* [dpdk-dev] [PATCH] lib/librte_timer:fix corruption with reset
@ 2020-07-07 9:03 Sarosh Arif
2020-07-07 16:09 ` Stephen Hemminger
` (2 more replies)
0 siblings, 3 replies; 10+ messages in thread
From: Sarosh Arif @ 2020-07-07 9:03 UTC (permalink / raw)
To: rsanford, erik.g.carrillo, dev; +Cc: stable, Sarosh Arif, h.mikita89
If the user tries to reset/stop some other timer in it's callback
function, which is also about to expire, using
rte_timer_reset_sync/rte_timer_stop_sync the application goes into
an infinite loop. This happens because
rte_timer_reset_sync/rte_timer_stop_sync loop until the timer
resets/stops and there is check inside timer_set_config_state which
prevents a running timer from being reset/stopped by not it's own
timer_cb. Therefore timer_set_config_state returns -1 due to which
rte_timer_reset returns -1 and rte_timer_reset_sync goes into an
infinite loop.
The soloution to this problem is to return -1 from
rte_timer_reset_sync/rte_timer_stop_sync in case the user tries to
reset/stop some other timer in it's callback function.
Bugzilla ID: 491
Fixes: 20d159f20543 ("timer: fix corruption with reset")
Cc: h.mikita89@gmail.com
Signed-off-by: Sarosh Arif <sarosh.arif@emumba.com>
---
lib/librte_timer/rte_timer.c | 25 +++++++++++++++++++++++--
lib/librte_timer/rte_timer.h | 4 ++--
2 files changed, 25 insertions(+), 4 deletions(-)
diff --git a/lib/librte_timer/rte_timer.c b/lib/librte_timer/rte_timer.c
index 6d19ce469..ed48bcbfd 100644
--- a/lib/librte_timer/rte_timer.c
+++ b/lib/librte_timer/rte_timer.c
@@ -576,14 +576,24 @@ rte_timer_alt_reset(uint32_t timer_data_id, struct rte_timer *tim,
}
/* loop until rte_timer_reset() succeed */
-void
+int
rte_timer_reset_sync(struct rte_timer *tim, uint64_t ticks,
enum rte_timer_type type, unsigned tim_lcore,
rte_timer_cb_t fct, void *arg)
{
+ struct rte_timer_data *timer_data;
+ TIMER_DATA_VALID_GET_OR_ERR_RET(default_data_id, timer_data, -EINVAL);
+
+ if (tim->status.state == RTE_TIMER_RUNNING && \
+ (tim->status.owner != (uint16_t)tim_lcore || \
+ tim != timer_data->priv_timer[tim_lcore].running_tim))
+ return -1;
+
while (rte_timer_reset(tim, ticks, type, tim_lcore,
fct, arg) != 0)
rte_pause();
+
+ return 0;
}
static int
@@ -642,11 +652,22 @@ rte_timer_alt_stop(uint32_t timer_data_id, struct rte_timer *tim)
}
/* loop until rte_timer_stop() succeed */
-void
+int
rte_timer_stop_sync(struct rte_timer *tim)
{
+ struct rte_timer_data *timer_data;
+ TIMER_DATA_VALID_GET_OR_ERR_RET(default_data_id, timer_data, -EINVAL);
+ unsigned int lcore_id = rte_lcore_id();
+
+ if (tim->status.state == RTE_TIMER_RUNNING && \
+ (tim->status.owner != (uint16_t)lcore_id || \
+ tim != timer_data->priv_timer[lcore_id].running_tim))
+ return -1;
+
while (rte_timer_stop(tim) != 0)
rte_pause();
+
+ return 0;
}
/* Test the PENDING status of the timer handle tim */
diff --git a/lib/librte_timer/rte_timer.h b/lib/librte_timer/rte_timer.h
index c6b3d450d..392ca423d 100644
--- a/lib/librte_timer/rte_timer.h
+++ b/lib/librte_timer/rte_timer.h
@@ -275,7 +275,7 @@ int rte_timer_reset(struct rte_timer *tim, uint64_t ticks,
* @param arg
* The user argument of the callback function.
*/
-void
+int
rte_timer_reset_sync(struct rte_timer *tim, uint64_t ticks,
enum rte_timer_type type, unsigned tim_lcore,
rte_timer_cb_t fct, void *arg);
@@ -314,7 +314,7 @@ int rte_timer_stop(struct rte_timer *tim);
* @param tim
* The timer handle.
*/
-void rte_timer_stop_sync(struct rte_timer *tim);
+int rte_timer_stop_sync(struct rte_timer *tim);
/**
* Test if a timer is pending.
--
2.17.1
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [dpdk-dev] [PATCH] lib/librte_timer:fix corruption with reset
2020-07-07 9:03 [dpdk-dev] [PATCH] lib/librte_timer:fix corruption with reset Sarosh Arif
@ 2020-07-07 16:09 ` Stephen Hemminger
2020-07-08 5:06 ` [dpdk-dev] [PATCH v2] " Sarosh Arif
2020-07-10 6:59 ` [dpdk-dev] [PATCH v3] " Sarosh Arif
2 siblings, 0 replies; 10+ messages in thread
From: Stephen Hemminger @ 2020-07-07 16:09 UTC (permalink / raw)
To: Sarosh Arif; +Cc: rsanford, erik.g.carrillo, dev, stable, h.mikita89
On Tue, 7 Jul 2020 14:03:20 +0500
Sarosh Arif <sarosh.arif@emumba.com> wrote:
> + struct rte_timer_data *timer_data;
> + TIMER_DATA_VALID_GET_OR_ERR_RET(default_data_id, timer_data, -EINVAL);
> +
> + if (tim->status.state == RTE_TIMER_RUNNING && \
> + (tim->status.owner != (uint16_t)tim_lcore || \
> + tim != timer_data->priv_timer[tim_lcore].running_tim))
> + return -1;
> +
This is code not a macro.
Look at checkpatch output, no \ in code.
^ permalink raw reply [flat|nested] 10+ messages in thread
* [dpdk-dev] [PATCH v2] lib/librte_timer:fix corruption with reset
2020-07-07 9:03 [dpdk-dev] [PATCH] lib/librte_timer:fix corruption with reset Sarosh Arif
2020-07-07 16:09 ` Stephen Hemminger
@ 2020-07-08 5:06 ` Sarosh Arif
2020-07-08 15:07 ` Stephen Hemminger
2020-07-08 15:08 ` Stephen Hemminger
2020-07-10 6:59 ` [dpdk-dev] [PATCH v3] " Sarosh Arif
2 siblings, 2 replies; 10+ messages in thread
From: Sarosh Arif @ 2020-07-08 5:06 UTC (permalink / raw)
To: rsanford, erik.g.carrillo, dev; +Cc: stable, Sarosh Arif, h.mikita89
If the user tries to reset/stop some other timer in it's callback
function, which is also about to expire, using
rte_timer_reset_sync/rte_timer_stop_sync the application goes into
an infinite loop. This happens because
rte_timer_reset_sync/rte_timer_stop_sync loop until the timer
resets/stops and there is check inside timer_set_config_state which
prevents a running timer from being reset/stopped by not it's own
timer_cb. Therefore timer_set_config_state returns -1 due to which
rte_timer_reset returns -1 and rte_timer_reset_sync goes into an
infinite loop.
The soloution to this problem is to return -1 from
rte_timer_reset_sync/rte_timer_stop_sync in case the user tries to
reset/stop some other timer in it's callback function.
Bugzilla ID: 491
Fixes: 20d159f20543 ("timer: fix corruption with reset")
Cc: h.mikita89@gmail.com
Signed-off-by: Sarosh Arif <sarosh.arif@emumba.com>
---
v2: remove line continuations
---
lib/librte_timer/rte_timer.c | 25 +++++++++++++++++++++++--
lib/librte_timer/rte_timer.h | 4 ++--
2 files changed, 25 insertions(+), 4 deletions(-)
diff --git a/lib/librte_timer/rte_timer.c b/lib/librte_timer/rte_timer.c
index 6d19ce469..be86385a1 100644
--- a/lib/librte_timer/rte_timer.c
+++ b/lib/librte_timer/rte_timer.c
@@ -576,14 +576,24 @@ rte_timer_alt_reset(uint32_t timer_data_id, struct rte_timer *tim,
}
/* loop until rte_timer_reset() succeed */
-void
+int
rte_timer_reset_sync(struct rte_timer *tim, uint64_t ticks,
enum rte_timer_type type, unsigned tim_lcore,
rte_timer_cb_t fct, void *arg)
{
+ struct rte_timer_data *timer_data;
+ TIMER_DATA_VALID_GET_OR_ERR_RET(default_data_id, timer_data, -EINVAL);
+
+ if (tim->status.state == RTE_TIMER_RUNNING &&
+ (tim->status.owner != (uint16_t)tim_lcore ||
+ tim != timer_data->priv_timer[tim_lcore].running_tim))
+ return -1;
+
while (rte_timer_reset(tim, ticks, type, tim_lcore,
fct, arg) != 0)
rte_pause();
+
+ return 0;
}
static int
@@ -642,11 +652,22 @@ rte_timer_alt_stop(uint32_t timer_data_id, struct rte_timer *tim)
}
/* loop until rte_timer_stop() succeed */
-void
+int
rte_timer_stop_sync(struct rte_timer *tim)
{
+ struct rte_timer_data *timer_data;
+ TIMER_DATA_VALID_GET_OR_ERR_RET(default_data_id, timer_data, -EINVAL);
+ unsigned int lcore_id = rte_lcore_id();
+
+ if (tim->status.state == RTE_TIMER_RUNNING &&
+ (tim->status.owner != (uint16_t)lcore_id ||
+ tim != timer_data->priv_timer[lcore_id].running_tim))
+ return -1;
+
while (rte_timer_stop(tim) != 0)
rte_pause();
+
+ return 0;
}
/* Test the PENDING status of the timer handle tim */
diff --git a/lib/librte_timer/rte_timer.h b/lib/librte_timer/rte_timer.h
index c6b3d450d..392ca423d 100644
--- a/lib/librte_timer/rte_timer.h
+++ b/lib/librte_timer/rte_timer.h
@@ -275,7 +275,7 @@ int rte_timer_reset(struct rte_timer *tim, uint64_t ticks,
* @param arg
* The user argument of the callback function.
*/
-void
+int
rte_timer_reset_sync(struct rte_timer *tim, uint64_t ticks,
enum rte_timer_type type, unsigned tim_lcore,
rte_timer_cb_t fct, void *arg);
@@ -314,7 +314,7 @@ int rte_timer_stop(struct rte_timer *tim);
* @param tim
* The timer handle.
*/
-void rte_timer_stop_sync(struct rte_timer *tim);
+int rte_timer_stop_sync(struct rte_timer *tim);
/**
* Test if a timer is pending.
--
2.17.1
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [dpdk-dev] [PATCH v2] lib/librte_timer:fix corruption with reset
2020-07-08 5:06 ` [dpdk-dev] [PATCH v2] " Sarosh Arif
@ 2020-07-08 15:07 ` Stephen Hemminger
2020-07-09 7:05 ` Sarosh Arif
2020-07-08 15:08 ` Stephen Hemminger
1 sibling, 1 reply; 10+ messages in thread
From: Stephen Hemminger @ 2020-07-08 15:07 UTC (permalink / raw)
To: Sarosh Arif; +Cc: rsanford, erik.g.carrillo, dev, stable, h.mikita89
On Wed, 8 Jul 2020 10:06:26 +0500
Sarosh Arif <sarosh.arif@emumba.com> wrote:
> /* loop until rte_timer_reset() succeed */
> -void
> +int
> rte_timer_reset_sync(struct rte_timer *tim, uint64_t ticks,
> enum rte_timer_type type, unsigned tim_lcore,
> rte_timer_cb_t fct, void *arg)
This is an API change and needs to wait until a breaking release like 20.11.
Also most applications won't test the result.
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [dpdk-dev] [PATCH v2] lib/librte_timer:fix corruption with reset
2020-07-08 5:06 ` [dpdk-dev] [PATCH v2] " Sarosh Arif
2020-07-08 15:07 ` Stephen Hemminger
@ 2020-07-08 15:08 ` Stephen Hemminger
2020-07-09 7:02 ` Sarosh Arif
1 sibling, 1 reply; 10+ messages in thread
From: Stephen Hemminger @ 2020-07-08 15:08 UTC (permalink / raw)
To: Sarosh Arif; +Cc: rsanford, erik.g.carrillo, dev, stable, h.mikita89
On Wed, 8 Jul 2020 10:06:26 +0500
Sarosh Arif <sarosh.arif@emumba.com> wrote:
> rte_timer_stop_sync(struct rte_timer *tim)
> {
> + struct rte_timer_data *timer_data;
> + TIMER_DATA_VALID_GET_OR_ERR_RET(default_data_id, timer_data, -EINVAL);
> + unsigned int lcore_id = rte_lcore_id();
This mixing code and declarations. since the macro has a return statement.
Maybe:
struct rte_timer_data *timer_data;
unsigned int lcore_id = rte_lcore_id();
TIMER_DATA_VALID_GET_OR_ERR_RET(default_data_id, timer_data, -EINVAL);
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [dpdk-dev] [PATCH v2] lib/librte_timer:fix corruption with reset
2020-07-08 15:08 ` Stephen Hemminger
@ 2020-07-09 7:02 ` Sarosh Arif
0 siblings, 0 replies; 10+ messages in thread
From: Sarosh Arif @ 2020-07-09 7:02 UTC (permalink / raw)
To: Stephen Hemminger; +Cc: rsanford, erik.g.carrillo, dev, stable, h.mikita89
On Wed, Jul 8, 2020 at 8:08 PM Stephen Hemminger <stephen@networkplumber.org>
wrote:
> On Wed, 8 Jul 2020 10:06:26 +0500
> Sarosh Arif <sarosh.arif@emumba.com> wrote:
>
> > rte_timer_stop_sync(struct rte_timer *tim)
> > {
> > + struct rte_timer_data *timer_data;
> > + TIMER_DATA_VALID_GET_OR_ERR_RET(default_data_id, timer_data,
> -EINVAL);
> > + unsigned int lcore_id = rte_lcore_id();
>
> This mixing code and declarations. since the macro has a return statement.
>
> Maybe:
>
> struct rte_timer_data *timer_data;
> unsigned int lcore_id = rte_lcore_id();
>
> TIMER_DATA_VALID_GET_OR_ERR_RET(default_data_id, timer_data,
> -EINVAL);
>
I will fix this in the next version.
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [dpdk-dev] [PATCH v2] lib/librte_timer:fix corruption with reset
2020-07-08 15:07 ` Stephen Hemminger
@ 2020-07-09 7:05 ` Sarosh Arif
0 siblings, 0 replies; 10+ messages in thread
From: Sarosh Arif @ 2020-07-09 7:05 UTC (permalink / raw)
To: Stephen Hemminger; +Cc: rsanford, erik.g.carrillo, dev, stable, h.mikita89
On Wed, Jul 8, 2020 at 8:07 PM Stephen Hemminger <stephen@networkplumber.org>
wrote:
> On Wed, 8 Jul 2020 10:06:26 +0500
> Sarosh Arif <sarosh.arif@emumba.com> wrote:
>
> > /* loop until rte_timer_reset() succeed */
> > -void
> > +int
> > rte_timer_reset_sync(struct rte_timer *tim, uint64_t ticks,
> > enum rte_timer_type type, unsigned tim_lcore,
> > rte_timer_cb_t fct, void *arg)
>
> This is an API change and needs to wait until a breaking release like
> 20.11.
>
Okay,waiting till the next breaking release sounds fine to me.
> Also most applications won't test the result.
>
^ permalink raw reply [flat|nested] 10+ messages in thread
* [dpdk-dev] [PATCH v3] lib/librte_timer:fix corruption with reset
2020-07-07 9:03 [dpdk-dev] [PATCH] lib/librte_timer:fix corruption with reset Sarosh Arif
2020-07-07 16:09 ` Stephen Hemminger
2020-07-08 5:06 ` [dpdk-dev] [PATCH v2] " Sarosh Arif
@ 2020-07-10 6:59 ` Sarosh Arif
2020-07-10 15:19 ` Stephen Hemminger
2020-07-28 19:04 ` Carrillo, Erik G
2 siblings, 2 replies; 10+ messages in thread
From: Sarosh Arif @ 2020-07-10 6:59 UTC (permalink / raw)
To: rsanford, erik.g.carrillo, dev; +Cc: stable, Sarosh Arif, h.mikita89
If the user tries to reset/stop some other timer in it's callback
function, which is also about to expire, using
rte_timer_reset_sync/rte_timer_stop_sync the application goes into
an infinite loop. This happens because
rte_timer_reset_sync/rte_timer_stop_sync loop until the timer
resets/stops and there is check inside timer_set_config_state which
prevents a running timer from being reset/stopped by not it's own
timer_cb. Therefore timer_set_config_state returns -1 due to which
rte_timer_reset returns -1 and rte_timer_reset_sync goes into an
infinite loop.
The soloution to this problem is to return -1 from
rte_timer_reset_sync/rte_timer_stop_sync in case the user tries to
reset/stop some other timer in it's callback function.
Bugzilla ID: 491
Fixes: 20d159f20543 ("timer: fix corruption with reset")
Cc: h.mikita89@gmail.com
Signed-off-by: Sarosh Arif <sarosh.arif@emumba.com>
---
v2: remove line continuations
v3: separate code and declarations
---
lib/librte_timer/rte_timer.c | 26 ++++++++++++++++++++++++--
lib/librte_timer/rte_timer.h | 4 ++--
2 files changed, 26 insertions(+), 4 deletions(-)
diff --git a/lib/librte_timer/rte_timer.c b/lib/librte_timer/rte_timer.c
index 6d19ce469..0cd3e2c86 100644
--- a/lib/librte_timer/rte_timer.c
+++ b/lib/librte_timer/rte_timer.c
@@ -576,14 +576,24 @@ rte_timer_alt_reset(uint32_t timer_data_id, struct rte_timer *tim,
}
/* loop until rte_timer_reset() succeed */
-void
+int
rte_timer_reset_sync(struct rte_timer *tim, uint64_t ticks,
enum rte_timer_type type, unsigned tim_lcore,
rte_timer_cb_t fct, void *arg)
{
+ struct rte_timer_data *timer_data;
+ TIMER_DATA_VALID_GET_OR_ERR_RET(default_data_id, timer_data, -EINVAL);
+
+ if (tim->status.state == RTE_TIMER_RUNNING &&
+ (tim->status.owner != (uint16_t)tim_lcore ||
+ tim != timer_data->priv_timer[tim_lcore].running_tim))
+ return -1;
+
while (rte_timer_reset(tim, ticks, type, tim_lcore,
fct, arg) != 0)
rte_pause();
+
+ return 0;
}
static int
@@ -642,11 +652,23 @@ rte_timer_alt_stop(uint32_t timer_data_id, struct rte_timer *tim)
}
/* loop until rte_timer_stop() succeed */
-void
+int
rte_timer_stop_sync(struct rte_timer *tim)
{
+ struct rte_timer_data *timer_data;
+ unsigned int lcore_id = rte_lcore_id();
+
+ TIMER_DATA_VALID_GET_OR_ERR_RET(default_data_id, timer_data, -EINVAL);
+
+ if (tim->status.state == RTE_TIMER_RUNNING &&
+ (tim->status.owner != (uint16_t)lcore_id ||
+ tim != timer_data->priv_timer[lcore_id].running_tim))
+ return -1;
+
while (rte_timer_stop(tim) != 0)
rte_pause();
+
+ return 0;
}
/* Test the PENDING status of the timer handle tim */
diff --git a/lib/librte_timer/rte_timer.h b/lib/librte_timer/rte_timer.h
index c6b3d450d..392ca423d 100644
--- a/lib/librte_timer/rte_timer.h
+++ b/lib/librte_timer/rte_timer.h
@@ -275,7 +275,7 @@ int rte_timer_reset(struct rte_timer *tim, uint64_t ticks,
* @param arg
* The user argument of the callback function.
*/
-void
+int
rte_timer_reset_sync(struct rte_timer *tim, uint64_t ticks,
enum rte_timer_type type, unsigned tim_lcore,
rte_timer_cb_t fct, void *arg);
@@ -314,7 +314,7 @@ int rte_timer_stop(struct rte_timer *tim);
* @param tim
* The timer handle.
*/
-void rte_timer_stop_sync(struct rte_timer *tim);
+int rte_timer_stop_sync(struct rte_timer *tim);
/**
* Test if a timer is pending.
--
2.17.1
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [dpdk-dev] [PATCH v3] lib/librte_timer:fix corruption with reset
2020-07-10 6:59 ` [dpdk-dev] [PATCH v3] " Sarosh Arif
@ 2020-07-10 15:19 ` Stephen Hemminger
2020-07-28 19:04 ` Carrillo, Erik G
1 sibling, 0 replies; 10+ messages in thread
From: Stephen Hemminger @ 2020-07-10 15:19 UTC (permalink / raw)
To: Sarosh Arif; +Cc: rsanford, erik.g.carrillo, dev, stable, h.mikita89
On Fri, 10 Jul 2020 11:59:54 +0500
Sarosh Arif <sarosh.arif@emumba.com> wrote:
> If the user tries to reset/stop some other timer in it's callback
> function, which is also about to expire, using
> rte_timer_reset_sync/rte_timer_stop_sync the application goes into
> an infinite loop. This happens because
> rte_timer_reset_sync/rte_timer_stop_sync loop until the timer
> resets/stops and there is check inside timer_set_config_state which
> prevents a running timer from being reset/stopped by not it's own
> timer_cb. Therefore timer_set_config_state returns -1 due to which
> rte_timer_reset returns -1 and rte_timer_reset_sync goes into an
> infinite loop.
>
> The soloution to this problem is to return -1 from
> rte_timer_reset_sync/rte_timer_stop_sync in case the user tries to
> reset/stop some other timer in it's callback function.
>
> Bugzilla ID: 491
> Fixes: 20d159f20543 ("timer: fix corruption with reset")
> Cc: h.mikita89@gmail.com
> Signed-off-by: Sarosh Arif <sarosh.arif@emumba.com>
> ---
> v2: remove line continuations
> v3: separate code and declarations
If you want to change the return value, you need to go through the steps
in the API/ABI policy. Maybe even symbol versioning.
Sorry, I know it is painful but we committed to the rules.
And changing the return value can never go to stable.
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [dpdk-dev] [PATCH v3] lib/librte_timer:fix corruption with reset
2020-07-10 6:59 ` [dpdk-dev] [PATCH v3] " Sarosh Arif
2020-07-10 15:19 ` Stephen Hemminger
@ 2020-07-28 19:04 ` Carrillo, Erik G
1 sibling, 0 replies; 10+ messages in thread
From: Carrillo, Erik G @ 2020-07-28 19:04 UTC (permalink / raw)
To: Sarosh Arif, dev, rsanford; +Cc: h.mikita89, Stephen Hemminger
Hi Sarosh,
Some comments in-line:
> -----Original Message-----
> From: Sarosh Arif <sarosh.arif@emumba.com>
> Sent: Friday, July 10, 2020 2:00 AM
> To: rsanford@akamai.com; Carrillo, Erik G <erik.g.carrillo@intel.com>;
> dev@dpdk.org
> Cc: stable@dpdk.org; Sarosh Arif <sarosh.arif@emumba.com>;
> h.mikita89@gmail.com
> Subject: [PATCH v3] lib/librte_timer:fix corruption with reset
The subject is misleading - perhaps wording closer to the title of the Bugzilla bug would be more helpful.
>
> If the user tries to reset/stop some other timer in it's callback function, which
> is also about to expire, using rte_timer_reset_sync/rte_timer_stop_sync the
> application goes into an infinite loop. This happens because
> rte_timer_reset_sync/rte_timer_stop_sync loop until the timer resets/stops
> and there is check inside timer_set_config_state which prevents a running
> timer from being reset/stopped by not it's own timer_cb. Therefore
> timer_set_config_state returns -1 due to which rte_timer_reset returns -1
> and rte_timer_reset_sync goes into an infinite loop.
>
> The soloution to this problem is to return -1 from
> rte_timer_reset_sync/rte_timer_stop_sync in case the user tries to
> reset/stop some other timer in it's callback function.
>
> Bugzilla ID: 491
> Fixes: 20d159f20543 ("timer: fix corruption with reset")
> Cc: h.mikita89@gmail.com
> Signed-off-by: Sarosh Arif <sarosh.arif@emumba.com>
> ---
> v2: remove line continuations
> v3: separate code and declarations
> ---
> lib/librte_timer/rte_timer.c | 26 ++++++++++++++++++++++++--
> lib/librte_timer/rte_timer.h | 4 ++--
> 2 files changed, 26 insertions(+), 4 deletions(-)
>
> diff --git a/lib/librte_timer/rte_timer.c b/lib/librte_timer/rte_timer.c index
> 6d19ce469..0cd3e2c86 100644
> --- a/lib/librte_timer/rte_timer.c
> +++ b/lib/librte_timer/rte_timer.c
> @@ -576,14 +576,24 @@ rte_timer_alt_reset(uint32_t timer_data_id, struct
> rte_timer *tim, }
>
> /* loop until rte_timer_reset() succeed */ -void
> +int
> rte_timer_reset_sync(struct rte_timer *tim, uint64_t ticks,
> enum rte_timer_type type, unsigned tim_lcore,
> rte_timer_cb_t fct, void *arg)
> {
> + struct rte_timer_data *timer_data;
> + TIMER_DATA_VALID_GET_OR_ERR_RET(default_data_id,
> timer_data, -EINVAL);
> +
> + if (tim->status.state == RTE_TIMER_RUNNING &&
> + (tim->status.owner != (uint16_t)tim_lcore ||
> + tim != timer_data->priv_timer[tim_lcore].running_tim))
> + return -1;
> +
As I understand it, Bugzilla 491 describes two scenarios where a hang can occur:
1. A timer's callback tries to synchronously reset/stop another timer in the same run list
2. A timer's callback tries to synchronously reset/stop another timer in a different run list whose lcore happens to be running a timer callback that is synchronously resetting/stopping a timer in the first run list
The if condition from the patch above can be broken up as:
(tim->status.state == RTE_TIMER_RUNNING && tim->status.owner == (uint16_t)lcore_id && tim != timer_data->priv_timer[lcore_id].running_tim)
And
(tim->status.state == RTE_TIMER_RUNNING && tim->status.owner != (uint16_t)lcore_id)
This second condition could be transient and doesn't necessarily identify scenario (2) above. In this case, the *_sync() calls could fail unnecessarily.
Offhand, I'm not seeing a way to more precisely detect scenario 2 above. I'm wondering if some kind of a timeout parameter could be added to avoid hanging instead. Thoughts?
As Stephen mentioned in another response, it looks like this will require an API change. I believe this can be announced in the next release via doc/guides/rel_notes/deprecation.rst. Then, the new API can be added in the next ABI-breaking release, possibly with versioned symbols (http://doc.dpdk.org/guides/contributing/abi_versioning.html#versioning-macros).
Thanks,
Erik
> while (rte_timer_reset(tim, ticks, type, tim_lcore,
> fct, arg) != 0)
> rte_pause();
> +
> + return 0;
> }
>
> static int
> @@ -642,11 +652,23 @@ rte_timer_alt_stop(uint32_t timer_data_id, struct
> rte_timer *tim) }
>
> /* loop until rte_timer_stop() succeed */ -void
> +int
> rte_timer_stop_sync(struct rte_timer *tim) {
> + struct rte_timer_data *timer_data;
> + unsigned int lcore_id = rte_lcore_id();
> +
> + TIMER_DATA_VALID_GET_OR_ERR_RET(default_data_id,
> timer_data, -EINVAL);
> +
> + if (tim->status.state == RTE_TIMER_RUNNING &&
> + (tim->status.owner != (uint16_t)lcore_id ||
> + tim != timer_data->priv_timer[lcore_id].running_tim))
> + return -1;
> +
> while (rte_timer_stop(tim) != 0)
> rte_pause();
> +
> + return 0;
> }
>
> /* Test the PENDING status of the timer handle tim */ diff --git
> a/lib/librte_timer/rte_timer.h b/lib/librte_timer/rte_timer.h index
> c6b3d450d..392ca423d 100644
> --- a/lib/librte_timer/rte_timer.h
> +++ b/lib/librte_timer/rte_timer.h
> @@ -275,7 +275,7 @@ int rte_timer_reset(struct rte_timer *tim, uint64_t
> ticks,
> * @param arg
> * The user argument of the callback function.
> */
> -void
> +int
> rte_timer_reset_sync(struct rte_timer *tim, uint64_t ticks,
> enum rte_timer_type type, unsigned tim_lcore,
> rte_timer_cb_t fct, void *arg);
> @@ -314,7 +314,7 @@ int rte_timer_stop(struct rte_timer *tim);
> * @param tim
> * The timer handle.
> */
> -void rte_timer_stop_sync(struct rte_timer *tim);
> +int rte_timer_stop_sync(struct rte_timer *tim);
>
> /**
> * Test if a timer is pending.
> --
> 2.17.1
^ permalink raw reply [flat|nested] 10+ messages in thread
end of thread, other threads:[~2020-07-28 19:04 UTC | newest]
Thread overview: 10+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-07-07 9:03 [dpdk-dev] [PATCH] lib/librte_timer:fix corruption with reset Sarosh Arif
2020-07-07 16:09 ` Stephen Hemminger
2020-07-08 5:06 ` [dpdk-dev] [PATCH v2] " Sarosh Arif
2020-07-08 15:07 ` Stephen Hemminger
2020-07-09 7:05 ` Sarosh Arif
2020-07-08 15:08 ` Stephen Hemminger
2020-07-09 7:02 ` Sarosh Arif
2020-07-10 6:59 ` [dpdk-dev] [PATCH v3] " Sarosh Arif
2020-07-10 15:19 ` Stephen Hemminger
2020-07-28 19:04 ` Carrillo, Erik G
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