From d3142c193dca9a2f6878f4128ce1aaf221bb3f99 Mon Sep 17 00:00:00 2001 From: Edward Cree Date: Mon, 29 Jun 2020 14:34:20 +0100 Subject: [PATCH] sfc: refactor EF10 stats handling Separate the generation-count handling from the format conversion, to make it easier to re-use both for EF100. Signed-off-by: Edward Cree Signed-off-by: David S. Miller --- drivers/net/ethernet/sfc/ef10.c | 68 ++++++++++++++++++++--------------------- drivers/net/ethernet/sfc/nic.c | 45 +++++++++++++++++++++++++++ drivers/net/ethernet/sfc/nic.h | 3 ++ 3 files changed, 82 insertions(+), 34 deletions(-) diff --git a/drivers/net/ethernet/sfc/ef10.c b/drivers/net/ethernet/sfc/ef10.c index c99fedb..49af06b 100644 --- a/drivers/net/ethernet/sfc/ef10.c +++ b/drivers/net/ethernet/sfc/ef10.c @@ -1279,6 +1279,14 @@ static int efx_ef10_dimension_resources(struct efx_nic *efx) return 0; } +static void efx_ef10_fini_nic(struct efx_nic *efx) +{ + struct efx_ef10_nic_data *nic_data = efx->nic_data; + + kfree(nic_data->mc_stats); + nic_data->mc_stats = NULL; +} + static int efx_ef10_init_nic(struct efx_nic *efx) { struct efx_ef10_nic_data *nic_data = efx->nic_data; @@ -1300,6 +1308,11 @@ static int efx_ef10_init_nic(struct efx_nic *efx) efx->must_realloc_vis = false; } + nic_data->mc_stats = kmalloc(efx->num_mac_stats * sizeof(__le64), + GFP_KERNEL); + if (!nic_data->mc_stats) + return -ENOMEM; + if (nic_data->must_restore_piobufs && nic_data->n_piobufs) { rc = efx_ef10_alloc_piobufs(efx, nic_data->n_piobufs); if (rc == 0) { @@ -1775,55 +1788,42 @@ static size_t efx_ef10_update_stats_common(struct efx_nic *efx, u64 *full_stats, return stats_count; } -static int efx_ef10_try_update_nic_stats_pf(struct efx_nic *efx) +static size_t efx_ef10_update_stats_pf(struct efx_nic *efx, u64 *full_stats, + struct rtnl_link_stats64 *core_stats) { struct efx_ef10_nic_data *nic_data = efx->nic_data; DECLARE_BITMAP(mask, EF10_STAT_COUNT); - __le64 generation_start, generation_end; u64 *stats = nic_data->stats; - __le64 *dma_stats; efx_ef10_get_stat_mask(efx, mask); - dma_stats = efx->stats_buffer.addr; - - generation_end = dma_stats[efx->num_mac_stats - 1]; - if (generation_end == EFX_MC_STATS_GENERATION_INVALID) - return 0; - rmb(); - efx_nic_update_stats(efx_ef10_stat_desc, EF10_STAT_COUNT, mask, - stats, efx->stats_buffer.addr, false); - rmb(); - generation_start = dma_stats[MC_CMD_MAC_GENERATION_START]; - if (generation_end != generation_start) - return -EAGAIN; + efx_nic_copy_stats(efx, nic_data->mc_stats); + efx_nic_update_stats(efx_ef10_stat_desc, EF10_STAT_COUNT, + mask, stats, nic_data->mc_stats, false); /* Update derived statistics */ efx_nic_fix_nodesc_drop_stat(efx, &stats[EF10_STAT_port_rx_nodesc_drops]); + /* MC Firmware reads RX_BYTES and RX_GOOD_BYTES from the MAC. + * It then calculates RX_BAD_BYTES and DMAs it to us with RX_BYTES. + * We report these as port_rx_ stats. We are not given RX_GOOD_BYTES. + * Here we calculate port_rx_good_bytes. + */ stats[EF10_STAT_port_rx_good_bytes] = stats[EF10_STAT_port_rx_bytes] - stats[EF10_STAT_port_rx_bytes_minus_good_bytes]; + + /* The asynchronous reads used to calculate RX_BAD_BYTES in + * MC Firmware are done such that we should not see an increase in + * RX_BAD_BYTES when a good packet has arrived. Unfortunately this + * does mean that the stat can decrease at times. Here we do not + * update the stat unless it has increased or has gone to zero + * (In the case of the NIC rebooting). + * Please see Bug 33781 for a discussion of why things work this way. + */ efx_update_diff_stat(&stats[EF10_STAT_port_rx_bad_bytes], stats[EF10_STAT_port_rx_bytes_minus_good_bytes]); efx_update_sw_stats(efx, stats); - return 0; -} - - -static size_t efx_ef10_update_stats_pf(struct efx_nic *efx, u64 *full_stats, - struct rtnl_link_stats64 *core_stats) -{ - int retry; - - /* If we're unlucky enough to read statistics during the DMA, wait - * up to 10ms for it to finish (typically takes <500us) - */ - for (retry = 0; retry < 100; ++retry) { - if (efx_ef10_try_update_nic_stats_pf(efx) == 0) - break; - udelay(100); - } return efx_ef10_update_stats_common(efx, full_stats, core_stats); } @@ -4033,7 +4033,7 @@ const struct efx_nic_type efx_hunt_a0_vf_nic_type = { .remove = efx_ef10_remove, .dimension_resources = efx_ef10_dimension_resources, .init = efx_ef10_init_nic, - .fini = efx_port_dummy_op_void, + .fini = efx_ef10_fini_nic, .map_reset_reason = efx_ef10_map_reset_reason, .map_reset_flags = efx_ef10_map_reset_flags, .reset = efx_ef10_reset, @@ -4142,7 +4142,7 @@ const struct efx_nic_type efx_hunt_a0_nic_type = { .remove = efx_ef10_remove, .dimension_resources = efx_ef10_dimension_resources, .init = efx_ef10_init_nic, - .fini = efx_port_dummy_op_void, + .fini = efx_ef10_fini_nic, .map_reset_reason = efx_ef10_map_reset_reason, .map_reset_flags = efx_ef10_map_reset_flags, .reset = efx_ef10_reset, diff --git a/drivers/net/ethernet/sfc/nic.c b/drivers/net/ethernet/sfc/nic.c index b0baa70..ac66305 100644 --- a/drivers/net/ethernet/sfc/nic.c +++ b/drivers/net/ethernet/sfc/nic.c @@ -20,6 +20,8 @@ #include "farch_regs.h" #include "io.h" #include "workarounds.h" +#include "mcdi_port_common.h" +#include "mcdi_pcol.h" /************************************************************************** * @@ -471,6 +473,49 @@ size_t efx_nic_describe_stats(const struct efx_hw_stat_desc *desc, size_t count, } /** + * efx_nic_copy_stats - Copy stats from the DMA buffer in to an + * intermediate buffer. This is used to get a consistent + * set of stats while the DMA buffer can be written at any time + * by the NIC. + * @efx: The associated NIC. + * @dest: Destination buffer. Must be the same size as the DMA buffer. + */ +int efx_nic_copy_stats(struct efx_nic *efx, __le64 *dest) +{ + __le64 *dma_stats = efx->stats_buffer.addr; + __le64 generation_start, generation_end; + int rc = 0, retry; + + if (!dest) + return 0; + + if (!dma_stats) + goto return_zeroes; + + /* If we're unlucky enough to read statistics during the DMA, wait + * up to 10ms for it to finish (typically takes <500us) + */ + for (retry = 0; retry < 100; ++retry) { + generation_end = dma_stats[efx->num_mac_stats - 1]; + if (generation_end == EFX_MC_STATS_GENERATION_INVALID) + goto return_zeroes; + rmb(); + memcpy(dest, dma_stats, efx->num_mac_stats * sizeof(__le64)); + rmb(); + generation_start = dma_stats[MC_CMD_MAC_GENERATION_START]; + if (generation_end == generation_start) + return 0; /* return good data */ + udelay(100); + } + + rc = -EIO; + +return_zeroes: + memset(dest, 0, efx->num_mac_stats * sizeof(u64)); + return rc; +} + +/** * efx_nic_update_stats - Convert statistics DMA buffer to array of u64 * @desc: Array of &struct efx_hw_stat_desc describing the DMA buffer * layout. DMA widths of 0, 16, 32 and 64 are supported; where diff --git a/drivers/net/ethernet/sfc/nic.h b/drivers/net/ethernet/sfc/nic.h index 8f73c5d..792907ae 100644 --- a/drivers/net/ethernet/sfc/nic.h +++ b/drivers/net/ethernet/sfc/nic.h @@ -368,6 +368,7 @@ enum { * @piobuf_size: size of a single PIO buffer * @must_restore_piobufs: Flag: PIO buffers have yet to be restored after MC * reboot + * @mc_stats: Scratch buffer for converting statistics to the kernel's format * @stats: Hardware statistics * @workaround_35388: Flag: firmware supports workaround for bug 35388 * @workaround_26807: Flag: firmware supports workaround for bug 26807 @@ -404,6 +405,7 @@ struct efx_ef10_nic_data { unsigned int piobuf_handle[EF10_TX_PIOBUF_COUNT]; u16 piobuf_size; bool must_restore_piobufs; + __le64 *mc_stats; u64 stats[EF10_STAT_COUNT]; bool workaround_35388; bool workaround_26807; @@ -674,6 +676,7 @@ void efx_nic_get_regs(struct efx_nic *efx, void *buf); size_t efx_nic_describe_stats(const struct efx_hw_stat_desc *desc, size_t count, const unsigned long *mask, u8 *names); +int efx_nic_copy_stats(struct efx_nic *efx, __le64 *dest); void efx_nic_update_stats(const struct efx_hw_stat_desc *desc, size_t count, const unsigned long *mask, u64 *stats, const void *dma_buf, bool accumulate); -- 2.7.4