From: "Kirill A. Shutemov" <kirill@shutemov.name>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>,
"Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
Ingo Molnar <mingo@redhat.com>,
linux-kernel@vger.kernel.org, linux-mm@kvack.org,
linux-arch@vger.kernel.org
Subject: Re: [PATCH] mm: create a separate slab for page->ptl allocation
Date: Wed, 6 Nov 2013 15:21:55 +0200 [thread overview]
Message-ID: <20131106132155.GA22132@shutemov.name> (raw)
In-Reply-To: <20131106093131.GU28601@twins.programming.kicks-ass.net>
On Wed, Nov 06, 2013 at 10:31:31AM +0100, Peter Zijlstra wrote:
> On Wed, Nov 06, 2013 at 01:13:11AM +0200, Kirill A. Shutemov wrote:
> > I would like to get rid of __ptlock_alloc()/__ptlock_free() too, but I
> > don't see a way within C: we need to know sizeof(spinlock_t) on
> > preprocessor stage.
> >
> > We can have a hack on kbuild level: write small helper program to find out
> > sizeof(spinlock_t) before start building and turn it into define.
> > But it's overkill from my POV. And cross-compilation will be a fun.
>
> Ah, I just remembered, we have such a thing!
Great!
> @@ -1354,7 +1356,7 @@ static inline bool ptlock_init(struct page *page)
> * slab code uses page->slab_cache and page->first_page (for tail
> * pages), which share storage with page->ptl.
> */
> - VM_BUG_ON(page->ptl);
> + VM_BUG_ON(*(unsigned long *)&page->ptl);
Huh? Why not direct cast to unsigned long?
VM_BUG_ON((unsigned long)page->ptl);
Otherwise:
Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
--
Kirill A. Shutemov
--
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>
WARNING: multiple messages have this Message-ID (diff)
From: "Kirill A. Shutemov" <kirill@shutemov.name>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>,
"Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
Ingo Molnar <mingo@redhat.com>,
linux-kernel@vger.kernel.org, linux-mm@kvack.org,
linux-arch@vger.kernel.org
Subject: Re: [PATCH] mm: create a separate slab for page->ptl allocation
Date: Wed, 6 Nov 2013 15:21:55 +0200 [thread overview]
Message-ID: <20131106132155.GA22132@shutemov.name> (raw)
Message-ID: <20131106132155.QS7Lmq631oiTLNmY_vG9sS42jvjfR_hq5BjKuvyFzDU@z> (raw)
In-Reply-To: <20131106093131.GU28601@twins.programming.kicks-ass.net>
On Wed, Nov 06, 2013 at 10:31:31AM +0100, Peter Zijlstra wrote:
> On Wed, Nov 06, 2013 at 01:13:11AM +0200, Kirill A. Shutemov wrote:
> > I would like to get rid of __ptlock_alloc()/__ptlock_free() too, but I
> > don't see a way within C: we need to know sizeof(spinlock_t) on
> > preprocessor stage.
> >
> > We can have a hack on kbuild level: write small helper program to find out
> > sizeof(spinlock_t) before start building and turn it into define.
> > But it's overkill from my POV. And cross-compilation will be a fun.
>
> Ah, I just remembered, we have such a thing!
Great!
> @@ -1354,7 +1356,7 @@ static inline bool ptlock_init(struct page *page)
> * slab code uses page->slab_cache and page->first_page (for tail
> * pages), which share storage with page->ptl.
> */
> - VM_BUG_ON(page->ptl);
> + VM_BUG_ON(*(unsigned long *)&page->ptl);
Huh? Why not direct cast to unsigned long?
VM_BUG_ON((unsigned long)page->ptl);
Otherwise:
Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
--
Kirill A. Shutemov
next prev parent reply other threads:[~2013-11-06 13:21 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-10-22 11:53 [PATCH] mm: create a separate slab for page->ptl allocation Kirill A. Shutemov
2013-10-22 11:53 ` Kirill A. Shutemov
2013-10-22 12:55 ` Fengguang Wu
2013-10-22 12:55 ` Fengguang Wu
2013-11-04 10:42 ` Kirill A. Shutemov
2013-11-04 10:42 ` Kirill A. Shutemov
2013-11-05 23:01 ` Andrew Morton
2013-11-05 23:01 ` Andrew Morton
2013-11-05 22:42 ` Kirill A. Shutemov
2013-11-05 22:42 ` Kirill A. Shutemov
2013-11-05 23:56 ` Andrew Morton
2013-11-05 23:56 ` Andrew Morton
2013-11-05 23:13 ` Kirill A. Shutemov
2013-11-05 23:13 ` Kirill A. Shutemov
2013-11-06 0:43 ` Andrew Morton
2013-11-06 0:43 ` Andrew Morton
2013-11-06 9:31 ` Peter Zijlstra
2013-11-06 9:31 ` Peter Zijlstra
2013-11-06 11:18 ` Peter Zijlstra
2013-11-06 11:18 ` Peter Zijlstra
2013-11-06 13:31 ` lockref: Use bloated_spinlocks to avoid explicit config dependencies Kirill A. Shutemov
2013-11-06 13:31 ` Kirill A. Shutemov
2013-11-06 14:32 ` Peter Zijlstra
2013-11-06 14:32 ` Peter Zijlstra
2013-11-06 13:21 ` Kirill A. Shutemov [this message]
2013-11-06 13:21 ` [PATCH] mm: create a separate slab for page->ptl allocation Kirill A. Shutemov
2013-11-06 14:30 ` Peter Zijlstra
2013-11-06 14:30 ` Peter Zijlstra
2013-11-06 10:34 ` Will Deacon
2013-11-06 10:34 ` Will Deacon
2013-11-06 10:49 ` Geert Uytterhoeven
2013-11-06 10:49 ` Geert Uytterhoeven
2013-11-06 11:02 ` Peter Zijlstra
2013-11-06 11:02 ` Peter Zijlstra
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=20131106132155.GA22132@shutemov.name \
--to=kirill@shutemov.name \
--cc=akpm@linux-foundation.org \
--cc=kirill.shutemov@linux.intel.com \
--cc=linux-arch@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mingo@redhat.com \
--cc=peterz@infradead.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.