From: Artem Bityutskiy <dedekind1@gmail.com>
To: Richard Weinberger <richard@nod.at>
Cc: linux-kernel@vger.kernel.org, Heinz.Egger@linutronix.de,
linux-mtd@lists.infradead.org, tim.bird@am.sony.com,
tglx@linutronix.de, Shmulik Ladkani <shmulik.ladkani@gmail.com>
Subject: Re: [PATCH] [RFC] UBI: Implement Fastmap support
Date: Thu, 24 May 2012 11:22:00 +0300 [thread overview]
Message-ID: <1337847720.15137.85.camel@sauron.fi.intel.com> (raw)
In-Reply-To: <4FBBC4EE.4040802@nod.at>
[-- Attachment #1: Type: text/plain, Size: 698 bytes --]
On Tue, 2012-05-22 at 18:55 +0200, Richard Weinberger wrote:
> >> + * has never seen any PEB used by the original fastmap.
> >> + */
> >> + if (!e) {
> >> + ubi_assert(ubi->old_fm);
> >> + e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_ATOMIC);
> >
> > Must it be GFP_ATOMIC?
>
> Yes. This function is called under a spinlock.
I did not look close, but this sounds bad.
You need to have a much better justification than "I allocate it under a
spinlock". You need to tell "... because there is no way or very
difficult to pre-allocate it while I do not have the spinlock held,
because ... (explanation)".
>
--
Best Regards,
Artem Bityutskiy
[-- Attachment #2: This is a digitally signed message part --]
[-- Type: application/pgp-signature, Size: 836 bytes --]
WARNING: multiple messages have this Message-ID (diff)
From: Artem Bityutskiy <dedekind1@gmail.com>
To: Richard Weinberger <richard@nod.at>
Cc: Shmulik Ladkani <shmulik.ladkani@gmail.com>,
linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org,
Heinz.Egger@linutronix.de, tim.bird@am.sony.com,
tglx@linutronix.de
Subject: Re: [PATCH] [RFC] UBI: Implement Fastmap support
Date: Thu, 24 May 2012 11:22:00 +0300 [thread overview]
Message-ID: <1337847720.15137.85.camel@sauron.fi.intel.com> (raw)
In-Reply-To: <4FBBC4EE.4040802@nod.at>
[-- Attachment #1: Type: text/plain, Size: 698 bytes --]
On Tue, 2012-05-22 at 18:55 +0200, Richard Weinberger wrote:
> >> + * has never seen any PEB used by the original fastmap.
> >> + */
> >> + if (!e) {
> >> + ubi_assert(ubi->old_fm);
> >> + e = kmem_cache_alloc(ubi_wl_entry_slab, GFP_ATOMIC);
> >
> > Must it be GFP_ATOMIC?
>
> Yes. This function is called under a spinlock.
I did not look close, but this sounds bad.
You need to have a much better justification than "I allocate it under a
spinlock". You need to tell "... because there is no way or very
difficult to pre-allocate it while I do not have the spinlock held,
because ... (explanation)".
>
--
Best Regards,
Artem Bityutskiy
[-- Attachment #2: This is a digitally signed message part --]
[-- Type: application/pgp-signature, Size: 836 bytes --]
next prev parent reply other threads:[~2012-05-24 8:18 UTC|newest]
Thread overview: 56+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-05-21 14:01 [RFC v6] UBI: Fastmap support (aka checkpointing) Richard Weinberger
2012-05-21 14:01 ` Richard Weinberger
2012-05-21 14:01 ` [PATCH] [RFC] UBI: Implement Fastmap support Richard Weinberger
2012-05-21 14:01 ` Richard Weinberger
2012-05-22 13:43 ` Artem Bityutskiy
2012-05-22 13:43 ` Artem Bityutskiy
2012-05-22 15:01 ` Shmulik Ladkani
2012-05-22 15:01 ` Shmulik Ladkani
2012-05-22 16:55 ` Richard Weinberger
2012-05-22 16:55 ` Richard Weinberger
2012-05-22 18:18 ` Shmulik Ladkani
2012-05-22 18:18 ` Shmulik Ladkani
2012-05-22 18:57 ` Richard Weinberger
2012-05-22 18:57 ` Richard Weinberger
2012-05-23 6:18 ` Shmulik Ladkani
2012-05-23 6:18 ` Shmulik Ladkani
2012-05-23 7:43 ` Richard Weinberger
2012-05-23 7:43 ` Richard Weinberger
2012-05-22 20:11 ` Richard Weinberger
2012-05-22 20:11 ` Richard Weinberger
2012-05-24 8:19 ` Artem Bityutskiy
2012-05-24 8:19 ` Artem Bityutskiy
2012-05-24 8:26 ` Richard Weinberger
2012-05-24 8:26 ` Richard Weinberger
2012-05-24 9:21 ` Artem Bityutskiy
2012-05-24 9:21 ` Artem Bityutskiy
2012-05-24 8:17 ` Artem Bityutskiy
2012-05-24 8:17 ` Artem Bityutskiy
2012-05-24 9:56 ` Shmulik Ladkani
2012-05-24 9:56 ` Shmulik Ladkani
2012-05-24 10:03 ` Richard Weinberger
2012-05-24 10:03 ` Richard Weinberger
2012-05-24 20:07 ` Shmulik Ladkani
2012-05-24 20:07 ` Shmulik Ladkani
2012-05-24 8:22 ` Artem Bityutskiy [this message]
2012-05-24 8:22 ` Artem Bityutskiy
2012-05-24 8:24 ` Richard Weinberger
2012-05-24 8:24 ` Richard Weinberger
-- strict thread matches above, loose matches on Subject: below --
2012-05-23 11:06 [RFC v7] UBI: Fastmap support (aka checkpointing) Richard Weinberger
2012-05-23 11:06 ` [PATCH] [RFC] UBI: Implement Fastmap support Richard Weinberger
2012-05-23 11:06 ` Richard Weinberger
2012-05-26 13:22 ` Artem Bityutskiy
2012-05-26 13:22 ` Artem Bityutskiy
2012-05-31 10:37 ` Adrian Hunter
2012-05-31 10:37 ` Adrian Hunter
2012-05-31 13:31 ` Richard Weinberger
2012-05-31 13:31 ` Richard Weinberger
2012-06-01 5:47 ` Adrian Hunter
2012-06-01 5:47 ` Adrian Hunter
2012-06-01 8:00 ` Richard Weinberger
2012-06-01 8:00 ` Richard Weinberger
2012-06-01 8:10 ` Artem Bityutskiy
2012-06-01 8:10 ` Artem Bityutskiy
2012-06-01 8:10 ` Richard Weinberger
2012-06-01 8:10 ` Richard Weinberger
2012-06-01 8:47 ` Adrian Hunter
2012-06-01 8:47 ` Adrian Hunter
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=1337847720.15137.85.camel@sauron.fi.intel.com \
--to=dedekind1@gmail.com \
--cc=Heinz.Egger@linutronix.de \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mtd@lists.infradead.org \
--cc=richard@nod.at \
--cc=shmulik.ladkani@gmail.com \
--cc=tglx@linutronix.de \
--cc=tim.bird@am.sony.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 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.