Line data Source code
1 : #include "fd_sysvar_clock.h"
2 : #include "fd_sysvar_epoch_schedule.h"
3 : #include "../fd_runtime_stack.h"
4 : #include "../fd_system_ids.h"
5 : #include "../sysvar/fd_sysvar.h"
6 :
7 : /* Syvar Clock Possible Values:
8 : slot:
9 : [0, ULONG_MAX]
10 :
11 : epoch:
12 : [0, slot/432000UL]
13 :
14 : epoch_start_timestamp:
15 : [0, ULONG_MAX]
16 :
17 : unix_timestamp:
18 : This value is bounded by the slot distance from the
19 : epoch_start_timestamp.
20 : The protocol allows for a maximum drift (either fast or slow) from the
21 : start of the epoch's timestamp. The expected time is called the PoH
22 : offset. This offset is calculated by (epoch_start_timestamp + slots
23 : since epoch * slot_duration). The drift is then bounded by the
24 : max_allowable_drift_{slow,fast}. The stake weighted offset can be
25 : 150% more than the PoH offset and 25% less than the PoH offset.
26 : So, the bounds for the unix_timestamp can be calculated by:
27 : upper bound = epoch_start_timestamp + (slots since epoch * slot_duration) * 2.5
28 : lower bound = epoch_start_timestamp + (slots since epoch * slot_duration) * 0.75
29 :
30 : leader_schedule_epoch:
31 : This is the value of the epoch used for the leader schedule. It is
32 : computed based on the values of the epoch schedule (first_normal_slot,
33 : leader_schedule_slot_offset, slots_per_epoch). It is always equal to
34 : ((slot - first_normal_slot) + leader_schedule_slot_offset) / schedule->slots_per_epoch
35 : */
36 :
37 : /* https://github.com/anza-xyz/agave/blob/v2.3.7/runtime/src/stake_weighted_timestamp.rs#L14 */
38 4077 : #define MAX_ALLOWABLE_DRIFT_FAST_PERCENT ( 25U )
39 :
40 : /* https://github.com/anza-xyz/agave/blob/v2.3.7/runtime/src/stake_weighted_timestamp.rs#L15 */
41 4077 : #define MAX_ALLOWABLE_DRIFT_SLOW_PERCENT ( 150U )
42 :
43 : /* Do all intermediate calculations at nanosecond precision, to mirror
44 : Solana's behavior. */
45 15702 : #define NS_IN_S ((long)1e9)
46 :
47 : /* https://github.com/anza-xyz/agave/blob/v2.3.7/runtime/src/bank.rs#L2110-L2117 */
48 : static inline long
49 6 : unix_timestamp_from_genesis( fd_bank_t * bank ) {
50 : /* TODO: genesis_creation_time needs to be a long in the bank. */
51 6 : return fd_long_sat_add(
52 6 : (long)bank->f.genesis_creation_time,
53 6 : (long)( fd_uint128_sat_mul( bank->f.slot, bank->f.slot_params.ns_per_slot ) / NS_IN_S ) );
54 6 : }
55 :
56 : static void
57 : fd_sysvar_clock_write( fd_bank_t * bank,
58 : fd_accdb_t * accdb,
59 : fd_capture_ctx_t * capture_ctx,
60 4524 : fd_sol_sysvar_clock_t const * clock ) {
61 4524 : fd_sysvar_account_update( bank, accdb, capture_ctx, &fd_sysvar_clock_id, clock, sizeof(fd_sol_sysvar_clock_t) );
62 4524 : }
63 :
64 : fd_sol_sysvar_clock_t *
65 : fd_sysvar_clock_read( fd_accdb_t * accdb,
66 : fd_accdb_fork_id_t fork_id,
67 4533 : fd_sol_sysvar_clock_t * clock ) {
68 4533 : fd_acc_t acc = fd_accdb_read_one( accdb, fork_id, fd_sysvar_clock_id.uc );
69 4533 : if( FD_UNLIKELY( !acc.lamports || acc.data_len<sizeof(fd_sol_sysvar_clock_t) ) ) {
70 : /* This check is needed as a quirk of the fuzzer. If a sysvar
71 : account exists in the accounts database, but doesn't have any
72 : lamports, this means that the account does not exist. This
73 : wouldn't happen in a real execution environment. */
74 0 : fd_accdb_unread_one( accdb, &acc );
75 0 : return NULL;
76 0 : }
77 :
78 4533 : fd_memcpy( clock, acc.data, sizeof(fd_sol_sysvar_clock_t) );
79 4533 : fd_accdb_unread_one( accdb, &acc );
80 4533 : return clock;
81 4533 : }
82 :
83 : void
84 : fd_sysvar_clock_init( fd_bank_t * bank,
85 : fd_accdb_t * accdb,
86 6 : fd_capture_ctx_t * capture_ctx ) {
87 6 : long timestamp = unix_timestamp_from_genesis( bank );
88 :
89 6 : fd_sol_sysvar_clock_t clock = {
90 6 : .slot = bank->f.slot,
91 6 : .epoch = 0,
92 6 : .epoch_start_timestamp = timestamp,
93 6 : .leader_schedule_epoch = 1,
94 6 : .unix_timestamp = timestamp,
95 6 : };
96 6 : fd_sysvar_clock_write( bank, accdb, capture_ctx, &clock );
97 6 : }
98 :
99 : #define SORT_NAME sort_stake_ts
100 552 : #define SORT_KEY_T ts_est_ele_t
101 276 : #define SORT_BEFORE(a,b) ( (a).timestamp < (b).timestamp )
102 : #include "../../../util/tmpl/fd_sort.c"
103 :
104 : static void
105 : accum_vote_stakes( fd_bank_t * bank,
106 : fd_runtime_stack_t * runtime_stack,
107 : uint128 * total_stake_out,
108 4512 : ulong * ts_ele_cnt_out ) {
109 :
110 4512 : ts_est_ele_t * ts_eles = runtime_stack->clock_ts.staked_ts;
111 4512 : ulong ts_ele_cnt = 0UL;
112 :
113 4512 : uint128 total_stake = 0UL;
114 :
115 4512 : fd_epoch_schedule_t const * epoch_schedule = &bank->f.epoch_schedule;
116 4512 : ulong current_slot = bank->f.slot;
117 :
118 4512 : fd_vote_stakes_t * vote_stakes = fd_bank_vote_stakes( bank );
119 4512 : ulong fork_id = bank->vote_stakes_fork_id;
120 :
121 4512 : uchar __attribute__((aligned(FD_VOTE_STAKES_ITER_ALIGN))) iter_mem[ FD_VOTE_STAKES_ITER_FOOTPRINT ];
122 4512 : for( fd_vote_stakes_iter_t * iter = fd_vote_stakes_iter_init( vote_stakes, fork_id, FD_VOTE_STAKES_ITER_T_2, iter_mem );
123 9669 : !fd_vote_stakes_iter_done( vote_stakes, fork_id, FD_VOTE_STAKES_ITER_T_2, iter );
124 5157 : fd_vote_stakes_iter_next( vote_stakes, fork_id, FD_VOTE_STAKES_ITER_T_2, iter ) ) {
125 5157 : fd_pubkey_t pubkey;
126 5157 : ulong stake_t_2;
127 5157 : ulong last_vote_slot;
128 5157 : long last_vote_timestamp;
129 5157 : uchar is_valid;
130 5157 : fd_vote_stakes_iter_ele( vote_stakes, fork_id, FD_VOTE_STAKES_ITER_T_2, iter, &pubkey, NULL, &stake_t_2,
131 5157 : &last_vote_slot, &last_vote_timestamp, NULL, &is_valid, NULL, NULL, NULL );
132 5157 : if( FD_UNLIKELY( !is_valid ) ) continue;
133 :
134 : /* https://github.com/anza-xyz/agave/blob/v3.0.0/runtime/src/bank.rs#L2445 */
135 4971 : if( FD_UNLIKELY( current_slot<last_vote_slot ) ) {
136 : /* Don't count vote accounts with a last vote slot that is greater
137 : than the current slot. */
138 0 : continue;
139 0 : }
140 4971 : ulong slot_delta = current_slot-last_vote_slot;
141 :
142 : /* Don't count vote accounts that haven't voted in the past 432k
143 : slots (length of an epoch).
144 : https://github.com/anza-xyz/agave/blob/v3.0.0/runtime/src/bank.rs#L2446-L2447 */
145 4971 : if( FD_UNLIKELY( slot_delta>epoch_schedule->slots_per_epoch ) ) {
146 618 : continue;
147 618 : }
148 :
149 : /* Calculate the timestamp estimate by taking the last vote
150 : timestamp and adding the estimated time since the last vote
151 : (delta from last vote slot to current slot * slot duration).
152 : https://github.com/anza-xyz/agave/blob/v2.3.7/runtime/src/stake_weighted_timestamp.rs#L44-L45 */
153 4353 : ulong offset = fd_slot_params_slot_range_duration_ns( bank, last_vote_slot+1UL, current_slot+1UL );
154 4353 : long estimate = fd_long_sat_add( last_vote_timestamp, (long)(offset / NS_IN_S) );
155 :
156 : /* For each timestamp, accumulate the stake from E-2. If the entry
157 : for the timestamp doesn't exist yet, insert it. Otherwise,
158 : update the existing entry.
159 : https://github.com/anza-xyz/agave/blob/v2.3.7/runtime/src/stake_weighted_timestamp.rs#L46-L53 */
160 4353 : ts_eles[ ts_ele_cnt ] = (ts_est_ele_t){
161 4353 : .timestamp = estimate,
162 4353 : .stake = { .ud=stake_t_2 },
163 4353 : };
164 4353 : ts_ele_cnt++;
165 :
166 : /* https://github.com/anza-xyz/agave/blob/v2.3.7/runtime/src/stake_weighted_timestamp.rs#L54 */
167 4353 : total_stake += stake_t_2;
168 4353 : }
169 :
170 4512 : *total_stake_out = total_stake;
171 4512 : *ts_ele_cnt_out = ts_ele_cnt;
172 4512 : }
173 :
174 : /* get_timestamp_estimate calculates a timestamp estimate. Does not
175 : modify the slot context. Walks all cached vote accounts (from the
176 : "bank") and calculates a unix timestamp estimate. Returns the
177 : timestamp estimate. Crashes the process with FD_LOG_ERR on failure
178 : (e.g. too many vote accounts).
179 :
180 : https://github.com/anza-xyz/agave/blob/v2.3.7/runtime/src/bank.rs#L2563-L2601 */
181 : static long
182 : get_timestamp_estimate( fd_bank_t * bank,
183 : fd_sol_sysvar_clock_t * clock,
184 : fd_runtime_stack_t * runtime_stack,
185 : ulong const * parent_epoch,
186 4512 : int * out_estimate_present ) {
187 4512 : fd_epoch_schedule_t const * epoch_schedule = &bank->f.epoch_schedule;
188 4512 : ulong current_slot = bank->f.slot;
189 :
190 4512 : ts_est_ele_t * ts_eles = runtime_stack->clock_ts.staked_ts;
191 :
192 : /* https://github.com/anza-xyz/agave/blob/v2.3.7/runtime/src/stake_weighted_timestamp.rs#L41 */
193 4512 : ulong ts_ele_cnt = 0UL;
194 4512 : uint128 total_stake = 0UL;
195 :
196 : /* A timestamp estimate is calculated at every slot using the most
197 : recent vote states of voting validators. This estimated is based on
198 : a stake weighted median using the stake as of the end of epoch E-2
199 : if we are currently in epoch E. We do not count vote accounts that
200 : have not voted in an epoch's worth of slots (432k). */
201 :
202 4512 : ulong curr_epoch = fd_slot_to_epoch( epoch_schedule, bank->f.slot, NULL );
203 :
204 4512 : accum_vote_stakes( bank, runtime_stack, &total_stake, &ts_ele_cnt );
205 :
206 : /* https://github.com/anza-xyz/agave/blob/v2.3.7/runtime/src/stake_weighted_timestamp.rs#L56-L58 */
207 4512 : if( FD_UNLIKELY( total_stake==0UL ) ) {
208 435 : *out_estimate_present = 0;
209 435 : return 0L;
210 435 : }
211 :
212 4077 : sort_stake_ts_inplace( ts_eles, ts_ele_cnt );
213 :
214 : /* Populate estimate with the stake-weighted median timestamp.
215 : https://github.com/anza-xyz/agave/blob/v2.3.7/runtime/src/stake_weighted_timestamp.rs#L59-L68 */
216 4077 : uint128 stake_accumulator = 0;
217 4077 : long estimate = 0L;
218 4353 : for( ulong i=0UL; i<ts_ele_cnt; i++ ) {
219 4353 : stake_accumulator = fd_uint128_sat_add( stake_accumulator, ts_eles[i].stake.ud );
220 4353 : if( stake_accumulator>(total_stake/2UL) ) {
221 4077 : estimate = ts_eles[ i ].timestamp;
222 4077 : break;
223 4077 : }
224 4353 : }
225 :
226 : /* Bound estimate by `max_allowable_drift` since the start of the
227 : epoch.
228 : https://github.com/anza-xyz/agave/blob/v2.3.7/runtime/src/stake_weighted_timestamp.rs#L69-L99 */
229 4077 : ulong epoch_for_start_slot = parent_epoch ? *parent_epoch : curr_epoch;
230 4077 : ulong epoch_start_slot = fd_epoch_slot0( epoch_schedule, epoch_for_start_slot );
231 4077 : long epoch_start_timestamp = clock->epoch_start_timestamp;
232 :
233 : /* https://github.com/anza-xyz/agave/blob/v2.3.7/runtime/src/stake_weighted_timestamp.rs#L71-L72 */
234 4077 : ulong poh_estimate_offset = fd_slot_params_slot_range_duration_ns( bank, epoch_start_slot+1UL, current_slot+1UL );
235 :
236 : /* https://github.com/anza-xyz/agave/blob/v2.3.7/runtime/src/stake_weighted_timestamp.rs#L73-L77 */
237 4077 : ulong estimate_offset = fd_ulong_sat_mul( NS_IN_S, fd_ulong_sat_sub( (ulong)estimate, (ulong)epoch_start_timestamp ) );
238 :
239 : /* https://github.com/anza-xyz/agave/blob/v2.3.7/runtime/src/stake_weighted_timestamp.rs#L78-L81 */
240 4077 : ulong max_allowable_drift_fast = fd_ulong_sat_mul( poh_estimate_offset, MAX_ALLOWABLE_DRIFT_FAST_PERCENT ) / 100UL;
241 4077 : ulong max_allowable_drift_slow = fd_ulong_sat_mul( poh_estimate_offset, MAX_ALLOWABLE_DRIFT_SLOW_PERCENT ) / 100UL;
242 :
243 : /* https://github.com/anza-xyz/agave/blob/v2.3.7/runtime/src/stake_weighted_timestamp.rs#L82-L98 */
244 4077 : if( estimate_offset>poh_estimate_offset && fd_ulong_sat_sub( estimate_offset, poh_estimate_offset )>max_allowable_drift_slow ) {
245 72 : estimate = fd_long_sat_add(
246 72 : epoch_start_timestamp,
247 72 : fd_long_sat_add( (long)poh_estimate_offset / NS_IN_S, (long)max_allowable_drift_slow / NS_IN_S ) );
248 4005 : } else if( estimate_offset<poh_estimate_offset && fd_ulong_sat_sub( poh_estimate_offset, estimate_offset )>max_allowable_drift_fast ) {
249 3561 : estimate = fd_long_sat_sub(
250 3561 : fd_long_sat_add( epoch_start_timestamp, (long)poh_estimate_offset / NS_IN_S ),
251 3561 : (long)max_allowable_drift_fast / NS_IN_S );
252 3561 : }
253 :
254 4077 : *out_estimate_present = 1;
255 4077 : return estimate;
256 4512 : }
257 :
258 : /* TODO: This function should be called from genesis bootup as well with
259 : parent_epoch = NULL
260 : https://github.com/anza-xyz/agave/blob/v2.3.7/runtime/src/bank.rs#L2158-L2215 */
261 : void
262 : fd_sysvar_clock_update( fd_bank_t * bank,
263 : fd_accdb_t * accdb,
264 : fd_capture_ctx_t * capture_ctx,
265 : fd_runtime_stack_t * runtime_stack,
266 4512 : ulong const * parent_epoch ) {
267 4512 : fd_sol_sysvar_clock_t clock_[1];
268 4512 : fd_sol_sysvar_clock_t * clock = fd_sysvar_clock_read( accdb, bank->accdb_fork_id, clock_ );
269 4512 : if( FD_UNLIKELY( !clock ) ) FD_LOG_ERR(( "fd_sysvar_clock_read failed" ));
270 :
271 4512 : fd_epoch_schedule_t const * epoch_schedule = &bank->f.epoch_schedule;
272 4512 : ulong current_slot = bank->f.slot;
273 4512 : ulong current_epoch = fd_slot_to_epoch( epoch_schedule, current_slot, NULL );
274 :
275 : /* https://github.com/anza-xyz/agave/blob/v2.3.7/runtime/src/bank.rs#L2159 */
276 4512 : long unix_timestamp = clock->unix_timestamp;
277 :
278 : /* https://github.com/anza-xyz/agave/blob/v2.3.7/runtime/src/bank.rs#L2175 */
279 4512 : long ancestor_timestamp = clock->unix_timestamp;
280 :
281 : /* TODO: Are we handling slot 0 correctly?
282 : https://github.com/anza-xyz/agave/blob/v2.3.7/runtime/src/bank.rs#L2176-L2183 */
283 4512 : int estimate_present = 0;
284 4512 : long timestamp_estimate = get_timestamp_estimate( bank, clock, runtime_stack, parent_epoch, &estimate_present );
285 :
286 : /* If the timestamp was successfully calculated, use it. Otherwise,
287 : keep the old one. */
288 4512 : if( FD_LIKELY( estimate_present ) ) {
289 4077 : unix_timestamp = timestamp_estimate;
290 :
291 : /* https://github.com/anza-xyz/agave/blob/v2.3.7/runtime/src/bank.rs#L2180-L2182 */
292 4077 : if( timestamp_estimate<ancestor_timestamp ) {
293 3 : unix_timestamp = ancestor_timestamp;
294 3 : }
295 4077 : }
296 :
297 : /* https://github.com/anza-xyz/agave/blob/v2.3.7/runtime/src/bank.rs#L2191-L2197 */
298 4512 : long epoch_start_timestamp = (parent_epoch!=NULL && *parent_epoch!=current_epoch) ?
299 282 : unix_timestamp :
300 4512 : clock->epoch_start_timestamp;
301 :
302 : /* https://github.com/anza-xyz/agave/blob/v2.3.7/runtime/src/bank.rs#L2198-L2201 */
303 4512 : if( FD_UNLIKELY( current_slot==0UL ) ) {
304 0 : long timestamp_from_genesis = unix_timestamp_from_genesis( bank );
305 0 : unix_timestamp = timestamp_from_genesis;
306 0 : epoch_start_timestamp = timestamp_from_genesis;
307 0 : }
308 :
309 : /* https://github.com/anza-xyz/agave/blob/v2.3.7/runtime/src/bank.rs#L2202-L2208 */
310 4512 : *clock = (fd_sol_sysvar_clock_t){
311 4512 : .slot = current_slot,
312 4512 : .epoch_start_timestamp = epoch_start_timestamp,
313 4512 : .epoch = current_epoch,
314 4512 : .leader_schedule_epoch = fd_slot_to_leader_schedule_epoch( epoch_schedule, current_slot ),
315 4512 : .unix_timestamp = unix_timestamp,
316 4512 : };
317 :
318 : /* https://github.com/anza-xyz/agave/blob/v2.3.7/runtime/src/bank.rs#L2209-L2214 */
319 4512 : fd_sysvar_clock_write( bank, accdb, capture_ctx, clock );
320 4512 : }
321 :
322 : void
323 : fd_sysvar_clock_update_slot_alpenglow( fd_bank_t * bank,
324 : fd_accdb_t * accdb,
325 6 : fd_capture_ctx_t * capture_ctx ) {
326 6 : fd_sol_sysvar_clock_t clock_[1];
327 6 : fd_sol_sysvar_clock_t * clock = fd_sysvar_clock_read( accdb, bank->accdb_fork_id, clock_ );
328 6 : if( FD_UNLIKELY( !clock ) ) FD_LOG_ERR(( "fd_sysvar_clock_read failed" ));
329 :
330 6 : fd_epoch_schedule_t const * epoch_schedule = &bank->f.epoch_schedule;
331 6 : ulong current_epoch = fd_slot_to_epoch( epoch_schedule, bank->f.slot, NULL );
332 6 : ulong parent_epoch = fd_slot_to_epoch( epoch_schedule, bank->f.parent_slot, NULL );
333 :
334 6 : long epoch_start_timestamp;
335 6 : if( FD_UNLIKELY( !bank->f.slot ) ) epoch_start_timestamp = unix_timestamp_from_genesis( bank );
336 6 : else if( FD_UNLIKELY( parent_epoch!=current_epoch ) ) epoch_start_timestamp = clock->unix_timestamp;
337 6 : else epoch_start_timestamp = clock->epoch_start_timestamp;
338 :
339 6 : *clock = (fd_sol_sysvar_clock_t){
340 6 : .slot = bank->f.slot,
341 6 : .epoch_start_timestamp = epoch_start_timestamp,
342 6 : .epoch = current_epoch,
343 6 : .leader_schedule_epoch = fd_slot_to_leader_schedule_epoch( epoch_schedule, bank->f.slot ),
344 6 : .unix_timestamp = clock->unix_timestamp, /* parent's footer timestamp */
345 6 : };
346 6 : fd_sysvar_clock_write( bank, accdb, capture_ctx, clock );
347 6 : }
|
