From: "Michał Nazarewicz" <m.nazarewicz@samsung.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>,
linux-kernel@vger.kernel.org, m.szyprowski@samsung.com,
kyungmin.park@samsung.com, linux-mm@kvack.org
Subject: Re: [PATCH] Physical Memory Management [0/1]
Date: Thu, 14 May 2009 13:48:39 +0200 [thread overview]
Message-ID: <op.utw4fdhz7p4s8u@amdc030> (raw)
In-Reply-To: <1242300002.6642.1091.camel@laptop>
> On Thu, 2009-05-14 at 11:00 +0200, Michał Nazarewicz wrote:
>> PMM solves this problem since the buffers are allocated when they
>> are needed.
On Thu, 14 May 2009 13:20:02 +0200, Peter Zijlstra wrote:
> Ha - only when you actually manage to allocate things. Physically
> contiguous allocations are exceedingly hard once the machine has been
> running for a while.
PMM reserves memory during boot time using alloc_bootmem_low_pages().
After this is done, it can allocate buffers from reserved pool.
The idea here is that there are n hardware accelerators, each
can operate on 1MiB blocks (to simplify assume that's the case).
However, we know that at most m < n devices will be used at the same
time so instead of reserving n MiBs of memory we reserve only m MiBs.
--
Best regards, _ _
.o. | Liege of Serenly Enlightened Majesty of o' \,=./ `o
..o | Computer Science, Michał "mina86" Nazarewicz (o o)
ooo +-<m.nazarewicz@samsung.com>-<mina86@jabber.org>-ooO--(_)--Ooo--
WARNING: multiple messages have this Message-ID (diff)
From: "Michał Nazarewicz" <m.nazarewicz@samsung.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>,
linux-kernel@vger.kernel.org, m.szyprowski@samsung.com,
kyungmin.park@samsung.com, linux-mm@kvack.org
Subject: Re: [PATCH] Physical Memory Management [0/1]
Date: Thu, 14 May 2009 13:48:39 +0200 [thread overview]
Message-ID: <op.utw4fdhz7p4s8u@amdc030> (raw)
In-Reply-To: <1242300002.6642.1091.camel@laptop>
> On Thu, 2009-05-14 at 11:00 +0200, MichaA? Nazarewicz wrote:
>> PMM solves this problem since the buffers are allocated when they
>> are needed.
On Thu, 14 May 2009 13:20:02 +0200, Peter Zijlstra wrote:
> Ha - only when you actually manage to allocate things. Physically
> contiguous allocations are exceedingly hard once the machine has been
> running for a while.
PMM reserves memory during boot time using alloc_bootmem_low_pages().
After this is done, it can allocate buffers from reserved pool.
The idea here is that there are n hardware accelerators, each
can operate on 1MiB blocks (to simplify assume that's the case).
However, we know that at most m < n devices will be used at the same
time so instead of reserving n MiBs of memory we reserve only m MiBs.
--
Best regards, _ _
.o. | Liege of Serenly Enlightened Majesty of o' \,=./ `o
..o | Computer Science, MichaA? "mina86" Nazarewicz (o o)
ooo +-<m.nazarewicz@samsung.com>-<mina86@jabber.org>-ooO--(_)--Ooo--
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next prev parent reply other threads:[~2009-05-14 11:49 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-05-13 9:26 [PATCH] Physical Memory Management [0/1] Michał Nazarewicz
2009-05-13 9:27 ` [PATCH] Physical Memory Management [1/1] Michał Nazarewicz
2009-05-13 22:11 ` [PATCH] Physical Memory Management [0/1] Andrew Morton
2009-05-13 22:11 ` Andrew Morton
2009-05-14 9:00 ` Michał Nazarewicz
2009-05-14 9:00 ` Michał Nazarewicz
2009-05-14 11:20 ` Peter Zijlstra
2009-05-14 11:20 ` Peter Zijlstra
2009-05-14 11:48 ` Michał Nazarewicz [this message]
2009-05-14 11:48 ` Michał Nazarewicz
2009-05-14 12:05 ` Peter Zijlstra
2009-05-14 12:05 ` Peter Zijlstra
2009-05-14 13:04 ` Michał Nazarewicz
2009-05-14 13:04 ` Michał Nazarewicz
2009-05-14 17:07 ` Andrew Morton
2009-05-14 17:07 ` Andrew Morton
2009-05-14 17:10 ` Peter Zijlstra
2009-05-14 17:10 ` Peter Zijlstra
2009-05-15 10:06 ` Michał Nazarewicz
2009-05-15 10:06 ` Michał Nazarewicz
2009-05-15 10:18 ` Andi Kleen
2009-05-15 10:18 ` Andi Kleen
2009-05-15 10:47 ` Michał Nazarewicz
2009-05-15 10:47 ` Michał Nazarewicz
2009-05-15 11:03 ` Peter Zijlstra
2009-05-15 11:03 ` Peter Zijlstra
2009-05-15 11:11 ` Michał Nazarewicz
2009-05-15 11:11 ` Michał Nazarewicz
2009-05-15 11:26 ` Andi Kleen
2009-05-15 11:26 ` Andi Kleen
2009-05-15 12:05 ` Michał Nazarewicz
2009-05-15 12:05 ` Michał Nazarewicz
2009-05-14 19:33 ` Andi Kleen
2009-05-14 19:33 ` Andi Kleen
-- strict thread matches above, loose matches on Subject: below --
2009-05-13 9:23 Michał Nazarewicz
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