From 5a80d4e1a34c94204a0bb01443bf25a4fdb12750 Mon Sep 17 00:00:00 2001 From: Guangyao Ma Date: Thu, 26 Aug 2021 15:16:32 +0800 Subject: [PATCH] fix: solve SIGCHLD ignored in sigsuspend() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 在如下场景signal可能得不到及时处理： 1、进程A设置信号a阻塞 2、进程A收到信号a 3、进程A调用sigsuspend结束阻塞 原则上，步骤三应该立刻处理之前被阻塞的信号a，调用信号处理函数，并且sigsuspend 返回。现在的问题是，信号a没有得到及时处理，并且进程A阻塞在sigsuspend()调用流程 。 本次修改，在1、2、3场景下，sigsuspend()处理过程中，如果发现已经收到信号，待处理 时，会立刻进行调度切换，再次调度回来时，在调度模块中，会先主动处理已经收到的信 号，最后sigsuspend返回用户态。 close #I47CKK Signed-off-by: Guangyao Ma Change-Id: I1b30a938a2d18c3f58989d40eee0503ceffb27b5 --- kernel/base/ipc/los_signal.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/kernel/base/ipc/los_signal.c b/kernel/base/ipc/los_signal.c index 06fee687..2c7f72e6 100644 --- a/kernel/base/ipc/los_signal.c +++ b/kernel/base/ipc/los_signal.c @@ -562,9 +562,21 @@ int OsSigSuspend(const sigset_t *set) /* If pending mask not in sigmask, need set sigflag */ OsSigMaskSwitch(rtcb, *set); - ret = OsSigTimedWaitNoLock(&setSuspend, NULL, LOS_WAIT_FOREVER); - if (ret < 0) { - PRINT_ERR("FUNC %s LINE = %d, ret = %x\n", __FUNCTION__, __LINE__, ret); + + if (rtcb->sig.sigFlag > 0) { + SCHEDULER_UNLOCK(intSave); + + /* + * If rtcb->sig.sigFlag > 0, it means that some signal have been + * received, and we need to do schedule to handle the signal directly. + */ + LOS_Schedule(); + return -EINTR; + } else { + ret = OsSigTimedWaitNoLock(&setSuspend, NULL, LOS_WAIT_FOREVER); + if (ret < 0) { + PRINT_ERR("FUNC %s LINE = %d, ret = %x\n", __FUNCTION__, __LINE__, ret); + } } SCHEDULER_UNLOCK(intSave); -- GitLab