[thirdparty/git.git] / parallel-checkout.h

#ifndef PARALLEL_CHECKOUT_H
#define PARALLEL_CHECKOUT_H

#include "convert.h"

struct cache_entry;
struct checkout;
struct progress;

/****************************************************************
 * Users of parallel checkout
 ****************************************************************/

enum pc_status {
	PC_UNINITIALIZED = 0,
	PC_ACCEPTING_ENTRIES,
	PC_RUNNING,
};

enum pc_status parallel_checkout_status(void);
void get_parallel_checkout_configs(int *num_workers, int *threshold);

/*
 * Put parallel checkout into the PC_ACCEPTING_ENTRIES state. Should be used
 * only when in the PC_UNINITIALIZED state.
 */
void init_parallel_checkout(void);

/*
 * Return -1 if parallel checkout is currently not accepting entries or if the
 * entry is not eligible for parallel checkout. Otherwise, enqueue the entry
 * for later write and return 0.
 */
int enqueue_checkout(struct cache_entry *ce, struct conv_attrs *ca);
size_t pc_queue_size(void);

/*
 * Write all the queued entries, returning 0 on success. If the number of
 * entries is smaller than the specified threshold, the operation is performed
 * sequentially.
 */
int run_parallel_checkout(struct checkout *state, int num_workers, int threshold,
			  struct progress *progress, unsigned int *progress_cnt);

/****************************************************************
 * Interface with checkout--worker
 ****************************************************************/

enum pc_item_status {
	PC_ITEM_PENDING = 0,
	PC_ITEM_WRITTEN,
	/*
	 * The entry could not be written because there was another file
	 * already present in its path or leading directories. Since
	 * checkout_entry_ca() removes such files from the working tree before
	 * enqueueing the entry for parallel checkout, it means that there was
	 * a path collision among the entries being written.
	 */
	PC_ITEM_COLLIDED,
	PC_ITEM_FAILED,
};

struct parallel_checkout_item {
	/*
	 * In main process ce points to a istate->cache[] entry. Thus, it's not
	 * owned by us. In workers they own the memory, which *must be* released.
	 */
	struct cache_entry *ce;
	struct conv_attrs ca;
	size_t id; /* position in parallel_checkout.items[] of main process */

	/* Output fields, sent from workers. */
	enum pc_item_status status;
	struct stat st;
};

/*
 * The fixed-size portion of `struct parallel_checkout_item` that is sent to the
 * workers. Following this will be 2 strings: ca.working_tree_encoding and
 * ce.name; These are NOT null terminated, since we have the size in the fixed
 * portion.
 *
 * Note that not all fields of conv_attrs and cache_entry are passed, only the
 * ones that will be required by the workers to smudge and write the entry.
 */
struct pc_item_fixed_portion {
	size_t id;
	struct object_id oid;
	unsigned int ce_mode;
	enum convert_crlf_action crlf_action;
	int ident;
	size_t working_tree_encoding_len;
	size_t name_len;
};

/*
 * The fields of `struct parallel_checkout_item` that are returned by the
 * workers. Note: `st` must be the last one, as it is omitted on error.
 */
struct pc_item_result {
	size_t id;
	enum pc_item_status status;
	struct stat st;
};

#define PC_ITEM_RESULT_BASE_SIZE offsetof(struct pc_item_result, st)

void write_pc_item(struct parallel_checkout_item *pc_item,
		   struct checkout *state);

#endif /* PARALLEL_CHECKOUT_H */
Commit	Line	Data
04155bda MT	1	#ifndef PARALLEL_CHECKOUT_H
	2	#define PARALLEL_CHECKOUT_H
	3
e9e8adf1 MT	4	#include "convert.h"
e9e8adf1 MT	5
04155bda MT	6	struct cache_entry;
04155bda MT	7	struct checkout;
1c4d6f46	8	struct progress;
e9e8adf1 MT	9
	10	/****************************************************************
	11	* Users of parallel checkout
	12	****************************************************************/
04155bda MT	13
	14	enum pc_status {
	15	PC_UNINITIALIZED = 0,
	16	PC_ACCEPTING_ENTRIES,
	17	PC_RUNNING,
	18	};
	19
	20	enum pc_status parallel_checkout_status(void);
7531e4b6	21	void get_parallel_checkout_configs(int num_workers, int threshold);
04155bda MT	22
	23	/*
	24	* Put parallel checkout into the PC_ACCEPTING_ENTRIES state. Should be used
	25	* only when in the PC_UNINITIALIZED state.
	26	*/
	27	void init_parallel_checkout(void);
	28
	29	/*
	30	* Return -1 if parallel checkout is currently not accepting entries or if the
	31	* entry is not eligible for parallel checkout. Otherwise, enqueue the entry
	32	* for later write and return 0.
	33	*/
	34	int enqueue_checkout(struct cache_entry ce, struct conv_attrs ca);
1c4d6f46	35	size_t pc_queue_size(void);
04155bda	36
7531e4b6 MT	37	/*
	38	* Write all the queued entries, returning 0 on success. If the number of
	39	* entries is smaller than the specified threshold, the operation is performed
	40	* sequentially.
	41	*/
1c4d6f46 MT	42	int run_parallel_checkout(struct checkout *state, int num_workers, int threshold,
1c4d6f46 MT	43	struct progress progress, unsigned int progress_cnt);
04155bda	44
e9e8adf1 MT	45	/****************************************************************
	46	* Interface with checkout--worker
	47	****************************************************************/
	48
	49	enum pc_item_status {
	50	PC_ITEM_PENDING = 0,
	51	PC_ITEM_WRITTEN,
	52	/*
	53	* The entry could not be written because there was another file
	54	* already present in its path or leading directories. Since
	55	* checkout_entry_ca() removes such files from the working tree before
	56	* enqueueing the entry for parallel checkout, it means that there was
	57	* a path collision among the entries being written.
	58	*/
	59	PC_ITEM_COLLIDED,
	60	PC_ITEM_FAILED,
	61	};
	62
	63	struct parallel_checkout_item {
	64	/*
	65	* In main process ce points to a istate->cache[] entry. Thus, it's not
	66	* owned by us. In workers they own the memory, which must be released.
	67	*/
	68	struct cache_entry *ce;
	69	struct conv_attrs ca;
	70	size_t id; /* position in parallel_checkout.items[] of main process */
	71
	72	/* Output fields, sent from workers. */
	73	enum pc_item_status status;
	74	struct stat st;
	75	};
	76
	77	/*
	78	* The fixed-size portion of `struct parallel_checkout_item` that is sent to the
	79	* workers. Following this will be 2 strings: ca.working_tree_encoding and
	80	* ce.name; These are NOT null terminated, since we have the size in the fixed
	81	* portion.
	82	*
	83	* Note that not all fields of conv_attrs and cache_entry are passed, only the
	84	* ones that will be required by the workers to smudge and write the entry.
	85	*/
	86	struct pc_item_fixed_portion {
	87	size_t id;
	88	struct object_id oid;
	89	unsigned int ce_mode;
	90	enum convert_crlf_action crlf_action;
	91	int ident;
	92	size_t working_tree_encoding_len;
	93	size_t name_len;
	94	};
	95
	96	/*
	97	* The fields of `struct parallel_checkout_item` that are returned by the
	98	* workers. Note: `st` must be the last one, as it is omitted on error.
	99	*/
	100	struct pc_item_result {
	101	size_t id;
	102	enum pc_item_status status;
	103	struct stat st;
	104	};
	105
	106	#define PC_ITEM_RESULT_BASE_SIZE offsetof(struct pc_item_result, st)
	107
	108	void write_pc_item(struct parallel_checkout_item *pc_item,
109	struct checkout *state);
110
04155bda	111	#endif /* PARALLEL_CHECKOUT_H */