net: Add control functions for irq suspension

The napi_suspend_irqs routine bootstraps irq suspension by elongating
the defer timeout to irq_suspend_timeout.

The napi_resume_irqs routine effectively cancels irq suspension by
forcing the napi to be scheduled immediately.

Signed-off-by: Martin Karsten <mkarsten@uwaterloo.ca>
Co-developed-by: Joe Damato <jdamato@fastly.com>
Signed-off-by: Joe Damato <jdamato@fastly.com>
Tested-by: Joe Damato <jdamato@fastly.com>
Tested-by: Martin Karsten <mkarsten@uwaterloo.ca>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
Link: https://patch.msgid.link/20241109050245.191288-3-jdamato@fastly.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Martin Karsten 2024-11-09 05:02:32 +00:00 committed by Jakub Kicinski
parent 5dc51ec86d
commit 3fcbecbdeb
2 changed files with 40 additions and 0 deletions

View File

@ -52,6 +52,9 @@ void napi_busy_loop_rcu(unsigned int napi_id,
bool (*loop_end)(void *, unsigned long),
void *loop_end_arg, bool prefer_busy_poll, u16 budget);
void napi_suspend_irqs(unsigned int napi_id);
void napi_resume_irqs(unsigned int napi_id);
#else /* CONFIG_NET_RX_BUSY_POLL */
static inline unsigned long net_busy_loop_on(void)
{

View File

@ -6507,6 +6507,43 @@ void napi_busy_loop(unsigned int napi_id,
}
EXPORT_SYMBOL(napi_busy_loop);
void napi_suspend_irqs(unsigned int napi_id)
{
struct napi_struct *napi;
rcu_read_lock();
napi = napi_by_id(napi_id);
if (napi) {
unsigned long timeout = napi_get_irq_suspend_timeout(napi);
if (timeout)
hrtimer_start(&napi->timer, ns_to_ktime(timeout),
HRTIMER_MODE_REL_PINNED);
}
rcu_read_unlock();
}
void napi_resume_irqs(unsigned int napi_id)
{
struct napi_struct *napi;
rcu_read_lock();
napi = napi_by_id(napi_id);
if (napi) {
/* If irq_suspend_timeout is set to 0 between the call to
* napi_suspend_irqs and now, the original value still
* determines the safety timeout as intended and napi_watchdog
* will resume irq processing.
*/
if (napi_get_irq_suspend_timeout(napi)) {
local_bh_disable();
napi_schedule(napi);
local_bh_enable();
}
}
rcu_read_unlock();
}
#endif /* CONFIG_NET_RX_BUSY_POLL */
static void __napi_hash_add_with_id(struct napi_struct *napi,