d118b08f7e
glibc's opendir allocates a minimum of 32kb, when called recursively for a directory tree the memory consumption can add up - nearly 300kb during perf start-up when processing modules. Add a stack allocated variant of readdir sized a little more than 1kb. As getdents64 may be missing from libc, add support using syscall. As the system call number maybe missing, add #defines for those. Note, an earlier version of this patch had a feature test for getdents64 but there were problems on certains distros where getdents64 would be #define renamed to getdents breaking the code. The syscall use was made uncondtional to work around this. There is context in: https://lore.kernel.org/lkml/20231207050433.1426834-1-irogers@google.com/ Signed-off-by: Ian Rogers <irogers@google.com> Link: https://lore.kernel.org/r/20250222061015.303622-2-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
3.1 KiB
SPDX-License-Identifier: GPL-2.0
include ../../scripts/Makefile.include include ../../scripts/utilities.mak # QUIET_CLEAN
ifeq ($(srctree),) srctree := $(patsubst %/,%,$(dir $(CURDIR))) srctree := $(patsubst %/,%,$(dir $(srctree))) srctree := $(patsubst %/,%,$(dir $(srctree))) #$(info Determined 'srctree' to be $(srctree)) endif
CC ?= $(CROSS_COMPILE)gcc AR ?= $(CROSS_COMPILE)ar LD ?= $(CROSS_COMPILE)ld
MAKEFLAGS += --no-print-directory
INSTALL = install
Use DESTDIR for installing into a different root directory.
This is useful for building a package. The program will be
installed in this directory as if it was the root directory.
Then the build tool can move it later.
DESTDIR ?= DESTDIR_SQ = '$(subst ',''',$(DESTDIR))'
LIBFILE = $(OUTPUT)libapi.a
CFLAGS := $(EXTRA_WARNINGS) $(EXTRA_CFLAGS) CFLAGS += -ggdb3 -Wall -Wextra -std=gnu99 -U_FORTIFY_SOURCE -fPIC
ifeq ($(DEBUG),0) CFLAGS += -O3 endif
ifeq ($(DEBUG),0) CFLAGS += -D_FORTIFY_SOURCE endif
Treat warnings as errors unless directed not to
ifneq ($(WERROR),0) CFLAGS += -Werror endif
CFLAGS += -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 CFLAGS += -I$(srctree)/tools/lib/api CFLAGS += -I$(srctree)/tools/include
RM = rm -f
API_IN := $(OUTPUT)libapi-in.o
ifeq ($(LP64), 1) libdir_relative = lib64 else libdir_relative = lib endif
prefix ?= libdir = $(prefix)/$(libdir_relative)
Shell quotes
libdir_SQ = $(subst ',''',$(libdir))
all:
export srctree OUTPUT CC LD CFLAGS V include $(srctree)/tools/build/Makefile.include include $(srctree)/tools/scripts/Makefile.include
all: fixdep $(LIBFILE)
$(API_IN): FORCE @$(MAKE) $(build)=libapi
$(LIBFILE): $(API_IN) $(QUIET_AR)$(RM) $@ && $(AR) rcs $@ $(API_IN)
define do_install_mkdir
if [ ! -d '$(DESTDIR_SQ)$1' ]; then
$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$1';
fi
endef
define do_install
if [ ! -d '$2' ]; then
$(INSTALL) -d -m 755 '$2';
fi;
$(INSTALL) $1 $(if $3,-m $3,) '$2'
endef
install_lib: $(LIBFILE)
$(call QUIET_INSTALL, $(LIBFILE))
$(call do_install_mkdir,$(libdir_SQ));
cp -fpR $(LIBFILE) $(DESTDIR)$(libdir_SQ)
HDRS := cpu.h debug.h io.h io_dir.h FD_HDRS := fd/array.h FS_HDRS := fs/fs.h fs/tracing_path.h INSTALL_HDRS_PFX := $(DESTDIR)$(prefix)/include/api INSTALL_HDRS := $(addprefix $(INSTALL_HDRS_PFX)/, $(HDRS)) INSTALL_FD_HDRS := $(addprefix $(INSTALL_HDRS_PFX)/, $(FD_HDRS)) INSTALL_FS_HDRS := $(addprefix $(INSTALL_HDRS_PFX)/, $(FS_HDRS))
$(INSTALL_HDRS): $(INSTALL_HDRS_PFX)/%.h: %.h
$(call QUIET_INSTALL, $@)
$(call do_install,$<,$(INSTALL_HDRS_PFX)/,644)
$(INSTALL_FD_HDRS): $(INSTALL_HDRS_PFX)/fd/%.h: fd/%.h
$(call QUIET_INSTALL, $@)
$(call do_install,$<,$(INSTALL_HDRS_PFX)/fd/,644)
$(INSTALL_FS_HDRS): $(INSTALL_HDRS_PFX)/fs/%.h: fs/%.h
$(call QUIET_INSTALL, $@)
$(call do_install,$<,$(INSTALL_HDRS_PFX)/fs/,644)
install_headers: $(INSTALL_HDRS) $(INSTALL_FD_HDRS) $(INSTALL_FS_HDRS) $(call QUIET_INSTALL, libapi_headers)
install: install_lib install_headers
clean:
$(call QUIET_CLEAN, libapi) $(RM) $(LIBFILE);
find $(or $(OUTPUT),.) -name *.o -or -name *.o.cmd -or -name *.o.d | xargs $(RM)
FORCE:
.PHONY: clean FORCE