Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/include/linux/smp.h b/include/linux/smp.h
index 9fb239e..6fc856c 100644
--- a/include/linux/smp.h
+++ b/include/linux/smp.h
@@ -35,7 +35,7 @@
/*
* Call a function on all processors
*/
-int on_each_cpu(smp_call_func_t func, void *info, int wait);
+void on_each_cpu(smp_call_func_t func, void *info, int wait);
/*
* Call a function on processors specified by mask, which might include
@@ -53,6 +53,10 @@
smp_call_func_t func, void *info, bool wait,
gfp_t gfp_flags);
+void on_each_cpu_cond_mask(bool (*cond_func)(int cpu, void *info),
+ smp_call_func_t func, void *info, bool wait,
+ gfp_t gfp_flags, const struct cpumask *mask);
+
int smp_call_function_single_async(int cpu, call_single_data_t *csd);
#ifdef CONFIG_SMP
@@ -97,7 +101,7 @@
/*
* Call a function on all other processors
*/
-int smp_call_function(smp_call_func_t func, void *info, int wait);
+void smp_call_function(smp_call_func_t func, void *info, int wait);
void smp_call_function_many(const struct cpumask *mask,
smp_call_func_t func, void *info, bool wait);
@@ -140,9 +144,8 @@
* These macros fold the SMP functionality into a single CPU system
*/
#define raw_smp_processor_id() 0
-static inline int up_smp_call_function(smp_call_func_t func, void *info)
+static inline void up_smp_call_function(smp_call_func_t func, void *info)
{
- return 0;
}
#define smp_call_function(func, info, wait) \
(up_smp_call_function(func, info))
@@ -177,29 +180,46 @@
#endif /* !SMP */
-/*
- * smp_processor_id(): get the current CPU ID.
+/**
+ * raw_processor_id() - get the current (unstable) CPU id
*
- * if DEBUG_PREEMPT is enabled then we check whether it is
- * used in a preemption-safe way. (smp_processor_id() is safe
- * if it's used in a preemption-off critical section, or in
- * a thread that is bound to the current CPU.)
- *
- * NOTE: raw_smp_processor_id() is for internal use only
- * (smp_processor_id() is the preferred variant), but in rare
- * instances it might also be used to turn off false positives
- * (i.e. smp_processor_id() use that the debugging code reports but
- * which use for some reason is legal). Don't use this to hack around
- * the warning message, as your code might not work under PREEMPT.
+ * For then you know what you are doing and need an unstable
+ * CPU id.
*/
+
+/**
+ * smp_processor_id() - get the current (stable) CPU id
+ *
+ * This is the normal accessor to the CPU id and should be used
+ * whenever possible.
+ *
+ * The CPU id is stable when:
+ *
+ * - IRQs are disabled;
+ * - preemption is disabled;
+ * - the task is CPU affine.
+ *
+ * When CONFIG_DEBUG_PREEMPT; we verify these assumption and WARN
+ * when smp_processor_id() is used when the CPU id is not stable.
+ */
+
+/*
+ * Allow the architecture to differentiate between a stable and unstable read.
+ * For example, x86 uses an IRQ-safe asm-volatile read for the unstable but a
+ * regular asm read for the stable.
+ */
+#ifndef __smp_processor_id
+#define __smp_processor_id(x) raw_smp_processor_id(x)
+#endif
+
#ifdef CONFIG_DEBUG_PREEMPT
extern unsigned int debug_smp_processor_id(void);
# define smp_processor_id() debug_smp_processor_id()
#else
-# define smp_processor_id() raw_smp_processor_id()
+# define smp_processor_id() __smp_processor_id()
#endif
-#define get_cpu() ({ preempt_disable(); smp_processor_id(); })
+#define get_cpu() ({ preempt_disable(); __smp_processor_id(); })
#define put_cpu() preempt_enable()
/*