On 2018/5/23 4:21, Jason Gunthorpe wrote: > On Sat, May 19, 2018 at 04:24:40PM +0800, Wei Hu (Xavier) wrote: >> >> On 2018/5/17 23:00, Jason Gunthorpe wrote: >>> On Thu, May 17, 2018 at 04:02:49PM +0800, Wei Hu (Xavier) wrote: >>>> This patch Implements the IB core disassociate_ucontext API. >>>> >>>> Signed-off-by: Wei Hu (Xavier) <xavier.huwei@xxxxxxxxxx> >>>> drivers/infiniband/hw/hns/hns_roce_main.c | 36 +++++++++++++++++++++++++++++++ >>>> 1 file changed, 36 insertions(+) >>>> >>>> diff --git a/drivers/infiniband/hw/hns/hns_roce_main.c b/drivers/infiniband/hw/hns/hns_roce_main.c >>>> index 96fb6a9..7fafe9d 100644 >>>> +++ b/drivers/infiniband/hw/hns/hns_roce_main.c >>>> @@ -33,6 +33,9 @@ >>>> #include <linux/acpi.h> >>>> #include <linux/of_platform.h> >>>> #include <linux/module.h> >>>> +#include <linux/sched.h> >>>> +#include <linux/sched/mm.h> >>>> +#include <linux/sched/task.h> >>>> #include <rdma/ib_addr.h> >>>> #include <rdma/ib_smi.h> >>>> #include <rdma/ib_user_verbs.h> >>>> @@ -422,6 +425,38 @@ static int hns_roce_port_immutable(struct ib_device *ib_dev, u8 port_num, >>>> return 0; >>>> } >>>> >>>> +static void hns_roce_disassociate_ucontext(struct ib_ucontext *ibcontext) >>>> +{ >>>> + struct task_struct *process; >>>> + struct mm_struct *mm; >>>> + >>>> + process = get_pid_task(ibcontext->tgid, PIDTYPE_PID); >>>> + if (!process) >>>> + return; >>>> + >>>> + mm = get_task_mm(process); >>>> + if (!mm) { >>>> + pr_info("no mm, disassociate ucontext is pending task termination\n"); >>>> + while (1) { >>>> + put_task_struct(process); >>>> + usleep_range(1000, 2000); >>>> + process = get_pid_task(ibcontext->tgid, PIDTYPE_PID); >>>> + if (!process || process->state == TASK_DEAD) { >>>> + pr_info("disassociate ucontext done, task was terminated\n"); >>>> + /* if task was dead, need to release the task >>>> + * struct. >>>> + */ >>>> + if (process) >>>> + put_task_struct(process); >>>> + return; >>>> + } >>>> + } >>>> + } >>> I don't want to see this boilerplate code copied into every >>> driver. Hoist it into the core code, have the disassociate driver callback >>> accept a mm_struct parameter, and refactor the other drivers using this. >> When the userspace RDMA application process is suspended for some reason >> without executing ibv_close_device function, >> There will be calltrace as follows when rmmod roce kernel driver ko in >> the current version. >> It looks like a common problem to every driver and the code segment >> above is suitable for every driver. >> Pardon me for asking, but if you have any plan to do this? > My plan is to ask you to do it :) Hi, Jason I will pull this patch out of the series and send V2. We will think how to hoist it into the core code later. Thanks Regards Wei Hu > Jason > > . > -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html