2021-01-05 00:50:38

by Zhaoyang Huang

Subject: [PATCH v2] fs: amend SLAB_RECLAIM_ACCOUNT on gfs2 related slab cache

From: Zhaoyang Huang <[email protected]>

As gfs2_quotad_cachep and gfs2_glock_cachep have registered
the shrinker, amending SLAB_RECLAIM_ACCOUNT when creating
them, which make the slab acount to be presiced.

Signed-off-by: Zhaoyang Huang <[email protected]>
---
v2: add gfs2_glock_cachep for same operation
---
---
fs/gfs2/main.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/gfs2/main.c b/fs/gfs2/main.c
index 136484e..23144a7 100644
--- a/fs/gfs2/main.c
+++ b/fs/gfs2/main.c
@@ -100,7 +100,7 @@ static int __init init_gfs2_fs(void)
error = -ENOMEM;
gfs2_glock_cachep = kmem_cache_create("gfs2_glock",
sizeof(struct gfs2_glock),
- 0, 0,
+ 0, SLAB_RECLAIM_ACCOUNT,
gfs2_init_glock_once);
if (!gfs2_glock_cachep)
goto fail_cachep1;
@@ -136,7 +136,7 @@ static int __init init_gfs2_fs(void)

gfs2_quotad_cachep = kmem_cache_create("gfs2_quotad",
sizeof(struct gfs2_quota_data),
- 0, 0, NULL);
+ 0, SLAB_RECLAIM_ACCOUNT, NULL);
if (!gfs2_quotad_cachep)
goto fail_cachep6;

--
1.9.1

2021-01-05 13:26:44

by Bob Peterson

Subject: Re: [PATCH v2] fs: amend SLAB_RECLAIM_ACCOUNT on gfs2 related slab cache

----- Original Message -----
> From: Zhaoyang Huang <[email protected]>
>
> As gfs2_quotad_cachep and gfs2_glock_cachep have registered
> the shrinker, amending SLAB_RECLAIM_ACCOUNT when creating
> them, which make the slab acount to be presiced.
>
> Signed-off-by: Zhaoyang Huang <[email protected]>
> ---
> v2: add gfs2_glock_cachep for same operation
> ---
Hi,

Thanks. Your patch is now pushed to the linux-gfs2/for-next branch.
I cleaned up the description a bit. For example, I changed "fs:" to
"gfs2:" to conform to other gfs2 patches.

Regards,

Bob Peterson

2021-01-05 23:04:58

by Andreas Grünbacher

Subject: Re: [PATCH v2] fs: amend SLAB_RECLAIM_ACCOUNT on gfs2 related slab cache

Bob,

Am Di., 5. Jan. 2021 um 14:28 Uhr schrieb Bob Peterson <[email protected]>:
> ----- Original Message -----
> > From: Zhaoyang Huang <[email protected]>
> >
> > As gfs2_quotad_cachep and gfs2_glock_cachep have registered
> > the shrinker, amending SLAB_RECLAIM_ACCOUNT when creating
> > them, which make the slab acount to be presiced.
> >
> > Signed-off-by: Zhaoyang Huang <[email protected]>
> > ---
> > v2: add gfs2_glock_cachep for same operation
> > ---
> Hi,
>
> Thanks. Your patch is now pushed to the linux-gfs2/for-next branch.
> I cleaned up the description a bit. For example, I changed "fs:" to
> "gfs2:" to conform to other gfs2 patches.

so the patch description now reads:

"As gfs2_quotad_cachep and gfs2_glock_cachep have registered
shrinkers, amending SLAB_RECLAIM_ACCOUNT when creating them,
which improves slab accounting."

I'm not sure what that description is based on; the definition of
SLAB_RECLAIM_ACCOUNT in include/linux/slab.h looks as follows, which
indicates that the purpose isn't really accounting but object
grouping:

/* The following flags affect the page allocator grouping pages by mobility */
/* Objects are reclaimable */
#define SLAB_RECLAIM_ACCOUNT ((slab_flags_t __force)0x00020000U)
#define SLAB_TEMPORARY SLAB_RECLAIM_ACCOUNT /* Objects are
short-lived */

Furthermore, would it make sense to use SLAB_RECLAIM_ACCOUNT or
SLAB_TEMPORARY for gfs2_bufdata and gfs2_trans as well?

Thanks,
Andreas