From: David Miller <davem@davemloft.net>
To: arnd@arndb.de
Cc: vishal@chelsio.com, rahul.lakkireddy@chelsio.com,
ganeshgr@chelsio.com, alexios.zavras@intel.com,
arjun@chelsio.com, surendra@chelsio.com, netdev@vger.kernel.org,
linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com
Subject: Re: [PATCH] [net-next] cxgb4: reduce kernel stack usage in cudbg_collect_mem_region()
Date: Fri, 12 Jul 2019 15:36:32 -0700 (PDT) [thread overview]
Message-ID: <20190712.153632.1007215196498198399.davem@davemloft.net> (raw)
In-Reply-To: <20190712090700.317887-1-arnd@arndb.de>
From: Arnd Bergmann <arnd@arndb.de>
Date: Fri, 12 Jul 2019 11:06:33 +0200
> The cudbg_collect_mem_region() and cudbg_read_fw_mem() both use several
> hundred kilobytes of kernel stack space. One gets inlined into the other,
> which causes the stack usage to be combined beyond the warning limit
> when building with clang:
>
> drivers/net/ethernet/chelsio/cxgb4/cudbg_lib.c:1057:12: error: stack frame size of 1244 bytes in function 'cudbg_collect_mem_region' [-Werror,-Wframe-larger-than=]
>
> Restructuring cudbg_collect_mem_region() lets clang do the same
> optimization that gcc does and reuse the stack slots as it can
> see that the large variables are never used together.
>
> A better fix might be to avoid using cudbg_meminfo on the stack
> altogether, but that requires a larger rewrite.
>
> Fixes: a1c69520f785 ("cxgb4: collect MC memory dump")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Applied.
next prev parent reply other threads:[~2019-07-12 22:36 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-07-12 9:06 [PATCH] [net-next] cxgb4: reduce kernel stack usage in cudbg_collect_mem_region() Arnd Bergmann
2019-07-12 22:36 ` David Miller [this message]
2019-07-13 0:14 ` Joe Perches
2019-07-13 15:35 ` Arnd Bergmann
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=20190712.153632.1007215196498198399.davem@davemloft.net \
--to=davem@davemloft.net \
--cc=alexios.zavras@intel.com \
--cc=arjun@chelsio.com \
--cc=arnd@arndb.de \
--cc=clang-built-linux@googlegroups.com \
--cc=ganeshgr@chelsio.com \
--cc=linux-kernel@vger.kernel.org \
--cc=netdev@vger.kernel.org \
--cc=rahul.lakkireddy@chelsio.com \
--cc=surendra@chelsio.com \
--cc=vishal@chelsio.com \
/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).