| Message ID | 20260511092846.120141-2-marco.crivellari@suse.com (mailing list archive) |
|---|---|
| State | Handled Elsewhere |
| Headers | show |
| Series | [RFC,net-next,1/5] ibmvnic: Move long delayed work on system_dfl_long_wq | expand |
Hi, On Mon, May 11, 2026 at 11:28 AM Marco Crivellari <marco.crivellari@suse.com> wrote: > > Currently the code enqueue work items using {queue|mod}_delayed_work(), > using system_long_wq. This workqueue should be used when long works are > expected and it is a per-cpu workqueue. > > The function(s) end up calling __queue_delayed_work(), which set a global > timer that could fire anywhere, enqueuing the work where the timer fired. > > Unbound works could benefit from scheduler task placement, to optimize > performance and power consumption. Long work shouldn't stick to a single > CPU. > > Recently, a new unbound workqueue specific for long running work has > been added: > > c116737e972e ("workqueue: Add system_dfl_long_wq for long unbound works") > > Since the workqueue work doesn't rely on per-cpu variables, there is no > obvious reason that justify the use of a per-cpu workqueue. So change > system_long_wq with system_dfl_long_wq so that the work may benefit from > scheduler task placement. > > Cc: Haren Myneni <haren@linux.ibm.com> > Cc: Rick Lindsley <ricklind@linux.ibm.com> > Cc: Nick Child <nnac123@linux.ibm.com> > Cc: Madhavan Srinivasan <maddy@linux.ibm.com> > Cc: Michael Ellerman <mpe@ellerman.id.au> > Cc: Nicholas Piggin <npiggin@gmail.com> > Cc: Christophe Leroy (CS GROUP) <chleroy@kernel.org> > Cc: linuxppc-dev@lists.ozlabs.org > Signed-off-by: Marco Crivellari <marco.crivellari@suse.com> > --- > drivers/net/ethernet/ibm/ibmvnic.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) Gentle ping. Thanks!
diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c index 5a510eed335e..a1c01c9820d2 100644 --- a/drivers/net/ethernet/ibm/ibmvnic.c +++ b/drivers/net/ethernet/ibm/ibmvnic.c @@ -3229,7 +3229,7 @@ static void __ibmvnic_reset(struct work_struct *work) if (adapter->state == VNIC_PROBING && !wait_for_completion_timeout(&adapter->probe_done, timeout)) { dev_err(dev, "Reset thread timed out on probe"); - queue_delayed_work(system_long_wq, + queue_delayed_work(system_dfl_long_wq, &adapter->ibmvnic_delayed_reset, IBMVNIC_RESET_DELAY); return; @@ -3267,7 +3267,7 @@ static void __ibmvnic_reset(struct work_struct *work) spin_lock(&adapter->rwi_lock); if (!list_empty(&adapter->rwi_list)) { if (test_and_set_bit_lock(0, &adapter->resetting)) { - queue_delayed_work(system_long_wq, + queue_delayed_work(system_dfl_long_wq, &adapter->ibmvnic_delayed_reset, IBMVNIC_RESET_DELAY); } else {
Currently the code enqueue work items using {queue|mod}_delayed_work(), using system_long_wq. This workqueue should be used when long works are expected and it is a per-cpu workqueue. The function(s) end up calling __queue_delayed_work(), which set a global timer that could fire anywhere, enqueuing the work where the timer fired. Unbound works could benefit from scheduler task placement, to optimize performance and power consumption. Long work shouldn't stick to a single CPU. Recently, a new unbound workqueue specific for long running work has been added: c116737e972e ("workqueue: Add system_dfl_long_wq for long unbound works") Since the workqueue work doesn't rely on per-cpu variables, there is no obvious reason that justify the use of a per-cpu workqueue. So change system_long_wq with system_dfl_long_wq so that the work may benefit from scheduler task placement. Cc: Haren Myneni <haren@linux.ibm.com> Cc: Rick Lindsley <ricklind@linux.ibm.com> Cc: Nick Child <nnac123@linux.ibm.com> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Christophe Leroy (CS GROUP) <chleroy@kernel.org> Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Marco Crivellari <marco.crivellari@suse.com> --- drivers/net/ethernet/ibm/ibmvnic.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)