From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Anton Blanchard <anton@samba.org>
Cc: linuxppc-dev@lists.ozlabs.org
Subject: Re: [PATCH] powerpc: Fix hypervisor TLB batching
Date: Mon, 12 Oct 2009 19:44:33 +1100 [thread overview]
Message-ID: <1255337073.2192.113.camel@pasglop> (raw)
In-Reply-To: <20091012074734.GB4808@kryten>
On Mon, 2009-10-12 at 18:47 +1100, Anton Blanchard wrote:
> Profiling of a page fault scalability microbenchmark shows flush_hash_range
> is not calling the batch hpte invalidate hcall (H_BULK_REMOVE).
>
> It turns out we have a duplicate firmware feature for hcall-bulk and the
> current setup code stops after finding the first match. This meant we never
> batch and always do individual invalidates.
>
> The patch below removes the duplicate and shifts FW_FEATURE_CMO to close
> the gap. With the patch applied the single threaded page fault rate improves
> from 217169 to 238755 per second on a POWER5 test box, a 10% improvement.
>
> Signed-off-by: Anton Blanchard <anton@samba.org>
> ---
Good catch !
Ben.
> Index: linux.trees.git/arch/powerpc/include/asm/firmware.h
> ===================================================================
> --- linux.trees.git.orig/arch/powerpc/include/asm/firmware.h 2009-10-12 18:11:56.000000000 +1100
> +++ linux.trees.git/arch/powerpc/include/asm/firmware.h 2009-10-12 18:21:20.000000000 +1100
> @@ -37,7 +37,7 @@
> #define FW_FEATURE_VIO ASM_CONST(0x0000000000004000)
> #define FW_FEATURE_RDMA ASM_CONST(0x0000000000008000)
> #define FW_FEATURE_LLAN ASM_CONST(0x0000000000010000)
> -#define FW_FEATURE_BULK ASM_CONST(0x0000000000020000)
> +#define FW_FEATURE_BULK_REMOVE ASM_CONST(0x0000000000020000)
> #define FW_FEATURE_XDABR ASM_CONST(0x0000000000040000)
> #define FW_FEATURE_MULTITCE ASM_CONST(0x0000000000080000)
> #define FW_FEATURE_SPLPAR ASM_CONST(0x0000000000100000)
> @@ -45,8 +45,7 @@
> #define FW_FEATURE_LPAR ASM_CONST(0x0000000000400000)
> #define FW_FEATURE_PS3_LV1 ASM_CONST(0x0000000000800000)
> #define FW_FEATURE_BEAT ASM_CONST(0x0000000001000000)
> -#define FW_FEATURE_BULK_REMOVE ASM_CONST(0x0000000002000000)
> -#define FW_FEATURE_CMO ASM_CONST(0x0000000004000000)
> +#define FW_FEATURE_CMO ASM_CONST(0x0000000002000000)
>
> #ifndef __ASSEMBLY__
>
> @@ -58,8 +57,9 @@ enum {
> FW_FEATURE_PERF | FW_FEATURE_DUMP | FW_FEATURE_INTERRUPT |
> FW_FEATURE_MIGRATE | FW_FEATURE_PERFMON | FW_FEATURE_CRQ |
> FW_FEATURE_VIO | FW_FEATURE_RDMA | FW_FEATURE_LLAN |
> - FW_FEATURE_BULK | FW_FEATURE_XDABR | FW_FEATURE_MULTITCE |
> - FW_FEATURE_SPLPAR | FW_FEATURE_LPAR | FW_FEATURE_CMO,
> + FW_FEATURE_BULK_REMOVE | FW_FEATURE_XDABR |
> + FW_FEATURE_MULTITCE | FW_FEATURE_SPLPAR | FW_FEATURE_LPAR |
> + FW_FEATURE_CMO,
> FW_FEATURE_PSERIES_ALWAYS = 0,
> FW_FEATURE_ISERIES_POSSIBLE = FW_FEATURE_ISERIES | FW_FEATURE_LPAR,
> FW_FEATURE_ISERIES_ALWAYS = FW_FEATURE_ISERIES | FW_FEATURE_LPAR,
> Index: linux.trees.git/arch/powerpc/platforms/pseries/firmware.c
> ===================================================================
> --- linux.trees.git.orig/arch/powerpc/platforms/pseries/firmware.c 2009-10-12 18:08:37.000000000 +1100
> +++ linux.trees.git/arch/powerpc/platforms/pseries/firmware.c 2009-10-12 18:12:54.000000000 +1100
> @@ -51,11 +51,10 @@ firmware_features_table[FIRMWARE_MAX_FEA
> {FW_FEATURE_VIO, "hcall-vio"},
> {FW_FEATURE_RDMA, "hcall-rdma"},
> {FW_FEATURE_LLAN, "hcall-lLAN"},
> - {FW_FEATURE_BULK, "hcall-bulk"},
> + {FW_FEATURE_BULK_REMOVE, "hcall-bulk"},
> {FW_FEATURE_XDABR, "hcall-xdabr"},
> {FW_FEATURE_MULTITCE, "hcall-multi-tce"},
> {FW_FEATURE_SPLPAR, "hcall-splpar"},
> - {FW_FEATURE_BULK_REMOVE, "hcall-bulk"},
> };
>
> /* Build up the firmware features bitmask using the contents of
prev parent reply other threads:[~2009-10-12 8:44 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-10-12 7:47 [PATCH] powerpc: Fix hypervisor TLB batching Anton Blanchard
2009-10-12 8:44 ` Benjamin Herrenschmidt [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1255337073.2192.113.camel@pasglop \
--to=benh@kernel.crashing.org \
--cc=anton@samba.org \
--cc=linuxppc-dev@lists.ozlabs.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.