| Message ID | 20210414165808.458a3d11@xhacker.debian (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | init: consolidate trap_init() | expand |
Le 14/04/2021 à 10:58, Jisheng Zhang a écrit : > Many architectures implement the trap_init() as NOP, since there is > no such default for trap_init(), this empty stub is duplicated among > these architectures. Provide a generic but weak NOP implementation > to drop the empty stubs of trap_init() in these architectures. You define the weak function in the __init section. Most but not all architectures had it in __init section. And the remaining ones may not be defined in __init section. For instance look at the one in alpha architecture. Have you checked that it is not a problem ? It would be good to say something about it in the commit description. > > Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com> > --- > arch/arc/kernel/traps.c | 5 ----- > arch/arm/kernel/traps.c | 5 ----- > arch/h8300/kernel/traps.c | 13 ------------- > arch/hexagon/kernel/traps.c | 4 ---- > arch/nds32/kernel/traps.c | 5 ----- > arch/nios2/kernel/traps.c | 5 ----- > arch/openrisc/kernel/traps.c | 5 ----- > arch/parisc/kernel/traps.c | 4 ---- > arch/powerpc/kernel/traps.c | 5 ----- > arch/riscv/kernel/traps.c | 5 ----- > arch/um/kernel/trap.c | 4 ---- > init/main.c | 2 ++ > 12 files changed, 2 insertions(+), 60 deletions(-) > > diff --git a/init/main.c b/init/main.c > index 53b278845b88..4bdbe2928530 100644 > --- a/init/main.c > +++ b/init/main.c > @@ -790,6 +790,8 @@ static inline void initcall_debug_enable(void) > } > #endif > > +void __init __weak trap_init(void) { } > + I think in a C file we don't try to save space as much as in a header file. I would prefer something like: void __init __weak trap_init(void) { } > /* Report memory auto-initialization states for this boot. */ > static void __init report_meminit(void) > { >
On Wed, 14 Apr 2021 11:10:42 +0200 Christophe Leroy <christophe.leroy@csgroup.eu> wrote: > > Le 14/04/2021 à 10:58, Jisheng Zhang a écrit : > > Many architectures implement the trap_init() as NOP, since there is > > no such default for trap_init(), this empty stub is duplicated among > > these architectures. Provide a generic but weak NOP implementation > > to drop the empty stubs of trap_init() in these architectures. > > You define the weak function in the __init section. > > Most but not all architectures had it in __init section. > > And the remaining ones may not be defined in __init section. For instance look at the one in alpha > architecture. > > Have you checked that it is not a problem ? It would be good to say something about it in the commit > description. For those non-nop platforms, I can only test x86/arm64/, but both has __init mark. I'm not sure whether this is a problem for alpha etc. Maybe I can check which section the trap_init() sits. Or to avoid any possible regression, I can add __init mark to those remaining ones without it in preparation patches. > > > > > > Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com> > > --- > > arch/arc/kernel/traps.c | 5 ----- > > arch/arm/kernel/traps.c | 5 ----- > > arch/h8300/kernel/traps.c | 13 ------------- > > arch/hexagon/kernel/traps.c | 4 ---- > > arch/nds32/kernel/traps.c | 5 ----- > > arch/nios2/kernel/traps.c | 5 ----- > > arch/openrisc/kernel/traps.c | 5 ----- > > arch/parisc/kernel/traps.c | 4 ---- > > arch/powerpc/kernel/traps.c | 5 ----- > > arch/riscv/kernel/traps.c | 5 ----- > > arch/um/kernel/trap.c | 4 ---- > > init/main.c | 2 ++ > > 12 files changed, 2 insertions(+), 60 deletions(-) > > > > diff --git a/init/main.c b/init/main.c > > index 53b278845b88..4bdbe2928530 100644 > > --- a/init/main.c > > +++ b/init/main.c > > @@ -790,6 +790,8 @@ static inline void initcall_debug_enable(void) > > } > > #endif > > > > +void __init __weak trap_init(void) { } > > + > > I think in a C file we don't try to save space as much as in a header file. > This is to follow most weak NOP implementations in init/main.c to make the style unified in the same file. I'm not sure which is better. > I would prefer something like: > > > void __init __weak trap_init(void) > { > } > > > > /* Report memory auto-initialization states for this boot. */ > > static void __init report_meminit(void) > > { > >
On Wed, 14 Apr 2021 17:27:57 +0800 Jisheng Zhang <Jisheng.Zhang@synaptics.com> wrote: > CAUTION: Email originated externally, do not click links or open attachments unless you recognize the sender and know the content is safe. > > > On Wed, 14 Apr 2021 11:10:42 +0200 > Christophe Leroy <christophe.leroy@csgroup.eu> wrote: > > > > > Le 14/04/2021 à 10:58, Jisheng Zhang a écrit : > > > Many architectures implement the trap_init() as NOP, since there is > > > no such default for trap_init(), this empty stub is duplicated among > > > these architectures. Provide a generic but weak NOP implementation > > > to drop the empty stubs of trap_init() in these architectures. > > > > You define the weak function in the __init section. > > > > Most but not all architectures had it in __init section. > > > > And the remaining ones may not be defined in __init section. For instance look at the one in alpha > > architecture. > > > > Have you checked that it is not a problem ? It would be good to say something about it in the commit > > description. > > For those non-nop platforms, I can only test x86/arm64/, but both has > __init mark. I'm not sure whether this is a problem for alpha etc. Maybe > I can check which section the trap_init() sits. Or to avoid any possible > regression, I can add __init mark to those remaining ones without it in > preparation patches. > Hi, I found only three platforms don't have the __init marker for trap_init(), I will add the __init marker in three preparation patches in new version. thanks
diff --git a/arch/arc/kernel/traps.c b/arch/arc/kernel/traps.c index 57235e5c0cea..6b83e3f2b41c 100644 --- a/arch/arc/kernel/traps.c +++ b/arch/arc/kernel/traps.c @@ -20,11 +20,6 @@ #include <asm/unaligned.h> #include <asm/kprobes.h> -void __init trap_init(void) -{ - return; -} - void die(const char *str, struct pt_regs *regs, unsigned long address) { show_kernel_fault_diag(str, regs, address); diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c index 17d5a785df28..9baccef20392 100644 --- a/arch/arm/kernel/traps.c +++ b/arch/arm/kernel/traps.c @@ -780,11 +780,6 @@ void abort(void) panic("Oops failed to kill thread"); } -void __init trap_init(void) -{ - return; -} - #ifdef CONFIG_KUSER_HELPERS static void __init kuser_init(void *vectors) { diff --git a/arch/h8300/kernel/traps.c b/arch/h8300/kernel/traps.c index 5d8b969cd8f3..c3a3ebf77fbb 100644 --- a/arch/h8300/kernel/traps.c +++ b/arch/h8300/kernel/traps.c @@ -30,19 +30,6 @@ static DEFINE_SPINLOCK(die_lock); -/* - * this must be called very early as the kernel might - * use some instruction that are emulated on the 060 - */ - -void __init base_trap_init(void) -{ -} - -void __init trap_init(void) -{ -} - asmlinkage void set_esp0(unsigned long ssp) { current->thread.esp0 = ssp; diff --git a/arch/hexagon/kernel/traps.c b/arch/hexagon/kernel/traps.c index 904134b37232..edfc35dafeb1 100644 --- a/arch/hexagon/kernel/traps.c +++ b/arch/hexagon/kernel/traps.c @@ -28,10 +28,6 @@ #define TRAP_SYSCALL 1 #define TRAP_DEBUG 0xdb -void __init trap_init(void) -{ -} - #ifdef CONFIG_GENERIC_BUG /* Maybe should resemble arch/sh/kernel/traps.c ?? */ int is_valid_bugaddr(unsigned long addr) diff --git a/arch/nds32/kernel/traps.c b/arch/nds32/kernel/traps.c index ee0d9ae192a5..f06421c645af 100644 --- a/arch/nds32/kernel/traps.c +++ b/arch/nds32/kernel/traps.c @@ -183,11 +183,6 @@ void __pgd_error(const char *file, int line, unsigned long val) } extern char *exception_vector, *exception_vector_end; -void __init trap_init(void) -{ - return; -} - void __init early_trap_init(void) { unsigned long ivb = 0; diff --git a/arch/nios2/kernel/traps.c b/arch/nios2/kernel/traps.c index b172da4eb1a9..596986a74a26 100644 --- a/arch/nios2/kernel/traps.c +++ b/arch/nios2/kernel/traps.c @@ -105,11 +105,6 @@ void show_stack(struct task_struct *task, unsigned long *stack, printk("%s\n", loglvl); } -void __init trap_init(void) -{ - /* Nothing to do here */ -} - /* Breakpoint handler */ asmlinkage void breakpoint_c(struct pt_regs *fp) { diff --git a/arch/openrisc/kernel/traps.c b/arch/openrisc/kernel/traps.c index 4d61333c2623..aa1e709405ac 100644 --- a/arch/openrisc/kernel/traps.c +++ b/arch/openrisc/kernel/traps.c @@ -231,11 +231,6 @@ void unhandled_exception(struct pt_regs *regs, int ea, int vector) die("Oops", regs, 9); } -void __init trap_init(void) -{ - /* Nothing needs to be done */ -} - asmlinkage void do_trap(struct pt_regs *regs, unsigned long address) { force_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)regs->pc); diff --git a/arch/parisc/kernel/traps.c b/arch/parisc/kernel/traps.c index 8d8441d4562a..747c328fb886 100644 --- a/arch/parisc/kernel/traps.c +++ b/arch/parisc/kernel/traps.c @@ -859,7 +859,3 @@ void __init early_trap_init(void) initialize_ivt(&fault_vector_20); } - -void __init trap_init(void) -{ -} diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index a44a30b0688c..e952bee89684 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -2207,11 +2207,6 @@ DEFINE_INTERRUPT_HANDLER(kernel_bad_stack) die("Bad kernel stack pointer", regs, SIGABRT); } -void __init trap_init(void) -{ -} - - #ifdef CONFIG_PPC_EMULATED_STATS #define WARN_EMULATED_SETUP(type) .type = { .name = #type } diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c index 0879b5df11b9..b3f3d84de779 100644 --- a/arch/riscv/kernel/traps.c +++ b/arch/riscv/kernel/traps.c @@ -194,8 +194,3 @@ int is_valid_bugaddr(unsigned long pc) return ((insn & __COMPRESSED_INSN_MASK) == __BUG_INSN_16); } #endif /* CONFIG_GENERIC_BUG */ - -/* stvec & scratch is already set from head.S */ -void trap_init(void) -{ -} diff --git a/arch/um/kernel/trap.c b/arch/um/kernel/trap.c index ad12f78bda7e..3198c4767387 100644 --- a/arch/um/kernel/trap.c +++ b/arch/um/kernel/trap.c @@ -311,7 +311,3 @@ void winch(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs) { do_IRQ(WINCH_IRQ, regs); } - -void trap_init(void) -{ -} diff --git a/init/main.c b/init/main.c index 53b278845b88..4bdbe2928530 100644 --- a/init/main.c +++ b/init/main.c @@ -790,6 +790,8 @@ static inline void initcall_debug_enable(void) } #endif +void __init __weak trap_init(void) { } + /* Report memory auto-initialization states for this boot. */ static void __init report_meminit(void) {
Many architectures implement the trap_init() as NOP, since there is no such default for trap_init(), this empty stub is duplicated among these architectures. Provide a generic but weak NOP implementation to drop the empty stubs of trap_init() in these architectures. Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com> --- arch/arc/kernel/traps.c | 5 ----- arch/arm/kernel/traps.c | 5 ----- arch/h8300/kernel/traps.c | 13 ------------- arch/hexagon/kernel/traps.c | 4 ---- arch/nds32/kernel/traps.c | 5 ----- arch/nios2/kernel/traps.c | 5 ----- arch/openrisc/kernel/traps.c | 5 ----- arch/parisc/kernel/traps.c | 4 ---- arch/powerpc/kernel/traps.c | 5 ----- arch/riscv/kernel/traps.c | 5 ----- arch/um/kernel/trap.c | 4 ---- init/main.c | 2 ++ 12 files changed, 2 insertions(+), 60 deletions(-)