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Diffstat (limited to 'arch/xtensa/kernel/process.c')
-rw-r--r--arch/xtensa/kernel/process.c171
1 files changed, 122 insertions, 49 deletions
diff --git a/arch/xtensa/kernel/process.c b/arch/xtensa/kernel/process.c
index 060165340612..94d43f44be13 100644
--- a/arch/xtensa/kernel/process.c
+++ b/arch/xtensa/kernel/process.c
@@ -47,6 +47,8 @@
#include <asm/asm-offsets.h>
#include <asm/regs.h>
#include <asm/hw_breakpoint.h>
+#include <asm/sections.h>
+#include <asm/traps.h>
extern void ret_from_fork(void);
extern void ret_from_kernel_thread(void);
@@ -63,52 +65,114 @@ EXPORT_SYMBOL(__stack_chk_guard);
#if XTENSA_HAVE_COPROCESSORS
-void coprocessor_release_all(struct thread_info *ti)
+void local_coprocessors_flush_release_all(void)
{
- unsigned long cpenable;
- int i;
+ struct thread_info **coprocessor_owner;
+ struct thread_info *unique_owner[XCHAL_CP_MAX];
+ int n = 0;
+ int i, j;
- /* Make sure we don't switch tasks during this operation. */
+ coprocessor_owner = this_cpu_ptr(&exc_table)->coprocessor_owner;
+ xtensa_set_sr(XCHAL_CP_MASK, cpenable);
- preempt_disable();
+ for (i = 0; i < XCHAL_CP_MAX; i++) {
+ struct thread_info *ti = coprocessor_owner[i];
- /* Walk through all cp owners and release it for the requested one. */
+ if (ti) {
+ coprocessor_flush(ti, i);
- cpenable = ti->cpenable;
+ for (j = 0; j < n; j++)
+ if (unique_owner[j] == ti)
+ break;
+ if (j == n)
+ unique_owner[n++] = ti;
- for (i = 0; i < XCHAL_CP_MAX; i++) {
- if (coprocessor_owner[i] == ti) {
- coprocessor_owner[i] = 0;
- cpenable &= ~(1 << i);
+ coprocessor_owner[i] = NULL;
}
}
+ for (i = 0; i < n; i++) {
+ /* pairs with memw (1) in fast_coprocessor and memw in switch_to */
+ smp_wmb();
+ unique_owner[i]->cpenable = 0;
+ }
+ xtensa_set_sr(0, cpenable);
+}
+
+static void local_coprocessor_release_all(void *info)
+{
+ struct thread_info *ti = info;
+ struct thread_info **coprocessor_owner;
+ int i;
- ti->cpenable = cpenable;
+ coprocessor_owner = this_cpu_ptr(&exc_table)->coprocessor_owner;
+
+ /* Walk through all cp owners and release it for the requested one. */
+
+ for (i = 0; i < XCHAL_CP_MAX; i++) {
+ if (coprocessor_owner[i] == ti)
+ coprocessor_owner[i] = NULL;
+ }
+ /* pairs with memw (1) in fast_coprocessor and memw in switch_to */
+ smp_wmb();
+ ti->cpenable = 0;
if (ti == current_thread_info())
xtensa_set_sr(0, cpenable);
+}
- preempt_enable();
+void coprocessor_release_all(struct thread_info *ti)
+{
+ if (ti->cpenable) {
+ /* pairs with memw (2) in fast_coprocessor */
+ smp_rmb();
+ smp_call_function_single(ti->cp_owner_cpu,
+ local_coprocessor_release_all,
+ ti, true);
+ }
}
-void coprocessor_flush_all(struct thread_info *ti)
+static void local_coprocessor_flush_all(void *info)
{
- unsigned long cpenable, old_cpenable;
+ struct thread_info *ti = info;
+ struct thread_info **coprocessor_owner;
+ unsigned long old_cpenable;
int i;
- preempt_disable();
-
- old_cpenable = xtensa_get_sr(cpenable);
- cpenable = ti->cpenable;
- xtensa_set_sr(cpenable, cpenable);
+ coprocessor_owner = this_cpu_ptr(&exc_table)->coprocessor_owner;
+ old_cpenable = xtensa_xsr(ti->cpenable, cpenable);
for (i = 0; i < XCHAL_CP_MAX; i++) {
- if ((cpenable & 1) != 0 && coprocessor_owner[i] == ti)
+ if (coprocessor_owner[i] == ti)
coprocessor_flush(ti, i);
- cpenable >>= 1;
}
xtensa_set_sr(old_cpenable, cpenable);
+}
+
+void coprocessor_flush_all(struct thread_info *ti)
+{
+ if (ti->cpenable) {
+ /* pairs with memw (2) in fast_coprocessor */
+ smp_rmb();
+ smp_call_function_single(ti->cp_owner_cpu,
+ local_coprocessor_flush_all,
+ ti, true);
+ }
+}
+
+static void local_coprocessor_flush_release_all(void *info)
+{
+ local_coprocessor_flush_all(info);
+ local_coprocessor_release_all(info);
+}
- preempt_enable();
+void coprocessor_flush_release_all(struct thread_info *ti)
+{
+ if (ti->cpenable) {
+ /* pairs with memw (2) in fast_coprocessor */
+ smp_rmb();
+ smp_call_function_single(ti->cp_owner_cpu,
+ local_coprocessor_flush_release_all,
+ ti, true);
+ }
}
#endif
@@ -120,6 +184,7 @@ void coprocessor_flush_all(struct thread_info *ti)
void arch_cpu_idle(void)
{
platform_idle();
+ raw_local_irq_disable();
}
/*
@@ -140,8 +205,7 @@ void flush_thread(void)
{
#if XTENSA_HAVE_COPROCESSORS
struct thread_info *ti = current_thread_info();
- coprocessor_flush_all(ti);
- coprocessor_release_all(ti);
+ coprocessor_flush_release_all(ti);
#endif
flush_ptrace_hw_breakpoint(current);
}
@@ -201,23 +265,31 @@ int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
* involved. Much simpler to just not copy those live frames across.
*/
-int copy_thread(unsigned long clone_flags, unsigned long usp_thread_fn,
- unsigned long thread_fn_arg, struct task_struct *p,
- unsigned long tls)
+int copy_thread(struct task_struct *p, const struct kernel_clone_args *args)
{
+ u64 clone_flags = args->flags;
+ unsigned long usp_thread_fn = args->stack;
+ unsigned long tls = args->tls;
struct pt_regs *childregs = task_pt_regs(p);
#if (XTENSA_HAVE_COPROCESSORS || XTENSA_HAVE_IO_PORTS)
struct thread_info *ti;
#endif
+#if defined(__XTENSA_WINDOWED_ABI__)
/* Create a call4 dummy-frame: a0 = 0, a1 = childregs. */
SPILL_SLOT(childregs, 1) = (unsigned long)childregs;
SPILL_SLOT(childregs, 0) = 0;
p->thread.sp = (unsigned long)childregs;
+#elif defined(__XTENSA_CALL0_ABI__)
+ /* Reserve 16 bytes for the _switch_to stack frame. */
+ p->thread.sp = (unsigned long)childregs - 16;
+#else
+#error Unsupported Xtensa ABI
+#endif
- if (!(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
+ if (!args->fn) {
struct pt_regs *regs = current_pt_regs();
unsigned long usp = usp_thread_fn ?
usp_thread_fn : regs->areg[1];
@@ -225,10 +297,6 @@ int copy_thread(unsigned long clone_flags, unsigned long usp_thread_fn,
p->thread.ra = MAKE_RA_FOR_CALL(
(unsigned long)ret_from_fork, 0x1);
- /* This does not copy all the regs.
- * In a bout of brilliance or madness,
- * ARs beyond a0-a15 exist past the end of the struct.
- */
*childregs = *regs;
childregs->areg[1] = usp;
childregs->areg[2] = 0;
@@ -258,25 +326,33 @@ int copy_thread(unsigned long clone_flags, unsigned long usp_thread_fn,
childregs->wmask = 1;
childregs->windowstart = 1;
childregs->windowbase = 0;
- } else {
- int len = childregs->wmask & ~0xf;
- memcpy(&childregs->areg[XCHAL_NUM_AREGS - len/4],
- &regs->areg[XCHAL_NUM_AREGS - len/4], len);
}
- childregs->syscall = regs->syscall;
-
if (clone_flags & CLONE_SETTLS)
childregs->threadptr = tls;
} else {
p->thread.ra = MAKE_RA_FOR_CALL(
(unsigned long)ret_from_kernel_thread, 1);
- /* pass parameters to ret_from_kernel_thread:
- * a2 = thread_fn, a3 = thread_fn arg
+ /* pass parameters to ret_from_kernel_thread: */
+#if defined(__XTENSA_WINDOWED_ABI__)
+ /*
+ * a2 = thread_fn, a3 = thread_fn arg.
+ * Window underflow will load registers from the
+ * spill slots on the stack on return from _switch_to.
+ */
+ SPILL_SLOT(childregs, 2) = (unsigned long)args->fn;
+ SPILL_SLOT(childregs, 3) = (unsigned long)args->fn_arg;
+#elif defined(__XTENSA_CALL0_ABI__)
+ /*
+ * a12 = thread_fn, a13 = thread_fn arg.
+ * _switch_to epilogue will load registers from the stack.
*/
- SPILL_SLOT(childregs, 3) = thread_fn_arg;
- SPILL_SLOT(childregs, 2) = usp_thread_fn;
+ ((unsigned long *)p->thread.sp)[0] = (unsigned long)args->fn;
+ ((unsigned long *)p->thread.sp)[1] = (unsigned long)args->fn_arg;
+#else
+#error Unsupported Xtensa ABI
+#endif
/* Childregs are only used when we're going to userspace
* in which case start_thread will set them up.
@@ -298,17 +374,14 @@ int copy_thread(unsigned long clone_flags, unsigned long usp_thread_fn,
* These bracket the sleeping functions..
*/
-unsigned long get_wchan(struct task_struct *p)
+unsigned long __get_wchan(struct task_struct *p)
{
unsigned long sp, pc;
unsigned long stack_page = (unsigned long) task_stack_page(p);
int count = 0;
- if (!p || p == current || task_is_running(p))
- return 0;
-
sp = p->thread.sp;
- pc = MAKE_PC_FROM_RA(p->thread.ra, p->thread.sp);
+ pc = MAKE_PC_FROM_RA(p->thread.ra, _text);
do {
if (sp < stack_page + sizeof(struct task_struct) ||
@@ -320,7 +393,7 @@ unsigned long get_wchan(struct task_struct *p)
/* Stack layout: sp-4: ra, sp-3: sp' */
- pc = MAKE_PC_FROM_RA(SPILL_SLOT(sp, 0), sp);
+ pc = MAKE_PC_FROM_RA(SPILL_SLOT(sp, 0), _text);
sp = SPILL_SLOT(sp, 1);
} while (count++ < 16);
return 0;
generated by cgit (git 2.34.1) at 2025-12-24 21:09:21 +0000