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(I'm so sorry!) Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158// SPDX-License-Identifier: GPL-2.0+(* * Copyright (C) 2016 Luc Maranget <luc.maranget@inria.fr> for Inria * Copyright (C) 2017 Alan Stern <stern@rowland.harvard.edu> *)
(* * Generate coherence orders and handle lock operations *)
include "cross.cat"
(* * The lock-related events generated by herd7 are as follows: * * LKR Lock-Read: the read part of a spin_lock() or successful * spin_trylock() read-modify-write event pair * LKW Lock-Write: the write part of a spin_lock() or successful * spin_trylock() RMW event pair * UL Unlock: a spin_unlock() event * LF Lock-Fail: a failed spin_trylock() event * RL Read-Locked: a spin_is_locked() event which returns True * RU Read-Unlocked: a spin_is_locked() event which returns False * * LKR and LKW events always come paired, like all RMW event sequences. * * LKR, LF, RL, and RU are read events; LKR has Acquire ordering. * LKW and UL are write events; UL has Release ordering. * LKW, LF, RL, and RU have no ordering properties. *)
(* Backward compatibility *)let RL = try RL with emptysetlet RU = try RU with emptyset
(* Treat RL as a kind of LF: a read with no ordering properties *)let LF = LF | RL
(* There should be no ordinary R or W accesses to spinlocks or SRCU structs *)let ALL-LOCKS = LKR | LKW | UL | LF | RU | Srcu-lock | Srcu-unlock | Sync-srcuflag ~empty [M \ IW \ ALL-LOCKS] ; loc ; [ALL-LOCKS] as mixed-lock-accesses
(* Link Lock-Reads to their RMW-partner Lock-Writes *)let lk-rmw = ([LKR] ; po-loc ; [LKW]) \ (po ; po)let rmw = rmw | lk-rmw
(* The litmus test is invalid if an LKR/LKW event is not part of an RMW pair *)flag ~empty LKW \ range(lk-rmw) as unpaired-LKWflag ~empty LKR \ domain(lk-rmw) as unpaired-LKR
(* * An LKR must always see an unlocked value; spin_lock() calls nested * inside a critical section (for the same lock) always deadlock. *)empty ([LKW] ; po-loc ; [LKR]) \ (po-loc ; [UL] ; po-loc) as lock-nest
(* * In the same way, spin_is_locked() inside a critical section must always * return True (no RU events can be in a critical section for the same lock). *)empty ([LKW] ; po-loc ; [RU]) \ (po-loc ; [UL] ; po-loc) as nested-is-locked
(* The final value of a spinlock should not be tested *)flag ~empty [FW] ; loc ; [ALL-LOCKS] as lock-final
(* * Put lock operations in their appropriate classes, but leave UL out of W * until after the co relation has been generated. *)let R = R | LKR | LF | RUlet W = W | LKW
let Release = Release | ULlet Acquire = Acquire | LKR
(* Match LKW events to their corresponding UL events *)let critical = ([LKW] ; po-loc ; [UL]) \ (po-loc ; [LKW | UL] ; po-loc)
flag ~empty UL \ range(critical) as unmatched-unlock
(* Allow up to one unmatched LKW per location; more must deadlock *)let UNMATCHED-LKW = LKW \ domain(critical)empty ([UNMATCHED-LKW] ; loc ; [UNMATCHED-LKW]) \ id as unmatched-locks
(* rfi for LF events: link each LKW to the LF events in its critical section *)let rfi-lf = ([LKW] ; po-loc ; [LF]) \ ([LKW] ; po-loc ; [UL] ; po-loc)
(* Utility macro to convert a single pair to a single-edge relation *)let pair-to-relation p = p ++ 0
(* * If a given LF event e is outside a critical section, it cannot read * internally but it may read from an LKW event in another thread. * Compute the relation containing these possible edges. *)let possible-rfe-noncrit-lf e = (LKW * {e}) & loc & ext
(* Compute set of sets of possible rfe edges for LF events *)let all-possible-rfe-lf = (* * Convert the possible-rfe-noncrit-lf relation for e * to a set of single edges *) let set-of-singleton-rfe-lf e = map pair-to-relation (possible-rfe-noncrit-lf e) (* Do this for each LF event e that isn't in rfi-lf *) in map set-of-singleton-rfe-lf (LF \ range(rfi-lf))
(* Generate all rf relations for LF events *)with rfe-lf from cross(all-possible-rfe-lf)let rf-lf = rfe-lf | rfi-lf
(* * A given RU event e may read internally from the last po-previous UL, * or it may read from a UL event in another thread or the initial write. * Compute the relation containing these possible edges. *)let possible-rf-ru e = (((UL * {e}) & po-loc) \ ([UL] ; po-loc ; [UL] ; po-loc)) | (((UL | IW) * {e}) & loc & ext)
(* Compute set of sets of possible rf edges for RU events *)let all-possible-rf-ru = (* Convert the possible-rf-ru relation for e to a set of single edges *) let set-of-singleton-rf-ru e = map pair-to-relation (possible-rf-ru e) (* Do this for each RU event e *) in map set-of-singleton-rf-ru RU
(* Generate all rf relations for RU events *)with rf-ru from cross(all-possible-rf-ru)
(* Final rf relation *)let rf = rf | rf-lf | rf-ru
(* Generate all co relations, including LKW events but not UL *)let co0 = co0 | ([IW] ; loc ; [LKW]) | (([LKW] ; loc ; [UNMATCHED-LKW]) \ [UNMATCHED-LKW])include "cos-opt.cat"let W = W | ULlet M = R | W
(* Merge UL events into co *)let co = (co | critical | (critical^-1 ; co))+let coe = co & extlet coi = co & int
(* Merge LKR events into rf *)let rf = rf | ([IW | UL] ; singlestep(co) ; lk-rmw^-1)let rfe = rf & extlet rfi = rf & int
let fr = rf^-1 ; colet fre = fr & extlet fri = fr & int
show co,rf,fr