Files
nuttx/arch/arm/src/armv6-m/arm_schedulesigaction.c
Xiang Xiao 7dc0d70092 arch: Save sigdeliver into xcp in the case of signal self delevery
to avoid the infinite recusive dispatch:
*0  myhandler (signo=27, info=0xf3e38b9c, context=0x0) at ltp/testcases/open_posix_testsuite/conformance/interfaces/sigqueue/7-1.c:39
*1  0x58f1c39e in nxsig_deliver (stcb=0xf4e20f40) at signal/sig_deliver.c:167
*2  0x58fa0664 in up_schedule_sigaction (tcb=0xf4e20f40, sigdeliver=0x58f1bab5 <nxsig_deliver>) at sim/sim_schedulesigaction.c:88
*3  0x58f19907 in nxsig_queue_action (stcb=0xf4e20f40, info=0xf4049334) at signal/sig_dispatch.c:115
*4  0x58f1b089 in nxsig_tcbdispatch (stcb=0xf4e20f40, info=0xf4049334) at signal/sig_dispatch.c:435
*5  0x58f31853 in nxsig_unmask_pendingsignal () at signal/sig_unmaskpendingsignal.c:104
*6  0x58f1ca09 in nxsig_deliver (stcb=0xf4e20f40) at signal/sig_deliver.c:199
*7  0x58fa0664 in up_schedule_sigaction (tcb=0xf4e20f40, sigdeliver=0x58f1bab5 <nxsig_deliver>) at sim/sim_schedulesigaction.c:88
*8  0x58f19907 in nxsig_queue_action (stcb=0xf4e20f40, info=0xf4049304) at signal/sig_dispatch.c:115
*9  0x58f1b089 in nxsig_tcbdispatch (stcb=0xf4e20f40, info=0xf4049304) at signal/sig_dispatch.c:435
*10 0x58f31853 in nxsig_unmask_pendingsignal () at signal/sig_unmaskpendingsignal.c:104
*11 0x58f1ca09 in nxsig_deliver (stcb=0xf4e20f40) at signal/sig_deliver.c:199
*12 0x58fa0664 in up_schedule_sigaction (tcb=0xf4e20f40, sigdeliver=0x58f1bab5 <nxsig_deliver>) at sim/sim_schedulesigaction.c:88
*13 0x58f19907 in nxsig_queue_action (stcb=0xf4e20f40, info=0xf40492d4) at signal/sig_dispatch.c:115
*14 0x58f1b089 in nxsig_tcbdispatch (stcb=0xf4e20f40, info=0xf40492d4) at signal/sig_dispatch.c:435
*15 0x58f31853 in nxsig_unmask_pendingsignal () at signal/sig_unmaskpendingsignal.c:104
*16 0x58f1ca09 in nxsig_deliver (stcb=0xf4e20f40) at signal/sig_deliver.c:199
*17 0x58fa0664 in up_schedule_sigaction (tcb=0xf4e20f40, sigdeliver=0x58f1bab5 <nxsig_deliver>) at sim/sim_schedulesigaction.c:88
*18 0x58f19907 in nxsig_queue_action (stcb=0xf4e20f40, info=0xf40492a4) at signal/sig_dispatch.c:115
*19 0x58f1b089 in nxsig_tcbdispatch (stcb=0xf4e20f40, info=0xf40492a4) at signal/sig_dispatch.c:435
*20 0x58f31853 in nxsig_unmask_pendingsignal () at signal/sig_unmaskpendingsignal.c:104
*21 0x58f1ca09 in nxsig_deliver (stcb=0xf4e20f40) at signal/sig_deliver.c:199
*22 0x58fa0664 in up_schedule_sigaction (tcb=0xf4e20f40, sigdeliver=0x58f1bab5 <nxsig_deliver>) at sim/sim_schedulesigaction.c:88
*23 0x58f19907 in nxsig_queue_action (stcb=0xf4e20f40, info=0xf4049274) at signal/sig_dispatch.c:115
*24 0x58f1b089 in nxsig_tcbdispatch (stcb=0xf4e20f40, info=0xf4049274) at signal/sig_dispatch.c:435
*25 0x58f31853 in nxsig_unmask_pendingsignal () at signal/sig_unmaskpendingsignal.c:104
*26 0x58f1ca09 in nxsig_deliver (stcb=0xf4e20f40) at signal/sig_deliver.c:199
*27 0x58fa0664 in up_schedule_sigaction (tcb=0xf4e20f40, sigdeliver=0x58f1bab5 <nxsig_deliver>) at sim/sim_schedulesigaction.c:88
*28 0x58f19907 in nxsig_queue_action (stcb=0xf4e20f40, info=0xf4049244) at signal/sig_dispatch.c:115
*29 0x58f1b089 in nxsig_tcbdispatch (stcb=0xf4e20f40, info=0xf4049244) at signal/sig_dispatch.c:435
*30 0x58f31853 in nxsig_unmask_pendingsignal () at signal/sig_unmaskpendingsignal.c:104
*31 0x58f1ca09 in nxsig_deliver (stcb=0xf4e20f40) at signal/sig_deliver.c:199

Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
2023-05-17 11:53:18 -06:00

428 lines
15 KiB
C

/****************************************************************************
* arch/arm/src/armv6-m/arm_schedulesigaction.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdint.h>
#include <sched.h>
#include <assert.h>
#include <debug.h>
#include <nuttx/irq.h>
#include <nuttx/arch.h>
#include "psr.h"
#include "exc_return.h"
#include "sched/sched.h"
#include "arm_internal.h"
#include "irq/irq.h"
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: up_schedule_sigaction
*
* Description:
* This function is called by the OS when one or more
* signal handling actions have been queued for execution.
* The architecture specific code must configure things so
* that the 'sigdeliver' callback is executed on the thread
* specified by 'tcb' as soon as possible.
*
* This function may be called from interrupt handling logic.
*
* This operation should not cause the task to be unblocked
* nor should it cause any immediate execution of sigdeliver.
* Typically, a few cases need to be considered:
*
* (1) This function may be called from an interrupt handler
* During interrupt processing, all xcptcontext structures
* should be valid for all tasks. That structure should
* be modified to invoke sigdeliver() either on return
* from (this) interrupt or on some subsequent context
* switch to the recipient task.
* (2) If not in an interrupt handler and the tcb is NOT
* the currently executing task, then again just modify
* the saved xcptcontext structure for the recipient
* task so it will invoke sigdeliver when that task is
* later resumed.
* (3) If not in an interrupt handler and the tcb IS the
* currently executing task -- just call the signal
* handler now.
*
* Assumptions:
* Called from critical section
*
****************************************************************************/
#ifndef CONFIG_SMP
void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
{
sinfo("tcb=%p sigdeliver=%p\n", tcb, sigdeliver);
DEBUGASSERT(tcb != NULL && sigdeliver != NULL);
/* Refuse to handle nested signal actions */
if (tcb->xcp.sigdeliver == NULL)
{
tcb->xcp.sigdeliver = sigdeliver;
/* First, handle some special cases when the signal is being delivered
* to the currently executing task.
*/
sinfo("rtcb=%p CURRENT_REGS=%p\n", this_task(), CURRENT_REGS);
if (tcb == this_task())
{
/* CASE 1: We are not in an interrupt handler and a task is
* signaling itself for some reason.
*/
if (!CURRENT_REGS)
{
/* In this case just deliver the signal now.
* REVISIT: Signal handle will run in a critical section!
*/
sigdeliver(tcb);
tcb->xcp.sigdeliver = NULL;
}
/* CASE 2: We are in an interrupt handler AND the interrupted
* task is the same as the one that must receive the signal, then
* we will have to modify the return state as well as the state in
* the TCB.
*/
else
{
/* Save the return PC, CPSR and PRIMASK
* registers (and perhaps also the LR). These will be
* restored by the signal trampoline after the signal has been
* delivered.
*/
/* And make sure that the saved context in the TCB is the same
* as the interrupt return context.
*/
arm_savestate(tcb->xcp.saved_regs);
/* Duplicate the register context. These will be
* restored by the signal trampoline after the signal has been
* delivered.
*/
CURRENT_REGS = (void *)
((uint32_t)CURRENT_REGS -
XCPTCONTEXT_SIZE);
memcpy((uint32_t *)CURRENT_REGS, tcb->xcp.saved_regs,
XCPTCONTEXT_SIZE);
CURRENT_REGS[REG_SP] = (uint32_t)CURRENT_REGS +
XCPTCONTEXT_SIZE;
/* Then set up to vector to the trampoline with interrupts
* disabled. The kernel-space trampoline must run in
* privileged thread mode.
*/
CURRENT_REGS[REG_PC] = (uint32_t)arm_sigdeliver;
CURRENT_REGS[REG_PRIMASK] = 1;
CURRENT_REGS[REG_XPSR] = ARMV6M_XPSR_T;
#ifdef CONFIG_BUILD_PROTECTED
CURRENT_REGS[REG_LR] = EXC_RETURN_PRIVTHR;
CURRENT_REGS[REG_EXC_RETURN] = EXC_RETURN_PRIVTHR;
#endif
}
}
/* Otherwise, we are (1) signaling a task is not running from an
* interrupt handler or (2) we are not in an interrupt handler and the
* running task is signaling* some non-running task.
*/
else
{
/* Save the return PC, CPSR and PRIMASK
* registers (and perhaps also the LR). These will be restored
* by the signal trampoline after the signal has been delivered.
*/
/* Save the current register context location */
tcb->xcp.saved_regs = tcb->xcp.regs;
/* Duplicate the register context. These will be
* restored by the signal trampoline after the signal has been
* delivered.
*/
tcb->xcp.regs = (void *)
((uint32_t)tcb->xcp.regs -
XCPTCONTEXT_SIZE);
memcpy(tcb->xcp.regs, tcb->xcp.saved_regs, XCPTCONTEXT_SIZE);
tcb->xcp.regs[REG_SP] = (uint32_t)tcb->xcp.regs +
XCPTCONTEXT_SIZE;
/* Then set up to vector to the trampoline with interrupts
* disabled. We must already be in privileged thread mode to be
* here.
*/
tcb->xcp.regs[REG_PC] = (uint32_t)arm_sigdeliver;
tcb->xcp.regs[REG_PRIMASK] = 1;
tcb->xcp.regs[REG_XPSR] = ARMV6M_XPSR_T;
#ifdef CONFIG_BUILD_PROTECTED
tcb->xcp.regs[REG_LR] = EXC_RETURN_PRIVTHR;
#endif
}
}
}
#endif /* !CONFIG_SMP */
#ifdef CONFIG_SMP
void up_schedule_sigaction(struct tcb_s *tcb, sig_deliver_t sigdeliver)
{
int cpu;
int me;
sinfo("tcb=%p sigdeliver=%p\n", tcb, sigdeliver);
/* Refuse to handle nested signal actions */
if (!tcb->xcp.sigdeliver)
{
tcb->xcp.sigdeliver = sigdeliver;
/* First, handle some special cases when the signal is being delivered
* to task that is currently executing on any CPU.
*/
sinfo("rtcb=%p CURRENT_REGS=%p\n", this_task(), CURRENT_REGS);
if (tcb->task_state == TSTATE_TASK_RUNNING)
{
me = this_cpu();
cpu = tcb->cpu;
/* CASE 1: We are not in an interrupt handler and a task is
* signaling itself for some reason.
*/
if (cpu == me && !CURRENT_REGS)
{
/* In this case just deliver the signal now.
* REVISIT: Signal handler will run in a critical section!
*/
sigdeliver(tcb);
tcb->xcp.sigdeliver = NULL;
}
/* CASE 2: The task that needs to receive the signal is running.
* This could happen if the task is running on another CPU OR if
* we are in an interrupt handler and the task is running on this
* CPU. In the former case, we will have to PAUSE the other CPU
* first. But in either case, we will have to modify the return
* state as well as the state in the TCB.
*/
else
{
/* If we signaling a task running on the other CPU, we have
* to PAUSE the other CPU.
*/
if (cpu != me)
{
/* Pause the CPU */
up_cpu_pause(cpu);
/* Wait while the pause request is pending */
while (up_cpu_pausereq(cpu))
{
}
/* Now tcb on the other CPU can be accessed safely */
/* Copy tcb->xcp.regs to tcp.xcp.saved. These will be
* restored by the signal trampoline after the signal has
* been delivered.
*/
/* Save the current register context location */
tcb->xcp.saved_regs = tcb->xcp.regs;
/* Duplicate the register context. These will be
* restored by the signal trampoline after the signal has
* been delivered.
*/
tcb->xcp.regs = (void *)
((uint32_t)tcb->xcp.regs -
XCPTCONTEXT_SIZE);
memcpy(tcb->xcp.regs, tcb->xcp.saved_regs,
XCPTCONTEXT_SIZE);
tcb->xcp.regs[REG_SP] = (uint32_t)tcb->xcp.regs +
XCPTCONTEXT_SIZE;
/* Then set up vector to the trampoline with interrupts
* disabled. We must already be in privileged thread mode
* to be here.
*/
tcb->xcp.regs[REG_PC] = (uint32_t)arm_sigdeliver;
tcb->xcp.regs[REG_PRIMASK] = 1;
tcb->xcp.regs[REG_XPSR] = ARMV6M_XPSR_T;
#ifdef CONFIG_BUILD_PROTECTED
tcb->xcp.regs[REG_LR] = EXC_RETURN_PRIVTHR;
#endif
}
else
{
/* tcb is running on the same CPU */
/* Save the return PC, CPSR and either the BASEPRI or
* PRIMASK registers (and perhaps also the LR). These
* will be restored by the signal trampoline after the
* signal has been delivered.
*/
/* And make sure that the saved context in the TCB is the
* same as the interrupt return context.
*/
arm_savestate(tcb->xcp.saved_regs);
/* Duplicate the register context. These will be
* restored by the signal trampoline after the signal has
* been delivered.
*/
CURRENT_REGS = (void *)
((uint32_t)CURRENT_REGS -
XCPTCONTEXT_SIZE);
memcpy((uint32_t *)CURRENT_REGS, tcb->xcp.saved_regs,
XCPTCONTEXT_SIZE);
CURRENT_REGS[REG_SP] = (uint32_t)CURRENT_REGS +
XCPTCONTEXT_SIZE;
/* Then set up vector to the trampoline with interrupts
* disabled. The kernel-space trampoline must run in
* privileged thread mode.
*/
CURRENT_REGS[REG_PC] = (uint32_t)arm_sigdeliver;
CURRENT_REGS[REG_PRIMASK] = 1;
CURRENT_REGS[REG_XPSR] = ARMV6M_XPSR_T;
#ifdef CONFIG_BUILD_PROTECTED
CURRENT_REGS[REG_LR] = EXC_RETURN_PRIVTHR;
#endif
}
/* Increment the IRQ lock count so that when the task is
* restarted, it will hold the IRQ spinlock.
*/
DEBUGASSERT(tcb->irqcount < INT16_MAX);
tcb->irqcount++;
/* NOTE: If the task runs on another CPU(cpu), adjusting
* global IRQ controls will be done in the pause handler
* on the CPU(cpu) by taking a critical section.
* If the task is scheduled on this CPU(me), do nothing
* because this CPU already took a critical section
*/
/* RESUME the other CPU if it was PAUSED */
if (cpu != me)
{
up_cpu_resume(cpu);
}
}
}
/* Otherwise, we are (1) signaling a task is not running from an
* interrupt handler or (2) we are not in an interrupt handler and the
* running task is signaling some other non-running task.
*/
else
{
/* Save the return PC, CPSR and either the BASEPRI or PRIMASK
* registers (and perhaps also the LR). These will be restored
* by the signal trampoline after the signal has been delivered.
*/
/* Save the current register context location */
tcb->xcp.saved_regs = tcb->xcp.regs;
/* Duplicate the register context. These will be
* restored by the signal trampoline after the signal has been
* delivered.
*/
tcb->xcp.regs = (void *)
((uint32_t)tcb->xcp.regs -
XCPTCONTEXT_SIZE);
memcpy(tcb->xcp.regs, tcb->xcp.saved_regs, XCPTCONTEXT_SIZE);
tcb->xcp.regs[REG_SP] = (uint32_t)tcb->xcp.regs +
XCPTCONTEXT_SIZE;
/* Increment the IRQ lock count so that when the task is restarted,
* it will hold the IRQ spinlock.
*/
DEBUGASSERT(tcb->irqcount < INT16_MAX);
tcb->irqcount++;
/* Then set up to vector to the trampoline with interrupts
* disabled. We must already be in privileged thread mode to be
* here.
*/
tcb->xcp.regs[REG_PC] = (uint32_t)arm_sigdeliver;
tcb->xcp.regs[REG_PRIMASK] = 1;
tcb->xcp.regs[REG_XPSR] = ARMV6M_XPSR_T;
#ifdef CONFIG_BUILD_PROTECTED
tcb->xcp.regs[REG_LR] = EXC_RETURN_PRIVTHR;
#endif
}
}
}
#endif /* CONFIG_SMP */