Merge branch 'arch-hexagon' into no-rebases (42472a74) · Commits · 戴 / test

arch/hexagon/Kconfig

+2 −0

Original line number	Diff line number	Diff line
		@@ -31,6 +31,8 @@ config HEXAGON
		select GENERIC_CLOCKEVENTS
		select GENERIC_CLOCKEVENTS_BROADCAST
		select MODULES_USE_ELF_RELA
		select GENERIC_KERNEL_THREAD
		select GENERIC_KERNEL_EXECVE
		---help---
		Qualcomm Hexagon is a processor architecture designed for high
		performance and low power across a wide variety of applications.

arch/hexagon/include/asm/processor.h

+0 −1

Original line number	Diff line number	Diff line
		@@ -34,7 +34,6 @@
		struct task_struct;

		/* this is defined in arch/process.c */
		extern pid_t kernel_thread(int (fn)(void ), void * arg, unsigned long flags);
		extern unsigned long thread_saved_pc(struct task_struct *tsk);

		extern void start_thread(struct pt_regs *, unsigned long, unsigned long);

arch/hexagon/include/asm/ptrace.h

+4 −0

Original line number	Diff line number	Diff line
		@@ -32,4 +32,8 @@
		extern int regs_query_register_offset(const char *name);
		extern const char *regs_query_register_name(unsigned int offset);

		#define current_pt_regs() \
		((struct pt_regs *) \
		((unsigned long)current_thread_info() + THREAD_SIZE) - 1)

		#endif

arch/hexagon/include/asm/unistd.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -27,5 +27,6 @@
		*/

		#define sys_mmap2 sys_mmap_pgoff
		#define __ARCH_WANT_SYS_EXECVE

		#include <asm-generic/unistd.h>

arch/hexagon/kernel/process.c

+32 −70

Original line number	Diff line number	Diff line
		@@ -25,33 +25,6 @@
		#include <linux/uaccess.h>
		#include <linux/slab.h>

		/*
		* Kernel thread creation. The desired kernel function is "wrapped"
		* in the kernel_thread_helper function, which does cleanup
		* afterwards.
		*/
		static void __noreturn kernel_thread_helper(void arg, int (fn)(void *))
		{
		do_exit(fn(arg));
		}

		int kernel_thread(int (fn)(void ), void *arg, unsigned long flags)
		{
		struct pt_regs regs;

		memset(&regs, 0, sizeof(regs));
		/*
		* Yes, we're exploting illicit knowledge of the ABI here.
		*/
		regs.r00 = (unsigned long) arg;
		regs.r01 = (unsigned long) fn;
		pt_set_elr(&regs, (unsigned long)kernel_thread_helper);
		pt_set_kmode(&regs);

		return do_fork(flags\|CLONE_VM\|CLONE_UNTRACED, 0, &regs, 0, NULL, NULL);
		}
		EXPORT_SYMBOL(kernel_thread);

		/*
		* Program thread launch. Often defined as a macro in processor.h,
		* but we're shooting for a small footprint and it's not an inner-loop
		@@ -114,7 +87,7 @@ unsigned long thread_saved_pc(struct task_struct *tsk)
		* Copy architecture-specific thread state
		*/
		int copy_thread(unsigned long clone_flags, unsigned long usp,
		unsigned long unused, struct task_struct *p,
		unsigned long arg, struct task_struct *p,
		struct pt_regs *regs)
		{
		struct thread_info *ti = task_thread_info(p);
		@@ -125,19 +98,28 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
		childregs = (struct pt_regs *) (((unsigned long) ti + THREAD_SIZE) -
		sizeof(*childregs));

		memcpy(childregs, regs, sizeof(*childregs));
		ti->regs = childregs;

		/*
		* Establish kernel stack pointer and initial PC for new thread
		* Note that unlike the usual situation, we do not copy the
		* parent's callee-saved here; those are in pt_regs and whatever
		* we leave here will be overridden on return to userland.
		*/
		ss = (struct hexagon_switch_stack *) ((unsigned long) childregs -
		sizeof(*ss));
		ss->lr = (unsigned long)ret_from_fork;
		p->thread.switch_sp = ss;
		if (unlikely(p->flags & PF_KTHREAD)) {
		memset(childregs, 0, sizeof(struct pt_regs));
		/* r24 <- fn, r25 <- arg */
		ss->r2524 = usp \| ((u64)arg << 32);
		pt_set_kmode(childregs);
		return 0;
		}
		memcpy(childregs, regs, sizeof(*childregs));
		ss->r2524 = 0;

		/* If User mode thread, set pt_reg stack pointer as per parameter */
		if (user_mode(childregs)) {
		pt_set_rte_sp(childregs, usp);

		/* Child sees zero return value */
		@@ -160,26 +142,6 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
		* this point in the fork process
		* Might also want to set things like ti->addr_limit
		*/
		} else {
		/*
		* If kernel thread, resume stack is kernel stack base.
		* Note that this is pointer arithmetic on pt_regs *
		*/
		pt_set_rte_sp(childregs, (unsigned long)(childregs + 1));
		/*
		* We need the current thread_info fast path pointer
		* set up in pt_regs. The register to be used is
		* parametric for assembler code, but the mechanism
		* doesn't drop neatly into C. Needs to be fixed.
		*/
		childregs->THREADINFO_REG = (unsigned long) ti;
		}

		/*
		* thread_info pointer is pulled out of task_struct "stack"
		* field on switch_to.
		*/
		p->stack = (void *)ti;

		return 0;
		}

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