On 10/07/2020 15:23, Oliver O'Halloran wrote:
> Rework the PE allocation logic to allow allocating blocks of PEs rather
> than individually. We'll use this to allocate contigious blocks of PEs for
> the SR-IOVs.
The patch does not do just this, it also adds missing mutexes (which is
good) but still misses them in pnv_pci_sriov_disable() and
pnv_pci_ioda_pe_dump().
>
> Signed-off-by: Oliver O'Halloran <ooh...@gmail.com>
> ---
> arch/powerpc/platforms/powernv/pci-ioda.c | 41 ++++++++++++++++++-----
> arch/powerpc/platforms/powernv/pci.h | 2 +-
> 2 files changed, 34 insertions(+), 9 deletions(-)
>
> diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c
> b/arch/powerpc/platforms/powernv/pci-ioda.c
> index 2d36a9ebf0e9..c9c25fb0783c 100644
> --- a/arch/powerpc/platforms/powernv/pci-ioda.c
> +++ b/arch/powerpc/platforms/powernv/pci-ioda.c
> @@ -145,23 +145,45 @@ static void pnv_ioda_reserve_pe(struct pnv_phb *phb,
> int pe_no)
> return;
> }
>
> + mutex_lock(&phb->ioda.pe_alloc_mutex);
> if (test_and_set_bit(pe_no, phb->ioda.pe_alloc))
> pr_debug("%s: PE %x was reserved on PHB#%x\n",
> __func__, pe_no, phb->hose->global_number);
> + mutex_unlock(&phb->ioda.pe_alloc_mutex);
>
> pnv_ioda_init_pe(phb, pe_no);
> }
>
> -struct pnv_ioda_pe *pnv_ioda_alloc_pe(struct pnv_phb *phb)
> +struct pnv_ioda_pe *pnv_ioda_alloc_pe(struct pnv_phb *phb, int count)
> {
> - long pe;
> + struct pnv_ioda_pe *ret = NULL;
> + int run = 0, pe, i;
>
> + mutex_lock(&phb->ioda.pe_alloc_mutex);
> +
> + /* scan backwards for a run of @count cleared bits */
> for (pe = phb->ioda.total_pe_num - 1; pe >= 0; pe--) {
> - if (!test_and_set_bit(pe, phb->ioda.pe_alloc))
> - return pnv_ioda_init_pe(phb, pe);
> + if (test_bit(pe, phb->ioda.pe_alloc)) {
> + run = 0;
> + continue;
> + }
> +
> + run++;
> + if (run == count)
> + break;
> }
> + if (run != count)
> + goto out;
>
> - return NULL;
> + for (i = pe; i < pe + count; i++) {
> + set_bit(i, phb->ioda.pe_alloc);
> + pnv_ioda_init_pe(phb, i);
> + }
> + ret = &phb->ioda.pe_array[pe];
> +
> +out:
> + mutex_unlock(&phb->ioda.pe_alloc_mutex);
> + return ret;
> }
>
> void pnv_ioda_free_pe(struct pnv_ioda_pe *pe)
> @@ -173,7 +195,10 @@ void pnv_ioda_free_pe(struct pnv_ioda_pe *pe)
> WARN_ON(pe->npucomp); /* NPUs for nvlink are not supposed to be freed */
> kfree(pe->npucomp);
> memset(pe, 0, sizeof(struct pnv_ioda_pe));
> +
> + mutex_lock(&phb->ioda.pe_alloc_mutex);
> clear_bit(pe_num, phb->ioda.pe_alloc);
> + mutex_unlock(&phb->ioda.pe_alloc_mutex);
> }
>
> /* The default M64 BAR is shared by all PEs */
> @@ -976,7 +1001,7 @@ static struct pnv_ioda_pe *pnv_ioda_setup_dev_PE(struct
> pci_dev *dev)
> if (pdn->pe_number != IODA_INVALID_PE)
> return NULL;
>
> - pe = pnv_ioda_alloc_pe(phb);
> + pe = pnv_ioda_alloc_pe(phb, 1);
> if (!pe) {
> pr_warn("%s: Not enough PE# available, disabling device\n",
> pci_name(dev));
> @@ -1047,7 +1072,7 @@ static struct pnv_ioda_pe *pnv_ioda_setup_bus_PE(struct
> pci_bus *bus, bool all)
>
> /* The PE number isn't pinned by M64 */
> if (!pe)
> - pe = pnv_ioda_alloc_pe(phb);
> + pe = pnv_ioda_alloc_pe(phb, 1);
>
> if (!pe) {
> pr_warn("%s: Not enough PE# available for PCI bus %04x:%02x\n",
> @@ -3065,7 +3090,7 @@ static void __init pnv_pci_init_ioda_phb(struct
> device_node *np,
> pnv_ioda_reserve_pe(phb, phb->ioda.root_pe_idx);
> } else {
> /* otherwise just allocate one */
> - root_pe = pnv_ioda_alloc_pe(phb);
> + root_pe = pnv_ioda_alloc_pe(phb, 1);
> phb->ioda.root_pe_idx = root_pe->pe_number;
> }
>
> diff --git a/arch/powerpc/platforms/powernv/pci.h
> b/arch/powerpc/platforms/powernv/pci.h
> index 58c97e60c3db..b4c9bdba7217 100644
> --- a/arch/powerpc/platforms/powernv/pci.h
> +++ b/arch/powerpc/platforms/powernv/pci.h
> @@ -223,7 +223,7 @@ int pnv_ioda_deconfigure_pe(struct pnv_phb *phb, struct
> pnv_ioda_pe *pe);
> void pnv_pci_ioda2_setup_dma_pe(struct pnv_phb *phb, struct pnv_ioda_pe *pe);
> void pnv_pci_ioda2_release_pe_dma(struct pnv_ioda_pe *pe);
>
> -struct pnv_ioda_pe *pnv_ioda_alloc_pe(struct pnv_phb *phb);
> +struct pnv_ioda_pe *pnv_ioda_alloc_pe(struct pnv_phb *phb, int count);
> void pnv_ioda_free_pe(struct pnv_ioda_pe *pe);
>
> #ifdef CONFIG_PCI_IOV
>
--
Alexey
