2016-04-20 19:13:43

by Paul Gortmaker

[permalink] [raw]
Subject: [PATCH] lib: make sg_pool explicitly non-modular

The recently added Kconfig controlling compilation of this code is:

lib/Kconfig:config SG_POOL
lib/Kconfig: def_bool n

...meaning that it currently is not being built as a module by anyone.

Lets remove the modular code that is essentially orphaned, so that
when reading the driver there is no doubt it is builtin-only.

Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit. However
one might want to consider moving it to subsys_initcall if it is to
be ready ahead of SCSI drivers wanting this and using device_initcall.

Cc: Christoph Hellwig <[email protected]>
Cc: Ming Lin <[email protected]>
Cc: Sagi Grimberg <[email protected]>
Cc: Martin K. Petersen <[email protected]>
Signed-off-by: Paul Gortmaker <[email protected]>
---
lib/sg_pool.c | 17 ++---------------
1 file changed, 2 insertions(+), 15 deletions(-)

diff --git a/lib/sg_pool.c b/lib/sg_pool.c
index 6dd30615a201..e2cf548b9610 100644
--- a/lib/sg_pool.c
+++ b/lib/sg_pool.c
@@ -1,4 +1,4 @@
-#include <linux/module.h>
+#include <linux/init.h>
#include <linux/scatterlist.h>
#include <linux/mempool.h>
#include <linux/slab.h>
@@ -156,17 +156,4 @@ cleanup_sdb:

return -ENOMEM;
}
-
-static __exit void sg_pool_exit(void)
-{
- int i;
-
- for (i = 0; i < SG_MEMPOOL_NR; i++) {
- struct sg_pool *sgp = sg_pools + i;
- mempool_destroy(sgp->pool);
- kmem_cache_destroy(sgp->slab);
- }
-}
-
-module_init(sg_pool_init);
-module_exit(sg_pool_exit);
+device_initcall(sg_pool_init);
--
2.8.0


2016-04-20 20:28:58

by Ming Lin

[permalink] [raw]
Subject: Re: [PATCH] lib: make sg_pool explicitly non-modular

On Wed, 2016-04-20 at 15:13 -0400, Paul Gortmaker wrote:
> The recently added Kconfig controlling compilation of this code is:
>
> lib/Kconfig:config SG_POOL
> lib/Kconfig: def_bool n
>
> ...meaning that it currently is not being built as a module by anyone.
>
> Lets remove the modular code that is essentially orphaned, so that
> when reading the driver there is no doubt it is builtin-only.
>
> Since module_init translates to device_initcall in the non-modular
> case, the init ordering remains unchanged with this commit. However
> one might want to consider moving it to subsys_initcall if it is to
> be ready ahead of SCSI drivers wanting this and using device_initcall.
>
> Cc: Christoph Hellwig <[email protected]>
> Cc: Ming Lin <[email protected]>
> Cc: Sagi Grimberg <[email protected]>
> Cc: Martin K. Petersen <[email protected]>
> Signed-off-by: Paul Gortmaker <[email protected]>
> ---
> lib/sg_pool.c | 17 ++---------------
> 1 file changed, 2 insertions(+), 15 deletions(-)
>
> diff --git a/lib/sg_pool.c b/lib/sg_pool.c
> index 6dd30615a201..e2cf548b9610 100644
> --- a/lib/sg_pool.c
> +++ b/lib/sg_pool.c
> @@ -1,4 +1,4 @@
> -#include <linux/module.h>
> +#include <linux/init.h>
> #include <linux/scatterlist.h>
> #include <linux/mempool.h>
> #include <linux/slab.h>
> @@ -156,17 +156,4 @@ cleanup_sdb:
>
> return -ENOMEM;
> }
> -
> -static __exit void sg_pool_exit(void)
> -{
> - int i;
> -
> - for (i = 0; i < SG_MEMPOOL_NR; i++) {
> - struct sg_pool *sgp = sg_pools + i;
> - mempool_destroy(sgp->pool);
> - kmem_cache_destroy(sgp->slab);
> - }
> -}
> -
> -module_init(sg_pool_init);
> -module_exit(sg_pool_exit);
> +device_initcall(sg_pool_init);

For SCSI it's OK because always CONFIG_SCSI=y

But we may have a kernel .config with !CONFIG_SCSI and other
non-block-device driver may use this sg_pool.

So the .config will have CONFIG_SG_POOL=m




2016-04-21 03:03:04

by Paul Gortmaker

[permalink] [raw]
Subject: Re: [PATCH] lib: make sg_pool explicitly non-modular

[Re: [PATCH] lib: make sg_pool explicitly non-modular] On 20/04/2016 (Wed 13:28) Ming Lin wrote:

> On Wed, 2016-04-20 at 15:13 -0400, Paul Gortmaker wrote:
> > The recently added Kconfig controlling compilation of this code is:
> >
> > lib/Kconfig:config SG_POOL
> > lib/Kconfig: def_bool n
> >
> > ...meaning that it currently is not being built as a module by anyone.
> >
> > Lets remove the modular code that is essentially orphaned, so that
> > when reading the driver there is no doubt it is builtin-only.
> >
> > Since module_init translates to device_initcall in the non-modular
> > case, the init ordering remains unchanged with this commit. However
> > one might want to consider moving it to subsys_initcall if it is to
> > be ready ahead of SCSI drivers wanting this and using device_initcall.
> >
> > Cc: Christoph Hellwig <[email protected]>
> > Cc: Ming Lin <[email protected]>
> > Cc: Sagi Grimberg <[email protected]>
> > Cc: Martin K. Petersen <[email protected]>
> > Signed-off-by: Paul Gortmaker <[email protected]>
> > ---
> > lib/sg_pool.c | 17 ++---------------
> > 1 file changed, 2 insertions(+), 15 deletions(-)
> >
> > diff --git a/lib/sg_pool.c b/lib/sg_pool.c
> > index 6dd30615a201..e2cf548b9610 100644
> > --- a/lib/sg_pool.c
> > +++ b/lib/sg_pool.c
> > @@ -1,4 +1,4 @@
> > -#include <linux/module.h>
> > +#include <linux/init.h>
> > #include <linux/scatterlist.h>
> > #include <linux/mempool.h>
> > #include <linux/slab.h>
> > @@ -156,17 +156,4 @@ cleanup_sdb:
> >
> > return -ENOMEM;
> > }
> > -
> > -static __exit void sg_pool_exit(void)
> > -{
> > - int i;
> > -
> > - for (i = 0; i < SG_MEMPOOL_NR; i++) {
> > - struct sg_pool *sgp = sg_pools + i;
> > - mempool_destroy(sgp->pool);
> > - kmem_cache_destroy(sgp->slab);
> > - }
> > -}
> > -
> > -module_init(sg_pool_init);
> > -module_exit(sg_pool_exit);
> > +device_initcall(sg_pool_init);
>
> For SCSI it's OK because always CONFIG_SCSI=y
>
> But we may have a kernel .config with !CONFIG_SCSI and other
> non-block-device driver may use this sg_pool.
>
> So the .config will have CONFIG_SG_POOL=m

That is impossible currently, since as per above, the variable is bool
and not tristate. Did you mean to make it tristate?

Paul.
--

>
>
>
>

2016-04-21 04:23:59

by Ming Lin

[permalink] [raw]
Subject: Re: [PATCH] lib: make sg_pool explicitly non-modular

On Wed, 2016-04-20 at 23:02 -0400, Paul Gortmaker wrote:

> >
> > So the .config will have CONFIG_SG_POOL=m
>
> That is impossible currently, since as per above, the variable is
> bool
> and not tristate.  Did you mean to make it tristate?

I didn't notice that.

Yes, it should be tristate.