diff options
| author | Ivan Shapovalov <intelfx@intelfx.name> | 2023-12-22 09:51:17 +0300 |
|---|---|---|
| committer | Ivan Shapovalov <intelfx@intelfx.name> | 2023-12-22 11:41:54 +0300 |
| commit | ae818d9579bc521f2281237986ceb4fdb8827ede (patch) | |
| tree | eb5b38ac0ab81abad88f3ef7d5a73bc8a7dfb825 | |
| parent | eaca023d5379bcf8f31a7a83ded985fe1565fc58 (diff) | |
Makefile: avoid recursively expanding expensive variables
Specifically, do not recursively expand $(CFLAGS) because this leads to
repeatedly performing compile tests (e. g. cc-disable-warning) on every
recipe execution.
Without (nproc=32):
```
$ time env -i PATH=/usr/bin BCACHEFS_FUSE=1 NO_RUST=1 make -j$(nproc)
<...>
[LD] bcachefs
72,48s user 11,29s system 190% cpu 44,036 total
```
With:
```
$ time env -i PATH=/usr/bin BCACHEFS_FUSE=1 NO_RUST=1 make -j$(nproc)
<...>
[LD] bcachefs
66,79s user 5,17s system 1955% cpu 3,679 total
```
| -rw-r--r-- | Makefile | 15 |
1 files changed, 11 insertions, 4 deletions
@@ -21,6 +21,10 @@ else CARGO_CLEAN_ARGS = --quiet endif +# Prevent recursive expansions of $(CFLAGS) to avoid repeatedly performing +# compile tests +CFLAGS:=$(CFLAGS) + CFLAGS+=-std=gnu11 -O2 -g -MMD -Wall -fPIC \ -Wno-pointer-sign \ -Wno-deprecated-declarations \ @@ -38,6 +42,9 @@ CFLAGS+=-std=gnu11 -O2 -g -MMD -Wall -fPIC \ -DNO_BCACHEFS_SYSFS \ -DVERSION_STRING='"$(VERSION)"' \ $(EXTRA_CFLAGS) + +# Intenionally not doing the above to $(LDFLAGS) because we rely on +# recursive expansion here (CFLAGS is not yet completely built by this line) LDFLAGS+=$(CFLAGS) $(EXTRA_LDFLAGS) ifdef CARGO_TOOLCHAIN_VERSION @@ -154,11 +161,11 @@ TAGS: tags: ctags -R . -SRCS=$(sort $(shell find . -type f ! -path '*/.*/*' -iname '*.c')) -DEPS=$(SRCS:.c=.d) +SRCS:=$(sort $(shell find . -type f ! -path '*/.*/*' -iname '*.c')) +DEPS:=$(SRCS:.c=.d) -include $(DEPS) -OBJS=$(SRCS:.c=.o) +OBJS:=$(SRCS:.c=.o) %.o: %.c @echo " [CC] $@" @@ -180,7 +187,7 @@ libbcachefs.a: $(filter-out ./tests/%.o, $(OBJS)) @echo " [AR] $@" $(Q)ar -rc $@ $+ -RUST_SRCS=$(shell find rust-src/src rust-src/bch_bindgen/src -type f -iname '*.rs') +RUST_SRCS:=$(shell find rust-src/src rust-src/bch_bindgen/src -type f -iname '*.rs') rust-src/target/release/libbcachefs_rust.a: $(RUST_SRCS) $(CARGO_BUILD) |