https://github.com/torvalds/linux
Revision 8fcb2312d1e3300e81aa871aad00d4c038cfc184 authored by Olof Johansson on 16 November 2018, 23:08:00 UTC, committed by Linus Torvalds on 18 November 2018, 18:15:09 UTC
The existing code triggered an invalid warning about 'rq' possibly being
used uninitialized.  Instead of doing the silly warning suppression by
initializa it to NULL, refactor the code to bail out early instead.

Warning was:

  kernel/sched/psi.c: In function `cgroup_move_task':
  kernel/sched/psi.c:639:13: warning: `rq' may be used uninitialized in this function [-Wmaybe-uninitialized]

Link: http://lkml.kernel.org/r/20181103183339.8669-1-olof@lixom.net
Fixes: 2ce7135adc9ad ("psi: cgroup support")
Signed-off-by: Olof Johansson <olof@lixom.net>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent ca0246b
Raw File
Tip revision: 8fcb2312d1e3300e81aa871aad00d4c038cfc184 authored by Olof Johansson on 16 November 2018, 23:08:00 UTC
kernel/sched/psi.c: simplify cgroup_move_task()
Tip revision: 8fcb231
Kbuild
# SPDX-License-Identifier: GPL-2.0
#
# Kbuild for top-level directory of the kernel
# This file takes care of the following:
# 1) Generate bounds.h
# 2) Generate timeconst.h
# 3) Generate asm-offsets.h (may need bounds.h and timeconst.h)
# 4) Check for missing system calls
# 5) Generate constants.py (may need bounds.h)

#####
# 1) Generate bounds.h

bounds-file := include/generated/bounds.h

always  := $(bounds-file)
targets := kernel/bounds.s

# We use internal kbuild rules to avoid the "is up to date" message from make
kernel/bounds.s: kernel/bounds.c FORCE
	$(call if_changed_dep,cc_s_c)

$(obj)/$(bounds-file): kernel/bounds.s FORCE
	$(call filechk,offsets,__LINUX_BOUNDS_H__)

#####
# 2) Generate timeconst.h

timeconst-file := include/generated/timeconst.h

targets += $(timeconst-file)

quiet_cmd_gentimeconst = GEN     $@
define cmd_gentimeconst
	(echo $(CONFIG_HZ) | bc -q $< ) > $@
endef
define filechk_gentimeconst
	(echo $(CONFIG_HZ) | bc -q $< )
endef

$(obj)/$(timeconst-file): kernel/time/timeconst.bc FORCE
	$(call filechk,gentimeconst)

#####
# 3) Generate asm-offsets.h
#

offsets-file := include/generated/asm-offsets.h

always  += $(offsets-file)
targets += arch/$(SRCARCH)/kernel/asm-offsets.s

# We use internal kbuild rules to avoid the "is up to date" message from make
arch/$(SRCARCH)/kernel/asm-offsets.s: arch/$(SRCARCH)/kernel/asm-offsets.c \
                                      $(obj)/$(timeconst-file) $(obj)/$(bounds-file) FORCE
	$(call if_changed_dep,cc_s_c)

$(obj)/$(offsets-file): arch/$(SRCARCH)/kernel/asm-offsets.s FORCE
	$(call filechk,offsets,__ASM_OFFSETS_H__)

#####
# 4) Check for missing system calls
#

always += missing-syscalls
targets += missing-syscalls

quiet_cmd_syscalls = CALL    $<
      cmd_syscalls = $(CONFIG_SHELL) $< $(CC) $(c_flags) $(missing_syscalls_flags)

missing-syscalls: scripts/checksyscalls.sh $(offsets-file) FORCE
	$(call cmd,syscalls)

#####
# 5) Generate constants for Python GDB integration
#

extra-$(CONFIG_GDB_SCRIPTS) += build_constants_py

build_constants_py: $(obj)/$(timeconst-file) $(obj)/$(bounds-file)
	@$(MAKE) $(build)=scripts/gdb/linux $@

# Keep these three files during make clean
no-clean-files := $(bounds-file) $(offsets-file) $(timeconst-file)
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