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 <joe...@google.com> 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 <joe...@google.com>
> ---
> 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
>
