diff options
Diffstat (limited to 'include/asm-generic')
| -rw-r--r-- | include/asm-generic/bug.h | 28 | ||||
| -rw-r--r-- | include/asm-generic/vmlinux.lds.h | 44 |
2 files changed, 51 insertions, 21 deletions
diff --git a/include/asm-generic/bug.h b/include/asm-generic/bug.h index c2c9ba032d4..f2d2faf4d9a 100644 --- a/include/asm-generic/bug.h +++ b/include/asm-generic/bug.h @@ -165,10 +165,36 @@ extern void warn_slowpath_null(const char *file, const int line); #define WARN_ON_RATELIMIT(condition, state) \ WARN_ON((condition) && __ratelimit(state)) +/* + * WARN_ON_SMP() is for cases that the warning is either + * meaningless for !SMP or may even cause failures. + * This is usually used for cases that we have + * WARN_ON(!spin_is_locked(&lock)) checks, as spin_is_locked() + * returns 0 for uniprocessor settings. + * It can also be used with values that are only defined + * on SMP: + * + * struct foo { + * [...] + * #ifdef CONFIG_SMP + * int bar; + * #endif + * }; + * + * void func(struct foo *zoot) + * { + * WARN_ON_SMP(!zoot->bar); + * + * For CONFIG_SMP, WARN_ON_SMP() should act the same as WARN_ON(), + * and should be a nop and return false for uniprocessor. + * + * if (WARN_ON_SMP(x)) returns true only when CONFIG_SMP is set + * and x is true. + */ #ifdef CONFIG_SMP # define WARN_ON_SMP(x) WARN_ON(x) #else -# define WARN_ON_SMP(x) do { } while (0) +# define WARN_ON_SMP(x) ({0;}) #endif #endif diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index f301cea5ca2..ebdaafa866a 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -688,6 +688,28 @@ } /** + * PERCPU_INPUT - the percpu input sections + * @cacheline: cacheline size + * + * The core percpu section names and core symbols which do not rely + * directly upon load addresses. + * + * @cacheline is used to align subsections to avoid false cacheline + * sharing between subsections for different purposes. + */ +#define PERCPU_INPUT(cacheline) \ + VMLINUX_SYMBOL(__per_cpu_start) = .; \ + *(.data..percpu..first) \ + . = ALIGN(PAGE_SIZE); \ + *(.data..percpu..page_aligned) \ + . = ALIGN(cacheline); \ + *(.data..percpu..readmostly) \ + . = ALIGN(cacheline); \ + *(.data..percpu) \ + *(.data..percpu..shared_aligned) \ + VMLINUX_SYMBOL(__per_cpu_end) = .; + +/** * PERCPU_VADDR - define output section for percpu area * @cacheline: cacheline size * @vaddr: explicit base address (optional) @@ -715,16 +737,7 @@ VMLINUX_SYMBOL(__per_cpu_load) = .; \ .data..percpu vaddr : AT(VMLINUX_SYMBOL(__per_cpu_load) \ - LOAD_OFFSET) { \ - VMLINUX_SYMBOL(__per_cpu_start) = .; \ - *(.data..percpu..first) \ - . = ALIGN(PAGE_SIZE); \ - *(.data..percpu..page_aligned) \ - . = ALIGN(cacheline); \ - *(.data..percpu..readmostly) \ - . = ALIGN(cacheline); \ - *(.data..percpu) \ - *(.data..percpu..shared_aligned) \ - VMLINUX_SYMBOL(__per_cpu_end) = .; \ + PERCPU_INPUT(cacheline) \ } phdr \ . = VMLINUX_SYMBOL(__per_cpu_load) + SIZEOF(.data..percpu); @@ -744,16 +757,7 @@ . = ALIGN(PAGE_SIZE); \ .data..percpu : AT(ADDR(.data..percpu) - LOAD_OFFSET) { \ VMLINUX_SYMBOL(__per_cpu_load) = .; \ - VMLINUX_SYMBOL(__per_cpu_start) = .; \ - *(.data..percpu..first) \ - . = ALIGN(PAGE_SIZE); \ - *(.data..percpu..page_aligned) \ - . = ALIGN(cacheline); \ - *(.data..percpu..readmostly) \ - . = ALIGN(cacheline); \ - *(.data..percpu) \ - *(.data..percpu..shared_aligned) \ - VMLINUX_SYMBOL(__per_cpu_end) = .; \ + PERCPU_INPUT(cacheline) \ } |