Modify the name of the existing zswap_pool_get() to zswap_pool_tryget()
to be representative of the call it makes to percpu_ref_tryget().
A subsequent patch will introduce a new zswap_pool_get() that calls
percpu_ref_get().
The intent behind this change is for higher level zswap API such as
zswap_store() to call zswap_pool_tryget() to check upfront if the pool's
refcount is "0" (which means it could be getting destroyed) and to handle
this as an error condition. zswap_store() would proceed only if
zswap_pool_tryget() returns success, and any additional pool refcounts that
need to be obtained for compressing sub-pages in a large folio could simply
call zswap_pool_get().
Signed-off-by: Kanchana P Sridhar <kanchana.p.sridhar@intel.com>
---
mm/zswap.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/mm/zswap.c b/mm/zswap.c
index fd7a8c14457a..0f281e50a034 100644
--- a/mm/zswap.c
+++ b/mm/zswap.c
@@ -403,7 +403,7 @@ static void __zswap_pool_empty(struct percpu_ref *ref)
spin_unlock_bh(&zswap_pools_lock);
}
-static int __must_check zswap_pool_get(struct zswap_pool *pool)
+static int __must_check zswap_pool_tryget(struct zswap_pool *pool)
{
if (!pool)
return 0;
@@ -441,7 +441,7 @@ static struct zswap_pool *zswap_pool_current_get(void)
rcu_read_lock();
pool = __zswap_pool_current();
- if (!zswap_pool_get(pool))
+ if (!zswap_pool_tryget(pool))
pool = NULL;
rcu_read_unlock();
@@ -462,7 +462,7 @@ static struct zswap_pool *zswap_pool_find_get(char *type, char *compressor)
if (strcmp(zpool_get_type(pool->zpool), type))
continue;
/* if we can't get it, it's about to be destroyed */
- if (!zswap_pool_get(pool))
+ if (!zswap_pool_tryget(pool))
continue;
return pool;
}
--
2.27.0
On Fri, Sep 27, 2024 at 7:16 PM Kanchana P Sridhar <kanchana.p.sridhar@intel.com> wrote: > > Modify the name of the existing zswap_pool_get() to zswap_pool_tryget() > to be representative of the call it makes to percpu_ref_tryget(). > A subsequent patch will introduce a new zswap_pool_get() that calls > percpu_ref_get(). > > The intent behind this change is for higher level zswap API such as > zswap_store() to call zswap_pool_tryget() to check upfront if the pool's > refcount is "0" (which means it could be getting destroyed) and to handle > this as an error condition. zswap_store() would proceed only if > zswap_pool_tryget() returns success, and any additional pool refcounts that > need to be obtained for compressing sub-pages in a large folio could simply > call zswap_pool_get(). > > Signed-off-by: Kanchana P Sridhar <kanchana.p.sridhar@intel.com> Reviewed-by: Nhat Pham <nphamcs@gmail.com>
> -----Original Message----- > From: Nhat Pham <nphamcs@gmail.com> > Sent: Saturday, September 28, 2024 4:27 PM > To: Sridhar, Kanchana P <kanchana.p.sridhar@intel.com> > Cc: linux-kernel@vger.kernel.org; linux-mm@kvack.org; > hannes@cmpxchg.org; yosryahmed@google.com; > chengming.zhou@linux.dev; usamaarif642@gmail.com; > shakeel.butt@linux.dev; ryan.roberts@arm.com; Huang, Ying > <ying.huang@intel.com>; 21cnbao@gmail.com; akpm@linux-foundation.org; > Zou, Nanhai <nanhai.zou@intel.com>; Feghali, Wajdi K > <wajdi.k.feghali@intel.com>; Gopal, Vinodh <vinodh.gopal@intel.com> > Subject: Re: [PATCH v8 3/8] mm: zswap: Rename zswap_pool_get() to > zswap_pool_tryget(). > > On Fri, Sep 27, 2024 at 7:16 PM Kanchana P Sridhar > <kanchana.p.sridhar@intel.com> wrote: > > > > Modify the name of the existing zswap_pool_get() to zswap_pool_tryget() > > to be representative of the call it makes to percpu_ref_tryget(). > > A subsequent patch will introduce a new zswap_pool_get() that calls > > percpu_ref_get(). > > > > The intent behind this change is for higher level zswap API such as > > zswap_store() to call zswap_pool_tryget() to check upfront if the pool's > > refcount is "0" (which means it could be getting destroyed) and to handle > > this as an error condition. zswap_store() would proceed only if > > zswap_pool_tryget() returns success, and any additional pool refcounts that > > need to be obtained for compressing sub-pages in a large folio could simply > > call zswap_pool_get(). > > > > Signed-off-by: Kanchana P Sridhar <kanchana.p.sridhar@intel.com> > > Reviewed-by: Nhat Pham <nphamcs@gmail.com> Thanks Nhat! Thanks, Kanchana
On Fri, Sep 27, 2024 at 07:16:15PM -0700, Kanchana P Sridhar wrote: > Modify the name of the existing zswap_pool_get() to zswap_pool_tryget() > to be representative of the call it makes to percpu_ref_tryget(). > A subsequent patch will introduce a new zswap_pool_get() that calls > percpu_ref_get(). > > The intent behind this change is for higher level zswap API such as > zswap_store() to call zswap_pool_tryget() to check upfront if the pool's > refcount is "0" (which means it could be getting destroyed) and to handle > this as an error condition. zswap_store() would proceed only if > zswap_pool_tryget() returns success, and any additional pool refcounts that > need to be obtained for compressing sub-pages in a large folio could simply > call zswap_pool_get(). > > Signed-off-by: Kanchana P Sridhar <kanchana.p.sridhar@intel.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org>
On 2024/9/28 10:16, Kanchana P Sridhar wrote:
> Modify the name of the existing zswap_pool_get() to zswap_pool_tryget()
> to be representative of the call it makes to percpu_ref_tryget().
> A subsequent patch will introduce a new zswap_pool_get() that calls
> percpu_ref_get().
>
> The intent behind this change is for higher level zswap API such as
> zswap_store() to call zswap_pool_tryget() to check upfront if the pool's
> refcount is "0" (which means it could be getting destroyed) and to handle
> this as an error condition. zswap_store() would proceed only if
> zswap_pool_tryget() returns success, and any additional pool refcounts that
> need to be obtained for compressing sub-pages in a large folio could simply
> call zswap_pool_get().
>
> Signed-off-by: Kanchana P Sridhar <kanchana.p.sridhar@intel.com>
Reviewed-by: Chengming Zhou <chengming.zhou@linux.dev>
> ---
> mm/zswap.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/mm/zswap.c b/mm/zswap.c
> index fd7a8c14457a..0f281e50a034 100644
> --- a/mm/zswap.c
> +++ b/mm/zswap.c
> @@ -403,7 +403,7 @@ static void __zswap_pool_empty(struct percpu_ref *ref)
> spin_unlock_bh(&zswap_pools_lock);
> }
>
> -static int __must_check zswap_pool_get(struct zswap_pool *pool)
> +static int __must_check zswap_pool_tryget(struct zswap_pool *pool)
> {
> if (!pool)
> return 0;
> @@ -441,7 +441,7 @@ static struct zswap_pool *zswap_pool_current_get(void)
> rcu_read_lock();
>
> pool = __zswap_pool_current();
> - if (!zswap_pool_get(pool))
> + if (!zswap_pool_tryget(pool))
> pool = NULL;
>
> rcu_read_unlock();
> @@ -462,7 +462,7 @@ static struct zswap_pool *zswap_pool_find_get(char *type, char *compressor)
> if (strcmp(zpool_get_type(pool->zpool), type))
> continue;
> /* if we can't get it, it's about to be destroyed */
> - if (!zswap_pool_get(pool))
> + if (!zswap_pool_tryget(pool))
> continue;
> return pool;
> }
> -----Original Message-----
> From: Chengming Zhou <chengming.zhou@linux.dev>
> Sent: Friday, September 27, 2024 10:44 PM
> To: Sridhar, Kanchana P <kanchana.p.sridhar@intel.com>; linux-
> kernel@vger.kernel.org; linux-mm@kvack.org; hannes@cmpxchg.org;
> yosryahmed@google.com; nphamcs@gmail.com; usamaarif642@gmail.com;
> shakeel.butt@linux.dev; ryan.roberts@arm.com; Huang, Ying
> <ying.huang@intel.com>; 21cnbao@gmail.com; akpm@linux-foundation.org
> Cc: Zou, Nanhai <nanhai.zou@intel.com>; Feghali, Wajdi K
> <wajdi.k.feghali@intel.com>; Gopal, Vinodh <vinodh.gopal@intel.com>
> Subject: Re: [PATCH v8 3/8] mm: zswap: Rename zswap_pool_get() to
> zswap_pool_tryget().
>
> On 2024/9/28 10:16, Kanchana P Sridhar wrote:
> > Modify the name of the existing zswap_pool_get() to zswap_pool_tryget()
> > to be representative of the call it makes to percpu_ref_tryget().
> > A subsequent patch will introduce a new zswap_pool_get() that calls
> > percpu_ref_get().
> >
> > The intent behind this change is for higher level zswap API such as
> > zswap_store() to call zswap_pool_tryget() to check upfront if the pool's
> > refcount is "0" (which means it could be getting destroyed) and to handle
> > this as an error condition. zswap_store() would proceed only if
> > zswap_pool_tryget() returns success, and any additional pool refcounts that
> > need to be obtained for compressing sub-pages in a large folio could simply
> > call zswap_pool_get().
> >
> > Signed-off-by: Kanchana P Sridhar <kanchana.p.sridhar@intel.com>
>
> Reviewed-by: Chengming Zhou <chengming.zhou@linux.dev>
Thanks Chengming!
Thanks,
Kanchana
>
> > ---
> > mm/zswap.c | 6 +++---
> > 1 file changed, 3 insertions(+), 3 deletions(-)
> >
> > diff --git a/mm/zswap.c b/mm/zswap.c
> > index fd7a8c14457a..0f281e50a034 100644
> > --- a/mm/zswap.c
> > +++ b/mm/zswap.c
> > @@ -403,7 +403,7 @@ static void __zswap_pool_empty(struct percpu_ref
> *ref)
> > spin_unlock_bh(&zswap_pools_lock);
> > }
> >
> > -static int __must_check zswap_pool_get(struct zswap_pool *pool)
> > +static int __must_check zswap_pool_tryget(struct zswap_pool *pool)
> > {
> > if (!pool)
> > return 0;
> > @@ -441,7 +441,7 @@ static struct zswap_pool
> *zswap_pool_current_get(void)
> > rcu_read_lock();
> >
> > pool = __zswap_pool_current();
> > - if (!zswap_pool_get(pool))
> > + if (!zswap_pool_tryget(pool))
> > pool = NULL;
> >
> > rcu_read_unlock();
> > @@ -462,7 +462,7 @@ static struct zswap_pool
> *zswap_pool_find_get(char *type, char *compressor)
> > if (strcmp(zpool_get_type(pool->zpool), type))
> > continue;
> > /* if we can't get it, it's about to be destroyed */
> > - if (!zswap_pool_get(pool))
> > + if (!zswap_pool_tryget(pool))
> > continue;
> > return pool;
> > }
On Fri, Sep 27, 2024 at 7:16 PM Kanchana P Sridhar
<kanchana.p.sridhar@intel.com> wrote:
>
> Modify the name of the existing zswap_pool_get() to zswap_pool_tryget()
> to be representative of the call it makes to percpu_ref_tryget().
> A subsequent patch will introduce a new zswap_pool_get() that calls
> percpu_ref_get().
>
> The intent behind this change is for higher level zswap API such as
> zswap_store() to call zswap_pool_tryget() to check upfront if the pool's
> refcount is "0" (which means it could be getting destroyed) and to handle
> this as an error condition. zswap_store() would proceed only if
> zswap_pool_tryget() returns success, and any additional pool refcounts that
> need to be obtained for compressing sub-pages in a large folio could simply
> call zswap_pool_get().
>
> Signed-off-by: Kanchana P Sridhar <kanchana.p.sridhar@intel.com>
Acked-by: Yosry Ahmed <yosryahmed@google.com>
> ---
> mm/zswap.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/mm/zswap.c b/mm/zswap.c
> index fd7a8c14457a..0f281e50a034 100644
> --- a/mm/zswap.c
> +++ b/mm/zswap.c
> @@ -403,7 +403,7 @@ static void __zswap_pool_empty(struct percpu_ref *ref)
> spin_unlock_bh(&zswap_pools_lock);
> }
>
> -static int __must_check zswap_pool_get(struct zswap_pool *pool)
> +static int __must_check zswap_pool_tryget(struct zswap_pool *pool)
> {
> if (!pool)
> return 0;
> @@ -441,7 +441,7 @@ static struct zswap_pool *zswap_pool_current_get(void)
> rcu_read_lock();
>
> pool = __zswap_pool_current();
> - if (!zswap_pool_get(pool))
> + if (!zswap_pool_tryget(pool))
> pool = NULL;
>
> rcu_read_unlock();
> @@ -462,7 +462,7 @@ static struct zswap_pool *zswap_pool_find_get(char *type, char *compressor)
> if (strcmp(zpool_get_type(pool->zpool), type))
> continue;
> /* if we can't get it, it's about to be destroyed */
> - if (!zswap_pool_get(pool))
> + if (!zswap_pool_tryget(pool))
> continue;
> return pool;
> }
> --
> 2.27.0
>
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