Commit 9c27d729 authored by Tom Burdick's avatar Tom Burdick Committed by Benjamin Cabé
Browse files

rtio: Add a context pool 

Adds a context pool that can be used when a number of threads may be
dynamically created to use with RTIO. While the pool has a small cost to
it, the cost of verifying a statically declared kobject likely makes it
worth avoiding dynamically allocating these with the typical
kobject_alloc method. Instead this arena style pool of objects can be
used where the kobject validation uses the gperf hash created at build
time.

Signed-off-by: default avatarTom Burdick <thomas.burdick@intel.com>
parent 80ab4b81

include/zephyr/linker/common-ram.ld

+1 −0
Changes for include/zephyr/linker/common-ram.ld: 1 added line, 0 removed lines.
Original line number Diff line number Diff line
@@ -126,6 +126,7 @@ ITERABLE_SECTION_RAM(scmi_protocol, Z_LINK_ITERABLE_SUBALIGN) 


#if defined(CONFIG_RTIO)

	ITERABLE_SECTION_RAM(rtio, Z_LINK_ITERABLE_SUBALIGN)

	ITERABLE_SECTION_RAM(rtio_pool, Z_LINK_ITERABLE_SUBALIGN)

	ITERABLE_SECTION_RAM(rtio_iodev, Z_LINK_ITERABLE_SUBALIGN)

	ITERABLE_SECTION_RAM(rtio_sqe_pool, Z_LINK_ITERABLE_SUBALIGN)

	ITERABLE_SECTION_RAM(rtio_cqe_pool, Z_LINK_ITERABLE_SUBALIGN)

include/zephyr/rtio/rtio.h

+125 −0
Changes for include/zephyr/rtio/rtio.h: 125 added lines, 0 removed lines.
Original line number Diff line number Diff line
@@ -1421,6 +1421,9 @@ static inline void z_impl_rtio_release_buffer(struct rtio *r, void *buff, uint32 


/**

 * Grant access to an RTIO context to a user thread

 *

 * @param r RTIO context

 * @param t Thread to grant permissions to

 */

static inline void rtio_access_grant(struct rtio *r, struct k_thread *t)

{
@@ -1435,6 +1438,26 @@ static inline void rtio_access_grant(struct rtio *r, struct k_thread *t) 
#endif

}





/**

 * Revoke access to an RTIO context from a user thread

 *

 * @param r RTIO context

 * @param t Thread to revoke permissions from

 */

static inline void rtio_access_revoke(struct rtio *r, struct k_thread *t)

{

	k_object_access_revoke(r, t);



#ifdef CONFIG_RTIO_SUBMIT_SEM

	k_object_access_revoke(r->submit_sem, t);

#endif



#ifdef CONFIG_RTIO_CONSUME_SEM

	k_object_access_revoke(r->consume_sem, t);

#endif

}



/**

 * @brief Attempt to cancel an SQE

 *
@@ -1674,6 +1697,108 @@ static inline int z_impl_rtio_submit(struct rtio *r, uint32_t wait_count) 
}

#endif /* CONFIG_RTIO_SUBMIT_SEM */



/**

 * @brief Pool of RTIO contexts to use with dynamically created threads

 */

struct rtio_pool {

	/** Size of the pool */

	size_t pool_size;



	/** Array containing contexts of the pool */

	struct rtio **contexts;



	/** Atomic bitmap to signal a member is used/unused */

	atomic_t *used;

};



/**

 * @brief Obtain an RTIO context from a pool

 *

 * @param pool RTIO pool to acquire a context from

 *

 * @retval NULL no available contexts

 * @retval r Valid context with permissions granted to the calling thread

 */

__syscall struct rtio *rtio_pool_acquire(struct rtio_pool *pool);



static inline struct rtio *z_impl_rtio_pool_acquire(struct rtio_pool *pool)

{

	struct rtio *r = NULL;



	for (size_t i = 0; i < pool->pool_size; i++) {

		if (atomic_test_and_set_bit(pool->used, i) == 0) {

			r = pool->contexts[i];

			break;

		}

	}



	if (r != NULL) {

		rtio_access_grant(r, k_current_get());

	}



	return r;

}



/**

 * @brief Return an RTIO context to a pool

 *

 * @param pool RTIO pool to return a context to

 * @param r RTIO context to return to the pool

 */

__syscall void rtio_pool_release(struct rtio_pool *pool, struct rtio *r);



static inline void z_impl_rtio_pool_release(struct rtio_pool *pool, struct rtio *r)

{



	if (k_is_user_context()) {

		rtio_access_revoke(r, k_current_get());

	}



	for (size_t i = 0; i < pool->pool_size; i++) {

		if (pool->contexts[i] == r) {

			atomic_clear_bit(pool->used, i);

			break;

		}

	}

}



/* clang-format off */



/** @cond ignore */



#define Z_RTIO_POOL_NAME_N(n, name)                                             \

	name##_##n



#define Z_RTIO_POOL_DEFINE_N(n, name, sq_sz, cq_sz)				\

	RTIO_DEFINE(Z_RTIO_POOL_NAME_N(n, name), sq_sz, cq_sz)



#define Z_RTIO_POOL_REF_N(n, name)                                              \

	&Z_RTIO_POOL_NAME_N(n, name)



/** @endcond */



/**

 * @brief Statically define and initialize a pool of RTIO contexts

 *

 * @param name Name of the RTIO pool

 * @param pool_sz Number of RTIO contexts to allocate in the pool

 * @param sq_sz Size of the submission queue entry pool per context

 * @param cq_sz Size of the completion queue entry pool per context

 */

#define RTIO_POOL_DEFINE(name, pool_sz, sq_sz, cq_sz)				\

	LISTIFY(pool_sz, Z_RTIO_POOL_DEFINE_N, (;), name, sq_sz, cq_sz);        \

	static struct rtio *name##_contexts[] = {                               \

		LISTIFY(pool_sz, Z_RTIO_POOL_REF_N, (,), name)                  \

	};                                                                      \

	ATOMIC_DEFINE(name##_used, pool_sz);                                    \

	STRUCT_SECTION_ITERABLE(rtio_pool, name) = {                            \

		.pool_size = pool_sz,                                           \

		.contexts = name##_contexts,                                    \

		.used = name##_used,                                            \

	}



/* clang-format on */



/**

 * @}

 */

scripts/build/gen_kobject_list.py

+1 −0
Changes for scripts/build/gen_kobject_list.py: 1 added line, 0 removed lines.
Original line number Diff line number Diff line
@@ -114,6 +114,7 @@ kobjects = OrderedDict([ 
    ("ztest_test_rule", ("CONFIG_ZTEST", True, False)),

    ("rtio", ("CONFIG_RTIO", False, False)),

    ("rtio_iodev", ("CONFIG_RTIO", False, False)),

    ("rtio_pool", ("CONFIG_RTIO", False, False)),

    ("sensor_decoder_api", ("CONFIG_SENSOR_ASYNC_API", True, False))

])

subsys/rtio/CMakeLists.txt

+1 −1
Changes for subsys/rtio/CMakeLists.txt: 1 added line, 1 removed line.
Original line number Diff line number Diff line
@@ -11,7 +11,7 @@ if(CONFIG_RTIO) 
	zephyr_library_sources(rtio_executor.c)

	zephyr_library_sources(rtio_init.c)

	zephyr_library_sources(rtio_sched.c)

	zephyr_library_sources_ifdef(CONFIG_USERSPACE rtio_handlers.c)

	zephyr_library_sources_ifdef(CONFIG_USERSPACE rtio_syscalls.c)

endif()



zephyr_library_sources_ifdef(CONFIG_RTIO_WORKQ rtio_workq.c)

subsys/rtio/rtio_handlers.c→subsys/rtio/rtio_syscalls.c

+19 −0
Changes for subsys/rtio/rtio_syscalls.c: 19 added lines, 0 removed lines.
Original line number Diff line number Diff line
@@ -135,3 +135,22 @@ static inline int z_vrfy_rtio_submit(struct rtio *r, uint32_t wait_count) 
	return z_impl_rtio_submit(r, wait_count);

}

#include <zephyr/syscalls/rtio_submit_mrsh.c>





static inline struct rtio *z_vrfy_rtio_pool_acquire(struct rtio_pool *rpool)

{

	K_OOPS(K_SYSCALL_OBJ(rpool, K_OBJ_RTIO_POOL));



	return z_impl_rtio_pool_acquire(rpool);

}

#include <zephyr/syscalls/rtio_pool_acquire_mrsh.c>





static inline void z_vrfy_rtio_pool_release(struct rtio_pool *rpool, struct rtio *r)

{

	K_OOPS(K_SYSCALL_OBJ(rpool, K_OBJ_RTIO_POOL));

	K_OOPS(K_SYSCALL_OBJ(r, K_OBJ_RTIO));



	z_impl_rtio_pool_release(rpool, r);

}

#include <zephyr/syscalls/rtio_pool_release_mrsh.c>

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