[PATCH libdrm 2/6] amdgpu: add handle table implementation v2

[Zhang, Jerry (Junwei)]

On 08/03/2018 07:34 PM, Christian König wrote:
> The kernel handles are dense and the kernel always tries to use the
> lowest free id. Use this to implement a more efficient handle table
> by using a resizeable array instead of a hash.
>
> v2: add handle_table_fini function, extra key checks,
>      fix typo in function name
>
> Signed-off-by: Christian König <christian.koenig at amd.com>
> ---
>   amdgpu/Makefile.sources |  4 ++-
>   amdgpu/handle_table.c   | 72 +++++++++++++++++++++++++++++++++++++++++++++++++
>   amdgpu/handle_table.h   | 41 ++++++++++++++++++++++++++++
>   3 files changed, 116 insertions(+), 1 deletion(-)
>   create mode 100644 amdgpu/handle_table.c
>   create mode 100644 amdgpu/handle_table.h
>
> diff --git a/amdgpu/Makefile.sources b/amdgpu/Makefile.sources
> index 498b64cc..62577ba5 100644
> --- a/amdgpu/Makefile.sources
> +++ b/amdgpu/Makefile.sources
> @@ -10,7 +10,9 @@ LIBDRM_AMDGPU_FILES := \
>   	util_hash.c \
>   	util_hash.h \
>   	util_hash_table.c \
> -	util_hash_table.h
> +	util_hash_table.h \
> +	handle_table.c \
> +	handle_table.h
>
>   LIBDRM_AMDGPU_H_FILES := \
>   	amdgpu.h
> diff --git a/amdgpu/handle_table.c b/amdgpu/handle_table.c
> new file mode 100644
> index 00000000..15cd4763
> --- /dev/null
> +++ b/amdgpu/handle_table.c
> @@ -0,0 +1,72 @@
> +/*
> + * Copyright 2018 Advanced Micro Devices, Inc.
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the "Software"),
> + * to deal in the Software without restriction, including without limitation
> + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
> + * and/or sell copies of the Software, and to permit persons to whom the
> + * Software is furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice shall be included in
> + * all copies or substantial portions of the Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
> + * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
> + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
> + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
> + * OTHER DEALINGS IN THE SOFTWARE.
> + *
> + */
> +
> +#include <stdlib.h>
> +#include <string.h>
> +#include <errno.h>
> +#include <unistd.h>
> +#include "handle_table.h"
> +#include "util_math.h"
> +
> +drm_private int handle_table_insert(struct handle_table *table, uint32_t key,
> +				    void *value)
> +{
> +	if (key >= table->max_key) {
> +		uint32_t alignment = sysconf(_SC_PAGESIZE) / sizeof(void*);
> +		uint32_t max_key = ALIGN(key, alignment);

On 2nd thought, we may add table->count to take the role of current table->max_key,
and table_max_key could be updated by key rather than aligned value.

Then we could traverse the table by max_key instead of the entire table.

Regards,
Jerry

> +		void **values;
> +
> +		values = realloc(table->values, max_key * sizeof(void *));
> +		if (!values)
> +			return -ENOMEM;
> +
> +		memset(values + table->max_key, 0, (max_key - table->max_key) *
> +		       sizeof(void *));
> +
> +		table->max_key = max_key;
> +		table->values = values;
> +	}
> +	table->values[key] = value;
> +	return 0;
> +}
> +
> +drm_private void handle_table_remove(struct handle_table *table, uint32_t key)
> +{
> +	if (key < table->max_key)
> +		table->values[key] = NULL;
> +}
> +
> +drm_private void *handle_table_lookup(struct handle_table *table, uint32_t key)
> +{
> +	if (key < table->max_key)
> +		return table->values[key];
> +	else
> +		return NULL;
> +}
> +
> +drm_private void handle_table_fini(struct handle_table *table)
> +{
> +	free(table->values);
> +	table->max_key = 0;
> +	table->values = NULL;
> +}
> diff --git a/amdgpu/handle_table.h b/amdgpu/handle_table.h
> new file mode 100644
> index 00000000..461193f6
> --- /dev/null
> +++ b/amdgpu/handle_table.h
> @@ -0,0 +1,41 @@
> +/*
> + * Copyright 2018 Advanced Micro Devices, Inc.
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the "Software"),
> + * to deal in the Software without restriction, including without limitation
> + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
> + * and/or sell copies of the Software, and to permit persons to whom the
> + * Software is furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice shall be included in
> + * all copies or substantial portions of the Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
> + * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
> + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
> + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
> + * OTHER DEALINGS IN THE SOFTWARE.
> + *
> + */
> +
> +#ifndef _HANDLE_TABLE_H_
> +#define _HANDLE_TABLE_H_
> +
> +#include <stdint.h>
> +#include "libdrm_macros.h"
> +
> +struct handle_table {
> +	uint32_t	max_key;
> +	void		**values;
> +};
> +
> +drm_private int handle_table_insert(struct handle_table *table, uint32_t key,
> +				    void *value);
> +drm_private void handle_table_remove(struct handle_table *table, uint32_t key);
> +drm_private void *handle_table_lookup(struct handle_table *table, uint32_t key);
> +drm_private void handle_table_fini(struct handle_table *table);
> +
> +#endif /* _HANDLE_TABLE_H_ */
>