[21/94] radix tree test suite: Enhancements for Maple Tree
diff mbox series

Message ID 20210428153542.2814175-22-Liam.Howlett@Oracle.com
State New, archived
Headers show
Series
  • Introducing the Maple Tree
Related show

Commit Message

Liam Howlett April 28, 2021, 3:35 p.m. UTC
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---
 tools/testing/radix-tree/linux.c        | 16 +++++++++++++++-
 tools/testing/radix-tree/linux/kernel.h |  1 +
 2 files changed, 16 insertions(+), 1 deletion(-)

Comments

Suren Baghdasaryan May 28, 2021, 5:30 p.m. UTC | #1
On Wed, Apr 28, 2021 at 8:36 AM Liam Howlett <liam.howlett@oracle.com> wrote:
>

I know you have v2 for the first part of this patchset, I'm just going
over the whole thing... There should be some description here of what
the new struct member and new function are for. Ideally you would also
split it in two because it introduces two seemingly independent
additions: non_kernel and kmem_cache_get_alloc.

> Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
> ---
>  tools/testing/radix-tree/linux.c        | 16 +++++++++++++++-
>  tools/testing/radix-tree/linux/kernel.h |  1 +
>  2 files changed, 16 insertions(+), 1 deletion(-)
>
> diff --git a/tools/testing/radix-tree/linux.c b/tools/testing/radix-tree/linux.c
> index 2d9c59df60de..93f7de81fbe8 100644
> --- a/tools/testing/radix-tree/linux.c
> +++ b/tools/testing/radix-tree/linux.c
> @@ -24,15 +24,28 @@ struct kmem_cache {
>         int nr_objs;
>         void *objs;
>         void (*ctor)(void *);
> +       unsigned int non_kernel;
>  };
>
> +void kmem_cache_set_non_kernel(struct kmem_cache *cachep, unsigned int val)
> +{
> +       cachep->non_kernel = val;
> +}
> +
> +unsigned long kmem_cache_get_alloc(struct kmem_cache *cachep)
> +{
> +       return cachep->size * nr_allocated;

IIUC nr_allocated is incremented/decremented every time memory is
allocated/freed from *any* kmem_cache. Each kmem_cache has its own
size. So, nr_allocated counts allocated objects of potentially
different sizes. If that is so then I'm unclear what the result of
this multiplication would represent.

> +}
>  void *kmem_cache_alloc(struct kmem_cache *cachep, int gfp)
>  {
>         void *p;
>
> -       if (!(gfp & __GFP_DIRECT_RECLAIM))
> +       if (!(gfp & __GFP_DIRECT_RECLAIM) && !cachep->non_kernel)
>                 return NULL;
>
> +       if (!(gfp & __GFP_DIRECT_RECLAIM))
> +               cachep->non_kernel--;
> +
>         pthread_mutex_lock(&cachep->lock);
>         if (cachep->nr_objs) {
>                 struct radix_tree_node *node = cachep->objs;
> @@ -116,5 +129,6 @@ kmem_cache_create(const char *name, unsigned int size, unsigned int align,
>         ret->nr_objs = 0;
>         ret->objs = NULL;
>         ret->ctor = ctor;
> +       ret->non_kernel = 0;
>         return ret;
>  }
> diff --git a/tools/testing/radix-tree/linux/kernel.h b/tools/testing/radix-tree/linux/kernel.h
> index 39867fd80c8f..c5c9d05f29da 100644
> --- a/tools/testing/radix-tree/linux/kernel.h
> +++ b/tools/testing/radix-tree/linux/kernel.h
> @@ -14,6 +14,7 @@
>  #include "../../../include/linux/kconfig.h"
>
>  #define printk printf
> +#define pr_err printk
>  #define pr_info printk
>  #define pr_debug printk
>  #define pr_cont printk
> --
> 2.30.2
Liam Howlett May 28, 2021, 6:54 p.m. UTC | #2
* Suren Baghdasaryan <surenb@google.com> [210528 13:31]:
> On Wed, Apr 28, 2021 at 8:36 AM Liam Howlett <liam.howlett@oracle.com> wrote:
> >
> 
> I know you have v2 for the first part of this patchset, I'm just going
> over the whole thing... There should be some description here of what
> the new struct member and new function are for. Ideally you would also
> split it in two because it introduces two seemingly independent
> additions: non_kernel and kmem_cache_get_alloc.

Your comments are still valid and appreciated.

I did add a description to the patch:
--------------------------------
radix tree test suite: Add kmem_cache enhancements and pr_err

Add kmem_cache_set_non_kernel(), a mechanism to allow a certain number
of kmem_cache_alloc requests to succeed even when GFP_KERNEL is not set
in the flags.

Add kmem_cache_get_alloc() to see the size of the allocated kmem_cache.

Add a define of pr_err to printk.
--------------------------------

I did group these two changes together as they were both affecting
kmem_cache.  I will reorganize them into separate commits.

> 
> > Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
> > Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
> > ---
> >  tools/testing/radix-tree/linux.c        | 16 +++++++++++++++-
> >  tools/testing/radix-tree/linux/kernel.h |  1 +
> >  2 files changed, 16 insertions(+), 1 deletion(-)
> >
> > diff --git a/tools/testing/radix-tree/linux.c b/tools/testing/radix-tree/linux.c
> > index 2d9c59df60de..93f7de81fbe8 100644
> > --- a/tools/testing/radix-tree/linux.c
> > +++ b/tools/testing/radix-tree/linux.c
> > @@ -24,15 +24,28 @@ struct kmem_cache {
> >         int nr_objs;
> >         void *objs;
> >         void (*ctor)(void *);
> > +       unsigned int non_kernel;
> >  };
> >
> > +void kmem_cache_set_non_kernel(struct kmem_cache *cachep, unsigned int val)
> > +{
> > +       cachep->non_kernel = val;
> > +}
> > +
> > +unsigned long kmem_cache_get_alloc(struct kmem_cache *cachep)
> > +{
> > +       return cachep->size * nr_allocated;
> 
> IIUC nr_allocated is incremented/decremented every time memory is
> allocated/freed from *any* kmem_cache. Each kmem_cache has its own
> size. So, nr_allocated counts allocated objects of potentially
> different sizes. If that is so then I'm unclear what the result of
> this multiplication would represent.

This is intended to only be used for testing with one kmem_cache, so it
hasn't been an issue.  Having this variable exist external to the
kmem_cache struct allows for checking if any allocations remain outside
the scope of the kmem_cache (ie: threads).  I think putting it in the
struct would cause issues with the IDR testing.  I could make this a new
variable and increment them together but this variable existed for the
IDR testing and I didn't need to support that additional functionality
for my testing.  I should at least add a comment about this limitation
though.

> 
> > +}
> >  void *kmem_cache_alloc(struct kmem_cache *cachep, int gfp)
> >  {
> >         void *p;
> >
> > -       if (!(gfp & __GFP_DIRECT_RECLAIM))
> > +       if (!(gfp & __GFP_DIRECT_RECLAIM) && !cachep->non_kernel)
> >                 return NULL;
> >
> > +       if (!(gfp & __GFP_DIRECT_RECLAIM))
> > +               cachep->non_kernel--;
> > +
> >         pthread_mutex_lock(&cachep->lock);
> >         if (cachep->nr_objs) {
> >                 struct radix_tree_node *node = cachep->objs;
> > @@ -116,5 +129,6 @@ kmem_cache_create(const char *name, unsigned int size, unsigned int align,
> >         ret->nr_objs = 0;
> >         ret->objs = NULL;
> >         ret->ctor = ctor;
> > +       ret->non_kernel = 0;
> >         return ret;
> >  }
> > diff --git a/tools/testing/radix-tree/linux/kernel.h b/tools/testing/radix-tree/linux/kernel.h
> > index 39867fd80c8f..c5c9d05f29da 100644
> > --- a/tools/testing/radix-tree/linux/kernel.h
> > +++ b/tools/testing/radix-tree/linux/kernel.h
> > @@ -14,6 +14,7 @@
> >  #include "../../../include/linux/kconfig.h"
> >
> >  #define printk printf
> > +#define pr_err printk
> >  #define pr_info printk
> >  #define pr_debug printk
> >  #define pr_cont printk
> > --
> > 2.30.2

Patch
diff mbox series

diff --git a/tools/testing/radix-tree/linux.c b/tools/testing/radix-tree/linux.c
index 2d9c59df60de..93f7de81fbe8 100644
--- a/tools/testing/radix-tree/linux.c
+++ b/tools/testing/radix-tree/linux.c
@@ -24,15 +24,28 @@  struct kmem_cache {
 	int nr_objs;
 	void *objs;
 	void (*ctor)(void *);
+	unsigned int non_kernel;
 };
 
+void kmem_cache_set_non_kernel(struct kmem_cache *cachep, unsigned int val)
+{
+	cachep->non_kernel = val;
+}
+
+unsigned long kmem_cache_get_alloc(struct kmem_cache *cachep)
+{
+	return cachep->size * nr_allocated;
+}
 void *kmem_cache_alloc(struct kmem_cache *cachep, int gfp)
 {
 	void *p;
 
-	if (!(gfp & __GFP_DIRECT_RECLAIM))
+	if (!(gfp & __GFP_DIRECT_RECLAIM) && !cachep->non_kernel)
 		return NULL;
 
+	if (!(gfp & __GFP_DIRECT_RECLAIM))
+		cachep->non_kernel--;
+
 	pthread_mutex_lock(&cachep->lock);
 	if (cachep->nr_objs) {
 		struct radix_tree_node *node = cachep->objs;
@@ -116,5 +129,6 @@  kmem_cache_create(const char *name, unsigned int size, unsigned int align,
 	ret->nr_objs = 0;
 	ret->objs = NULL;
 	ret->ctor = ctor;
+	ret->non_kernel = 0;
 	return ret;
 }
diff --git a/tools/testing/radix-tree/linux/kernel.h b/tools/testing/radix-tree/linux/kernel.h
index 39867fd80c8f..c5c9d05f29da 100644
--- a/tools/testing/radix-tree/linux/kernel.h
+++ b/tools/testing/radix-tree/linux/kernel.h
@@ -14,6 +14,7 @@ 
 #include "../../../include/linux/kconfig.h"
 
 #define printk printf
+#define pr_err printk
 #define pr_info printk
 #define pr_debug printk
 #define pr_cont printk