Re: [PATCH] habanalabs: replace usage of found with dedicated list iterator variable

From: Oded Gabbay
Date: Thu Mar 24 2022 - 10:40:55 EST


On Thu, Mar 24, 2022 at 9:11 AM Jakob Koschel <jakobkoschel@xxxxxxxxx> wrote:
>
> To move the list iterator variable into the list_for_each_entry_*()
> macro in the future it should be avoided to use the list iterator
> variable after the loop body.
>
> To *never* use the list iterator variable after the loop it was
> concluded to use a separate iterator variable instead of a
> found boolean [1].
>
> This removes the need to use a found variable and simply checking if
> the variable was set, can determine if the break/goto was hit.
>
> Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@xxxxxxxxxxxxxx/
> Signed-off-by: Jakob Koschel <jakobkoschel@xxxxxxxxx>
> ---
> drivers/misc/habanalabs/common/command_submission.c | 11 +++++------
> 1 file changed, 5 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/misc/habanalabs/common/command_submission.c b/drivers/misc/habanalabs/common/command_submission.c
> index 0a4ef13d9ac4..4927749e439c 100644
> --- a/drivers/misc/habanalabs/common/command_submission.c
> +++ b/drivers/misc/habanalabs/common/command_submission.c
> @@ -405,8 +405,7 @@ static void staged_cs_put(struct hl_device *hdev, struct hl_cs *cs)
>
> static void cs_handle_tdr(struct hl_device *hdev, struct hl_cs *cs)
> {
> - bool next_entry_found = false;
> - struct hl_cs *next, *first_cs;
> + struct hl_cs *next = NULL, *iter, *first_cs;
>
> if (!cs_needs_timeout(cs))
> return;
> @@ -441,13 +440,13 @@ static void cs_handle_tdr(struct hl_device *hdev, struct hl_cs *cs)
> spin_lock(&hdev->cs_mirror_lock);
>
> /* queue TDR for next CS */
> - list_for_each_entry(next, &hdev->cs_mirror_list, mirror_node)
> - if (cs_needs_timeout(next)) {
> - next_entry_found = true;
> + list_for_each_entry(iter, &hdev->cs_mirror_list, mirror_node)
> + if (cs_needs_timeout(iter)) {
> + next = iter;
> break;
> }
>
> - if (next_entry_found && !next->tdr_active) {
> + if (next && !next->tdr_active) {
> next->tdr_active = true;
> schedule_delayed_work(&next->work_tdr, next->timeout_jiffies);
> }
>
> base-commit: f443e374ae131c168a065ea1748feac6b2e76613
> --
> 2.25.1
>
This patch is
Reviewed-by: Oded Gabbay <ogabbay@xxxxxxxxxx>

Applied to -next.

Thanks,
Oded