hlint-bench: pass --max-jobs, --cores more places

nix.mk should not be touched even if it looks like an issue.

Makefile

@@ -1,11 +1,18 @@
 help: ## Print documentation
 	@{ grep -hE '^[a-zA-Z0-9_-]+:.*?## .*$$' $(MAKEFILE_LIST); echo -e '$(EXTRA_HELP)'; } | sed 's/^ //' | sort | awk 'BEGIN {FS = ":.*?## "}; {printf "\033[36m%-33s\033[0m %s\n", $$1, $$2}'
 
+NUM_PROC:=$(shell nproc --all)
+MFLAGS_STRIP:=$(strip $(MAKEFLAGS))
+MFLAGS_FIRST:=$(firstword $(filter --j%,-$(MFLAGS_STRIP)))
+ifneq (,$(MFLAGS_FIRST))
+	JOBS:=$(subst --j,,$(MFLAGS_FIRST))
+	JOBS:=$(intcmp $(JOBS),$(NUM_PROC),$(NUM_PROC),$(NUM_PROC),$(JOBS))
+endif
+
 include lib.mk
 include nix.mk
 
 PROJECT_NAME = cardano-node
-NUM_PROC     = $(shell nproc --all)
 
 ## One of: coay shey alra mary alzo bage
 ERA     ?= coay
@@ -18,25 +25,26 @@ BATCH   ?=
 ARGS    ?=
 CMD     ?=
 RUN     ?=
+JOBS    ?=: $(shell expr $(NUM_PROC) \* 5)
 
 lint hlint: ## Run the CI version of hlint
-	nix build --no-link '.#checks/hlint' --cores 0
+	nix build --no-link '.#checks/hlint' --max-jobs $(JOBS) --cores 0
 haddock-hoogle haddocks hoogle:
-	if test -z "$$IN_NIX_SHELL"; then nix-shell --run 'cabal update && cabal haddock all --haddock-hoogle'; else cabal update && cabal haddock all --haddock-hoogle; fi
+	if test -z "$$IN_NIX_SHELL"; then nix-shell --max-jobs $(JOBS) --cores 0 --run "cabal update && cabal --jobs=$$JOBS haddock all --haddock-hoogle"; else cabal update && cabal --jobs=$(JOBS) haddock all --haddock-hoogle; fi
 host-hlint: ## Run the system (not Nix) version of hlint
 	hlint bench cardano-{api,cli,node,node-capi,node-chairman,submit-api,testnet,tracer}
 
 stylish-haskell: ## Apply stylish-haskell on all *.hs files
 	@find . -type f -name "*.hs" -not -path '.git' -print0 | xargs -0 stylish-haskell -i
 
 cabal-hashes:
-	nix run .#checkCabalProject
+	nix run --max-jobs $(JOBS) --cores 0 .#checkCabalProject
 
 cli node:
-	cabal --ghc-options="+RTS -qn8 -A32M -RTS" build cardano-$@
+	cabal --jobs=$(JOBS) --ghc-options="+RTS -qn8 -A32M -RTS" build cardano-$@
 
 trace-documentation:
-	cabal run -- exe:cardano-node trace-documentation --config 'configuration/cardano/mainnet-config-new-tracing.yaml' --output-file 'doc/new-tracing/tracers_doc_generated.md'
+	cabal --jobs=$(JOBS) run -- exe:cardano-node trace-documentation --config 'configuration/cardano/mainnet-config-new-tracing.yaml' --output-file 'doc/new-tracing/tracers_doc_generated.md'
 
 ###
 ### Workbench
@@ -55,7 +63,7 @@ workbench-internals-walkthrough:
 ## Base targets:
 ##
 shell:                                           ## Nix shell, (workbench from /nix/store), vars: PROFILE, CMD, RUN
-	nix-shell -A 'workbench-shell' --max-jobs 8 --cores 0 --show-trace --argstr profileName ${PROFILE} --argstr backendName ${BACKEND} ${ARGS} ${if ${CMD},--command "${CMD}"} ${if ${RUN},--run "${RUN}"}
+	nix-shell -A 'workbench-shell' --max-jobs $(JOBS) --cores 0 --show-trace --argstr profileName ${PROFILE} --argstr backendName ${BACKEND} ${ARGS} ${if ${CMD},--command "${CMD}"} ${if ${RUN},--run "${RUN}"}
 shell-dev shell-prof shell-nix: shell
 shell-nix: ARGS += --arg 'useCabalRun' false ## Nix shell, (workbench from Nix store), vars: PROFILE, CMD, RUN
 shell-prof: ARGS += --arg 'profiling' '"space"'  ## Nix shell, everything Haskell built profiled
@@ -64,12 +72,12 @@ analyse: RUN := wb analyse std ${TAG}
 analyse: shell
 
 list-profiles:                                   ## List workbench profiles
-	nix build .#all-profiles-json && cat result
+	nix build --max-jobs $(JOBS) --cores 0 .#all-profiles-json && cat result
 show-profile:                                    ## NAME=profile-name
 	@test -n "${NAME}" || { echo 'HELP:  to specify profile to show, add NAME=profle-name' && exit 1; }
-	nix build .#all-profiles-json --json --option substitute false | jq '.[0].outputs.out' -r | xargs jq ".\"${NAME}\" | if . == null then error(\"\n###\n### Error:  unknown profile: ${NAME}  Please consult:  make list-profiles\n###\") else . end"
+	nix build --max-jobs $(JOBS) --cores 0 .#all-profiles-json --json --option substitute false | jq '.[0].outputs.out' -r | xargs jq ".\"${NAME}\" | if . == null then error(\"\n###\n### Error:  unknown profile: ${NAME}  Please consult:  make list-profiles\n###\") else . end"
 ps:                                              ## Plain-text list of profiles
-	@nix build .#workbench.profile-names-json --json | jq '.[0].outputs.out' -r | xargs jq '.[]' --raw-output
+	@nix build --max-jobs $(JOBS) --cores 0 .#workbench.profile-names-json --json | jq '.[0].outputs.out' -r | xargs jq '.[]' --raw-output
 
 ##
 ## Profile-based cluster shells (autogenerated targets)