[v5,1/1] eal/interrupts: add synchronous wrapper around unregister
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Commit Message
Avoid race with unregister interrupt handler if interrupt
source has some active callbacks at the moment, use wrapper
around rte_intr_callback_unregister() to check for -EAGAIN
return value and to loop until rte_intr_callback_unregister()
succeeds.
Signed-off-by: Renata Saiakhova <Renata.Saiakhova@ekinops.com>
Acked-by: Anatoly Burakov <anatoly.burakov@intel.com>
Acked-by: Harman Kalra <hkalra@marvell.com>
---
drivers/bus/pci/linux/pci_vfio.c | 2 +-
lib/librte_eal/freebsd/eal_interrupts.c | 12 ++++++++++++
lib/librte_eal/include/rte_interrupts.h | 25 +++++++++++++++++++++++++
lib/librte_eal/linux/eal_interrupts.c | 12 ++++++++++++
lib/librte_eal/version.map | 1 +
lib/librte_eal/windows/eal_interrupts.c | 8 ++++++++
6 files changed, 59 insertions(+), 1 deletion(-)
Comments
On Tue, Apr 6, 2021 at 4:50 PM Renata Saiakhova
<Renata.Saiakhova@ekinops.com> wrote:
>
> Avoid race with unregister interrupt handler if interrupt
> source has some active callbacks at the moment, use wrapper
> around rte_intr_callback_unregister() to check for -EAGAIN
> return value and to loop until rte_intr_callback_unregister()
> succeeds.
>
> Signed-off-by: Renata Saiakhova <Renata.Saiakhova@ekinops.com>
> Acked-by: Anatoly Burakov <anatoly.burakov@intel.com>
> Acked-by: Harman Kalra <hkalra@marvell.com>
> ---
[snip]
> diff --git a/lib/librte_eal/version.map b/lib/librte_eal/version.map
> index e23745ae6..88d88aaed 100644
> --- a/lib/librte_eal/version.map
> +++ b/lib/librte_eal/version.map
> @@ -421,6 +421,7 @@ EXPERIMENTAL {
> rte_version_release;
> rte_version_suffix;
> rte_version_year;
> + rte_intr_callback_unregister_sync;
Sorted this alphabetically + added symbol in rte_eal_exports.def.
Applied, thanks.
@@ -409,7 +409,7 @@ pci_vfio_disable_notifier(struct rte_pci_device *dev)
return -1;
}
- ret = rte_intr_callback_unregister(&dev->vfio_req_intr_handle,
+ ret = rte_intr_callback_unregister_sync(&dev->vfio_req_intr_handle,
pci_vfio_req_handler,
(void *)&dev->device);
if (ret < 0) {
@@ -345,6 +345,18 @@ rte_intr_callback_unregister(const struct rte_intr_handle *intr_handle,
return ret;
}
+int
+rte_intr_callback_unregister_sync(const struct rte_intr_handle *intr_handle,
+ rte_intr_callback_fn cb_fn, void *cb_arg)
+{
+ int ret = 0;
+
+ while ((ret = rte_intr_callback_unregister(intr_handle, cb_fn, cb_arg)) == -EAGAIN)
+ rte_pause();
+
+ return ret;
+}
+
int
rte_intr_enable(const struct rte_intr_handle *intr_handle)
{
@@ -94,6 +94,31 @@ rte_intr_callback_unregister_pending(const struct rte_intr_handle *intr_handle,
rte_intr_callback_fn cb_fn, void *cb_arg,
rte_intr_unregister_callback_fn ucb_fn);
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice
+ *
+ * Loop until rte_intr_callback_unregister() succeeds.
+ * After a call to this function,
+ * the callback provided by the specified interrupt handle is unregistered.
+ *
+ * @param intr_handle
+ * pointer to the interrupt handle.
+ * @param cb
+ * callback address.
+ * @param cb_arg
+ * address of parameter for callback, (void *)-1 means to remove all
+ * registered which has the same callback address.
+ *
+ * @return
+ * - On success, return the number of callback entities removed.
+ * - On failure, a negative value.
+ */
+__rte_experimental
+int
+rte_intr_callback_unregister_sync(const struct rte_intr_handle *intr_handle,
+ rte_intr_callback_fn cb, void *cb_arg);
+
/**
* It enables the interrupt for the specified handle.
*
@@ -662,6 +662,18 @@ rte_intr_callback_unregister(const struct rte_intr_handle *intr_handle,
return ret;
}
+int
+rte_intr_callback_unregister_sync(const struct rte_intr_handle *intr_handle,
+ rte_intr_callback_fn cb_fn, void *cb_arg)
+{
+ int ret = 0;
+
+ while ((ret = rte_intr_callback_unregister(intr_handle, cb_fn, cb_arg)) == -EAGAIN)
+ rte_pause();
+
+ return ret;
+}
+
int
rte_intr_enable(const struct rte_intr_handle *intr_handle)
{
@@ -421,6 +421,7 @@ EXPERIMENTAL {
rte_version_release;
rte_version_suffix;
rte_version_year;
+ rte_intr_callback_unregister_sync;
};
INTERNAL {
@@ -131,6 +131,14 @@ rte_intr_callback_unregister(
return 0;
}
+int
+rte_intr_callback_unregister_sync(
+ __rte_unused const struct rte_intr_handle *intr_handle,
+ __rte_unused rte_intr_callback_fn cb_fn, __rte_unused void *cb_arg)
+{
+ return 0;
+}
+
int
rte_intr_enable(__rte_unused const struct rte_intr_handle *intr_handle)
{