Uses the workqueue/threadpool code to farm CPU-intensive activities out to subprocesses. More...

#include "core/or/or.h"
#include "core/or/channel.h"
#include "core/or/circuitlist.h"
#include "core/or/connection_or.h"
#include "core/or/congestion_control_common.h"
#include "core/or/congestion_control_flow.h"
#include "app/config/config.h"
#include "core/mainloop/cpuworker.h"
#include "lib/crypt_ops/crypto_rand.h"
#include "lib/crypt_ops/crypto_util.h"
#include "core/or/onion.h"
#include "feature/relay/circuitbuild_relay.h"
#include "feature/relay/onion_queue.h"
#include "feature/stats/rephist.h"
#include "feature/relay/router.h"
#include "feature/nodelist/networkstatus.h"
#include "lib/evloop/workqueue.h"
#include "core/crypto/onion_crypto.h"
#include "core/or/or_circuit_st.h"

Data Structures
struct	worker_state_t

struct	cpuworker_request_t

struct	cpuworker_reply_t

struct	cpuworker_job_t

Macros
#define	worker_state_free(ws) FREE_AND_NULL(worker_state_t, worker_state_free_, (ws))

#define	MAX_PENDING_TASKS_PER_CPU_DEFAULT 64

#define	MAX_PENDING_TASKS_PER_CPU_MIN 1

#define	MAX_PENDING_TASKS_PER_CPU_MAX INT32_MAX

#define	CPUWORKER_REQUEST_MAGIC 0xda4afeed

#define	CPUWORKER_REPLY_MAGIC 0x5eedf00d

#define	MAX_BELIEVABLE_ONIONSKIN_DELAY (210001000)

Functions
static void	queue_pending_tasks (void)

static void *	worker_state_new (void *arg)

static void	worker_state_free_ (worker_state_t *ws)

static void	worker_state_free_void (void *arg)

static uint32_t	get_max_pending_tasks_per_cpu (const networkstatus_t *ns)

static void	set_max_pending_tasks (const networkstatus_t *ns)

void	cpuworker_consensus_has_changed (const networkstatus_t *ns)

void	cpu_init (void)

unsigned int	cpuworker_get_n_threads (void)

static workqueue_reply_t	update_state_threadfn (void state_, void work_)

void	cpuworkers_rotate_keyinfo (void)

static int	should_time_request (uint16_t onionskin_type)

uint64_t	estimated_usec_for_onionskins (uint32_t n_requests, uint16_t onionskin_type)

static int	get_overhead_for_onionskins (uint32_t usec_out, double frac_out, uint16_t onionskin_type)

void	cpuworker_log_onionskin_overhead (int severity, int onionskin_type, const char *onionskin_type_name)

static void	cpuworker_onion_handshake_replyfn (void *work_)

static workqueue_reply_t	cpuworker_onion_handshake_threadfn (void state_, void work_)

workqueue_entry_t *	cpuworker_queue_work (workqueue_priority_t priority, workqueue_reply_t(fn)(void , void ), void(reply_fn)(void ), void arg)

int	assign_onionskin_to_cpuworker (or_circuit_t circ, create_cell_t onionskin)

void	cpuworker_cancel_circ_handshake (or_circuit_t *circ)

Variables
static replyqueue_t *	replyqueue = NULL

static threadpool_t *	threadpool = NULL

static uint32_t	total_pending_tasks = 0

static uint32_t	max_pending_tasks = 128

static uint64_t	onionskins_n_processed [MAX_ONION_HANDSHAKE_TYPE+1]

static uint64_t	onionskins_usec_internal [MAX_ONION_HANDSHAKE_TYPE+1]

static uint64_t	onionskins_usec_roundtrip [MAX_ONION_HANDSHAKE_TYPE+1]

Detailed Description

Uses the workqueue/threadpool code to farm CPU-intensive activities out to subprocesses.

The multithreading backend for this module is in workqueue.c; this module specializes workqueue.c.

Right now, we use this infrastructure

for processing onionskins in onion.c
for compressing consensuses in consdiffmgr.c,
and for calculating diffs and compressing them in consdiffmgr.c.

Definition in file cpuworker.c.

Macro Definition Documentation

◆ CPUWORKER_REQUEST_MAGIC

#define CPUWORKER_REQUEST_MAGIC 0xda4afeed

Magic numbers to make sure our cpuworker_requests don't grow any mis-framing bugs.

Definition at line 159 of file cpuworker.c.

◆ MAX_BELIEVABLE_ONIONSKIN_DELAY

#define MAX_BELIEVABLE_ONIONSKIN_DELAY (2*1000*1000)

If any onionskin takes longer than this, we clip them to this time. (microseconds)

Definition at line 273 of file cpuworker.c.

Function Documentation

◆ assign_onionskin_to_cpuworker()

int assign_onionskin_to_cpuworker	(	or_circuit_t *	circ,
		create_cell_t *	onionskin
	)

Try to tell a cpuworker to perform the public key operations necessary to respond to onionskin for the circuit circ.

Return 0 if we successfully assign the task, or -1 on failure.

Definition at line 583 of file cpuworker.c.

◆ cpu_init()

void cpu_init ( void )

Initialize the cpuworker subsystem. It is OK to call this more than once during Tor's lifetime.

Definition at line 120 of file cpuworker.c.

◆ cpuworker_cancel_circ_handshake()

void cpuworker_cancel_circ_handshake ( or_circuit_t * circ )

If circ has a pending handshake that hasn't been processed yet, remove it from the worker queue.

Definition at line 656 of file cpuworker.c.

Referenced by onion_pending_remove().

◆ cpuworker_consensus_has_changed()

void cpuworker_consensus_has_changed ( const networkstatus_t * ns )

Called when the consensus has changed.

Definition at line 110 of file cpuworker.c.

◆ cpuworker_get_n_threads()

unsigned int cpuworker_get_n_threads ( void )

Return the number of threads configured for our CPU worker.

Definition at line 149 of file cpuworker.c.

◆ cpuworker_log_onionskin_overhead()

void cpuworker_log_onionskin_overhead	(	int	severity,
		int	onionskin_type,
		const char *	onionskin_type_name
	)

If we've measured overhead for onionskins of type onionskin_type, log it.

Definition at line 345 of file cpuworker.c.

◆ cpuworker_onion_handshake_replyfn()

static void cpuworker_onion_handshake_replyfn ( void * work_ )

static

Handle a reply from the worker threads.

Definition at line 365 of file cpuworker.c.

◆ cpuworker_onion_handshake_threadfn()

static workqueue_reply_t cpuworker_onion_handshake_threadfn	(	void *	state_,
		void *	work_
	)

static

Implementation function for onion handshake requests.

Definition at line 467 of file cpuworker.c.

◆ cpuworker_queue_work()

workqueue_entry_t* cpuworker_queue_work	(	workqueue_priority_t	priority,
		workqueue_reply_t()(void , void *)	fn,
		void()(void )	reply_fn,
		void *	arg
	)

DOCDOC

Definition at line 566 of file cpuworker.c.

◆ cpuworkers_rotate_keyinfo()

void cpuworkers_rotate_keyinfo ( void )

Called when the onion key has changed so update all CPU worker(s) with new function pointers with which a new state will be generated.

Definition at line 241 of file cpuworker.c.

◆ estimated_usec_for_onionskins()

uint64_t estimated_usec_for_onionskins	(	uint32_t	n_requests,
		uint16_t	onionskin_type
	)

Return an estimate of how many microseconds we will need for a single cpuworker to process n_requests onionskins of type onionskin_type.

Definition at line 297 of file cpuworker.c.

◆ get_max_pending_tasks_per_cpu()

static uint32_t get_max_pending_tasks_per_cpu ( const networkstatus_t * ns )

static

Return the consensus parameter max pending tasks per CPU.

Definition at line 84 of file cpuworker.c.

◆ get_overhead_for_onionskins()

static int get_overhead_for_onionskins	(	uint32_t *	usec_out,
		double *	frac_out,
		uint16_t	onionskin_type
	)

static

Compute the absolute and relative overhead of using the cpuworker framework for onionskins of type onionskin_type.

Definition at line 318 of file cpuworker.c.

Referenced by cpuworker_log_onionskin_overhead().

◆ queue_pending_tasks()

static void queue_pending_tasks ( void )

static

Take pending tasks from the queue and assign them to cpuworkers.

Definition at line 545 of file cpuworker.c.

◆ set_max_pending_tasks()

static void set_max_pending_tasks ( const networkstatus_t * ns )

static

Set the max pending tasks per CPU worker. This uses the consensus to check for the allowed number per CPU. The ns parameter can be NULL as in that no consensus is available at the time of setting this value.

Definition at line 102 of file cpuworker.c.

Referenced by cpuworker_consensus_has_changed().

◆ should_time_request()

static int should_time_request ( uint16_t onionskin_type )

static

Return true iff we'd like to measure a handshake of type onionskin_type. Call only from the main thread.

Otherwise, measure with P=1/128. We avoid doing this for every handshake, since the measurement itself can take a little time.

Definition at line 278 of file cpuworker.c.

Variable Documentation

◆ onionskins_n_processed

uint64_t onionskins_n_processed[MAX_ONION_HANDSHAKE_TYPE+1]

static

Indexed by handshake type: how many onionskins have we processed and counted of that type?

Definition at line 260 of file cpuworker.c.

◆ onionskins_usec_internal

uint64_t onionskins_usec_internal[MAX_ONION_HANDSHAKE_TYPE+1]

static

Indexed by handshake type, corresponding to the onionskins counted in onionskins_n_processed: how many microseconds have we spent in cpuworkers processing that kind of onionskin?

Definition at line 264 of file cpuworker.c.

◆ onionskins_usec_roundtrip

uint64_t onionskins_usec_roundtrip[MAX_ONION_HANDSHAKE_TYPE+1]

static

Indexed by handshake type, corresponding to onionskins counted in onionskins_n_processed: how many microseconds have we spent waiting for cpuworkers to give us answers for that kind of onionskin?

Definition at line 269 of file cpuworker.c.

Data Structures

Macros

Functions

Variables

Detailed Description

Macro Definition Documentation

◆ CPUWORKER_REQUEST_MAGIC

◆ MAX_BELIEVABLE_ONIONSKIN_DELAY

Function Documentation

◆ assign_onionskin_to_cpuworker()

◆ cpu_init()

◆ cpuworker_cancel_circ_handshake()

◆ cpuworker_consensus_has_changed()

◆ cpuworker_get_n_threads()

◆ cpuworker_log_onionskin_overhead()

◆ cpuworker_onion_handshake_replyfn()

◆ cpuworker_onion_handshake_threadfn()

◆ cpuworker_queue_work()

◆ cpuworkers_rotate_keyinfo()

◆ estimated_usec_for_onionskins()

◆ get_max_pending_tasks_per_cpu()

◆ get_overhead_for_onionskins()

◆ queue_pending_tasks()

◆ set_max_pending_tasks()

◆ should_time_request()

Variable Documentation

◆ onionskins_n_processed

◆ onionskins_usec_internal

◆ onionskins_usec_roundtrip