From: Anton Blanchard <anton@samba.org>
To: linuxppc-dev@ozlabs.org
Subject: [PATCH] Reduce hashtable size when using 64kB pages
Date: Sat, 14 Feb 2009 08:57:30 +1100 [thread overview]
Message-ID: <20090213215730.GF23273@kryten> (raw)
At the moment we size the hashtable based on 4kB pages / 2, even on a
64kB kernel. This results in a hashtable that is much larger than it
needs to be.
Grab the real page size and size the hashtable based on that. Note: this
only works on non hypervisor machines.
Signed-off-by: Anton Blanchard <anton@samba.org>
---
diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index 8d5b475..f5bc1b2 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -516,7 +516,7 @@ static int __init htab_dt_scan_pftsize(unsigned long node,
static unsigned long __init htab_get_table_size(void)
{
- unsigned long mem_size, rnd_mem_size, pteg_count;
+ unsigned long mem_size, rnd_mem_size, pteg_count, psize;
/* If hash size isn't already provided by the platform, we try to
* retrieve it from the device-tree. If it's not there neither, we
@@ -534,7 +534,8 @@ static unsigned long __init htab_get_table_size(void)
rnd_mem_size <<= 1;
/* # pages / 2 */
- pteg_count = max(rnd_mem_size >> (12 + 1), 1UL << 11);
+ psize = mmu_psize_defs[mmu_virtual_psize].shift;
+ pteg_count = max(rnd_mem_size >> (psize + 1), 1UL << 11);
return pteg_count << 7;
}
reply other threads:[~2009-02-13 21:57 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
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=20090213215730.GF23273@kryten \
--to=anton@samba.org \
--cc=linuxppc-dev@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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).