From: Brice Goglin <Brice.Goglin@inria.fr>
To: Keith Busch <keith.busch@intel.com>,
linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org,
linux-mm@kvack.org, linux-api@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Rafael Wysocki <rafael@kernel.org>,
Dave Hansen <dave.hansen@intel.com>,
Dan Williams <dan.j.williams@intel.com>
Subject: Re: [PATCHv6 06/10] node: Add memory-side caching attributes
Date: Fri, 22 Feb 2019 11:12:38 +0100 [thread overview]
Message-ID: <29336223-b86e-3aca-ee5a-276d1c404b96@inria.fr> (raw)
In-Reply-To: <20190214171017.9362-7-keith.busch@intel.com>
Le 14/02/2019 à 18:10, Keith Busch a écrit :
> System memory may have caches to help improve access speed to frequently
> requested address ranges. While the system provided cache is transparent
> to the software accessing these memory ranges, applications can optimize
> their own access based on cache attributes.
>
> Provide a new API for the kernel to register these memory-side caches
> under the memory node that provides it.
>
> The new sysfs representation is modeled from the existing cpu cacheinfo
> attributes, as seen from /sys/devices/system/cpu/<cpu>/cache/. Unlike CPU
> cacheinfo though, the node cache level is reported from the view of the
> memory. A higher level number is nearer to the CPU, while lower levels
> are closer to the last level memory.
>
> The exported attributes are the cache size, the line size, associativity,
> and write back policy, and add the attributes for the system memory
> caches to sysfs stable documentation.
>
> Signed-off-by: Keith Busch <keith.busch@intel.com>
> ---
> Documentation/ABI/stable/sysfs-devices-node | 35 +++++++
> drivers/base/node.c | 151 ++++++++++++++++++++++++++++
> include/linux/node.h | 34 +++++++
> 3 files changed, 220 insertions(+)
>
> diff --git a/Documentation/ABI/stable/sysfs-devices-node b/Documentation/ABI/stable/sysfs-devices-node
> index cd64b62152ba..5c88cb9ca14e 100644
> --- a/Documentation/ABI/stable/sysfs-devices-node
> +++ b/Documentation/ABI/stable/sysfs-devices-node
> @@ -143,3 +143,38 @@ Contact: Keith Busch <keith.busch@intel.com>
> Description:
> This node's write latency in nanoseconds when access
> from nodes found in this class's linked initiators.
> +
> +What: /sys/devices/system/node/nodeX/memory_side_cache/indexY/
> +Date: December 2018
> +Contact: Keith Busch <keith.busch@intel.com>
> +Description:
> + The directory containing attributes for the memory-side cache
> + level 'Y'.
> +
> + The caches associativity: 0 for direct mapped, non-zero if
> +What: /sys/devices/system/node/nodeX/memory_side_cache/indexY/associativity
> +Date: December 2018
> +Contact: Keith Busch <keith.busch@intel.com>
> +Description:
> + The caches associativity: 0 for direct mapped, non-zero if
> + indexed.
> +
> +What: /sys/devices/system/node/nodeX/memory_side_cache/indexY/line_size
> +Date: December 2018
> +Contact: Keith Busch <keith.busch@intel.com>
> +Description:
> + The number of bytes accessed from the next cache level on a
> + cache miss.
> +
> +What: /sys/devices/system/node/nodeX/memory_side_cache/indexY/size
> +Date: December 2018
> +Contact: Keith Busch <keith.busch@intel.com>
> +Description:
> + The size of this memory side cache in bytes.
Hello Keith,
CPU-side cache size is reported in kilobytes:
$ cat
/sys/devices/system/cpu/cpu0/cache/index*/size
32K
32K
256K
4096K
Can you do the same of memory-side caches instead of reporting bytes?
Thanks
Brice
next prev parent reply other threads:[~2019-02-22 10:12 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-02-14 17:10 [PATCHv6 00/10] Heterogenous memory node attributes Keith Busch
2019-02-14 17:10 ` [PATCHv6 01/10] acpi: Create subtable parsing infrastructure Keith Busch
2019-02-14 17:10 ` [PATCHv6 02/10] acpi: Add HMAT to generic parsing tables Keith Busch
2019-02-14 17:10 ` [PATCHv6 03/10] acpi/hmat: Parse and report heterogeneous memory Keith Busch
2019-02-14 17:10 ` [PATCHv6 04/10] node: Link memory nodes to their compute nodes Keith Busch
2019-02-14 17:10 ` [PATCHv6 05/10] node: Add heterogenous memory access attributes Keith Busch
2019-02-14 17:10 ` [PATCHv6 06/10] node: Add memory-side caching attributes Keith Busch
2019-02-22 10:12 ` Brice Goglin [this message]
2019-02-22 18:09 ` Keith Busch
2019-02-22 18:20 ` Dan Williams
2019-02-22 10:22 ` Brice Goglin
2019-02-22 18:13 ` Keith Busch
2019-02-14 17:10 ` [PATCHv6 07/10] acpi/hmat: Register processor domain to its memory Keith Busch
2019-02-20 22:02 ` Rafael J. Wysocki
2019-02-20 22:11 ` Dave Hansen
2019-02-20 22:13 ` Dan Williams
2019-02-20 22:16 ` Rafael J. Wysocki
2019-02-20 22:20 ` Dan Williams
2019-02-20 22:21 ` Rafael J. Wysocki
2019-02-20 22:44 ` Keith Busch
2019-02-20 22:50 ` Rafael J. Wysocki
2019-02-22 18:48 ` Keith Busch
2019-02-22 19:21 ` Dan Williams
2019-02-24 20:07 ` Rafael J. Wysocki
2019-02-24 19:59 ` Rafael J. Wysocki
2019-02-25 16:51 ` Keith Busch
2019-02-25 22:30 ` Rafael J. Wysocki
2019-03-07 11:49 ` Brice Goglin
2019-03-07 15:19 ` Keith Busch
2019-02-14 17:10 ` [PATCHv6 08/10] acpi/hmat: Register performance attributes Keith Busch
2019-02-20 22:04 ` Rafael J. Wysocki
2019-02-14 17:10 ` [PATCHv6 09/10] acpi/hmat: Register memory side cache attributes Keith Busch
2019-02-20 22:05 ` Rafael J. Wysocki
2019-02-14 17:10 ` [PATCHv6 10/10] doc/mm: New documentation for memory performance Keith Busch
2019-02-18 14:25 ` [PATCHv6 00/10] Heterogenous memory node attributes Brice Goglin
2019-02-19 17:20 ` Keith Busch
2019-02-20 18:25 ` Keith Busch
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