From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id E15BA212F98; Wed, 28 Jan 2026 18:11:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=13.77.154.182 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769623909; cv=none; b=mBpqVwB511mMB1CuOXKaaJbJV58LHDBN/e4GcRzU9K77lhVvCDm1X/vhmiALQmt0TSz86bRRPeaL/kcnzI7ysKaI2aqOVnqhtWo1pgDtCNWTCVM+ZVlSsY39akYiBDdO1JwR9/s5tCmgMHPzLH8imWZ787zXiSoGNGaDEH+hAAE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769623909; c=relaxed/simple; bh=Ammg5xkt22af/IRdK1mTCbt+YsCki8ypDeFLlhDxRXc=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=Ym4+eheL+vqXrY7XDCj28EEwl9xbKakcCk9K2mcCVOOkdjB0ByFb5xdTRi4Zi91wEdLm9HXhb+vDxdxOWEuUMc7c3/j1G7njM/+5uX4ZlpWLk2u7lgT+MQkz+Ha+Bd1ee3h6+b9aVRVwiHFd2wW5XgU0f1ZtGY43earh8MQSM8Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com; spf=pass smtp.mailfrom=linux.microsoft.com; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b=jbBpzHuC; arc=none smtp.client-ip=13.77.154.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="jbBpzHuC" Received: by linux.microsoft.com (Postfix, from userid 1032) id D086620B7165; Wed, 28 Jan 2026 10:11:47 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com D086620B7165 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1769623907; bh=1UyaT1G76cRZkQR0hLY9kvb5qfe9T2OJS3VOkTL96N8=; h=From:To:Cc:Subject:Date:From; b=jbBpzHuCsk0CN22Z9lWfJoNVaT+0s4gp5qSgCYHkXi5Dz37QnswZyFMdUnn7vWXGf Sz4lwxzspHlbYPGsw8QeEMShwSLyDVm/9jFJ5Vu3z07ZokDGjGLVMTlSscXioRe78U Zpa/3htwnK9A9ULKlzIuVxikUVQ65JjtU5C8+ZS8= From: Nuno Das Neves To: linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org, mhklinux@outlook.com, skinsburskii@linux.microsoft.com Cc: kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, longli@microsoft.com, prapal@linux.microsoft.com, mrathor@linux.microsoft.com, paekkaladevi@linux.microsoft.com, Nuno Das Neves Subject: [PATCH v6 0/7] mshv: Debugfs interface for mshv_root Date: Wed, 28 Jan 2026 10:11:39 -0800 Message-ID: <20260128181146.517708-1-nunodasneves@linux.microsoft.com> X-Mailer: git-send-email 2.43.7 Precedence: bulk X-Mailing-List: linux-hyperv@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Expose hypervisor, logical processor, partition, and virtual processor statistics via debugfs. These are provided by mapping 'stats' pages via hypercall. Patch #1: Update hv_call_map_stats_page() to return success when HV_STATS_AREA_PARENT is unavailable, which is the case on some hypervisor versions, where it can fall back to HV_STATS_AREA_SELF Patch #2: Use struct hv_stats_page pointers instead of void * Patch #3: Make mshv_vp_stats_map/unmap() more flexible to use with debugfs code Patch #4: Always map vp stats page regardless of scheduler, to reuse in debugfs Patch #5: Change to hv_stats_page definition and VpRootDispatchThreadBlocked Patch #6: Introduce the definitions needed for the various stats pages Patch #7: Add mshv_debugfs.c, and integrate it with the mshv_root driver to expose the partition and VP stats. --- Changes in v6: - Fix whitespace and other checkpatch issues [Michael] Changes in v5: - Rename hv_counters.c to mshv_debugfs_counters.c [Michael] - Clarify unusual inclusion of mshv_debugfs_counters.c with comment. After discussion it is still included directly to keep things simple. Including arrays with unspecified size via a header means sizeof() cannot be used on the array. - Error if mshv_debugfs_counters.c is included elsewhere than mshv_debugfs.c - Use array index as stats page index to save space [Stanislav] - Enforce HV_STATS_AREA_PARENT and SELF fit in NUM_STATS_AREAS with static_assert and clarify with comment [Michael] - Return to using lp count from hv stats page for mshv_lps_count [Michael] - Use nr_cpu_ids instead of num_possible_cpus() [Michael] - Set mshv_lps_stats[idx] and the array itself to NULL on unmap and cleanup [Michael] - Rename HvLogicalProcessors and VpRootDispatchThreadBlocked to Linux style - Translate Linux cpu index to vp index via hv_vp_index on partition destroy [Michael] - Minor formatting cleanups [Michael] Changes in v4: - Put the counters definitions in static arrays in hv_counters.c, instead of as enums in hvhdk.h [Michael] - Due to the above, add an additional patch (#5) to simplify hv_stats_page, and retain the enum definition at the top of mshv_root_main.c for use with VpRootDispatchThreadBlocked. That is the only remaining use of the counter enum. - Due to the above, use num_present_cpus() as the number of LPs to map stats pages for - this number shouldn't change at runtime because the hypervisor doesn't support hotplug for root partition. Changes in v3: - Add 3 small refactor/cleanup patches (patches 2,3,4) from Stanislav. These simplify some of the debugfs code, and fix issues with mapping VP stats on L1VH. - Fix cleanup of parent stats dentries on module removal (via squashing some internal patches into patch #6) [Praveen] - Remove unused goto label [Stanislav, kernel bot] - Use struct hv_stats_page * instead of void * in mshv_debugfs.c [Stanislav] - Remove some redundant variables [Stanislav] - Rename debugfs dentry fields for brevity [Stanislav] - Use ERR_CAST() for the dentry error pointer returned from lp_debugfs_stats_create() [Stanislav] - Fix leak of pages allocated for lp stats mappings by storing them in an array [Michael] - Add comments to clarify PARENT vs SELF usage and edge cases [Michael] - Add VpLoadAvg for x86 and print the stat [Michael] - Add NUM_STATS_AREAS for array sizing in mshv_debugfs.c [Michael] Changes in v2: - Remove unnecessary pr_debug_once() in patch 1 [Stanislav Kinsburskii] - CONFIG_X86 -> CONFIG_X86_64 in patch 2 [Stanislav Kinsburskii] --- Nuno Das Neves (3): mshv: Update hv_stats_page definitions mshv: Add data for printing stats page counters mshv: Add debugfs to view hypervisor statistics Purna Pavan Chandra Aekkaladevi (1): mshv: Ignore second stats page map result failure Stanislav Kinsburskii (3): mshv: Use typed hv_stats_page pointers mshv: Improve mshv_vp_stats_map/unmap(), add them to mshv_root.h mshv: Always map child vp stats pages regardless of scheduler type drivers/hv/Makefile | 1 + drivers/hv/mshv_debugfs.c | 726 +++++++++++++++++++++++++++++ drivers/hv/mshv_debugfs_counters.c | 490 +++++++++++++++++++ drivers/hv/mshv_root.h | 49 +- drivers/hv/mshv_root_hv_call.c | 64 ++- drivers/hv/mshv_root_main.c | 140 +++--- include/hyperv/hvhdk.h | 7 + 7 files changed, 1412 insertions(+), 65 deletions(-) create mode 100644 drivers/hv/mshv_debugfs.c create mode 100644 drivers/hv/mshv_debugfs_counters.c -- 2.34.1