[PATCH libnvme v2 0/2] Do not pass disable_sqflow if not supported

[PATCH libnvme v2 0/2] Do not pass disable_sqflow if not supported

[Daniel Wagner]

Follow up on the discussion in [1]

[1] https://lore.kernel.org/linux-nvme/676b7c2b-7bcf-6138-0229-389ed9efaa92@grimberg.me/

Sagi Grimberg (2):
  fabrics: Read the supported options lazy
  fabrics: Do not pass disable_sqflow if not supported

 src/nvme/fabrics.c | 22 ++++++++++++++--------
 1 file changed, 14 insertions(+), 8 deletions(-)

-- 
2.41.0

[PATCH libnvme v2 1/2] fabrics: Read the supported options lazy

[Daniel Wagner]

From: Sagi Grimberg <sagi@grimberg.me>

Read the options in when we need the for the first time.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Daniel Wagner <dwagner@suse.de>
---
 src/nvme/fabrics.c | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/src/nvme/fabrics.c b/src/nvme/fabrics.c
index 800293e2a8e7..9725eeb3cda8 100644
--- a/src/nvme/fabrics.c
+++ b/src/nvme/fabrics.c
@@ -357,10 +357,18 @@ static int __add_argument(char **argstr, const char *tok, const char *arg)
 	return 0;
 }
 
+static int __nvmf_supported_options(nvme_root_t r);
+#define nvmf_check_option(r, tok)					\
+({									\
+	if (!(r)->options)						\
+		__nvmf_supported_options(r);				\
+	(r)->options->tok;						\
+})
+
 #define add_bool_argument(o, argstr, tok, arg)				\
 ({									\
 	int ret;							\
-	if (r->options->tok) {						\
+	if (nvmf_check_option(r, tok)) {				\
 		ret = __add_bool_argument(argstr,			\
 					  stringify(tok),		\
 					  arg);				\
@@ -376,7 +384,7 @@ static int __add_argument(char **argstr, const char *tok, const char *arg)
 #define add_int_argument(o, argstr, tok, arg, allow_zero) \
 ({									\
 	int ret;							\
-	if (r->options->tok) {						\
+	if (nvmf_check_option(r, tok)) {				\
 		ret = __add_int_argument(argstr,			\
 					stringify(tok),			\
 					arg,				\
@@ -393,7 +401,7 @@ static int __add_argument(char **argstr, const char *tok, const char *arg)
 #define add_int_or_minus_one_argument(o, argstr, tok, arg)		\
 ({									\
 	int ret;							\
-	if (r->options->tok) {						\
+	if (nvmf_check_option(r, tok)) {				\
 		ret = __add_int_or_minus_one_argument(argstr,		\
 						     stringify(tok),	\
 						     arg);		\
@@ -409,7 +417,7 @@ static int __add_argument(char **argstr, const char *tok, const char *arg)
 #define add_argument(r, argstr, tok, arg)				\
 ({									\
 	int ret;							\
-	if (r->options->tok) {						\
+	if (nvmf_check_option(r, tok)) {				\
 		ret = __add_argument(argstr,				\
 				     stringify(tok),			\
 				     arg);				\
@@ -913,9 +921,6 @@ int nvmf_add_ctrl(nvme_host_t h, nvme_ctrl_t c,
 		free(traddr);
 	}
 
-	ret = __nvmf_supported_options(h->r);
-	if (ret)
-		return ret;
 	ret = build_options(h, c, &argstr);
 	if (ret)
 		return ret;
-- 
2.41.0

[PATCH libnvme v2 2/2] fabrics: Do not pass disable_sqflow if not supported

[Daniel Wagner]

From: Sagi Grimberg <sagi@grimberg.me>

Only retry a connect attempt with disable_sqflow if the kernel
actually supports this option.

Reported-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Daniel Wagner <dwagner@suse.de>
---
 src/nvme/fabrics.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/nvme/fabrics.c b/src/nvme/fabrics.c
index 9725eeb3cda8..f0e85d3b766d 100644
--- a/src/nvme/fabrics.c
+++ b/src/nvme/fabrics.c
@@ -1043,7 +1043,8 @@ nvme_ctrl_t nvmf_connect_disc_entry(nvme_host_t h,
 	if (!ret)
 		return c;
 
-	if (errno == EINVAL && c->cfg.disable_sqflow) {
+	if (errno == EINVAL && c->cfg.disable_sqflow &&
+	    nvmf_check_option(h->r, disable_sqflow)) {
 		errno = 0;
 		/* disable_sqflow is unrecognized option on older kernels */
 		nvme_msg(h->r, LOG_INFO, "failed to connect controller, "
-- 
2.41.0

Re: [PATCH libnvme v2 2/2] fabrics: Do not pass disable_sqflow if not supported

[Sagi Grimberg]

> Only retry a connect attempt with disable_sqflow if the kernel
> actually supports this option.
> 
> Reported-by: Sagi Grimberg <sagi@grimberg.me>
> Signed-off-by: Daniel Wagner <dwagner@suse.de>
> ---
>   src/nvme/fabrics.c | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/src/nvme/fabrics.c b/src/nvme/fabrics.c
> index 9725eeb3cda8..f0e85d3b766d 100644
> --- a/src/nvme/fabrics.c
> +++ b/src/nvme/fabrics.c
> @@ -1043,7 +1043,8 @@ nvme_ctrl_t nvmf_connect_disc_entry(nvme_host_t h,
>   	if (!ret)
>   		return c;
>   
> -	if (errno == EINVAL && c->cfg.disable_sqflow) {
> +	if (errno == EINVAL && c->cfg.disable_sqflow &&
> +	    nvmf_check_option(h->r, disable_sqflow)) {
>   		errno = 0;
>   		/* disable_sqflow is unrecognized option on older kernels */
>   		nvme_msg(h->r, LOG_INFO, "failed to connect controller, "

I think you want to check this before the initial call
and avoid the retry altogether.
--
-       if (e->treq & NVMF_TREQ_DISABLE_SQFLOW)
+       if (e->treq & NVMF_TREQ_DISABLE_SQFLOW &&
+           nvmf_check_option(h->r, disable_sqflow))
                 c->cfg.disable_sqflow = true;
+       else
+               c->cfg.disable_sqflow = false;

         if (e->trtype == NVMF_TRTYPE_TCP &&
             (e->treq & NVMF_TREQ_REQUIRED ||
--

Re: [PATCH libnvme v2 2/2] fabrics: Do not pass disable_sqflow if not supported

[Daniel Wagner]

On Tue, Aug 08, 2023 at 11:47:14AM +0300, Sagi Grimberg wrote:
> I think you want to check this before the initial call
> and avoid the retry altogether.
> --
> -       if (e->treq & NVMF_TREQ_DISABLE_SQFLOW)
> +       if (e->treq & NVMF_TREQ_DISABLE_SQFLOW &&
> +           nvmf_check_option(h->r, disable_sqflow))
>                 c->cfg.disable_sqflow = true;
> +       else
> +               c->cfg.disable_sqflow = false;
> 
>         if (e->trtype == NVMF_TRTYPE_TCP &&
>             (e->treq & NVMF_TREQ_REQUIRED ||

Yep, makes sense.