| Message ID | 1472025499-6758-1-git-send-email-shawn.lin@rock-chips.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 24 August 2016 at 09:58, Shawn Lin <shawn.lin@rock-chips.com> wrote: > packed should always exist without calling its cleanup function > explicitly. Moreover, we have use it when preparing packed list. > So I don't believe we should ever fall into this check again when > doing mmc_blk_packed_hdr_wrq_prep or mmc_blk_end_packed_req. And > the code of mmc_blk_end_packed_req is trying to use packed before > checking it which makes it quite weird. This patch is trying to > remove these two checks and move it to the mmc_blk_prep_packed_list. > If we find packed is null, then we should never use MMC_PACKED_NONE > and MMC_BLK_PACKED_CMD. By doing this, we could fall back to > non-packed request if finding null packed, though it's impossible > theoretically. > > Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> > > --- > > Changes in v2: > - remove BUG_ON and add fallback for packed instead of > panic it. > > drivers/mmc/card/block.c | 16 ++++++++++++---- > 1 file changed, 12 insertions(+), 4 deletions(-) > > diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c > index 48a5dd7..c7a9b28 100644 > --- a/drivers/mmc/card/block.c > +++ b/drivers/mmc/card/block.c > @@ -1673,6 +1673,18 @@ static u8 mmc_blk_prep_packed_list(struct mmc_queue *mq, struct request *req) > u8 max_packed_rw = 0; > u8 reqs = 0; > > + /* > + * We don't need to check packed for any further > + * operation of packed stuff as we set MMC_PACKED_NONE > + * and return zero for reqs if geting null packed. Also > + * we clean the flag of MMC_BLK_PACKED_CMD to avoid doing > + * it again when removing blk req. > + */ > + if (!mqrq->packed) { > + md->flags &= (~MMC_BLK_PACKED_CMD); > + goto no_packed; > + } > + > if (!(md->flags & MMC_BLK_PACKED_CMD)) > goto no_packed; > > @@ -1781,8 +1793,6 @@ static void mmc_blk_packed_hdr_wrq_prep(struct mmc_queue_req *mqrq, > u8 hdr_blocks; > u8 i = 1; > > - BUG_ON(!packed); > - > mqrq->cmd_type = MMC_PACKED_WRITE; > packed->blocks = 0; > packed->idx_failure = MMC_PACKED_NR_IDX; > @@ -1886,8 +1896,6 @@ static int mmc_blk_end_packed_req(struct mmc_queue_req *mq_rq) > int idx = packed->idx_failure, i = 0; > int ret = 0; > > - BUG_ON(!packed); > - > while (!list_empty(&packed->list)) { > prq = list_entry_rq(packed->list.next); > if (idx == i) { > -- > 2.3.7 > > This is step in the right direction, although there are still some BUG_ONs() for the packed command path. Could you please have look and remove all of them? Kind regards Uffe -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
在 2016/8/24 17:30, Ulf Hansson 写道: > On 24 August 2016 at 09:58, Shawn Lin <shawn.lin@rock-chips.com> wrote: >> packed should always exist without calling its cleanup function >> explicitly. Moreover, we have use it when preparing packed list. >> So I don't believe we should ever fall into this check again when >> doing mmc_blk_packed_hdr_wrq_prep or mmc_blk_end_packed_req. And >> the code of mmc_blk_end_packed_req is trying to use packed before >> checking it which makes it quite weird. This patch is trying to >> remove these two checks and move it to the mmc_blk_prep_packed_list. >> If we find packed is null, then we should never use MMC_PACKED_NONE >> and MMC_BLK_PACKED_CMD. By doing this, we could fall back to >> non-packed request if finding null packed, though it's impossible >> theoretically. >> >> Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> >> >> --- >> >> Changes in v2: >> - remove BUG_ON and add fallback for packed instead of >> panic it. >> >> drivers/mmc/card/block.c | 16 ++++++++++++---- >> 1 file changed, 12 insertions(+), 4 deletions(-) >> >> diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c >> index 48a5dd7..c7a9b28 100644 >> --- a/drivers/mmc/card/block.c >> +++ b/drivers/mmc/card/block.c >> @@ -1673,6 +1673,18 @@ static u8 mmc_blk_prep_packed_list(struct mmc_queue *mq, struct request *req) >> u8 max_packed_rw = 0; >> u8 reqs = 0; >> >> + /* >> + * We don't need to check packed for any further >> + * operation of packed stuff as we set MMC_PACKED_NONE >> + * and return zero for reqs if geting null packed. Also >> + * we clean the flag of MMC_BLK_PACKED_CMD to avoid doing >> + * it again when removing blk req. >> + */ >> + if (!mqrq->packed) { >> + md->flags &= (~MMC_BLK_PACKED_CMD); >> + goto no_packed; >> + } >> + >> if (!(md->flags & MMC_BLK_PACKED_CMD)) >> goto no_packed; >> >> @@ -1781,8 +1793,6 @@ static void mmc_blk_packed_hdr_wrq_prep(struct mmc_queue_req *mqrq, >> u8 hdr_blocks; >> u8 i = 1; >> >> - BUG_ON(!packed); >> - >> mqrq->cmd_type = MMC_PACKED_WRITE; >> packed->blocks = 0; >> packed->idx_failure = MMC_PACKED_NR_IDX; >> @@ -1886,8 +1896,6 @@ static int mmc_blk_end_packed_req(struct mmc_queue_req *mq_rq) >> int idx = packed->idx_failure, i = 0; >> int ret = 0; >> >> - BUG_ON(!packed); >> - >> while (!list_empty(&packed->list)) { >> prq = list_entry_rq(packed->list.next); >> if (idx == i) { >> -- >> 2.3.7 >> >> > > This is step in the right direction, although there are still some > BUG_ONs() for the packed command path. Could you please have look and > remove all of them? yup, I will try to remove all of them when I respin v3. Thansk. > > Kind regards > Uffe > > >
diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c index 48a5dd7..c7a9b28 100644 --- a/drivers/mmc/card/block.c +++ b/drivers/mmc/card/block.c @@ -1673,6 +1673,18 @@ static u8 mmc_blk_prep_packed_list(struct mmc_queue *mq, struct request *req) u8 max_packed_rw = 0; u8 reqs = 0; + /* + * We don't need to check packed for any further + * operation of packed stuff as we set MMC_PACKED_NONE + * and return zero for reqs if geting null packed. Also + * we clean the flag of MMC_BLK_PACKED_CMD to avoid doing + * it again when removing blk req. + */ + if (!mqrq->packed) { + md->flags &= (~MMC_BLK_PACKED_CMD); + goto no_packed; + } + if (!(md->flags & MMC_BLK_PACKED_CMD)) goto no_packed; @@ -1781,8 +1793,6 @@ static void mmc_blk_packed_hdr_wrq_prep(struct mmc_queue_req *mqrq, u8 hdr_blocks; u8 i = 1; - BUG_ON(!packed); - mqrq->cmd_type = MMC_PACKED_WRITE; packed->blocks = 0; packed->idx_failure = MMC_PACKED_NR_IDX; @@ -1886,8 +1896,6 @@ static int mmc_blk_end_packed_req(struct mmc_queue_req *mq_rq) int idx = packed->idx_failure, i = 0; int ret = 0; - BUG_ON(!packed); - while (!list_empty(&packed->list)) { prq = list_entry_rq(packed->list.next); if (idx == i) {
packed should always exist without calling its cleanup function explicitly. Moreover, we have use it when preparing packed list. So I don't believe we should ever fall into this check again when doing mmc_blk_packed_hdr_wrq_prep or mmc_blk_end_packed_req. And the code of mmc_blk_end_packed_req is trying to use packed before checking it which makes it quite weird. This patch is trying to remove these two checks and move it to the mmc_blk_prep_packed_list. If we find packed is null, then we should never use MMC_PACKED_NONE and MMC_BLK_PACKED_CMD. By doing this, we could fall back to non-packed request if finding null packed, though it's impossible theoretically. Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> --- Changes in v2: - remove BUG_ON and add fallback for packed instead of panic it. drivers/mmc/card/block.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-)