b000-0x000000023fc6bfff] memblock_alloc_range_nid+0xc0/0x188
>
> Signed-off-by: Faiyaz Mohammed <[email protected]>
> ---
> mm/memblock.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/mm/memblock.c b/mm/memblock.c
> index 049df41..f65af9f 100644
> --- a/mm/memblock.c
> +++ b/mm/memblock.c
> @@ -1419,6 +1419,9 @@ phys_addr_t __init memblock_phys_alloc_range(phys_addr_t size,
> phys_addr_t start,
> phys_addr_t end)
> {
> + memblock_dbg("%s: %llu bytes align=0x%llx from=%pa max_addr=%pa %pS\n",
> + __func__, (u64)size, (u64)align, &start, &end,
> + (void *)_RET_IP_);
> return memblock_alloc_range_nid(size, align, start, end, NUMA_NO_NODE,
> false);
> }
> --
> QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a
> member of the Code Aurora Forum, hosted by The Linux Foundation
>

--
Sincerely yours,
Mike.

2020-11-11 08:04:44

by Faiyaz Mohammed

[permalink] [raw]
Subject: Re: [PATCH] mm: memblock: add more debug logs


On 11/10/2020 11:46 PM, Mike Rapoport wrote:
> Hi,
>
> On Tue, Nov 10, 2020 at 05:49:58PM +0530, Faiyaz Mohammed wrote:
>> Exact caller of memblock_phys_alloc_range is not available with
>> "memblock=debug". Below information is not enough for memory accounting.
>> for example:
>> [ 0.000000] memblock_reserve: [0x000000023fc6b000-0x000000023fc6bfff] memblock_alloc_range_nid+0xc0/0x188
>>
>> To enhance the memblock_dbg information or to get the exact owner of the
>> memblock_reserve, add debug logs in memblock_phys_alloc_range function.
> Why would you want to use memblock=debug for memory accounting or for
> tracking of the owners of the reserved memory?
We do memblock reserved accounting to track owners to know size of memory

allocated by different drivers/owners through memblock_reserve, which help

in comparing different kernel version and in optimizations.

>
>> After adding logs:
>> [ 0.000000] memblock_phys_alloc_range: 4096 bytes align=0x1000 from=0x0000000000000000 max_addr=0x0000000000000000 early_pgtable_alloc+0x24/0x178
>> [ 0.000000] memblock_reserve: [0x000000023fc6b000-0x000000023fc6bfff] memblock_alloc_range_nid+0xc0/0x188
>>
>> Signed-off-by: Faiyaz Mohammed <[email protected]>
>> ---
>> mm/memblock.c | 3 +++
>> 1 file changed, 3 insertions(+)
>>
>> diff --git a/mm/memblock.c b/mm/memblock.c
>> index 049df41..f65af9f 100644
>> --- a/mm/memblock.c
>> +++ b/mm/memblock.c
>> @@ -1419,6 +1419,9 @@ phys_addr_t __init memblock_phys_alloc_range(phys_addr_t size,
>> phys_addr_t start,
>> phys_addr_t end)
>> {
>> + memblock_dbg("%s: %llu bytes align=0x%llx from=%pa max_addr=%pa %pS\n",
>> + __func__, (u64)size, (u64)align, &start, &end,
>> + (void *)_RET_IP_);
>> return memblock_alloc_range_nid(size, align, start, end, NUMA_NO_NODE,
>> false);
>> }
>> --
>> QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a
>> member of the Code Aurora Forum, hosted by The Linux Foundation
>>

2020-11-11 12:34:08

by Mike Rapoport

[permalink] [raw]
Subject: Re: [PATCH] mm: memblock: add more debug logs

On Wed, Nov 11, 2020 at 01:30:40PM +0530, Faiyaz Mohammed wrote:
>
> On 11/10/2020 11:46 PM, Mike Rapoport wrote:
> > Hi,
> >
> > On Tue, Nov 10, 2020 at 05:49:58PM +0530, Faiyaz Mohammed wrote:
> > > Exact caller of memblock_phys_alloc_range is not available with
> > > "memblock=debug". Below information is not enough for memory accounting.
> > > for example:
> > > [ 0.000000] memblock_reserve: [0x000000023fc6b000-0x000000023fc6bfff] memblock_alloc_range_nid+0xc0/0x188
> > >
> > > To enhance the memblock_dbg information or to get the exact owner of the
> > > memblock_reserve, add debug logs in memblock_phys_alloc_range function.
> > Why would you want to use memblock=debug for memory accounting or for
> > tracking of the owners of the reserved memory?

> We do memblock reserved accounting to track owners to know size of memory
> allocated by different drivers/owners through memblock_reserve, which help
> in comparing different kernel version and in optimizations.

I'd suggest to update the commit messaget to somthing like:

It is usefull to know the exact caller of memblock_phys_alloc_range() to
track early memory reservations during developement.

Currently, when memblock debugging is enabled, the allocations done with
memblock_phys_alloc_range() are only reported at memblock_reserve():

[ 0.000000] memblock_reserve: [0x000000023fc6b000-0x000000023fc6bfff] memblock_alloc_range_nid+0xc0/0x188

Add memblock_dbg() to memblock_phys_alloc_range() to get details about
its usage.

For example:

[ 0.000000] memblock_phys_alloc_range: 4096 bytes align=0x1000 from=0x0000000000000000 max_addr=0x0000000000000000 early_pgtable_alloc+0x24/0x178
[ 0.000000] memblock_reserve: [0x000000023fc6b000-0x000000023fc6bfff] memblock_alloc_range_nid+0xc0/0x188

> > > After adding logs:
> > > [ 0.000000] memblock_phys_alloc_range: 4096 bytes align=0x1000 from=0x0000000000000000 max_addr=0x0000000000000000 early_pgtable_alloc+0x24/0x178
> > > [ 0.000000] memblock_reserve: [0x000000023fc6b000-0x000000023fc6bfff] memblock_alloc_range_nid+0xc0/0x188
> > >
> > > Signed-off-by: Faiyaz Mohammed <[email protected]>
> > > ---
> > > mm/memblock.c | 3 +++
> > > 1 file changed, 3 insertions(+)
> > >
> > > diff --git a/mm/memblock.c b/mm/memblock.c
> > > index 049df41..f65af9f 100644
> > > --- a/mm/memblock.c
> > > +++ b/mm/memblock.c
> > > @@ -1419,6 +1419,9 @@ phys_addr_t __init memblock_phys_alloc_range(phys_addr_t size,
> > > phys_addr_t start,
> > > phys_addr_t end)
> > > {
> > > + memblock_dbg("%s: %llu bytes align=0x%llx from=%pa max_addr=%pa %pS\n",
> > > + __func__, (u64)size, (u64)align, &start, &end,
> > > + (void *)_RET_IP_);
> > > return memblock_alloc_range_nid(size, align, start, end, NUMA_NO_NODE,
> > > false);
> > > }
> > > --
> > > QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a
> > > member of the Code Aurora Forum, hosted by The Linux Foundation
> > >

--
Sincerely yours,
Mike.