From 13a0c3c269b223f60abfac8a9811d77111a8b4ba Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Fri, 26 Dec 2008 02:05:47 -0800 Subject: sparseirq: work around compiler optimizing away __weak functions Impact: fix panic on null pointer with sparseirq Some GCC versions seem to inline the weak global function, when that function is empty. Work it around, by making the functions return a (dummy) integer. Signed-off-by: Yinghai Signed-off-by: Ingo Molnar --- init/main.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'init/main.c') diff --git a/init/main.c b/init/main.c index c1f999a3cf31..c314aa15370e 100644 --- a/init/main.c +++ b/init/main.c @@ -539,13 +539,14 @@ void __init __weak thread_info_cache_init(void) { } -void __init __weak arch_early_irq_init(void) +int __init __weak arch_early_irq_init(void) { + return 0; } -void __init __weak early_irq_init(void) +int __init __weak early_irq_init(void) { - arch_early_irq_init(); + return arch_early_irq_init(); } asmlinkage void __init start_kernel(void) -- cgit v1.2.3 From 43a256322ac1fc105c181b3cade3b9bfc0b63ca1 Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Sun, 28 Dec 2008 16:01:13 -0800 Subject: sparseirq: move __weak symbols into separate compilation unit GCC has a bug with __weak alias functions: if the functions are in the same compilation unit as their call site, GCC can decide to inline them - and thus rob the linker of the opportunity to override the weak alias with the real thing. So move all the IRQ handling related __weak symbols to kernel/irq/chip.c. Signed-off-by: Yinghai Lu Signed-off-by: Ingo Molnar --- include/linux/interrupt.h | 6 ++++++ include/linux/irq.h | 3 --- init/main.c | 10 ---------- kernel/irq/manage.c | 9 --------- kernel/softirq.c | 20 ++++++++++++++++++++ 5 files changed, 26 insertions(+), 22 deletions(-) (limited to 'init/main.c') diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h index 777f89e00b4a..d9a370325ae2 100644 --- a/include/linux/interrupt.h +++ b/include/linux/interrupt.h @@ -467,4 +467,10 @@ static inline void init_irq_proc(void) int show_interrupts(struct seq_file *p, void *v); +struct irq_desc; + +extern int early_irq_init(void); +extern int arch_early_irq_init(void); +extern int arch_init_chip_data(struct irq_desc *desc, int cpu); + #endif diff --git a/include/linux/irq.h b/include/linux/irq.h index 0e40af4bac40..d64a6d49bdef 100644 --- a/include/linux/irq.h +++ b/include/linux/irq.h @@ -193,9 +193,6 @@ struct irq_desc { const char *name; } ____cacheline_internodealigned_in_smp; -extern int early_irq_init(void); -extern int arch_early_irq_init(void); -extern int arch_init_chip_data(struct irq_desc *desc, int cpu); extern void arch_init_copy_chip_data(struct irq_desc *old_desc, struct irq_desc *desc, int cpu); extern void arch_free_chip_data(struct irq_desc *old_desc, struct irq_desc *desc); diff --git a/init/main.c b/init/main.c index c314aa15370e..2c183abbf61c 100644 --- a/init/main.c +++ b/init/main.c @@ -539,16 +539,6 @@ void __init __weak thread_info_cache_init(void) { } -int __init __weak arch_early_irq_init(void) -{ - return 0; -} - -int __init __weak early_irq_init(void) -{ - return arch_early_irq_init(); -} - asmlinkage void __init start_kernel(void) { char * command_line; diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index c2741b02ad38..46953a06f4a8 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -261,15 +261,6 @@ void enable_irq(unsigned int irq) } EXPORT_SYMBOL(enable_irq); -/* - * [ Not in kernel/irq/handle.c, so that GCC does not - * inline the __weak alias: ] - */ -int __weak arch_init_chip_data(struct irq_desc *desc, int cpu) -{ - return 0; -} - static int set_irq_wake_real(unsigned int irq, unsigned int on) { struct irq_desc *desc = irq_to_desc(irq); diff --git a/kernel/softirq.c b/kernel/softirq.c index e7c69a720d69..daf46358d2dd 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -797,3 +797,23 @@ int on_each_cpu(void (*func) (void *info), void *info, int wait) } EXPORT_SYMBOL(on_each_cpu); #endif + +/* + * [ These __weak aliases are kept in a separate compilation unit, so that + * GCC does not inline them incorrectly. ] + */ + +int __init __weak early_irq_init(void) +{ + return 0; +} + +int __init __weak arch_early_irq_init(void) +{ + return 0; +} + +int __weak arch_init_chip_data(struct irq_desc *desc, int cpu) +{ + return 0; +} -- cgit v1.2.3 From 915441b601e6662e79f6c958e7be307967a96977 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Thu, 1 Jan 2009 10:12:15 +1030 Subject: cpumask: Use accessors code in core Impact: use new API cpu_*_map are going away in favour of cpu_*_mask, but const pointers. So we have accessors where we really do want to frob them. Archs will also need the (trivial) conversion before we can finally remove cpu_*_map. Signed-off-by: Rusty Russell Signed-off-by: Mike Travis --- init/main.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'init/main.c') diff --git a/init/main.c b/init/main.c index 2a7ce0f8e453..84d3732c0ce5 100644 --- a/init/main.c +++ b/init/main.c @@ -527,9 +527,9 @@ static void __init boot_cpu_init(void) { int cpu = smp_processor_id(); /* Mark the boot cpu "present", "online" etc for SMP and UP case */ - cpu_set(cpu, cpu_online_map); - cpu_set(cpu, cpu_present_map); - cpu_set(cpu, cpu_possible_map); + set_cpu_online(cpu, true); + set_cpu_present(cpu, true); + set_cpu_possible(cpu, true); } void __init __weak smp_setup_processor_id(void) -- cgit v1.2.3 From e0c0ba736547e81c4f986ce192307c549d214167 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Thu, 1 Jan 2009 10:12:19 +1030 Subject: cpumask: Use find_last_bit() Impact: cleanup There's one obvious place to use it: to find the highest possible cpu. Signed-off-by: Rusty Russell --- init/main.c | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-) (limited to 'init/main.c') diff --git a/init/main.c b/init/main.c index 84d3732c0ce5..546ebd2f44ba 100644 --- a/init/main.c +++ b/init/main.c @@ -380,12 +380,7 @@ EXPORT_SYMBOL(nr_cpu_ids); /* An arch may set nr_cpu_ids earlier if needed, so this would be redundant */ static void __init setup_nr_cpu_ids(void) { - int cpu, highest_cpu = 0; - - for_each_possible_cpu(cpu) - highest_cpu = cpu; - - nr_cpu_ids = highest_cpu + 1; + nr_cpu_ids = find_last_bit(cpumask_bits(cpu_possible_mask),NR_CPUS) + 1; } #ifndef CONFIG_HAVE_SETUP_PER_CPU_AREA -- cgit v1.2.3 From 609e5b71d0eca163df017ecfcf917b149875e744 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Fri, 2 Jan 2009 16:16:16 +0100 Subject: kbuild: Remove gcc 4.1.0 quirk from init/main.c Impact: cleanup We now have a cleaner check for gcc 4.1.0/4.1.1 trouble in include/linux/compiler-gcc4.h, so remove the 4.1.0 quirk from init/main.c. Reported-by: Bartlomiej Zolnierkiewicz Signed-off-by: Ingo Molnar Acked-by: Sam Ravnborg Signed-off-by: Linus Torvalds --- init/main.c | 9 --------- 1 file changed, 9 deletions(-) (limited to 'init/main.c') diff --git a/init/main.c b/init/main.c index f5e64f20d2b0..ad8f9f53f8d1 100644 --- a/init/main.c +++ b/init/main.c @@ -75,15 +75,6 @@ #include #endif -/* - * This is one of the first .c files built. Error out early if we have compiler - * trouble. - */ - -#if __GNUC__ == 4 && __GNUC_MINOR__ == 1 && __GNUC_PATCHLEVEL__ == 0 -#warning gcc-4.1.0 is known to miscompile the kernel. A different compiler version is recommended. -#endif - static int kernel_init(void *); extern void init_IRQ(void); -- cgit v1.2.3