| #!/usr/bin/env python3 |
| # SPDX-License-Identifier: GPL-2.0 |
| |
| """ |
| Driver-related behavior tests for RSS. |
| """ |
| |
| from lib.py import ksft_run, ksft_exit, ksft_eq, ksft_ge |
| from lib.py import ksft_variants, KsftNamedVariant, KsftSkipEx, ksft_raises |
| from lib.py import defer, ethtool, CmdExitFailure |
| from lib.py import EthtoolFamily, NlError |
| from lib.py import NetDrvEnv |
| |
| |
| def _is_power_of_two(n): |
| return n > 0 and (n & (n - 1)) == 0 |
| |
| |
| def _get_rss(cfg, context=0): |
| return ethtool(f"-x {cfg.ifname} context {context}", json=True)[0] |
| |
| |
| def _test_rss_indir_size(cfg, qcnt, context=0): |
| """Test that indirection table size is at least 4x queue count.""" |
| ethtool(f"-L {cfg.ifname} combined {qcnt}") |
| |
| rss = _get_rss(cfg, context=context) |
| indir = rss['rss-indirection-table'] |
| ksft_ge(len(indir), 4 * qcnt, "Table smaller than 4x") |
| return len(indir) |
| |
| |
| def _maybe_create_context(cfg, create_context): |
| """ Either create a context and return its ID or return 0 for main ctx """ |
| if not create_context: |
| return 0 |
| try: |
| ctx = cfg.ethnl.rss_create_act({'header': {'dev-index': cfg.ifindex}}) |
| ctx_id = ctx['context'] |
| defer(cfg.ethnl.rss_delete_act, |
| {'header': {'dev-index': cfg.ifindex}, 'context': ctx_id}) |
| except NlError: |
| raise KsftSkipEx("Device does not support additional RSS contexts") |
| |
| return ctx_id |
| |
| |
| def _require_dynamic_indir_size(cfg, ch_max): |
| """Skip if the device does not dynamically size its indirection table.""" |
| ethtool(f"-X {cfg.ifname} default") |
| ethtool(f"-L {cfg.ifname} combined 2") |
| small = len(_get_rss(cfg)['rss-indirection-table']) |
| ethtool(f"-L {cfg.ifname} combined {ch_max}") |
| large = len(_get_rss(cfg)['rss-indirection-table']) |
| |
| if small == large: |
| raise KsftSkipEx("Device does not dynamically size indirection table") |
| |
| |
| @ksft_variants([ |
| KsftNamedVariant("main", False), |
| KsftNamedVariant("ctx", True), |
| ]) |
| def indir_size_4x(cfg, create_context): |
| """ |
| Test that the indirection table has at least 4 entries per queue. |
| Empirically network-heavy workloads like memcache suffer with the 33% |
| imbalance of a 2x indirection table size. |
| 4x table translates to a 16% imbalance. |
| """ |
| channels = cfg.ethnl.channels_get({'header': {'dev-index': cfg.ifindex}}) |
| ch_max = channels.get('combined-max', 0) |
| qcnt = channels['combined-count'] |
| |
| if ch_max < 3: |
| raise KsftSkipEx(f"Not enough queues for the test: max={ch_max}") |
| |
| defer(ethtool, f"-L {cfg.ifname} combined {qcnt}") |
| ethtool(f"-L {cfg.ifname} combined 3") |
| |
| ctx_id = _maybe_create_context(cfg, create_context) |
| |
| indir_sz = _test_rss_indir_size(cfg, 3, context=ctx_id) |
| |
| # Test with max queue count (max - 1 if max is a power of two) |
| test_max = ch_max - 1 if _is_power_of_two(ch_max) else ch_max |
| if test_max > 3 and indir_sz < test_max * 4: |
| _test_rss_indir_size(cfg, test_max, context=ctx_id) |
| |
| |
| @ksft_variants([ |
| KsftNamedVariant("main", False), |
| KsftNamedVariant("ctx", True), |
| ]) |
| def resize_periodic(cfg, create_context): |
| """Test that a periodic indirection table survives channel changes. |
| |
| Set a non-default periodic table ([3, 2, 1, 0] x N) via netlink, |
| reduce channels to trigger a fold, then increase to trigger an |
| unfold. Using a reversed pattern (instead of [0, 1, 2, 3]) ensures |
| the test can distinguish a correct fold from a driver that silently |
| resets the table to defaults. Verify the exact pattern is preserved |
| and the size tracks the channel count. |
| """ |
| channels = cfg.ethnl.channels_get({'header': {'dev-index': cfg.ifindex}}) |
| ch_max = channels.get('combined-max', 0) |
| qcnt = channels['combined-count'] |
| |
| if ch_max < 4: |
| raise KsftSkipEx(f"Not enough queues for the test: max={ch_max}") |
| |
| defer(ethtool, f"-L {cfg.ifname} combined {qcnt}") |
| |
| _require_dynamic_indir_size(cfg, ch_max) |
| |
| ctx_id = _maybe_create_context(cfg, create_context) |
| |
| # Set a non-default periodic pattern via netlink. |
| # Send only 4 entries (user_size=4) so the kernel replicates it |
| # to fill the device table. This allows folding down to 4 entries. |
| rss = _get_rss(cfg, context=ctx_id) |
| orig_size = len(rss['rss-indirection-table']) |
| pattern = [3, 2, 1, 0] |
| req = {'header': {'dev-index': cfg.ifindex}, 'indir': pattern} |
| if ctx_id: |
| req['context'] = ctx_id |
| else: |
| defer(ethtool, f"-X {cfg.ifname} default") |
| cfg.ethnl.rss_set(req) |
| |
| # Shrink — should fold |
| ethtool(f"-L {cfg.ifname} combined 4") |
| rss = _get_rss(cfg, context=ctx_id) |
| indir = rss['rss-indirection-table'] |
| |
| ksft_ge(orig_size, len(indir), "Table did not shrink") |
| ksft_eq(indir, [3, 2, 1, 0] * (len(indir) // 4), |
| "Folded table has wrong pattern") |
| |
| # Grow back — should unfold |
| ethtool(f"-L {cfg.ifname} combined {ch_max}") |
| rss = _get_rss(cfg, context=ctx_id) |
| indir = rss['rss-indirection-table'] |
| |
| ksft_eq(len(indir), orig_size, "Table size not restored") |
| ksft_eq(indir, [3, 2, 1, 0] * (len(indir) // 4), |
| "Unfolded table has wrong pattern") |
| |
| |
| @ksft_variants([ |
| KsftNamedVariant("main", False), |
| KsftNamedVariant("ctx", True), |
| ]) |
| def resize_below_user_size_reject(cfg, create_context): |
| """Test that shrinking below user_size is rejected. |
| |
| Send a table via netlink whose size (user_size) sits between |
| the small and large device table sizes. The table is periodic, |
| so folding would normally succeed, but the user_size floor must |
| prevent it. |
| """ |
| channels = cfg.ethnl.channels_get({'header': {'dev-index': cfg.ifindex}}) |
| ch_max = channels.get('combined-max', 0) |
| qcnt = channels['combined-count'] |
| |
| if ch_max < 4: |
| raise KsftSkipEx(f"Not enough queues for the test: max={ch_max}") |
| |
| defer(ethtool, f"-L {cfg.ifname} combined {qcnt}") |
| |
| _require_dynamic_indir_size(cfg, ch_max) |
| |
| ctx_id = _maybe_create_context(cfg, create_context) |
| |
| # Measure the table size at max channels |
| rss = _get_rss(cfg, context=ctx_id) |
| big_size = len(rss['rss-indirection-table']) |
| |
| # Measure the table size at reduced channels |
| ethtool(f"-L {cfg.ifname} combined 4") |
| rss = _get_rss(cfg, context=ctx_id) |
| small_size = len(rss['rss-indirection-table']) |
| ethtool(f"-L {cfg.ifname} combined {ch_max}") |
| |
| if small_size >= big_size: |
| raise KsftSkipEx("Table did not shrink at reduced channels") |
| |
| # Find a user_size |
| user_size = None |
| for div in [2, 4]: |
| candidate = big_size // div |
| if candidate > small_size and big_size % candidate == 0: |
| user_size = candidate |
| break |
| if user_size is None: |
| raise KsftSkipEx("No suitable user_size between small and big table") |
| |
| # Send a periodic sub-table of exactly user_size entries. |
| # Pattern safe for 4 channels. |
| pattern = [0, 1, 2, 3] * (user_size // 4) |
| if len(pattern) != user_size: |
| raise KsftSkipEx(f"user_size ({user_size}) not divisible by 4") |
| req = {'header': {'dev-index': cfg.ifindex}, 'indir': pattern} |
| if ctx_id: |
| req['context'] = ctx_id |
| else: |
| defer(ethtool, f"-X {cfg.ifname} default") |
| cfg.ethnl.rss_set(req) |
| |
| # Shrink channels — table would go to small_size < user_size. |
| # The table is periodic so folding would work, but user_size |
| # floor must reject it. |
| with ksft_raises(CmdExitFailure): |
| ethtool(f"-L {cfg.ifname} combined 4") |
| |
| |
| @ksft_variants([ |
| KsftNamedVariant("main", False), |
| KsftNamedVariant("ctx", True), |
| ]) |
| def resize_nonperiodic_reject(cfg, create_context): |
| """Test that a non-periodic table blocks channel reduction. |
| |
| Set equal weight across all queues so the table is not periodic |
| at any smaller size, then verify channel reduction is rejected. |
| An additional context with a periodic table is created to verify |
| that validation catches the non-periodic one even when others |
| are fine. |
| """ |
| channels = cfg.ethnl.channels_get({'header': {'dev-index': cfg.ifindex}}) |
| ch_max = channels.get('combined-max', 0) |
| qcnt = channels['combined-count'] |
| |
| if ch_max < 4: |
| raise KsftSkipEx(f"Not enough queues for the test: max={ch_max}") |
| |
| defer(ethtool, f"-L {cfg.ifname} combined {qcnt}") |
| |
| _require_dynamic_indir_size(cfg, ch_max) |
| |
| ctx_id = _maybe_create_context(cfg, create_context) |
| ctx_ref = f"context {ctx_id}" if ctx_id else "" |
| |
| # Create an extra context with a periodic (foldable) table so that |
| # the validation must iterate all contexts to find the bad one. |
| extra_ctx = _maybe_create_context(cfg, True) |
| ethtool(f"-X {cfg.ifname} context {extra_ctx} equal 2") |
| |
| ethtool(f"-X {cfg.ifname} {ctx_ref} equal {ch_max}") |
| if not create_context: |
| defer(ethtool, f"-X {cfg.ifname} default") |
| |
| with ksft_raises(CmdExitFailure): |
| ethtool(f"-L {cfg.ifname} combined 2") |
| |
| |
| @ksft_variants([ |
| KsftNamedVariant("main", False), |
| KsftNamedVariant("ctx", True), |
| ]) |
| def resize_nonperiodic_no_corruption(cfg, create_context): |
| """Test that a failed resize does not corrupt table or channel count. |
| |
| Set a non-periodic table, attempt a channel reduction (which must |
| fail), then verify both the indirection table contents and the |
| channel count are unchanged. |
| """ |
| channels = cfg.ethnl.channels_get({'header': {'dev-index': cfg.ifindex}}) |
| ch_max = channels.get('combined-max', 0) |
| qcnt = channels['combined-count'] |
| |
| if ch_max < 4: |
| raise KsftSkipEx(f"Not enough queues for the test: max={ch_max}") |
| |
| defer(ethtool, f"-L {cfg.ifname} combined {qcnt}") |
| |
| _require_dynamic_indir_size(cfg, ch_max) |
| |
| ctx_id = _maybe_create_context(cfg, create_context) |
| ctx_ref = f"context {ctx_id}" if ctx_id else "" |
| |
| ethtool(f"-X {cfg.ifname} {ctx_ref} equal {ch_max}") |
| if not create_context: |
| defer(ethtool, f"-X {cfg.ifname} default") |
| |
| rss_before = _get_rss(cfg, context=ctx_id) |
| |
| with ksft_raises(CmdExitFailure): |
| ethtool(f"-L {cfg.ifname} combined 2") |
| |
| rss_after = _get_rss(cfg, context=ctx_id) |
| ksft_eq(rss_after['rss-indirection-table'], |
| rss_before['rss-indirection-table'], |
| "Indirection table corrupted after failed resize") |
| |
| channels = cfg.ethnl.channels_get({'header': {'dev-index': cfg.ifindex}}) |
| ksft_eq(channels['combined-count'], ch_max, |
| "Channel count changed after failed resize") |
| |
| |
| def main() -> None: |
| """ Ksft boiler plate main """ |
| with NetDrvEnv(__file__) as cfg: |
| cfg.ethnl = EthtoolFamily() |
| ksft_run([indir_size_4x, resize_periodic, |
| resize_below_user_size_reject, |
| resize_nonperiodic_reject, |
| resize_nonperiodic_no_corruption], args=(cfg, )) |
| ksft_exit() |
| |
| |
| if __name__ == "__main__": |
| main() |
