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Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Haren Myneni , Rick Lindsley , Nick Child , Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , "Christophe Leroy (CS GROUP)" , linuxppc-dev@lists.ozlabs.org References: <20261012095452.135828-1-marco.crivellari@suse.com> <20261012095452.135828-2-marco.crivellari@suse.com> Content-Language: en-US From: mingming cao In-Reply-To: <20261012095452.135828-2-marco.crivellari@suse.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-Reinject: loops=2 maxloops=12 X-Proofpoint-GUID: LGXgFU0TpwWO4Rmjiw6wRlCKA4EQoH_L X-Proofpoint-ORIG-GUID: TjZICohO1dTAQx0xDC9FPrm7GTarATKr X-Authority-Analysis: v=2.4 cv=aqInmiZV c=1 sm=1 tr=0 ts=6ad294f9 cx=c_pps a=AfN7/Ok6k8XGzOShvHwTGQ==:117 a=AfN7/Ok6k8XGzOShvHwTGQ==:17 a=IkcTkHD0fZMA:10 a=660iZSQnnn4A:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=U7nrCbtTmkRpXpFmAIza:22 a=VnNF1IyMAAAA:8 a=pGLkceISAAAA:8 a=VwQbUJbxAAAA:8 a=voM4FWlXAAAA:8 a=iox4zFpeAAAA:8 a=tkcf6-MeEqR6izG4hBoA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 a=O8hF6Hzn-FEA:10 a=IC2XNlieTeVoXbcui8wp:22 a=WzC6qhA0u3u7Ye7llzcV:22 X-Proofpoint-Spam-Info: AW1haW4tMjYxMDE2MDA4NCBTYWx0ZWRfX0bt0ILkmD9/o jTvfNCQLa1mQGB/qU9SmRmSyCy5cu6kye+YCQsWqwlXlzFl5nj/HnIpudSINruK9rVsCdUTSVvy /I0QQ5fxZglk3YjzxiKRNLMgy/Yczb8= X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYxMDE2MDA4NCBTYWx0ZWRfXxB+JlbBJyzI3 Acx+6yxotE9DfpYHkf7VC14+iL7TU8Hkt15f+nOtqxnd7LARup7oYoSbbqmTh+mD+yqBolAZafH yldDBD2tWVkwoWks82qds8rjeJJ9Xtxklko5ODfDfdWcc2BN0gmcE6v/MZKAThuQXlYRBm7p/K9 bKhLIuUtrfOP/V0bGnxH/NHPuUBCYPDh+DHAvTKzzk3tEFxWD0cYFjGIIFWEKhERFSsZtIMzPfj 3l4voCqS1xDaESbmSKwkAMQZ7rnEcIYo15yhsMnGDF282GmxBFeYuKBh9N+vyRQbv2CIxpOXoFj Z2atUTKMJhOZILSlv0SJQWakYrfyA53cy5MZf2s796AnetRBgL/qgra21Y0d28kxzekHwfaHt7v XNqjgbdwOFMczd8sWJ5K684vumk87mkCXJV8uA4MYdRCMGyzBQG/+mYbZzzTUploGq3z0gqTIZx 8kdTtEk5emp9CPiF64w== X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1176,Hydra:6.1.134,FMLib:17.12.100.49 definitions=2026-10-16_03,2026-10-14_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 phishscore=0 clxscore=1011 spamscore=0 malwarescore=0 suspectscore=0 bulkscore=0 adultscore=0 impostorscore=0 priorityscore=1501 lowpriorityscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2610080000 definitions=main-2610160084 On 10/12/26 2:54 AM, Marco Crivellari 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 > Cc: Rick Lindsley > Cc: Nick Child > Cc: Madhavan Srinivasan > Cc: Michael Ellerman > Cc: Nicholas Piggin > Cc: Christophe Leroy (CS GROUP) > Cc: linuxppc-dev@lists.ozlabs.org > Signed-off-by: Marco Crivellari > --- > drivers/net/ethernet/ibm/ibmvnic.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c > index 5a510eed335e..d4c284c8ef43 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 { > @@ -3454,7 +3454,7 @@ static int ibmvnic_reset(struct ibmvnic_adapter *adapter, > list_add_tail(&rwi->list, &adapter->rwi_list); > netdev_dbg(adapter->netdev, "Scheduling reset (reason %s)\n", > reset_reason_to_string(reason)); > - queue_work(system_long_wq, &adapter->ibmvnic_reset); > + queue_work(system_dfl_long_wq, &adapter->ibmvnic_reset); > > ret = 0; > err: On 10/12/26 2:54 AM, Marco Crivellari 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 > Cc: Rick Lindsley > Cc: Nick Child > Cc: Madhavan Srinivasan > Cc: Michael Ellerman > Cc: Nicholas Piggin > Cc: Christophe Leroy (CS GROUP) > Cc: linuxppc-dev@lists.ozlabs.org > Signed-off-by: Marco Crivellari > --- > drivers/net/ethernet/ibm/ibmvnic.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c > index 5a510eed335e..d4c284c8ef43 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 { > @@ -3454,7 +3454,7 @@ static int ibmvnic_reset(struct ibmvnic_adapter *adapter, > list_add_tail(&rwi->list, &adapter->rwi_list); > netdev_dbg(adapter->netdev, "Scheduling reset (reason %s)\n", > reset_reason_to_string(reason)); > - queue_work(system_long_wq, &adapter->ibmvnic_reset); > + queue_work(system_dfl_long_wq, &adapter->ibmvnic_reset); > > ret = 0; > err: I walked through the reset path and the conversion looks fine. All three system_long_wq users move together and there are no remaining users in the driver. The work items don't rely on per-CPU state, so system_dfl_long_wq seems appropriate here. Minor commit message nit: ibmvnic doesn't use mod_delayed_work(), and one of the conversions is queue_work() rather than delayed work. Acked-by: Mingming Cao