Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934966AbcJHFoe (ORCPT ); Sat, 8 Oct 2016 01:44:34 -0400 Received: from mail-wm0-f45.google.com ([74.125.82.45]:36697 "EHLO mail-wm0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932167AbcJHFo0 (ORCPT ); Sat, 8 Oct 2016 01:44:26 -0400 MIME-Version: 1.0 In-Reply-To: <1475904515-24970-2-git-send-email-joelaf@google.com> References: <1475904515-24970-1-git-send-email-joelaf@google.com> <1475904515-24970-2-git-send-email-joelaf@google.com> From: Joel Fernandes Date: Fri, 7 Oct 2016 22:44:24 -0700 Message-ID: Subject: Re: [PATCH 1/7] pstore: Make spinlock per zone instead of global To: linux-kernel@vger.kernel.org Cc: Steven Rostedt , Joel Fernandes , Anton Vorontsov , Colin Cross , Kees Cook , Tony Luck Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3291 Lines: 93 Apologies that not everyone got CC'd on the cover letter, like the rest of the patch series: https://lkml.org/lkml/2016/10/8/12 Also, this patch series is an RFC, I screwed up the subject line. Thanks, Joel On Fri, Oct 7, 2016 at 10:28 PM, Joel Fernandes wrote: > > Currently pstore has a global spinlock for all zones. Since the zones are > independent and modify different areas of memory, there's no need to have > a global lock, make the lock per-zone to protect the respective zone. > > Signed-off-by: Joel Fernandes > --- > fs/pstore/ram_core.c | 11 +++++------ > include/linux/pstore_ram.h | 1 + > 2 files changed, 6 insertions(+), 6 deletions(-) > > diff --git a/fs/pstore/ram_core.c b/fs/pstore/ram_core.c > index 3975dee..cb92055 100644 > --- a/fs/pstore/ram_core.c > +++ b/fs/pstore/ram_core.c > @@ -48,8 +48,6 @@ static inline size_t buffer_start(struct persistent_ram_zone *prz) > return atomic_read(&prz->buffer->start); > } > > -static DEFINE_RAW_SPINLOCK(buffer_lock); > - > /* increase and wrap the start pointer, returning the old value */ > static size_t buffer_start_add(struct persistent_ram_zone *prz, size_t a) > { > @@ -57,7 +55,7 @@ static size_t buffer_start_add(struct persistent_ram_zone *prz, size_t a) > int new; > unsigned long flags; > > - raw_spin_lock_irqsave(&buffer_lock, flags); > + raw_spin_lock_irqsave(&prz->buffer_lock, flags); > > old = atomic_read(&prz->buffer->start); > new = old + a; > @@ -65,7 +63,7 @@ static size_t buffer_start_add(struct persistent_ram_zone *prz, size_t a) > new -= prz->buffer_size; > atomic_set(&prz->buffer->start, new); > > - raw_spin_unlock_irqrestore(&buffer_lock, flags); > + raw_spin_unlock_irqrestore(&prz->buffer_lock, flags); > > return old; > } > @@ -77,7 +75,7 @@ static void buffer_size_add(struct persistent_ram_zone *prz, size_t a) > size_t new; > unsigned long flags; > > - raw_spin_lock_irqsave(&buffer_lock, flags); > + raw_spin_lock_irqsave(&prz->buffer_lock, flags); > > old = atomic_read(&prz->buffer->size); > if (old == prz->buffer_size) > @@ -89,7 +87,7 @@ static void buffer_size_add(struct persistent_ram_zone *prz, size_t a) > atomic_set(&prz->buffer->size, new); > > exit: > - raw_spin_unlock_irqrestore(&buffer_lock, flags); > + raw_spin_unlock_irqrestore(&prz->buffer_lock, flags); > } > > static void notrace persistent_ram_encode_rs8(struct persistent_ram_zone *prz, > @@ -493,6 +491,7 @@ static int persistent_ram_post_init(struct persistent_ram_zone *prz, u32 sig, > > prz->buffer->sig = sig; > persistent_ram_zap(prz); > + prz->buffer_lock = __RAW_SPIN_LOCK_UNLOCKED(buffer_lock); > > return 0; > } > diff --git a/include/linux/pstore_ram.h b/include/linux/pstore_ram.h > index c668c86..244d242 100644 > --- a/include/linux/pstore_ram.h > +++ b/include/linux/pstore_ram.h > @@ -40,6 +40,7 @@ struct persistent_ram_zone { > void *vaddr; > struct persistent_ram_buffer *buffer; > size_t buffer_size; > + raw_spinlock_t buffer_lock; > > /* ECC correction */ > char *par_buffer; > -- > 2.7.4 >