This code is just ported from the Linux kernel where it is used for around 7 years, so I suppose it is pretty safe. But of course, take your time to test it, I am fine with getting this in the next LTS release.
Igor On Tue, Nov 24, 2020 at 12:43 PM Zhang, Qi Z <qi.z.zh...@intel.com> wrote: > > > > -----Original Message----- > > From: dev <dev-boun...@dpdk.org> On Behalf Of Thomas Monjalon > > Sent: Tuesday, November 24, 2020 4:25 PM > > To: Igor Ryzhov <iryz...@nfware.com>; dev <dev@dpdk.org>; Guo, Jia > > <jia....@intel.com> > > Cc: dpdk stable <sta...@dpdk.org>; Xing, Beilei <beilei.x...@intel.com>; > Yigit, > > Ferruh <ferruh.yi...@intel.com> > > Subject: Re: [dpdk-dev] [PATCH] net/i40e: fix counters > > > > I will follow the recommendation of Ferruh and i40e maintainers. > > It is risky but it can be applied just before the release. > > I will suggest not to merge this patch in this release cycle, we need time > to fully test it and it can always be captured in following LTS release if > no issue be found. > > Thanks > Qi > > > > > > 24/11/2020 04:34, Guo, Jia: > > > hi, igor ryzhov and Thomas > > > > > > Since this remain issue is report recently and we need to reproduce > > > the issue and evaluate the patch and guaranty no side affect for other > case, so > > I am not sure even I don't think it still have time window to hit 20.11. > But > > whatever we have begin to check your patch for now on. What do you think > so? > > > > > > > > > From: Igor Ryzhov <iryz...@nfware.com> > > > Sent: Friday, November 20, 2020 2:27 AM > > > To: dev <dev@dpdk.org> > > > Cc: dpdk stable <sta...@dpdk.org>; Xing, Beilei > > > <beilei.x...@intel.com>; Guo, Jia <jia....@intel.com>; Thomas Monjalon > > > <tho...@monjalon.net> > > > Subject: Re: [PATCH] net/i40e: fix counters > > > > > > CC maintainers and Thomas. > > > > > > This fix should be 20.11. The issue is seen multiple times a day under > ~20G > > traffic with stats collection once per second. > > > > > > Igor > > > > > > On Tue, Nov 17, 2020 at 11:56 AM Igor Ryzhov > > <iryz...@nfware.com<mailto:iryz...@nfware.com>> wrote: > > > When low and high registers are read separately, this opens the door > > > to a race condition: > > > - low register is read > > > - NIC updates the registers > > > - high register is read > > > > > > Because of this, we may end up with an incorrect counter value. > > > Let's read the registers in one shot, as it is done in Linux kernel > > > since the introduction of the i40e driver. > > > > > > Fixes: 4861cde46116 ("i40e: new poll mode driver") > > > Cc: sta...@dpdk.org<mailto:sta...@dpdk.org> > > > Signed-off-by: Igor Ryzhov > > > <iryz...@nfware.com<mailto:iryz...@nfware.com>> > > > --- > > > drivers/net/i40e/base/i40e_osdep.h | 10 ++++++++++ > > > drivers/net/i40e/i40e_ethdev.c | 10 +++++++--- > > > 2 files changed, 17 insertions(+), 3 deletions(-) > > > > > > diff --git a/drivers/net/i40e/base/i40e_osdep.h > > > b/drivers/net/i40e/base/i40e_osdep.h > > > index 64b15e1b6138..ebd687240006 100644 > > > --- a/drivers/net/i40e/base/i40e_osdep.h > > > +++ b/drivers/net/i40e/base/i40e_osdep.h > > > @@ -133,6 +133,14 @@ static inline uint32_t i40e_read_addr(volatile > void > > *addr) > > > return rte_le_to_cpu_32(I40E_PCI_REG(addr)); > > > } > > > > > > +#define I40E_PCI_REG64(reg) rte_read64(reg) > > > +#define I40E_PCI_REG64_ADDR(a, reg) \ > > > + ((volatile uint64_t *)((char *)(a)->hw_addr + (reg))) static > > > +inline uint64_t i40e_read64_addr(volatile void *addr) { > > > + return rte_le_to_cpu_64(I40E_PCI_REG64(addr)); > > > +} > > > + > > > #define I40E_PCI_REG_WRITE(reg, value) \ > > > rte_write32((rte_cpu_to_le_32(value)), reg) #define > > > I40E_PCI_REG_WRITE_RELAXED(reg, value) \ @@ -145,6 +153,8 @@ static > > > inline uint32_t i40e_read_addr(volatile void *addr) #define > > > I40E_WRITE_REG(hw, reg, value) \ > > > I40E_PCI_REG_WRITE(I40E_PCI_REG_ADDR((hw), (reg)), (value)) > > > > > > +#define I40E_READ_REG64(hw, reg) > > > +i40e_read64_addr(I40E_PCI_REG64_ADDR((hw), (reg))) > > > + > > > #define rd32(a, reg) i40e_read_addr(I40E_PCI_REG_ADDR((a), (reg))) > > > #define wr32(a, reg, value) \ > > > I40E_PCI_REG_WRITE(I40E_PCI_REG_ADDR((a), (reg)), (value)) > > > diff --git a/drivers/net/i40e/i40e_ethdev.c > > > b/drivers/net/i40e/i40e_ethdev.c index 74f4ac1f9d4e..53b1e9b9e067 > > > 100644 > > > --- a/drivers/net/i40e/i40e_ethdev.c > > > +++ b/drivers/net/i40e/i40e_ethdev.c > > > @@ -6451,9 +6451,13 @@ i40e_stat_update_48(struct i40e_hw *hw, { > > > uint64_t new_data; > > > > > > - new_data = (uint64_t)I40E_READ_REG(hw, loreg); > > > - new_data |= ((uint64_t)(I40E_READ_REG(hw, hireg) & > > > - I40E_16_BIT_MASK)) << I40E_32_BIT_WIDTH; > > > + if (hw->device_id == I40E_DEV_ID_QEMU) { > > > + new_data = (uint64_t)I40E_READ_REG(hw, loreg); > > > + new_data |= ((uint64_t)(I40E_READ_REG(hw, hireg) & > > > + I40E_16_BIT_MASK)) << > > I40E_32_BIT_WIDTH; > > > + } else { > > > + new_data = I40E_READ_REG64(hw, loreg); > > > + } > > > > > > if (!offset_loaded) > > > *offset = new_data; > > > -- > > > 2.29.2 > > > > > > > > > > > > >