lkml.org 
[lkml]   [2020]   [Nov]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    Date
    SubjectRe: [PATCH 2/3] venus: Limit HFI sessions to the maximum supported
    On Thu, Nov 19, 2020 at 4:12 PM Stanimir Varbanov
    <stanimir.varbanov@linaro.org> wrote:
    >
    > Currently we rely on firmware to return error when we reach the maximum
    > supported number of sessions. But this errors are happened at reqbuf
    > time which is a bit later. The more reasonable way looks like is to
    > return the error on driver open.
    >
    > To achieve that modify hfi_session_create to return error when we reach
    > maximum count of sessions and thus refuse open.
    >
    > Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
    > ---
    > drivers/media/platform/qcom/venus/core.h | 1 +
    > drivers/media/platform/qcom/venus/hfi.c | 19 +++++++++++++++----
    > .../media/platform/qcom/venus/hfi_parser.c | 3 +++
    > 3 files changed, 19 insertions(+), 4 deletions(-)
    >
    > diff --git a/drivers/media/platform/qcom/venus/core.h b/drivers/media/platform/qcom/venus/core.h
    > index db0e6738281e..3a477fcdd3a8 100644
    > --- a/drivers/media/platform/qcom/venus/core.h
    > +++ b/drivers/media/platform/qcom/venus/core.h
    > @@ -96,6 +96,7 @@ struct venus_format {
    > #define MAX_CAP_ENTRIES 32
    > #define MAX_ALLOC_MODE_ENTRIES 16
    > #define MAX_CODEC_NUM 32
    > +#define MAX_SESSIONS 16
    >
    > struct raw_formats {
    > u32 buftype;
    > diff --git a/drivers/media/platform/qcom/venus/hfi.c b/drivers/media/platform/qcom/venus/hfi.c
    > index 638ed5cfe05e..8420be6d3991 100644
    > --- a/drivers/media/platform/qcom/venus/hfi.c
    > +++ b/drivers/media/platform/qcom/venus/hfi.c
    > @@ -175,6 +175,7 @@ static int wait_session_msg(struct venus_inst *inst)
    > int hfi_session_create(struct venus_inst *inst, const struct hfi_inst_ops *ops)
    > {
    > struct venus_core *core = inst->core;
    > + int ret;
    >
    > if (!ops)
    > return -EINVAL;
    > @@ -183,12 +184,22 @@ int hfi_session_create(struct venus_inst *inst, const struct hfi_inst_ops *ops)
    > init_completion(&inst->done);
    > inst->ops = ops;
    >
    > - mutex_lock(&core->lock);
    > - list_add_tail(&inst->list, &core->instances);
    > - atomic_inc(&core->insts_count);
    > + ret = mutex_lock_interruptible(&core->lock);
    > + if (ret)
    > + return ret;
    > +
    > + ret = atomic_read(&core->insts_count);
    > + if (ret + 1 > core->max_sessions_supported) {
    > + ret = -EAGAIN;
    > + } else {
    > + atomic_inc(&core->insts_count);
    > + list_add_tail(&inst->list, &core->instances);
    > + ret = 0;
    > + }
    > +
    > mutex_unlock(&core->lock);
    >
    > - return 0;
    > + return ret;
    > }
    > EXPORT_SYMBOL_GPL(hfi_session_create);
    >
    > diff --git a/drivers/media/platform/qcom/venus/hfi_parser.c b/drivers/media/platform/qcom/venus/hfi_parser.c
    > index 363ee2a65453..52898633a8e6 100644
    > --- a/drivers/media/platform/qcom/venus/hfi_parser.c
    > +++ b/drivers/media/platform/qcom/venus/hfi_parser.c
    > @@ -276,6 +276,9 @@ u32 hfi_parser(struct venus_core *core, struct venus_inst *inst, void *buf,
    > words_count--;
    > }
    >

    My understanding of the hardware is that there is a max number of
    macroblocks that can be worked on at a time. That works out to
    nominally 16 clips. But large clips can take more resources. Does
    |max_sessions_supported| get updated with the amount that system can
    use? Or is it always a constant?

    If it changes depending on system load, then couldn't
    |core->max_sessions_supported| be 0 if all of the resources have been
    used up? If that is the case then the below check would appear to be
    incorrect.

    > + if (!core->max_sessions_supported)
    > + core->max_sessions_supported = MAX_SESSIONS;
    > +
    > parser_fini(inst, codecs, domain);
    >
    > return HFI_ERR_NONE;
    > --
    > 2.17.1
    >

    \
     
     \ /
      Last update: 2020-11-21 02:16    [W:4.640 / U:0.324 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site