* Re: [PATCH v3 1/5] KVM: PPC: Book3S HV: Validate arch_compat against host compatibility mode
From: Harsh Prateek Bora @ 2026-06-03 6:31 UTC (permalink / raw)
To: Ritesh Harjani (IBM), Madhavan Srinivasan, Vaibhav Jain,
Amit Machhiwal
Cc: linuxppc-dev, Anushree Mathur, Paolo Bonzini, Nicholas Piggin,
Michael Ellerman, Christophe Leroy (CS GROUP), Jonathan Corbet,
Shuah Khan, kvm, linux-kernel, linux-doc, lkp
In-Reply-To: <bjdsw43g.ritesh.list@gmail.com>
On 03/06/26 11:35 am, Ritesh Harjani (IBM) wrote:
> Harsh Prateek Bora <harshpb@linux.ibm.com> writes:
>
>>> amit, can you just post this alone as a separate patch, so that we could
>>> pull it for 7.2 merge?
>>>
>>
>> FWIW, b4 am -P1 <mbox> should fetch this patch alone (and not the entire
>> series), See b4 am --help for more options to select a subset of patches.
>>
>
> I agree, however as an FYI in this case -
> I had few review comments on PATCH-1 here [1] - which along with the
> commit msg changes, also had a code change involved, so IMO, it's still
> a good idea if Amit can test and send an updated patch separately for this -
> to be pulled in for 7.2.
>
> [1]: https://lore.kernel.org/linuxppc-dev/pl2g6xbz.ritesh.list@gmail.com/
>
>
> Replying to Vaibhav comment here so that we can reach to the conclusion
> at one place.
>
>> Hence IMHO, this patch can be marked for stable tree and potential
>> candidate for 7.2 merge window. But dont see applicability of a 'fixes'
>> tag to this patch
>
> I agree, we need not use a fixes tag then. So, we shall mark this
> with v6.10 tag then.
>
> Cc: stable@vger.kernel.org # v6.10+
>
> (I calculated this based on when Power11 was added:
> git tag --contains c2ed087ed35ca | grep -E "^v" |head -1
> v6.10
> )
Thanks for help with this, Ritesh!
>
> -ritesh
>
^ permalink raw reply
* Re: [PATCH v3] cpu/hotplug: Fix NULL kobject warning in cpuhp_smt_enable()
From: Jinjie Ruan @ 2026-06-03 6:38 UTC (permalink / raw)
To: Will Deacon
Cc: catalin.marinas, corbet, skhan, punit.agrawal, jic23,
osama.abdelkader, chenl311, fengchengwen, suzuki.poulose, maz,
lpieralisi, timothy.hayes, sascha.bischoff, arnd,
mrigendra.chaubey, pierre.gondois, dietmar.eggemann, yangyicong,
sudeep.holla, linux-arm-kernel, linux-doc, linux-kernel
In-Reply-To: <ah65zXlOH6a9geD9@willie-the-truck>
On 6/2/2026 7:09 PM, Will Deacon wrote:
> On Wed, May 20, 2026 at 10:20:23AM +0800, Jinjie Ruan wrote:
>> On arm64, when booting with `maxcpus` greater than the number of present
>> CPUs (e.g., QEMU -smp cpus=4,maxcpus=8), some CPUs are marked as 'present'
>> but have not yet been registered via register_cpu(). Consequently,
>> the per-cpu device objects for these CPUs are not yet initialized.
>>
>> In cpuhp_smt_enable(), the code iterates over all present CPUs. Calling
>> _cpu_up() for these unregistered CPUs eventually leads to
>> sysfs_create_group() being called with a NULL kobject (or a kobject
>> without a directory), triggering the following warning in
>> fs/sysfs/group.c:
>>
>> if (WARN_ON(!kobj || (!update && !kobj->sd)))
>> return -EINVAL;
>>
>> When booting with ACPI, arm64 smp_prepare_cpus() currently sets all
>> enumerated CPUs as "present" regardless of their status in the MADT. This
>> causes issues with SMT hotplug control. For instance, with QEMU's
>> "-smp 4,maxcpus=8" configuration, the MADT GICC entries are populated as
>> follows: the first four CPUs are marked Enabled while the remaining four
>> are marked Online Capable to support potential hot-plugging.
>>
>> Fix this by:
>>
>> 1. When booting with ACPI, checking the ACPI_MADT_ENABLED flag in the GICC
>> entry before calling set_cpu_present() during SMP initialization.
>>
>> 2. Properly managing the present mask in acpi_map_cpu() and
>> acpi_unmap_cpu() to support actual CPU hotplug events, This aligns with
>> other architectures like x86 and LoongArch.
>>
>> 3. Update the arm64 CPU hotplug documentation to no longer state that all
>> online-capable vCPUs are marked as present by the kernel at boot time.
>>
>> This ensures that only physically available or explicitly enabled CPUs
>> are in the present mask, keeping the SMT control logic consistent with
>> the actual hardware state.
>
> Please can you check the Sashiko review comment?
>
> https://sashiko.dev/#/patchset/20260520022023.126670-1-ruanjinjie@huawei.com
Hi, all,
I think commit eba4675008a6 ("arm64: arch_register_cpu() variant to
check if an ACPI handle is now available.") introduced this bug.
It introduced an architectural safety block inside
arch_unregister_cpu(). If a hot-unplug operation is determined to be a
physical hardware removal (where _STA evaluates to
!ACPI_STA_DEVICE_PRESENT), it aborts the unregistration transaction
early to protect unreadied arm64 infrastructure, thereby skipping
unregister_cpu().
However, the generic ACPI processor driver path in
acpi_processor_post_eject() currently treats arch_unregister_cpu() as
an unconditional void operation. When arch_unregister_cpu() bails out
early, the subsequent cleanup flow blindly proceeds to call
acpi_unmap_cpu(), clears global per-cpu processor arrays, and
unconditionally free the 'struct acpi_processor' object.
I think we can fix this by:
1. Refactoring arch_unregister_cpu() to return an integer
transaction status. It returns -EOPNOTSUPP when aborting due to physical
hot-remove blocking, -EINVAL/-EIO on firmware failures, and 0 only upon
successful unregistration.
2. Guarding the downstream execution flow in
acpi_processor_post_eject(). If arch_unregister_cpu() returns a error
code, the hot-unplug transaction is considered aborted.
What do you think about this fix?
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index 1aa324104afb..f451c9c82212 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -531,29 +531,30 @@ int arch_register_cpu(int cpu)
}
#ifdef CONFIG_ACPI_HOTPLUG_CPU
-void arch_unregister_cpu(int cpu)
+int arch_unregister_cpu(int cpu)
{
acpi_handle acpi_handle = acpi_get_processor_handle(cpu);
struct cpu *c = &per_cpu(cpu_devices, cpu);
- acpi_status status;
unsigned long long sta;
+ acpi_status status;
if (!acpi_handle) {
pr_err_once("Removing a CPU without associated ACPI
handle\n");
- return;
+ return -EINVAL;
}
status = acpi_evaluate_integer(acpi_handle, "_STA", NULL, &sta);
if (ACPI_FAILURE(status))
- return;
+ return -EIO;
/* For now do not allow anything that looks like physical CPU HP */
if (cpu_present(cpu) && !(sta & ACPI_STA_DEVICE_PRESENT)) {
pr_err_once("Changing CPU present bit is not supported\n");
- return;
+ return -EOPNOTSUPP;
}
unregister_cpu(c);
+ return 0;
}
#endif /* CONFIG_ACPI_HOTPLUG_CPU */
diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
index 00775b91bd41..4361eed26d83 100644
--- a/drivers/acpi/acpi_processor.c
+++ b/drivers/acpi/acpi_processor.c
@@ -499,7 +499,15 @@ static void acpi_processor_post_eject(struct
acpi_device *device)
cpus_write_lock();
/* Remove the CPU. */
- arch_unregister_cpu(pr->id);
+ if (arch_unregister_cpu(pr->id)) {
+ cpus_write_unlock();
+ cpu_maps_update_done();
+ acpi_bind_one(pr->dev, device);
+ if (device_attach(pr->dev) < 0)
+ dev_err(pr->dev, "Processor driver could not be
attached\n");
+ return;
+ }
+
acpi_unmap_cpu(pr->id);
/* Clean up. */
diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c
index 875abdc9942e..57980d1c2931 100644
--- a/drivers/base/cpu.c
+++ b/drivers/base/cpu.c
@@ -570,9 +570,10 @@ int __weak arch_register_cpu(int cpu)
}
#ifdef CONFIG_HOTPLUG_CPU
-void __weak arch_unregister_cpu(int num)
+int __weak arch_unregister_cpu(int num)
{
unregister_cpu(&per_cpu(cpu_devices, num));
+ return 0;
}
#endif /* CONFIG_HOTPLUG_CPU */
#endif /* CONFIG_GENERIC_CPU_DEVICES */
diff --git a/include/linux/cpu.h b/include/linux/cpu.h
index 9b6b0d87fdb0..a7c191dea1fc 100644
--- a/include/linux/cpu.h
+++ b/include/linux/cpu.h
@@ -91,7 +91,7 @@ struct device *cpu_device_create(struct device
*parent, void *drvdata,
const char *fmt, ...);
extern bool arch_cpu_is_hotpluggable(int cpu);
extern int arch_register_cpu(int cpu);
-extern void arch_unregister_cpu(int cpu);
+extern int arch_unregister_cpu(int cpu);
#ifdef CONFIG_HOTPLUG_CPU
extern void unregister_cpu(struct cpu *cpu);
extern ssize_t arch_cpu_probe(const char *, size_t);
>
> Cheers,
>
> Will
>
^ permalink raw reply related
* Re: [PATCH v6 07/13] kho: add support for linked-block serialization
From: Mike Rapoport @ 2026-06-03 6:49 UTC (permalink / raw)
To: Pasha Tatashin
Cc: linux-kselftest, rppt, shuah, akpm, linux-mm, skhan, linux-doc,
linux-kernel, corbet, dmatlack, kexec, pratyush, skhawaja, graf
In-Reply-To: <20260603032905.344462-8-pasha.tatashin@soleen.com>
On Wed, 03 Jun 2026 03:28:58 +0000, Pasha Tatashin <pasha.tatashin@soleen.com> wrote:
> diff --git a/include/linux/kho/abi/block.h b/include/linux/kho/abi/block.h
> new file mode 100644
> index 000000000000..8641c20b379b
> --- /dev/null
> +++ b/include/linux/kho/abi/block.h
> @@ -0,0 +1,56 @@
> [ ... skip 25 lines ... ]
> +#define _LINUX_KHO_ABI_BLOCK_H
> +
> +#include <asm/page.h>
> +#include <linux/types.h>
> +
> +#define KHO_BLOCK_ABI_COMPATIBLE "kho-block-v1"
It's never used by block set and after looking at the following patches I
found that it's appended to LUO compatible string.
While this works for LUO, I think it should be kho_block_set_restore()
responsibility to verify the compatibility.
>
> diff --git a/kernel/liveupdate/kho_block.c b/kernel/liveupdate/kho_block.c
> new file mode 100644
> index 000000000000..4f147c308e6b
> --- /dev/null
> +++ b/kernel/liveupdate/kho_block.c
> @@ -0,0 +1,411 @@
> [ ... skip 121 lines ... ]
> +/**
> + * kho_block_set_grow - Expand the block set to accommodate the target count.
> + * @bs: The block set.
> + * @count: The target number of valid entries to accommodate.
> + *
> + * Acts as a runtime notifier when new resources (such as files or sessions)
Not sure I understand what "runtime notifier" means in this context.
> [ ... skip 11 lines ... ]
> +
> + while (count > bs->nblocks * bs->count_per_block) {
> + int err = kho_block_set_grow_one(bs);
> +
> + if (err)
> + return err;
This leaks memory if more than one block is added.
> [ ... skip 31 lines ... ]
> + * unregistered, allowing the block set to release and unallocate redundant
> + * preserved memory blocks. Checks if the last block in the set can be removed
> + * because the remaining entry count is fully accommodated by the preceding blocks.
> + *
> + * Note: It is the caller's responsibility to ensure that entries are removed
> + * in LIFO (last-in, first-out) order (the reverse order of their insertion).
I think "in LIFO order" is sufficient :)
> [ ... skip 173 lines ... ]
> + it->i = 0;
> + }
> +
> + entry = kho_block_entry(it, it->i++);
> + it->block->ser->count = it->i;
> + return entry;
This looks way better than the previous version :)
Thanks!
--
Sincerely yours,
Mike.
^ permalink raw reply
* Re: [PATCH v6 04/13] liveupdate: register luo_ser as KHO subtree
From: Mike Rapoport @ 2026-06-03 6:50 UTC (permalink / raw)
To: Pasha Tatashin
Cc: linux-kselftest, rppt, shuah, akpm, linux-mm, skhan, linux-doc,
linux-kernel, corbet, dmatlack, kexec, pratyush, skhawaja, graf
In-Reply-To: <20260603032905.344462-5-pasha.tatashin@soleen.com>
# Add your code comments below. There is no need to trim or delete
# any existing content -- just insert your comments under the relevant
# lines of code. Lines starting with "> " are quoted diff context and
# lines starting with "| " are comments from other reviewers.
# The final email will be reformatted automatically to include only
# the sections that have your comments.
#
> Entirely remove the LUO FDT wrapper since the FDT only carries the
> compatible string and the pointer to the centralized struct luo_ser.
> Instead, register the struct luo_ser via the KHO raw subtree
> API, placing the compatibility string inside the structure itself.
>
> Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
>
> diff --git a/include/linux/kho/abi/luo.h b/include/linux/kho/abi/luo.h
> index 1b2f865a771a..9a4fe491812b 100644
> --- a/include/linux/kho/abi/luo.h
> +++ b/include/linux/kho/abi/luo.h
> @@ -10,11 +10,11 @@
> *
> * Live Update Orchestrator uses the stable Application Binary Interface
> * defined below to pass state from a pre-update kernel to a post-update
> - * kernel. The ABI is built upon the Kexec HandOver framework and uses a
> - * Flattened Device Tree to describe the preserved data.
> + * kernel. The ABI is built upon the Kexec HandOver framework and registers
> + * the central `struct luo_ser` via the KHO raw subtree API.
> *
> - * This interface is a contract. Any modification to the FDT structure, node
> - * properties, compatible strings, or the layout of the `__packed` serialization
> + * This interface is a contract. Any modification to the structure fields,
> + * compatible strings, or the layout of the `__packed` serialization
> * structures defined here constitutes a breaking change. Such changes require
> * incrementing the version number in the relevant `_COMPATIBLE` string to
> * prevent a new kernel from misinterpreting data from an old kernel.
> @@ -23,31 +23,15 @@
> * however, backward/forward compatibility is only guaranteed for kernels
> * supporting the same ABI version.
> *
> - * FDT Structure Overview:
> + * KHO Structure Overview:
> * The entire LUO state is encapsulated within a single KHO entry named "LUO".
> - * This entry contains an FDT with the following layout:
> - *
> - * .. code-block:: none
> - *
> - * / {
> - * compatible = "luo-v2";
> - * luo-abi-header = <phys_addr_of_luo_ser>;
> - * };
> - *
> - * Main LUO Node (/):
> - *
> - * - compatible: "luo-v2"
> - * Identifies the overall LUO ABI version.
> - * - luo-abi-header: u64
> - * The physical address of `struct luo_ser`.
> + * This entry contains the `struct luo_ser` structure.
> *
> * Serialization Structures:
> - * The FDT properties point to memory regions containing arrays of simple,
> - * `__packed` structures. These structures contain the actual preserved state.
> - *
> * - struct luo_ser:
> * The central ABI structure that contains the overall state of the LUO.
> - * It includes the liveupdate-number and pointers to sessions and FLBs.
> + * It includes the compatibility string, the liveupdate-number, and pointers
> + * to sessions and FLBs.
> *
> * - struct luo_session_header_ser:
> * Header for the session array. Contains the total page count of the
> @@ -78,26 +62,27 @@
> #ifndef _LINUX_KHO_ABI_LUO_H
> #define _LINUX_KHO_ABI_LUO_H
>
> +#include <linux/align.h>
> #include <uapi/linux/liveupdate.h>
>
> /*
> - * The LUO FDT hooks all LUO state for sessions, fds, etc.
> + * The LUO state is registered under this KHO entry name.
> */
> -#define LUO_FDT_SIZE PAGE_SIZE
> -#define LUO_FDT_KHO_ENTRY_NAME "LUO"
> -#define LUO_FDT_COMPATIBLE "luo-v2"
> -#define LUO_FDT_ABI_HEADER "luo-abi-header"
> +#define LUO_KHO_ENTRY_NAME "LUO"
> +#define LUO_ABI_COMPATIBLE "luo-v3"
> +#define LUO_ABI_COMPAT_LEN ALIGN(sizeof(LUO_ABI_COMPATIBLE), 8)
>
> /**
> * struct luo_ser - Centralized LUO ABI header.
> + * @compatible: Compatibility string identifying the LUO ABI version.
> * @liveupdate_num: A counter tracking the number of successful live updates.
> * @sessions_pa: Physical address of the first session block header.
> * @flbs_pa: Physical address of the FLB header.
> *
> - * This structure is the root of all preserved LUO state. It is pointed to by
> - * the "luo-abi-header" property in the LUO FDT.
> + * This structure is the root of all preserved LUO state.
> */
> struct luo_ser {
> + char compatible[LUO_ABI_COMPAT_LEN];
> u64 liveupdate_num;
> u64 sessions_pa;
> u64 flbs_pa;
> @@ -111,7 +96,7 @@ struct luo_ser {
> * @data: Private data
> * @token: User provided token for this file
> *
> - * If this structure is modified, LUO_SESSION_COMPATIBLE must be updated.
> + * If this structure is modified, `LUO_ABI_COMPATIBLE` must be updated.
> */
> struct luo_file_ser {
> char compatible[LIVEUPDATE_HNDL_COMPAT_LENGTH];
> @@ -142,7 +127,7 @@ struct luo_file_set_ser {
> * physical memory preserved across the kexec. It provides the necessary
> * metadata to interpret the array of session entries that follow.
> *
> - * If this structure is modified, `LUO_FDT_COMPATIBLE` must be updated.
> + * If this structure is modified, `LUO_ABI_COMPATIBLE` must be updated.
> */
> struct luo_session_header_ser {
> u64 count;
> @@ -159,7 +144,7 @@ struct luo_session_header_ser {
> * session) is created and passed to the new kernel, allowing it to reconstruct
> * the session context.
> *
> - * If this structure is modified, `LUO_FDT_COMPATIBLE` must be updated.
> + * If this structure is modified, `LUO_ABI_COMPATIBLE` must be updated.
> */
> struct luo_session_ser {
> char name[LIVEUPDATE_SESSION_NAME_LENGTH];
> @@ -180,7 +165,7 @@ struct luo_session_ser {
> * This structure is located at the physical address specified by the
> * flbs_pa in luo_ser.
> *
> - * If this structure is modified, `LUO_FDT_COMPATIBLE` must be updated.
> + * If this structure is modified, `LUO_ABI_COMPATIBLE` must be updated.
> */
> struct luo_flb_header_ser {
> u64 pgcnt;
> @@ -202,7 +187,7 @@ struct luo_flb_header_ser {
> * passed to the new kernel. Each entry allows the LUO core to restore one
> * global, shared object.
> *
> - * If this structure is modified, `LUO_FDT_COMPATIBLE` must be updated.
> + * If this structure is modified, `LUO_ABI_COMPATIBLE` must be updated.
> */
> struct luo_flb_ser {
> char name[LIVEUPDATE_FLB_COMPAT_LENGTH];
> diff --git a/kernel/liveupdate/luo_core.c b/kernel/liveupdate/luo_core.c
> index fbc18c5f4230..e261a03a1b47 100644
> --- a/kernel/liveupdate/luo_core.c
> +++ b/kernel/liveupdate/luo_core.c
> @@ -50,7 +50,6 @@
> #include <linux/kexec_handover.h>
> #include <linux/kho/abi/luo.h>
> #include <linux/kobject.h>
> -#include <linux/libfdt.h>
> #include <linux/liveupdate.h>
> #include <linux/miscdevice.h>
> #include <linux/mm.h>
> @@ -63,8 +62,7 @@
>
> static struct {
> bool enabled;
> - void *fdt_out;
> - void *fdt_in;
> + struct luo_ser *luo_ser_out;
> u64 liveupdate_num;
> } luo_global;
>
> @@ -81,11 +79,10 @@ early_param("liveupdate", early_liveupdate_param);
>
> static int __init luo_early_startup(void)
> {
> + phys_addr_t luo_ser_phys;
> struct luo_ser *luo_ser;
> - int err, header_size;
> - phys_addr_t fdt_phys;
> - const void *ptr;
> - u64 luo_ser_pa;
> + size_t len;
> + int err;
>
> if (!kho_is_enabled()) {
> if (liveupdate_enabled())
> @@ -94,40 +91,29 @@ static int __init luo_early_startup(void)
> return 0;
> }
>
> - /* Retrieve LUO subtree, and verify its format. */
> - err = kho_retrieve_subtree(LUO_FDT_KHO_ENTRY_NAME, &fdt_phys, NULL);
> + /* Retrieve LUO state from KHO. */
> + err = kho_retrieve_subtree(LUO_KHO_ENTRY_NAME, &luo_ser_phys, &len);
> if (err) {
> if (err != -ENOENT) {
> - pr_err("failed to retrieve FDT '%s' from KHO: %pe\n",
> - LUO_FDT_KHO_ENTRY_NAME, ERR_PTR(err));
> + pr_err("failed to retrieve LUO state '%s' from KHO: %pe\n",
> + LUO_KHO_ENTRY_NAME, ERR_PTR(err));
> return err;
> }
>
> return 0;
> }
>
> - luo_global.fdt_in = phys_to_virt(fdt_phys);
> - err = fdt_node_check_compatible(luo_global.fdt_in, 0,
> - LUO_FDT_COMPATIBLE);
> - if (err) {
> - pr_err("FDT '%s' is incompatible with '%s' [%d]\n",
> - LUO_FDT_KHO_ENTRY_NAME, LUO_FDT_COMPATIBLE, err);
> -
> + if (len < sizeof(*luo_ser)) {
> + pr_err("LUO state is too small (%zu < %zu)\n", len, sizeof(*luo_ser));
> return -EINVAL;
> }
>
> - header_size = 0;
> - ptr = fdt_getprop(luo_global.fdt_in, 0, LUO_FDT_ABI_HEADER, &header_size);
> - if (!ptr || header_size != sizeof(u64)) {
> - pr_err("Unable to get ABI header '%s' [%d]\n",
> - LUO_FDT_ABI_HEADER, header_size);
> -
> + luo_ser = phys_to_virt(luo_ser_phys);
> + if (strncmp(luo_ser->compatible, LUO_ABI_COMPATIBLE, LUO_ABI_COMPAT_LEN)) {
> + pr_err("LUO state is incompatible with '%s'\n", LUO_ABI_COMPATIBLE);
> return -EINVAL;
> }
>
> - luo_ser_pa = get_unaligned((u64 *)ptr);
> - luo_ser = phys_to_virt(luo_ser_pa);
> -
> luo_global.liveupdate_num = luo_ser->liveupdate_num;
> pr_info("Retrieved live update data, liveupdate number: %lld\n",
> luo_global.liveupdate_num);
> @@ -160,37 +146,20 @@ static int __init liveupdate_early_init(void)
> }
> early_initcall(liveupdate_early_init);
>
> -/* Called during boot to create outgoing LUO fdt tree */
> -static int __init luo_fdt_setup(void)
> +/* Called during boot to create outgoing LUO state */
> +static int __init luo_state_setup(void)
> {
> struct luo_ser *luo_ser;
> - u64 luo_ser_pa;
> - void *fdt_out;
> int err;
>
> - fdt_out = kho_alloc_preserve(LUO_FDT_SIZE);
> - if (IS_ERR(fdt_out)) {
> - pr_err("failed to allocate/preserve FDT memory\n");
> - return PTR_ERR(fdt_out);
> - }
> -
> luo_ser = kho_alloc_preserve(sizeof(*luo_ser));
> if (IS_ERR(luo_ser)) {
> - err = PTR_ERR(luo_ser);
> - goto exit_free_fdt;
> + pr_err("failed to allocate/preserve LUO state memory\n");
> + return PTR_ERR(luo_ser);
> }
> - luo_ser_pa = virt_to_phys(luo_ser);
> -
> - err = fdt_create(fdt_out, LUO_FDT_SIZE);
> - err |= fdt_finish_reservemap(fdt_out);
> - err |= fdt_begin_node(fdt_out, "");
> - err |= fdt_property_string(fdt_out, "compatible", LUO_FDT_COMPATIBLE);
> - err |= fdt_property(fdt_out, LUO_FDT_ABI_HEADER, &luo_ser_pa,
> - sizeof(luo_ser_pa));
> - err |= fdt_end_node(fdt_out);
> - err |= fdt_finish(fdt_out);
> - if (err)
> - goto exit_free_luo_ser;
> +
> + strscpy(luo_ser->compatible, LUO_ABI_COMPATIBLE, sizeof(luo_ser->compatible));
> + luo_ser->liveupdate_num = luo_global.liveupdate_num + 1;
>
> err = luo_session_setup_outgoing(&luo_ser->sessions_pa);
> if (err)
> @@ -200,21 +169,17 @@ static int __init luo_fdt_setup(void)
> if (err)
> goto exit_free_luo_ser;
>
> - luo_ser->liveupdate_num = luo_global.liveupdate_num + 1;
> -
> - err = kho_add_subtree(LUO_FDT_KHO_ENTRY_NAME, fdt_out,
> - fdt_totalsize(fdt_out));
> + err = kho_add_subtree(LUO_KHO_ENTRY_NAME, luo_ser, sizeof(*luo_ser));
> if (err)
> goto exit_free_luo_ser;
> - luo_global.fdt_out = fdt_out;
> +
> + luo_global.luo_ser_out = luo_ser;
>
> return 0;
>
> exit_free_luo_ser:
> kho_unpreserve_free(luo_ser);
> -exit_free_fdt:
> - kho_unpreserve_free(fdt_out);
> - pr_err("failed to prepare LUO FDT: %d\n", err);
> + pr_err("failed to prepare LUO state: %d\n", err);
>
> return err;
> }
> @@ -230,7 +195,7 @@ static int __init luo_late_startup(void)
> if (!liveupdate_enabled())
> return 0;
>
> - err = luo_fdt_setup();
> + err = luo_state_setup();
> if (err)
> luo_global.enabled = false;
>
--
Sincerely yours,
Mike.
^ permalink raw reply
* Re: [PATCH v6 02/13] liveupdate: avoid mixing cleanup guards with goto in luo_session_retrieve_fd
From: Mike Rapoport @ 2026-06-03 6:52 UTC (permalink / raw)
To: Pasha Tatashin
Cc: linux-kselftest, rppt, shuah, akpm, linux-mm, skhan, linux-doc,
linux-kernel, corbet, dmatlack, kexec, pratyush, skhawaja, graf
In-Reply-To: <20260603032905.344462-3-pasha.tatashin@soleen.com>
On Wed, 03 Jun 2026 03:28:53 +0000, Pasha Tatashin <pasha.tatashin@soleen.com> wrote:
> Refactoring luo_session_retrieve_fd() to avoid mixing automated
> cleanup-style guards with goto-based resource release, which is not
> recommended under the Linux kernel coding style.
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
--
Sincerely yours,
Mike.
^ permalink raw reply
* Re: [PATCH v6 03/13] liveupdate: centralize state management into struct luo_ser
From: Mike Rapoport @ 2026-06-03 6:52 UTC (permalink / raw)
To: Pasha Tatashin
Cc: linux-kselftest, rppt, shuah, akpm, linux-mm, skhan, linux-doc,
linux-kernel, corbet, dmatlack, kexec, pratyush, skhawaja, graf
In-Reply-To: <20260603032905.344462-4-pasha.tatashin@soleen.com>
On Wed, 03 Jun 2026 03:28:54 +0000, Pasha Tatashin <pasha.tatashin@soleen.com> wrote:
> Transition the LUO to ABI v2, which centralizes state management into a
> single struct luo_ser header.
>
> Previously, LUO state was spread across multiple FDT properties and
> subnodes. ABI v2 simplifies this by placing all core state, including
> the liveupdate number and physical addresses for sessions and FLB
> headers into a centralized struct luo_ser.
>
> [...]
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
--
Sincerely yours,
Mike.
^ permalink raw reply
* Re: [PATCH v3 3/4] cpufreq: Remove driver default policy->min/max init
From: Pierre Gondois @ 2026-06-03 7:48 UTC (permalink / raw)
To: Rafael J. Wysocki
Cc: linux-kernel, Jie Zhan, Lifeng Zheng, Ionela Voinescu,
Sumit Gupta, Zhongqiu Han, Viresh Kumar, Jonathan Corbet,
Shuah Khan, Huang Rui, Mario Limonciello, Perry Yuan,
K Prateek Nayak, Srinivas Pandruvada, Len Brown, Saravana Kannan,
linux-pm, linux-doc
In-Reply-To: <CAJZ5v0hwYcvYZJ1jCSo_5vpynOLBciW-4-KeracQTyUCw7fSGw@mail.gmail.com>
Hello Rafael,
On 6/1/26 20:08, Rafael J. Wysocki wrote:
> On Thu, May 28, 2026 at 11:10 AM Pierre Gondois <pierre.gondois@arm.com> wrote:
>> Prior to [1], drivers were setting policy->min/max and
>> the value was used as a QoS constraint. After that change,
>> the values were only temporarily used: cpufreq_set_policy()
>> ultimately overriding them through:
>> cpufreq_policy_online()
>> \-cpufreq_init_policy()
>> \-cpufreq_set_policy()
>> \-/* Set policy->min/max */
>>
>> This patch reinstate the initial behaviour. This will allow
>> drivers to request min/max QoS frequencies if desired.
>> For instance, the cppc driver advertises a lowest non-linear
>> frequency, which should be used as a min QoS value.
>>
>> To avoid having drivers setting policy->min/max to default
>> values which are considered as QoS values (i.e. the reason
>> why [1] was introduced), remove the initialization of
>> policy->min/max in .init() callbacks wherever the
>> policy->min/max values are identical to the
>> policy->cpuinfo.min/max_freq.
>>
>> Indeed, the previous patch ("cpufreq: Set default
>> policy->min/max values for all drivers") makes this initialization
>> redundant.
>>
>> The only drivers where these values are different are:
>> - gx-suspmod.c (min)
>> - cppc-cpufreq.c (min)
>> - longrun.c
>>
>> [1]
>> commit 521223d8b3ec ("cpufreq: Fix initialization of min and
>> max frequency QoS requests")
>>
>> Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
>> Acked-by: Jie Zhan <zhanjie9@hisilicon.com>
> sashiko.dev has some feedback on this patch and appears to have a point:
>
> https://sashiko.dev/#/patchset/20260528090913.2759118-1-pierre.gondois%40arm.com
>
> Can you have a look at it please?
>
[sashiko]
> Does removing the policy->max = max_freq assignment here break UAPI
> expectations by exposing the unlisted boost frequency in
scaling_max_freq?
>
> Commit 538b0188da4653 intentionally allowed drivers like acpi-cpufreq
to set
> policy->cpuinfo.max_freq to a higher boost frequency while relying on
> cpufreq_frequency_table_cpuinfo() to clamp policy->max to the frequency
> table's nominal maximum (max_freq). This ensured that user-space
tools saw
> the nominal maximum in scaling_max_freq.
>
> Although commit 521223d8b3ec temporarily disrupted this by defaulting
the QoS
> max to -1, a subsequent patch in this series changes the core to
initialize
> the QoS request using policy->max.
Effectively PATCH [4/4] cpufreq: Use policy->min/max init as QoS request
now uses the policy->max value set by the .init() callback to set
the max_freq_req QoS constraint.
>
> If the policy->max = max_freq assignment were preserved, the subsequent
> patch would successfully use the nominal frequency as the QoS max
request,
> restoring the correct clamping behavior.
IIUC this suggests to use the nominal freq. as the QoS max request.
This was behaving like that prior to 521223d8b3ec. However doing
that would mean that if boost is enabled and the max_freq_req sysfs
is not updated, then the frequency would still be clamped by
the max_freq_req. 521223d8b3ec intended to correct that.
Sashiko seems to suggest modifications to come back to the
pre-521223d8b3ec behaviour, but I think 521223d8b3ec is correct
and we should conserve this behaviour.
>
> However, since this patch explicitly deletes the policy->max = max_freq
> assignment, policy->max remains 0, causing the subsequent patch to
fall back
> to the default -1. The core then resolves -1 to cpuinfo.max_freq (the
boost
> frequency) and permanently overwrites policy->max.
^ permalink raw reply
* Re: [PATCH mm-unstable v18 11/14] mm/khugepaged: Introduce mTHP collapse support
From: David Hildenbrand (Arm) @ 2026-06-03 8:05 UTC (permalink / raw)
To: Lance Yang, Nico Pache
Cc: linux-doc, linux-kernel, linux-mm, linux-trace-kernel, aarcange,
akpm, anshuman.khandual, apopple, baohua, baolin.wang, byungchul,
catalin.marinas, cl, corbet, dave.hansen, dev.jain, gourry,
hannes, hughd, jack, jackmanb, jannh, jglisse, joshua.hahnjy, kas,
liam, ljs, mathieu.desnoyers, matthew.brost, mhiramat, mhocko,
peterx, pfalcato, rakie.kim, raquini, rdunlap, richard.weiyang,
rientjes, rostedt, rppt, ryan.roberts, shivankg, sunnanyong,
surenb, thomas.hellstrom, tiwai, usamaarif642, vbabka,
vishal.moola, wangkefeng.wang, will, willy, yang, ying.huang, ziy,
zokeefe
In-Reply-To: <185f5699-3797-4300-8c54-bb99fc2a45e0@linux.dev>
On 6/2/26 17:44, Lance Yang wrote:
>
>
> On 2026/6/2 18:58, Nico Pache wrote:
>> On Sun, May 31, 2026 at 1:19 AM Lance Yang <lance.yang@linux.dev> wrote:
>>>
>>>
>>> [...]
>>>
>>> Hmm ... don't we lose the allocation-failure result here?
>>>
>>> Previously collapse_scan_pmd() propagated SCAN_ALLOC_HUGE_PAGE_FAIL from
>>> collapse_huge_page(), so khugepaged would call khugepaged_alloc_sleep()
>>> in khugepaged_do_scan().
>>>
>>> Now if allocation fails and nr_collapsed stays 0, we just return
>>> SCAN_FAIL. So we won't back off via khugepaged_alloc_sleep() anymore?
>>
>> Ok I did the error propagation! I think I handled both of these cases
>> you brought up pretty easily.
>
> Thanks.
>
>> However I don't know what to do in the following case: We successfully
>> collapsed some portion of the PMD, but during that process, we also
>> hit an allocation failure. Is it best to back off entirely? or can we
>> treat some forward progress as a sign we can continue trying collapses
>> without sleeping.
>>
>> Basically, do we prioritize SCAN_ALLOC_HUGE_PAGE_FAIL or the
>> successful collapses as the returned value?
>
> Thinking out loud, forward progress should win here, the allocation
> failure only matter if we made no progress at all?
Agreed, in the first approach, forward progress makes sense.
--
Cheers,
David
^ permalink raw reply
* [PATCH] Documentation: index.rst: add entry of other sub-directory
From: Manuel Ebner @ 2026-06-03 8:04 UTC (permalink / raw)
To: Sebastian Andrzej Siewior, Clark Williams, Steven Rostedt,
Jonathan Corbet, Shuah Khan,
open list:Real-time Linux (PREEMPT_RT), open list:DOCUMENTATION,
open list
Cc: Manuel Ebner
add reference to scheduler/sched-rt-group.rst
Signed-off-by: Manuel Ebner <manuelebner@mailbox.org>
---
Documentation/core-api/real-time/index.rst | 1 +
1 file changed, 1 insertion(+)
diff --git a/Documentation/core-api/real-time/index.rst b/Documentation/core-api/real-time/index.rst
index f08d2395a22c..661b419e7f8f 100644
--- a/Documentation/core-api/real-time/index.rst
+++ b/Documentation/core-api/real-time/index.rst
@@ -15,3 +15,4 @@ the required changes compared to a non-PREEMPT_RT configuration.
differences
hardware
architecture-porting
+ Real-Time group scheduling <../../scheduler/sched-rt-group>
--
2.54.0
^ permalink raw reply related
* Re: [PATCH v15 03/12] lib: kstrtox: add kstrtoudec64() and kstrtodec64()
From: Rodrigo Alencar @ 2026-06-03 8:13 UTC (permalink / raw)
To: Andy Shevchenko, rodrigo.alencar
Cc: linux-kernel, linux-iio, devicetree, linux-doc, Jonathan Cameron,
David Lechner, Andy Shevchenko, Lars-Peter Clausen,
Michael Hennerich, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
Jonathan Corbet, Andrew Morton, Petr Mladek, Steven Rostedt,
Rasmus Villemoes, Sergey Senozhatsky, Shuah Khan
In-Reply-To: <ah9EXNnutqk1FoV2@ashevche-desk.local>
On 26/06/03 12:00AM, Andy Shevchenko wrote:
> On Sun, May 31, 2026 at 09:30:46AM +0100, Rodrigo Alencar via B4 Relay wrote:
> >
> > Add helpers that parses decimal numbers into 64-bit number, i.e., decimal
> > point numbers with pre-defined scale are parsed into a 64-bit value (fixed
> > precision). After the decimal point, digits beyond the specified scale
> > are ignored.
>
> ...
>
> > +static int _kstrtoudec64(const char *s, unsigned int scale, u64 *res)
> > +{
> > + u64 _res = 0;
> > + unsigned int rv_int, rv_frac;
> > +
> > + rv_int = _parse_integer(s, 10, &_res);
> > + if (rv_int & KSTRTOX_OVERFLOW)
> > + return -ERANGE;
> > + s += rv_int;
> > +
> > + if (*s == '.')
> > + s++; /* skip decimal point */
> > +
> > + rv_frac = _parse_integer_limit_init(s, 10, _res, &_res, scale);
> > + if (rv_frac & KSTRTOX_OVERFLOW)
> > + return -ERANGE;
> > + s += rv_frac;
>
> > + if (!rv_int && !rv_frac && !isdigit(*s))
>
> Do we care about isdigit() here? Why?
The check here validates the presence of digits, and
this is to cover a corner case with scale = 0 and s = ".5",
which is considered a valid input and leads to rv_int = 0 and
rv_frac = 0, outputing res = 0
--
Kind regards,
Rodrigo Alencar
^ permalink raw reply
* [PATCH v2] docs: zh_TW: process: localize terminologies and improve fluency in 8.Conclusion
From: Chen-Yu Yeh @ 2026-06-03 8:25 UTC (permalink / raw)
To: Hu Haowen
Cc: Jonathan Corbet, Shuah Khan, Dongliang Mu, linux-doc,
linux-kernel, Chen-Yu Yeh, Dongliang Mu
Translate PRC tech terms into Taiwanese tech terms (e.g.,
內核 -> 核心, 代碼 -> 程式碼, 軟件 -> 軟體) to improve
readability for local developers. Also, rephrase several
awkward sentences to make the document more fluent.
Reviewed-by: Dongliang Mu <dzm91@hust.edu.cn>
Signed-off-by: Chen-Yu Yeh <chenyou910331@gmail.com>
---
Changes in v2:
- Update Signed-off-by to use full real name.
- Add Reviewed-by tag from Dongliang Mu.
.../zh_TW/process/8.Conclusion.rst | 45 +++++++++----------
1 file changed, 22 insertions(+), 23 deletions(-)
diff --git a/Documentation/translations/zh_TW/process/8.Conclusion.rst b/Documentation/translations/zh_TW/process/8.Conclusion.rst
index d1634421b62c..823969cf793d 100644
--- a/Documentation/translations/zh_TW/process/8.Conclusion.rst
+++ b/Documentation/translations/zh_TW/process/8.Conclusion.rst
@@ -14,42 +14,41 @@
.. _tw_development_conclusion:
-更多信息
+更多資訊
========
-關於Linux內核開發和相關主題的信息來源很多。首先是在內核源代碼分發中找到的
-文檔目錄。頂級
+關於Linux核心開發和相關主題的資訊來源很多。首先是在核心原始碼分發中找到的
+文件目錄。頂級
:ref:`Documentation/translations/zh_CN/process/howto.rst <tw_process_howto>`
文件是一個重要的起點；
:ref:`Documentation/translations/zh_CN/process/submitting-patches.rst <tw_submittingpatches>`
-也是所有內核開發人員都應該閱讀的內容。許多內部內核API都是使用kerneldoc機制
-記錄的；“make htmldocs”或“make pdfdocs”可用於以HTML或PDF格式生成這些文檔
-（儘管某些發行版提供的tex版本會遇到內部限制，無法正確處理文檔）。
-
-不同的網站在各個細節層次上討論內核開發。本文作者想謙虛地建議用 https://lwn.net/
-作爲來源；有關許多特定內核主題的信息可以通過以下網址的 LWN 內核索引找到：
+也是所有核心開發人員都應該閱讀的內容。許多內部核心API都是使用kerneldoc機制
+記錄的；“make htmldocs”或“make pdfdocs”可用於以HTML或PDF格式生成這些文件
+（儘管某些發行版提供的tex版本會遇到內部限制，無法正確處理文件）。
+不同的網站在各個細節層次上討論核心開發。本文作者想謙虛地建議用 https://lwn.net/
+作爲來源；有關許多特定核心主題的資訊可以通過以下網址的 LWN 核心索引找到:
http://lwn.net/kernel/index/
-除此之外，內核開發人員的一個寶貴資源是：
+除此之外，核心開發人員的一個寶貴資源是：
https://kernelnewbies.org/
-當然，也不應該忘記 https://kernel.org/ ，這是內核發佈信息的最終位置。
+當然，也不應該忘記 https://kernel.org/ ，這是核心發佈資訊的最終位置。
-關於內核開發有很多書：
+關於核心開發有很多書：
《Linux設備驅動程序》第三版（Jonathan Corbet、Alessandro Rubini和Greg Kroah Hartman）
線上版本在 http://lwn.net/kernel/ldd3/
- 《Linux內核設計與實現》（Robert Love）
+ 《Linux核心設計與實現》（Robert Love）
- 《深入理解Linux內核》(Daniel Bovet和Marco Cesati）
+ 《深入理解Linux核心》(Daniel Bovet和Marco Cesati）
然而，所有這些書都有一個共同的缺點：它們上架時就往往有些過時，而且已經上架
-一段時間了。不過，在那裏還是可以找到相當多的好信息。
+一段時間了。不過，在那裏還是可以找到相當多的好資訊。
-有關git的文檔，請訪問：
+有關git的文件，請訪問：
https://www.kernel.org/pub/software/scm/git/docs/
@@ -58,16 +57,16 @@
結論
====
-祝賀所有通過這篇冗長的文檔的人。希望它能夠幫助您理解Linux內核是如何開發的，
+祝賀所有通過這篇冗長的文件的人。希望它能夠幫助您理解Linux核心是如何開發的，
以及您如何參與這個過程。
-最後，重要的是參與。任何開源軟件項目都不會超過其貢獻者投入其中的總和。Linux
-內核的發展速度和以前一樣快，因爲它得到了大量開發人員的幫助，他們都在努力使它
-變得更好。內核是一個最成功的例子，說明了當成千上萬的人爲了一個共同的目標一起
+最後，重要的是參與。任何開源軟體專案都不會超過其貢獻者投入其中的總和。Linux
+核心的發展速度和以前一樣快，因爲它得到了大量開發人員的幫助，他們都在努力使它
+變得更好。核心是一個最成功的例子，說明了當成千上萬的人爲了一個共同的目標一起
工作時，可以做出什麼。
-不過，內核總是可以從更大的開發人員基礎中獲益。總有更多的工作要做。但是同樣
-重要的是，Linux生態系統中的大多數其他參與者可以通過爲內核做出貢獻而受益。使
-代碼進入主線是提高代碼質量、降低維護和分發成本、提高對內核開發方向的影響程度
+不過，核心總是可以從更大的開發人員基礎中獲益。總有更多的工作要做。但是同樣
+重要的是，Linux生態系統中的大多數其他參與者可以通過爲核心做出貢獻而受益。使
+程式碼進入主線是提高程式碼品質、降低維護和分發成本、提高對核心開發方向的影響程度
等的關鍵。這是一種共贏的局面。啓動你的編輯器，來加入我們吧；你會非常受歡迎的。
--
2.43.0
^ permalink raw reply related
* Re: [PATCH v15 03/12] lib: kstrtox: add kstrtoudec64() and kstrtodec64()
From: Andy Shevchenko @ 2026-06-03 8:30 UTC (permalink / raw)
To: Rodrigo Alencar
Cc: rodrigo.alencar, linux-kernel, linux-iio, devicetree, linux-doc,
Jonathan Cameron, David Lechner, Andy Shevchenko,
Lars-Peter Clausen, Michael Hennerich, Rob Herring,
Krzysztof Kozlowski, Conor Dooley, Jonathan Corbet, Andrew Morton,
Petr Mladek, Steven Rostedt, Rasmus Villemoes, Sergey Senozhatsky,
Shuah Khan
In-Reply-To: <etbgk2eap5w2db36kqoze7qehp2jmydc5a7stfymqowsqukf45@g2w4zew2zhic>
On Wed, Jun 03, 2026 at 09:13:40AM +0100, Rodrigo Alencar wrote:
> On 26/06/03 12:00AM, Andy Shevchenko wrote:
> > On Sun, May 31, 2026 at 09:30:46AM +0100, Rodrigo Alencar via B4 Relay wrote:
...
> > > +static int _kstrtoudec64(const char *s, unsigned int scale, u64 *res)
> > > +{
> > > + u64 _res = 0;
> > > + unsigned int rv_int, rv_frac;
> > > +
> > > + rv_int = _parse_integer(s, 10, &_res);
> > > + if (rv_int & KSTRTOX_OVERFLOW)
> > > + return -ERANGE;
> > > + s += rv_int;
> > > +
> > > + if (*s == '.')
> > > + s++; /* skip decimal point */
> > > +
> > > + rv_frac = _parse_integer_limit_init(s, 10, _res, &_res, scale);
> > > + if (rv_frac & KSTRTOX_OVERFLOW)
> > > + return -ERANGE;
> > > + s += rv_frac;
> >
> > > + if (!rv_int && !rv_frac && !isdigit(*s))
> >
> > Do we care about isdigit() here? Why?
>
> The check here validates the presence of digits, and
> this is to cover a corner case with scale = 0 and s = ".5",
> which is considered a valid input and leads to rv_int = 0 and
> rv_frac = 0, outputing res = 0
Please, add a comment on top of this check.
--
With Best Regards,
Andy Shevchenko
^ permalink raw reply
* Re: [PATCH 02/15] accel/qda: Add QDA driver documentation
From: Tomeu Vizoso @ 2026-06-03 8:54 UTC (permalink / raw)
To: Ekansh Gupta
Cc: Dmitry Baryshkov, Oded Gabbay, Jonathan Corbet, Shuah Khan,
Joerg Roedel, Will Deacon, Robin Murphy, Maarten Lankhorst,
Maxime Ripard, Thomas Zimmermann, David Airlie, Simona Vetter,
Sumit Semwal, Christian König, Bharath Kumar,
Chenna Kesava Raju, srini, andersson, konradybcio, robin.clark,
linux-kernel, dri-devel, linux-doc, linux-arm-msm, iommu,
linux-media, linaro-mm-sig
In-Reply-To: <9879f670-8a23-407b-ab45-673904ad4a86@oss.qualcomm.com>
On Wed, Jun 3, 2026 at 7:22 AM Ekansh Gupta
<ekansh.gupta@oss.qualcomm.com> wrote:
>
> On 20-05-2026 21:17, Tomeu Vizoso wrote:
> > On Wed, May 20, 2026 at 4:12 PM Dmitry Baryshkov
> > <dmitry.baryshkov@oss.qualcomm.com> wrote:
> >>
> >> On Tue, May 19, 2026 at 11:45:52AM +0530, Ekansh Gupta via B4 Relay wrote:
> >>> From: Ekansh Gupta <ekansh.gupta@oss.qualcomm.com>
> >>>
> >>> Add documentation for the Qualcomm DSP Accelerator (QDA) driver under
> >>> Documentation/accel/qda/. The documentation covers the driver
> >>> architecture, GEM-based buffer management, IOMMU context bank
> >>> isolation, and the RPMsg transport layer.
> >>>
> >>> The user-space API section describes the DRM IOCTLs for session
> >>> management, GEM buffer allocation, and remote procedure invocation via
> >>> the FastRPC protocol, along with a typical application lifecycle
> >>> example. Sections for dynamic debug and basic testing are also
> >>> included.
> >>>
> >>> Wire the new documentation into the Compute Accelerators index at
> >>> Documentation/accel/index.rst.
> >>>
> >>> Assisted-by: Claude:claude-4-6-sonnet
> >>> Signed-off-by: Ekansh Gupta <ekansh.gupta@oss.qualcomm.com>
> >>> ---
> >>> Documentation/accel/index.rst | 1 +
> >>> Documentation/accel/qda/index.rst | 13 ++++
> >>> Documentation/accel/qda/qda.rst | 146 ++++++++++++++++++++++++++++++++++++++
> >>> 3 files changed, 160 insertions(+)
<snip>
> >>> +Usage Example
> >>> +=============
> >>> +
> >>> +A typical lifecycle for a user-space application:
> >>> +
> >>> +1. **Discovery**: Open ``/dev/accel/accel*`` and use
> >>> + ``DRM_IOCTL_QDA_QUERY`` to identify the DSP domain served by that
> >>> + device node.
> >>> +2. **Initialization**: Call ``DRM_IOCTL_QDA_REMOTE_SESSION_CREATE`` to
> >>> + establish a session and create a process context on the DSP.
> >>> +3. **Memory**: Allocate buffers via ``DRM_IOCTL_QDA_GEM_CREATE`` or import
> >>> + DMA-BUFs (PRIME fd) from other drivers using ``DRM_IOCTL_PRIME_FD_TO_HANDLE``.
> >>> +4. **Execution**: Use ``DRM_IOCTL_QDA_REMOTE_INVOKE`` to pass arguments and
> >>> + execute functions on the DSP.
> >>> +5. **Cleanup**: Close file descriptors to automatically release resources and
> >>> + detach the session.
> >>
> >> I'd have expected the description of the actual example. I.e. clone the
> >> app from https://the.addr, prepare clang >= NN.MM, QAIC (https://foo),
> >> run make, run the app, check the results. I'd remind that DRM Accel has
> >> a very specific requirement of having the working toolhain in the
> >> open-source.
> >
> > We have been getting submissions lately that don't fulfill that
> > requirement so I will point to the precise part of the documentation
> > that explains it:
> >
> > https://www.kernel.org/doc/html/latest/gpu/drm-uapi.html#open-source-userspace-requirements
> >
> > For an example of a submissions that complies, see:
> >
> > https://lore.kernel.org/dri-devel/20260114-thames-v2-0-e94a6636e050@tomeuvizoso.net/
> >
> > Most importantly, notice how the proposed Thames Mesa driver generates
> > machine code for all the hardware units, and doesn't use any blob for
> > that.
> >
> I believe QDA checks all boxes for accel, as there is available
> opensource userspace, opensource QAIC compiler for IDL compilation and
> LLVM supports hexagon arch.
I must say that I'm at a total loss regarding the userspace portion of
this driver, despite spending half an hour looking inside the FastRPC
branch that you link from the cover letter.
Can you please explain what do people need to do to:
- run an algorithm of their choice on the DSP,
- execute inference with a common ML framework such as TensorFlow Lite
or PyTorch.
The documentation I pointed to earlier explains in length what is
expected from the userspace portion of the driver, which is more than
just being open source.
Thanks,
Tomeu
> I'll try adding these details as well.
>
> Thanks!> Regards,
> >
> > Tomeu
> >
> >>> +
> >>> +Internal Implementation
> >>> +=======================
> >>> +
> >>> +Memory Management
> >>> +-----------------
> >>> +The driver's memory manager creates virtual "IOMMU devices" that map to
> >>> +hardware context banks. This allows the driver to manage multiple isolated
> >>> +address spaces. The implementation uses a DMA-coherent backend to ensure data consistency
> >>> +between the CPU and DSP without manual cache maintenance in most cases.
> >>
> >> GEM usage?
> >>
> >>> +
> >>> +Debugging
> >>> +=========
> >>> +The driver includes extensive dynamic debug support. Enable it via the
> >>> +kernel's dynamic debug control:
> >>> +
> >>> +.. code-block:: bash
> >>> +
> >>> + echo "file drivers/accel/qda/* +p" > /sys/kernel/debug/dynamic_debug/control
> >>> +
> >>> +Testing
> >>> +=======
> >>> +The QDA driver can be exercised using the ``fastrpc_test`` utility from the
> >>> +FastRPC userspace library. Run the test application:
> >>
> >> pointer
> >>
> >>> +
> >>> +.. code-block:: bash
> >>> +
> >>> + fastrpc_test -d 3 -U 1 -t linux -a v68
> >>> +
> >>> +**Options**
> >>> +
> >>> +``-d domain``
> >>> + Select the DSP domain to run on:
> >>> +
> >>> + * ``0`` — ADSP
> >>> + * ``1`` — MDSP
> >>> + * ``2`` — SDSP
> >>> + * ``3`` — CDSP *(default on targets with CDSP)*
> >>> +
> >>> +``-U unsigned_PD``
> >>> + Select signed or unsigned protection domain:
> >>> +
> >>> + * ``0`` — signed PD
> >>> + * ``1`` — unsigned PD *(default)*
> >>> +
> >>> +``-t target``
> >>> + Target platform: ``android`` or ``linux`` *(default: linux)*
> >>> +
> >>> +``-a arch_version``
> >>> + DSP architecture version, e.g. ``v68``, ``v75`` *(default: v68)*
> >>>
> >>> --
> >>> 2.34.1
> >>>
> >>>
> >>
> >> --
> >> With best wishes
> >> Dmitry
>
^ permalink raw reply
* Re: [PATCH v7 07/42] KVM: guest_memfd: Only prepare folios for private pages
From: Suzuki K Poulose @ 2026-06-03 8:58 UTC (permalink / raw)
To: Ackerley Tng, aik, andrew.jones, binbin.wu, brauner, chao.p.peng,
david, ira.weiny, jmattson, jthoughton, michael.roth, oupton,
pankaj.gupta, qperret, rick.p.edgecombe, rientjes, shivankg,
steven.price, tabba, willy, wyihan, yan.y.zhao, forkloop,
pratyush, aneesh.kumar, liam, Paolo Bonzini, Sean Christopherson,
Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen, x86,
H. Peter Anvin, Steven Rostedt, Masami Hiramatsu,
Mathieu Desnoyers, Jonathan Corbet, Shuah Khan, Shuah Khan,
Vishal Annapurve, Andrew Morton, Chris Li, Kairui Song,
Kemeng Shi, Nhat Pham, Baoquan He, Barry Song, Axel Rasmussen,
Yuanchu Xie, Wei Xu, Youngjun Park, Qi Zheng, Shakeel Butt,
Kiryl Shutsemau, Jason Gunthorpe, Vlastimil Babka
Cc: kvm, linux-kernel, linux-trace-kernel, linux-doc, linux-kselftest,
linux-mm, linux-coco
In-Reply-To: <CAEvNRgE1dCVAxJWd_hyFa8N=m9JLfn97ip9tAmvHxspWJ50oGg@mail.gmail.com>
On 02/06/2026 23:41, Ackerley Tng wrote:
> Suzuki K Poulose <suzuki.poulose@arm.com> writes:
>
>>
>> [...snip...]
>>
>>>> @@ -914,7 +916,8 @@ int kvm_gmem_get_pfn(struct kvm *kvm, struct
>>>> kvm_memory_slot *slot,
>>>> folio_mark_uptodate(folio);
>>>> }
>>>> - r = kvm_gmem_prepare_folio(kvm, slot, gfn, folio);
>>>> + if (kvm_gmem_is_private_mem(inode, index))
>>>
>>> Don't we need to make sure the entire folio is private ? Not just the
>>> page at the index ?
>>> if (kvm_gmem_range_is_private(, index, folio_nr_pages(folio)) ?
>
> I was thinking to fix this when I do huge pages, for now guest_memfd is
> always just PAGE_SIZE, so just looking up index is fine.
>
> Is that okay?
Thats fine, but would be good to enforce that here, so that we don't
miss out when we add support for multi page folios.
>
>>
>> Or rather, we should go through the individual pages and apply the
>> prepare for ones that are private ?
>>
>> Suzuki
>>
>
> IIRC the plan was to make kvm_gmem_prepare_folio() idempotent, as in, if
> a page is already private, just skip. Currently sev_gmem_prepare() does
> a pr_debug(), which I guess is technically still idempotent.
>
> I'm thinking that the information tha needs tracking to make
> .gmem_prepare() idempotent should be tracked by arch code.
>
> Does this work for ARM CCA?
We don't hook into the prepare yet, but have plans to do that. We should
be able to handle the pages that are already private. (For CCA context,
RMI_GRANULE_DELEGATE_RANGE can skip over already REALM pages). So this
should be fine.
My point is, in a given folio, there may be pages that are shared.
Like you said, this could be dealt with when we support hugepages.
Suzuki
>
>>>
>>> [...snip...]
>>>
^ permalink raw reply
* [PATCH] Documentation: realtime.rst: adopt type aware kmalloc
From: Manuel Ebner @ 2026-06-03 9:07 UTC (permalink / raw)
To: Sebastian Andrzej Siewior, Clark Williams, Steven Rostedt,
Kees Cook, Jonathan Corbet, Shuah Khan,
open list:Real-time Linux (PREEMPT_RT), open list:DOCUMENTATION,
open list
Cc: Manuel Ebner
Update real-time/differences.rst to reflect new type-aware kmalloc-functions
as suggested in commit 2932ba8d9c99 ("slab: Introduce kmalloc_obj() and family")
Signed-off-by: Manuel Ebner <manuelebner@mailbox.org>
---
Documentation/core-api/real-time/differences.rst | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/Documentation/core-api/real-time/differences.rst b/Documentation/core-api/real-time/differences.rst
index 83ec9aa1c61a..6c2cc97b4938 100644
--- a/Documentation/core-api/real-time/differences.rst
+++ b/Documentation/core-api/real-time/differences.rst
@@ -128,7 +128,7 @@ PREEMPT_RT, the timer must be marked with the HRTIMER_MODE_HARD flag.
Memory allocation
-----------------
-The memory allocation APIs, such as kmalloc() and alloc_pages(), require a
+The memory allocation APIs, such as kmalloc_obj() and alloc_pages(), require a
gfp_t flag to indicate the allocation context. On non-PREEMPT_RT kernels, it is
necessary to use GFP_ATOMIC when allocating memory from interrupt context or
from sections where preemption is disabled. This is because the allocator must
--
2.54.0
^ permalink raw reply related
* Re: [PATCH v2 01/18] perf cs-etm: Queue context packets for frontend
From: Leo Yan @ 2026-06-03 9:08 UTC (permalink / raw)
To: James Clark
Cc: Suzuki K Poulose, Mike Leach, Arnaldo Carvalho de Melo,
Namhyung Kim, Jiri Olsa, Ian Rogers, Amir Ayupov, Jonathan Corbet,
Shuah Khan, Paschalis Mpeis, coresight, linux-perf-users,
linux-kernel, Arnaldo Carvalho de Melo, linux-doc
In-Reply-To: <20260602-james-cs-context-tracking-fix-v2-1-85b5ce6f55c6@linaro.org>
On Tue, Jun 02, 2026 at 03:26:43PM +0100, James Clark wrote:
[...]
> @@ -614,10 +621,12 @@ static int cs_etm__init_traceid_queue(struct cs_etm_queue *etmq,
>
> queue = &etmq->etm->queues.queue_array[etmq->queue_nr];
> tidq->trace_chan_id = trace_chan_id;
> - tidq->el = tidq->prev_packet_el = ocsd_EL_unknown;
> - tidq->thread = machine__findnew_thread(&etm->session->machines.host, -1,
> + tidq->decode_el = ocsd_EL_unknown;
> + tidq->frontend_thread = machine__findnew_thread(&etm->session->machines.host, -1,
> + queue->tid);
> + tidq->decode_thread = machine__findnew_thread(&etm->session->machines.host, -1,
> queue->tid);
> - tidq->prev_packet_thread = machine__idle_thread(&etm->session->machines.host);
> +
Redundant new line.
> tidq->packet = zalloc(sizeof(struct cs_etm_packet));
> if (!tidq->packet)
> @@ -751,20 +760,16 @@ static void cs_etm__packet_swap(struct cs_etm_auxtrace *etm,
> * Swap PACKET with PREV_PACKET: PACKET becomes PREV_PACKET for
> * the next incoming packet.
> *
> - * Threads and exception levels are also tracked for both the
> - * previous and current packets. This is because the previous
> - * packet is used for the 'from' IP for branch samples, so the
> - * thread at that time must also be assigned to that sample.
> - * Across discontinuity packets the thread can change, so by
> - * tracking the thread for the previous packet the branch sample
> - * will have the correct info.
> + * Track Exception levels for both the previous and current
> + * packets. This is because the previous packet's address is
> + * used for the 'from' IP for branch samples, so the previous EL
> + * must also be used so that sample shows it originates from the
> + * correct EL. Branches can't branch to a different thread, so
> + * no need to track the previous thread.
> */
> tmp = tidq->packet;
> tidq->packet = tidq->prev_packet;
> tidq->prev_packet = tmp;
> - tidq->prev_packet_el = tidq->el;
> - thread__put(tidq->prev_packet_thread);
> - tidq->prev_packet_thread = thread__get(tidq->thread);
As here no any code for EL swap, the comment above is a bit disconnected
with the code. Can we just remove the comment to avoid confusion?
Otherwise, looks good. Thanks for maturing the patch.
Leo
^ permalink raw reply
* Re: [PATCH v6 04/13] liveupdate: register luo_ser as KHO subtree
From: Mike Rapoport @ 2026-06-03 9:32 UTC (permalink / raw)
To: Pasha Tatashin
Cc: linux-kselftest, shuah, akpm, linux-mm, skhan, linux-doc,
linux-kernel, corbet, dmatlack, kexec, pratyush, skhawaja, graf
In-Reply-To: <178046942429.468621.9591914636403075487.b4-review@b4>
On Wed, Jun 03, 2026 at 09:50:24AM +0300, Mike Rapoport wrote:
> # Add your code comments below. There is no need to trim or delete
> # any existing content -- just insert your comments under the relevant
> # lines of code. Lines starting with "> " are quoted diff context and
> # lines starting with "| " are comments from other reviewers.
> # The final email will be reformatted automatically to include only
> # the sections that have your comments.
> #
looks like b4 review bug or misuse from my side :)
--
Sincerely yours,
Mike.
^ permalink raw reply
* [PATCH] Documentation: real-time/index: add entry
From: Manuel Ebner @ 2026-06-03 9:33 UTC (permalink / raw)
To: manuelebner
Cc: bigeasy, clrkwllms, corbet, linux-doc, linux-kernel,
linux-rt-devel, rostedt, skhan
In-Reply-To: <20260603080430.344391-2-manuelebner@mailbox.org>
I figured out the subject and changelog aren't good. It should be:
[PATCH] Documentation: real-time/index: add entry
Add reference to realtime/index.rst pointing to scheduler/sched-rt-group.rst
Signed-off-by: Manuel Ebner <manuelebner@mailbox.org>
---
I'm waiting for feedback before making [v2].
Thanks
Manuel
^ permalink raw reply
* Re: [PATCH mm-unstable v18 11/14] mm/khugepaged: Introduce mTHP collapse support
From: David Hildenbrand (Arm) @ 2026-06-03 9:55 UTC (permalink / raw)
To: Nico Pache
Cc: linux-doc, linux-kernel, linux-mm, linux-trace-kernel, aarcange,
akpm, anshuman.khandual, apopple, baohua, baolin.wang, byungchul,
catalin.marinas, cl, corbet, dave.hansen, dev.jain, gourry,
hannes, hughd, jack, jackmanb, jannh, jglisse, joshua.hahnjy, kas,
lance.yang, liam, ljs, mathieu.desnoyers, matthew.brost, mhiramat,
mhocko, peterx, pfalcato, rakie.kim, raquini, rdunlap,
richard.weiyang, rientjes, rostedt, rppt, ryan.roberts, shivankg,
sunnanyong, surenb, thomas.hellstrom, tiwai, vbabka, vishal.moola,
wangkefeng.wang, will, willy, yang, ying.huang, ziy, zokeefe,
Usama Arif, usamaarif642
In-Reply-To: <19639b08-5bf1-4974-9635-c458d512fa38@redhat.com>
On 6/2/26 19:23, Nico Pache wrote:
>
>
> On 6/1/26 7:15 AM, David Hildenbrand (Arm) wrote:
>>>
>>> So I looked into your items below. It seems logical, and I think it
>>> works the same way; however, your method seems slightly harder to
>>> understand due to all the edge cases and more error-prone to future
>>> changes (the stack holds implicit knowledge of the offset/order that
>>> must now be tracked in the edge cases).
>>>
>>> Given the stack is 24 bytes, I'm not sure if the extra complexity is
>>> worth saving that small amount of memory. Although we would also be
>>> getting rid of (3?) functions, so both approaches have pros and cons.
>>
>> I consider a simple forward loop over the offset ... less complexity compared to
>> a stack structure :)
>>
>>>
>>> I will implement a patch comparing your solution against mine and send
>>> it here, then we can decide which approach is better.
>>
>> Right, throw it over the fence and I'll see how to improve it further.
>
> Ok heres what the diff looks like on top of my V19.
>
> you can access the tree here https://gitlab.com/npache/linux/-/commits/mthp-v19?ref_type=heads for easier review.
>
> So far I have no problem with this approach it appeared cleaner than i thought. Did some light testing. Gonna throw it more through the ringer tomorrow.
It's very clean.
Almost too nice to be true ;)
[...]
> unsigned int nr_occupied_ptes, nr_ptes, max_ptes_none;
> enum scan_result last_result = SCAN_FAIL;
> - int collapsed = 0, stack_size = 0;
> + int collapsed = 0;
> bool alloc_failed = false;
> unsigned long collapse_address;
> - struct mthp_range range;
> - u16 offset;
> - u8 order;
> + unsigned int offset = 0;
> + unsigned int order = HPAGE_PMD_ORDER;
In include/linux/huge_mm.h we have
highest_order()
and
next_order()
They essentially allow you to get rid of the test_bit() and just jump to the
next enabled order right away.
I assume with only a handful of enabled_orders, that might be much more efficient.
I tried to optimize it and ended with the following, which is completely untested.
I think it might make sense to defer that and start with the simple approach you have.
I do wonder, though, about the last hunk below: should we bail out early if
enabled_orders is suddenly 0?
From 0d8ff955b3071f354b7fc9b627820fa374fa99dc Mon Sep 17 00:00:00 2001
From: "David Hildenbrand (Arm)" <david@kernel.org>
Date: Wed, 3 Jun 2026 11:52:44 +0200
Subject: [PATCH] tmp
Signed-off-by: David Hildenbrand (Arm) <david@kernel.org>
---
include/linux/huge_mm.h | 5 ++
mm/khugepaged.c | 132 ++++++++++++++++++++++------------------
2 files changed, 78 insertions(+), 59 deletions(-)
diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
index 48496f09909b..099318bc1181 100644
--- a/include/linux/huge_mm.h
+++ b/include/linux/huge_mm.h
@@ -205,6 +205,11 @@ static inline int highest_order(unsigned long orders)
return fls_long(orders) - 1;
}
+static inline int smallest_order(unsigned long orders)
+{
+ return __ffs(orders);
+}
+
static inline int next_order(unsigned long *orders, int prev)
{
*orders &= ~BIT(prev);
diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index 6de935e76ceb..49be9d1a88cb 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -99,8 +99,6 @@ static DEFINE_READ_MOSTLY_HASHTABLE(mm_slots_hash, MM_SLOTS_HASH_BITS);
static struct kmem_cache *mm_slot_cache __ro_after_init;
-#define KHUGEPAGED_MIN_MTHP_ORDER 2
-
struct collapse_control {
bool is_khugepaged;
@@ -1454,76 +1452,86 @@ static enum scan_result collapse_huge_page(struct mm_struct *mm, unsigned long s
*/
static enum scan_result mthp_collapse(struct mm_struct *mm,
unsigned long address, int referenced, int unmapped,
- struct collapse_control *cc, unsigned long enabled_orders)
+ struct collapse_control *cc, const unsigned long enabled_orders)
{
- unsigned int nr_occupied_ptes, nr_ptes, max_ptes_none;
enum scan_result last_result = SCAN_FAIL;
int collapsed = 0;
bool alloc_failed = false;
unsigned long collapse_address;
unsigned int offset = 0;
- unsigned int order = HPAGE_PMD_ORDER;
+ /* We cannot collapse anon folios to order-1 or order-0. */
+ VM_WARN_ON_ONCE(!enabled_order || (enabled_orders & 0x3));
while (offset < HPAGE_PMD_NR) {
- nr_ptes = 1UL << order;
-
- if (!test_bit(order, &enabled_orders))
- goto next_order;
-
- max_ptes_none = collapse_max_ptes_none(cc, NULL, order);
- nr_occupied_ptes = bitmap_weight_from(cc->mthp_present_ptes, offset,
- offset + nr_ptes);
-
- if (nr_occupied_ptes >= nr_ptes - max_ptes_none) {
- enum scan_result ret;
-
- collapse_address = address + offset * PAGE_SIZE;
- ret = collapse_huge_page(mm, collapse_address, referenced,
- unmapped, cc, order);
-
- switch (ret) {
- /* Cases where we continue to next collapse candidate */
- case SCAN_SUCCEED:
- collapsed += nr_ptes;
- fallthrough;
- case SCAN_PTE_MAPPED_HUGEPAGE:
- goto next_offset;
- /* Cases where lower orders might still succeed */
- case SCAN_ALLOC_HUGE_PAGE_FAIL:
- alloc_failed = true;
- fallthrough;
- case SCAN_LACK_REFERENCED_PAGE:
- case SCAN_EXCEED_NONE_PTE:
- case SCAN_EXCEED_SWAP_PTE:
- case SCAN_EXCEED_SHARED_PTE:
- case SCAN_PAGE_LOCK:
- case SCAN_PAGE_COUNT:
- case SCAN_PAGE_NULL:
- case SCAN_DEL_PAGE_LRU:
- case SCAN_PTE_NON_PRESENT:
- case SCAN_PTE_UFFD_WP:
- case SCAN_PAGE_LAZYFREE:
- last_result = ret;
- goto next_order;
- /* Cases where no further collapse is possible */
- case SCAN_PMD_MAPPED:
- fallthrough;
- default:
- last_result = ret;
- goto done;
+ /*
+ * We can only collapse to a maximum order for a given offset.
+ * So ignore all orders that do not apply to the current
+ * offset, then see if any order to collapse to remains.
+ */
+ unsigned long orders = enabled_orders & GENMASK(__ffs(offset), 0);
+ unsigned int order = highest_order(orders);
+
+ while (order) {
+ const unsigned int nr_ptes = 1UL << order;
+ unsigned int nr_occupied_ptes, max_ptes_none;
+
+ max_ptes_none = collapse_max_ptes_none(cc, NULL, order);
+ nr_occupied_ptes = bitmap_weight_from(cc->mthp_present_ptes, offset,
+ offset + nr_ptes);
+
+ if (nr_occupied_ptes >= nr_ptes - max_ptes_none) {
+ enum scan_result ret;
+
+ collapse_address = address + offset * PAGE_SIZE;
+ ret = collapse_huge_page(mm, collapse_address, referenced,
+ unmapped, cc, order);
+
+ switch (ret) {
+ /* Cases where we continue to next collapse candidate */
+ case SCAN_SUCCEED:
+ collapsed += nr_ptes;
+ fallthrough;
+ case SCAN_PTE_MAPPED_HUGEPAGE:
+ goto next_offset;
+ /* Cases where lower orders might still succeed */
+ case SCAN_ALLOC_HUGE_PAGE_FAIL:
+ alloc_failed = true;
+ fallthrough;
+ case SCAN_LACK_REFERENCED_PAGE:
+ case SCAN_EXCEED_NONE_PTE:
+ case SCAN_EXCEED_SWAP_PTE:
+ case SCAN_EXCEED_SHARED_PTE:
+ case SCAN_PAGE_LOCK:
+ case SCAN_PAGE_COUNT:
+ case SCAN_PAGE_NULL:
+ case SCAN_DEL_PAGE_LRU:
+ case SCAN_PTE_NON_PRESENT:
+ case SCAN_PTE_UFFD_WP:
+ case SCAN_PAGE_LAZYFREE:
+ last_result = ret;
+ break;
+ /* Cases where no further collapse is possible */
+ case SCAN_PMD_MAPPED:
+ fallthrough;
+ default:
+ last_result = ret;
+ goto done;
+ }
}
- }
-next_order:
- if (order > KHUGEPAGED_MIN_MTHP_ORDER &&
- (BIT(order) - 1) & enabled_orders) {
- order = order - 1;
- continue;
+ order = next_order(&orders, order);
}
+
next_offset:
- offset += nr_ptes;
- order = min_t(int, __ffs(offset), HPAGE_PMD_ORDER);
+ /*
+ * Continue with the next collapse candidate. If we do not
+ * have an order, skip to nest smallest mTHP we can collapse to.
+ */
+ if (order)
+ offset += 1UL << order;
+ else
+ offset = ALIGN(offset + 1, smallest_order(enabled_orders));
}
done:
if (collapsed)
@@ -1567,6 +1575,12 @@ static enum scan_result collapse_scan_pmd(struct mm_struct *mm,
enabled_orders = collapse_allowable_orders(vma, vma->vm_flags, tva_flags);
+ if (unlikely(!enabled_orders)) {
+ cc->progress++;
+ result = SCAN_SUCCEED;
+ goto out;
+ }
+
/*
* If PMD is the only enabled order, enforce max_ptes_none, otherwise
* scan all pages to populate the bitmap for mTHP collapse.
--
2.43.0
--
Cheers,
David
^ permalink raw reply related
* [PATCH v2 4/4] RISC-V: KVM: Add the eager_page_split module parameter
From: wang.yechao255 @ 2026-06-03 10:00 UTC (permalink / raw)
To: anup, atish.patra, pjw, palmer, aou, alex, linux-doc
Cc: kvm, kvm-riscv, linux-riscv, linux-kernel, wang.yechao255
In-Reply-To: <20260603175256408L0jnqGs1cJGc0ijCdujci@zte.com.cn>
From: Wang Yechao <wang.yechao255@zte.com.cn>
Add an eager_page_split module parameter for RISC-V KVM, following
the same approach as on x86. This parameter controls whether eager
page splitting is enabled. The default value is on.
When eager page splitting is enabled, KVM proactively splits large
pages (huge pages) into smaller pages when needed for dirty logging
or other operations. Disabling it can be beneficial for VM workloads
that rarely perform writes, or that only write to a small region of
memory, as it allows huge pages to remain intact for read accesses.
Signed-off-by: Wang Yechao <wang.yechao255@zte.com.cn>
---
Documentation/admin-guide/kernel-parameters.txt | 7 +++++--
arch/riscv/kvm/mmu.c | 13 ++++++++++---
2 files changed, 15 insertions(+), 5 deletions(-)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 4d0f545fb3ec..d443b5313b79 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -3059,7 +3059,7 @@ Kernel parameters
Default is 0 (don't ignore, but inject #GP)
kvm.eager_page_split=
- [KVM,X86] Controls whether or not KVM will try to
+ [KVM,X86,RISCV] Controls whether or not KVM will try to
proactively split all huge pages during dirty logging.
Eager page splitting reduces interruptions to vCPU
execution by eliminating the write-protection faults
@@ -3079,7 +3079,10 @@ Kernel parameters
the KVM_CLEAR_DIRTY ioctl, and only for the pages being
cleared.
- Eager page splitting is only supported when kvm.tdp_mmu=Y.
+ On x86, eager page splitting is only supported when
+ kvm.tdp_mmu=Y.
+
+ On RISCV, eager page splitting is supported by default.
Default is Y (on).
diff --git a/arch/riscv/kvm/mmu.c b/arch/riscv/kvm/mmu.c
index d04680687f4a..7a910c5a61fe 100644
--- a/arch/riscv/kvm/mmu.c
+++ b/arch/riscv/kvm/mmu.c
@@ -16,6 +16,9 @@
#include <asm/kvm_mmu.h>
#include <asm/kvm_nacl.h>
+bool __read_mostly eager_page_split = true;
+module_param(eager_page_split, bool, 0644);
+
static void mmu_wp_memory_region(struct kvm *kvm, int slot)
{
struct kvm_memslots *slots = kvm_memslots(kvm);
@@ -150,8 +153,10 @@ void kvm_arch_mmu_enable_log_dirty_pt_masked(struct kvm *kvm,
kvm_riscv_gstage_wp_range(&gstage, start, end);
- if (kvm_dirty_log_manual_protect_and_init_set(kvm))
- mmu_split_huge_pages(&gstage, start, end, true);
+ if (kvm_dirty_log_manual_protect_and_init_set(kvm)) {
+ if (READ_ONCE(eager_page_split))
+ mmu_split_huge_pages(&gstage, start, end, true);
+ }
}
void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
@@ -216,7 +221,9 @@ void kvm_arch_commit_memory_region(struct kvm *kvm,
if (kvm_dirty_log_manual_protect_and_init_set(kvm))
return;
mmu_wp_memory_region(kvm, new->id);
- mmu_split_memory_region(kvm, new->id);
+
+ if (READ_ONCE(eager_page_split))
+ mmu_split_memory_region(kvm, new->id);
}
}
--
2.43.5
^ permalink raw reply related
* Re: [PATCH mm-unstable v18 11/14] mm/khugepaged: Introduce mTHP collapse support
From: David Hildenbrand (Arm) @ 2026-06-03 10:00 UTC (permalink / raw)
To: Nico Pache
Cc: linux-doc, linux-kernel, linux-mm, linux-trace-kernel, aarcange,
akpm, anshuman.khandual, apopple, baohua, baolin.wang, byungchul,
catalin.marinas, cl, corbet, dave.hansen, dev.jain, gourry,
hannes, hughd, jack, jackmanb, jannh, jglisse, joshua.hahnjy, kas,
lance.yang, liam, ljs, mathieu.desnoyers, matthew.brost, mhiramat,
mhocko, peterx, pfalcato, rakie.kim, raquini, rdunlap,
richard.weiyang, rientjes, rostedt, rppt, ryan.roberts, shivankg,
sunnanyong, surenb, thomas.hellstrom, tiwai, vbabka, vishal.moola,
wangkefeng.wang, will, willy, yang, ying.huang, ziy, zokeefe,
Usama Arif, usamaarif642
In-Reply-To: <19639b08-5bf1-4974-9635-c458d512fa38@redhat.com>
> next_order:
> - if ((BIT(order) - 1) & enabled_orders) {
> - const u8 next_order = order - 1;
> - const u16 mid_offset = offset + (nr_ptes / 2);
> -
> - collapse_mthp_stack_push(cc, &stack_size, mid_offset,
> - next_order);
> - collapse_mthp_stack_push(cc, &stack_size, offset,
> - next_order);
> + if (order > KHUGEPAGED_MIN_MTHP_ORDER &&
> + (BIT(order) - 1) & enabled_orders) {
Why not a test_bit() ?
But, wouldn't you want to skip orders that are not enabled and try with the next
smaller one in any case before you advance the offset?
--
Cheers,
David
^ permalink raw reply
* Re: [PATCH v4 1/5] selftests/mm: make file helpers return errors
From: Mike Rapoport @ 2026-06-03 10:01 UTC (permalink / raw)
To: Sarthak Sharma
Cc: Andrew Morton, David Hildenbrand, Lorenzo Stoakes,
Liam R . Howlett, Vlastimil Babka, Mike Rapoport,
Suren Baghdasaryan, Michal Hocko, Shuah Khan, Zi Yan, Baolin Wang,
Nico Pache, Ryan Roberts, Dev Jain, Barry Song, Lance Yang,
Jason Gunthorpe, John Hubbard, Peter Xu, Leon Romanovsky,
Jonathan Corbet, Shuah Khan, Mark Brown, linux-mm,
linux-kselftest, linux-doc, linux-kernel
In-Reply-To: <20260527142432.230127-2-sarthak.sharma@arm.com>
On Wed, 27 May 2026 19:54:28 +0530, Sarthak Sharma <sarthak.sharma@arm.com> wrote:
Hi Sarthak,
>
> diff --git a/tools/testing/selftests/mm/hugepage_settings.c b/tools/testing/selftests/mm/hugepage_settings.c
> index 2eab2110ac6a..c2f97fe97e58 100644
> --- a/tools/testing/selftests/mm/hugepage_settings.c
> +++ b/tools/testing/selftests/mm/hugepage_settings.c
> @@ -61,7 +62,9 @@ int thp_read_string(const char *name, const char * const strings[])
> exit(EXIT_FAILURE);
> }
>
> - if (!read_file(path, buf, sizeof(buf))) {
> + ret = read_file(path, buf, sizeof(buf));
> + if (ret < 0) {
> + errno = -ret;
> perror(path);
Hmm, looks like those slipped ksft conversion :/
For kselftest compatibility this should be
printf("# %s: %s (%d)\n", path, strerror(errno), errno);
> @@ -103,12 +106,18 @@ void thp_write_string(const char *name, const char *val)
> printf("%s: Pathname is too long\n", __func__);
> exit(EXIT_FAILURE);
> }
> - write_file(path, val, strlen(val) + 1);
> + ret = write_file(path, val, strlen(val) + 1);
> + if (ret < 0) {
> + errno = -ret;
> + perror(path);
> + exit(EXIT_FAILURE);
These seem to repeat themself, how about we move prints to read/write
helpers?
Then it wouldn't matter for the callers what the exact error was, and no
need for errno games.
>
> diff --git a/tools/testing/selftests/mm/vm_util.c b/tools/testing/selftests/mm/vm_util.c
> index 311fc5b4513e..290e5c29123e 100644
> --- a/tools/testing/selftests/mm/vm_util.c
> +++ b/tools/testing/selftests/mm/vm_util.c
> @@ -703,62 +703,72 @@ int read_file(const char *path, char *buf, size_t buflen)
> int fd;
> ssize_t numread;
>
> + if (buflen < 2)
> + return -EINVAL;
heh, this feels overly protective :)
--
Sincerely yours,
Mike.
^ permalink raw reply
* Re: [PATCH v4 3/5] tools/lib/mm: move hugepage_settings out of selftests
From: Mike Rapoport @ 2026-06-03 10:01 UTC (permalink / raw)
To: Sarthak Sharma
Cc: Andrew Morton, David Hildenbrand, Lorenzo Stoakes,
Liam R . Howlett, Vlastimil Babka, Mike Rapoport,
Suren Baghdasaryan, Michal Hocko, Shuah Khan, Zi Yan, Baolin Wang,
Nico Pache, Ryan Roberts, Dev Jain, Barry Song, Lance Yang,
Jason Gunthorpe, John Hubbard, Peter Xu, Leon Romanovsky,
Jonathan Corbet, Shuah Khan, Mark Brown, linux-mm,
linux-kselftest, linux-doc, linux-kernel
In-Reply-To: <20260527142432.230127-4-sarthak.sharma@arm.com>
On Wed, 27 May 2026 19:54:30 +0530, Sarthak Sharma <sarthak.sharma@arm.com> wrote:
Hi Sarthak,
>
> diff --git a/tools/testing/selftests/mm/hugepage_settings.c b/tools/lib/mm/hugepage_settings.c
> similarity index 97%
> rename from tools/testing/selftests/mm/hugepage_settings.c
> rename to tools/lib/mm/hugepage_settings.c
> index c2f97fe97e58..c75b9c8f4a74 100644
> --- a/tools/testing/selftests/mm/hugepage_settings.c
> +++ b/tools/lib/mm/hugepage_settings.c
> @@ -419,8 +424,8 @@ int detect_hugetlb_page_sizes(unsigned long sizes[], int max)
> if (sscanf(entry->d_name, "hugepages-%zukB", &kb) != 1)
> continue;
> sizes[count++] = kb * 1024;
> - ksft_print_msg("[INFO] detected hugetlb page size: %zu KiB\n",
> - kb);
> + fprintf(stderr, "# [INFO] detected hugetlb page size: %zu KiB\n",
> + kb);
ksft_print_msg() prints to stdout, let's keep it for now.
--
Sincerely yours,
Mike.
^ permalink raw reply
* [PATCH v3 00/19] perf cs-etm: Queue context packets for frontend
From: James Clark @ 2026-06-03 10:17 UTC (permalink / raw)
To: Suzuki K Poulose, Mike Leach, Leo Yan, Arnaldo Carvalho de Melo,
Namhyung Kim, Jiri Olsa, Ian Rogers, Amir Ayupov, Jonathan Corbet,
Shuah Khan, Paschalis Mpeis
Cc: coresight, linux-perf-users, linux-kernel,
Arnaldo Carvalho de Melo, linux-doc, James Clark
Fix thread tracking when decoding Coresight trace and add a new test for
it.
The new test is added as a Perf test workload instead of a custom binary
with its own build system, but this requires a new feature in Perf test
to pass in control pipes which can enable and disable events. This
scopes the recording to just the workload and helps to reduce the amount
of data recorded in tracing tests.
With this new feature we can re-write all of the Coresight tests to make
use of it and remove the remaining binaries which fixes the following
issues:
* They didn't work in out of source builds
* A lot of the tests unnecessarily required root and didn't skip
without it
* They were mainly qualitative tests which didn't look for specific
behavior
Most importantly, the long build and runtime has been reduced. On a
Radxa Orion O6, unroll_loop_thread.c took 37s to compile which is longer
than the entire Perf build. Now the build time is negligible and the
before and after test runtimes for all the Coresight tests are:
| N1SDP | Orion O6
-----------------------------------
Before | 4m 0s | 14m 49s
After | 26s | 56s
-----------------------------------
Signed-off-by: James Clark <james.clark@linaro.org>
---
Changes in v3:
- Minor sashiko comments
- Close some more pipes
- Fix warning messages
- Error handling improvements
- Pass packet into cs_etm__synth_instruction_sample()
- Fixup stale comment (Leo)
- Link to v2: https://lore.kernel.org/r/20260602-james-cs-context-tracking-fix-v2-0-85b5ce6f55c6@linaro.org
Changes in v2:
- Add --workload-ctl option to Perf test
- Re-write all the Coresight tests and speed them up
- Pass packet to memory access function so frontend can use either the
previous or current packet's EL
- Link to v1: https://lore.kernel.org/r/20260526-james-cs-context-tracking-fix-v1-0-ebd602e18287@linaro.org
---
James Clark (19):
perf cs-etm: Queue context packets for frontend
perf test: Add workload-ctl option
perf test: Add a workload that forces context switches
perf test cs-etm: Test process attribution
perf test: Add deterministic workload
perf test cs-etm: Replace unroll loop thread with deterministic decode test
perf test cs-etm: Remove asm_pure_loop test
perf test cs-etm: Replace memcpy test with raw dump stress test
perf test: Add named_threads workload
perf test cs-etm: Test decoding for concurrent threads test
perf test cs-etm: Remove duplicate branch tests
perf test cs-etm: Skip if not root
perf test cs-etm: Reduce snapshot size
perf test cs-etm: Speed up basic test
perf test cs-etm: Remove unused Coresight workloads
perf test cs-etm: Make disassembly test use kcore
perf test cs-etm: Add all branch instructions to test
perf test cs-etm: Speed up disassembly test
perf test cs-etm: Move existing tests to coresight folder
Documentation/trace/coresight/coresight-perf.rst | 78 +------
MAINTAINERS | 2 -
tools/perf/Documentation/perf-test.txt | 18 +-
tools/perf/Makefile.perf | 14 +-
tools/perf/scripts/python/arm-cs-trace-disasm.py | 20 +-
tools/perf/tests/builtin-test.c | 187 +++++++++++++++-
tools/perf/tests/shell/coresight/Makefile | 29 ---
.../perf/tests/shell/coresight/Makefile.miniconfig | 14 --
tools/perf/tests/shell/coresight/asm_pure_loop.sh | 22 --
.../tests/shell/coresight/asm_pure_loop/.gitignore | 1 -
.../tests/shell/coresight/asm_pure_loop/Makefile | 34 ---
.../shell/coresight/asm_pure_loop/asm_pure_loop.S | 30 ---
.../tests/shell/coresight/concurrent_threads.sh | 45 ++++
.../tests/shell/coresight/context_switch_thread.sh | 69 ++++++
tools/perf/tests/shell/coresight/deterministic.sh | 71 +++++++
.../tests/shell/coresight/memcpy_thread/.gitignore | 1 -
.../tests/shell/coresight/memcpy_thread/Makefile | 33 ---
.../shell/coresight/memcpy_thread/memcpy_thread.c | 80 -------
.../tests/shell/coresight/memcpy_thread_16k_10.sh | 22 --
.../perf/tests/shell/coresight/raw_dump_stress.sh | 48 +++++
.../shell/{ => coresight}/test_arm_coresight.sh | 43 ++--
.../{ => coresight}/test_arm_coresight_disasm.sh | 17 +-
.../tests/shell/coresight/thread_loop/.gitignore | 1 -
.../tests/shell/coresight/thread_loop/Makefile | 33 ---
.../shell/coresight/thread_loop/thread_loop.c | 85 --------
.../shell/coresight/thread_loop_check_tid_10.sh | 23 --
.../shell/coresight/thread_loop_check_tid_2.sh | 23 --
.../shell/coresight/unroll_loop_thread/.gitignore | 1 -
.../shell/coresight/unroll_loop_thread/Makefile | 33 ---
.../unroll_loop_thread/unroll_loop_thread.c | 75 -------
.../tests/shell/coresight/unroll_loop_thread_10.sh | 22 --
tools/perf/tests/shell/lib/coresight.sh | 134 ------------
tools/perf/tests/tests.h | 3 +
tools/perf/tests/workloads/Build | 4 +
tools/perf/tests/workloads/context_switch_loop.c | 101 +++++++++
tools/perf/tests/workloads/deterministic.c | 39 ++++
tools/perf/tests/workloads/named_threads.c | 109 ++++++++++
tools/perf/util/cs-etm-decoder/cs-etm-decoder.c | 21 +-
tools/perf/util/cs-etm.c | 234 ++++++++++++---------
tools/perf/util/cs-etm.h | 8 +-
40 files changed, 889 insertions(+), 938 deletions(-)
---
base-commit: 5f0ca6b80b12bab1ce06839cdffb6148bb650ff4
change-id: 20260515-james-cs-context-tracking-fix-754998bae7ed
Best regards,
--
James Clark <james.clark@linaro.org>
^ permalink raw reply
* [PATCH v3 01/19] perf cs-etm: Queue context packets for frontend
From: James Clark @ 2026-06-03 10:17 UTC (permalink / raw)
To: Suzuki K Poulose, Mike Leach, Leo Yan, Arnaldo Carvalho de Melo,
Namhyung Kim, Jiri Olsa, Ian Rogers, Amir Ayupov, Jonathan Corbet,
Shuah Khan, Paschalis Mpeis
Cc: coresight, linux-perf-users, linux-kernel,
Arnaldo Carvalho de Melo, linux-doc, James Clark
In-Reply-To: <20260603-james-cs-context-tracking-fix-v3-0-c392945d9ed5@linaro.org>
PE_CONTEXT elements update the context ID and exception level, but the
decoder may still have prior packets cached for frontend processing.
Updating the context immediately in the decoder backend can make those
cached packets get consumed with the wrong thread or EL state.
Add a CS_ETM_CONTEXT packet carrying the TID and EL to the frontend,
this keeps context changes ordered with the rest of the packet stream
and avoids mismatches when synthesizing samples from cached packets.
Separate the memory access function into one for the frontend and one
for decoding. The frontend also needs memory access to attach the
instruction to samples. Because the frontend does memory access for
both previous and current packets, change all the frontend memory access
function signatures to take both a tidq and packet. But backend always
uses the current backend EL and thread from the tidq.
Treat context packets as a boundary for branch sample generation and
remove tidq->prev_packet_thread because it's not possible to branch to a
different thread, so only tracking the current thread is required for
sample generation.
Fixes: e573e978fb12 ("perf cs-etm: Inject capabilitity for CoreSight traces")
Reported-by: Amir Ayupov <aaupov@meta.com>
Closes: https://lore.kernel.org/linux-perf-users/20260515021135.1729028-1-aaupov@meta.com/
Co-authored-by: James Clark <james.clark@linaro.org>
Signed-off-by: Leo Yan <leo.yan@arm.com>
Signed-off-by: James Clark <james.clark@linaro.org>
---
tools/perf/util/cs-etm-decoder/cs-etm-decoder.c | 21 ++-
tools/perf/util/cs-etm.c | 234 ++++++++++++++----------
tools/perf/util/cs-etm.h | 8 +-
3 files changed, 162 insertions(+), 101 deletions(-)
diff --git a/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
index dee3020ceaa9..26940f1f1b0b 100644
--- a/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
+++ b/tools/perf/util/cs-etm-decoder/cs-etm-decoder.c
@@ -402,6 +402,8 @@ cs_etm_decoder__buffer_packet(struct cs_etm_queue *etmq,
packet_queue->packet_buffer[et].flags = 0;
packet_queue->packet_buffer[et].exception_number = UINT32_MAX;
packet_queue->packet_buffer[et].trace_chan_id = trace_chan_id;
+ packet_queue->packet_buffer[et].el = ocsd_EL_unknown;
+ packet_queue->packet_buffer[et].tid = -1;
if (packet_queue->packet_count == CS_ETM_PACKET_MAX_BUFFER - 1)
return OCSD_RESP_WAIT;
@@ -449,6 +451,7 @@ cs_etm_decoder__buffer_range(struct cs_etm_queue *etmq,
packet->last_instr_type = elem->last_i_type;
packet->last_instr_subtype = elem->last_i_subtype;
packet->last_instr_cond = elem->last_instr_cond;
+ packet->el = elem->context.exception_level;
if (elem->last_i_type == OCSD_INSTR_BR || elem->last_i_type == OCSD_INSTR_BR_INDIRECT)
packet->last_instr_taken_branch = elem->last_instr_exec;
@@ -525,7 +528,9 @@ cs_etm_decoder__set_tid(struct cs_etm_queue *etmq,
const ocsd_generic_trace_elem *elem,
const uint8_t trace_chan_id)
{
+ struct cs_etm_packet *packet;
pid_t tid = -1;
+ int ret;
/*
* Process the PE_CONTEXT packets if we have a valid contextID or VMID.
@@ -546,12 +551,18 @@ cs_etm_decoder__set_tid(struct cs_etm_queue *etmq,
break;
}
- if (cs_etm__etmq_set_tid_el(etmq, tid, trace_chan_id,
- elem->context.exception_level))
+ if (cs_etm__etmq_update_decode_context(etmq, trace_chan_id,
+ elem->context.exception_level, tid))
return OCSD_RESP_FATAL_SYS_ERR;
- if (tid == -1)
- return OCSD_RESP_CONT;
+ ret = cs_etm_decoder__buffer_packet(etmq, packet_queue, trace_chan_id,
+ CS_ETM_CONTEXT);
+ if (ret != OCSD_RESP_CONT && ret != OCSD_RESP_WAIT)
+ return ret;
+
+ packet = &packet_queue->packet_buffer[packet_queue->tail];
+ packet->tid = tid;
+ packet->el = elem->context.exception_level;
/*
* A timestamp is generated after a PE_CONTEXT element so make sure
@@ -559,7 +570,7 @@ cs_etm_decoder__set_tid(struct cs_etm_queue *etmq,
*/
cs_etm_decoder__reset_timestamp(packet_queue);
- return OCSD_RESP_CONT;
+ return ret;
}
static ocsd_datapath_resp_t cs_etm_decoder__gen_trace_elem_printer(
diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
index 40c6ddfa8c8d..ce570913669c 100644
--- a/tools/perf/util/cs-etm.c
+++ b/tools/perf/util/cs-etm.c
@@ -85,15 +85,22 @@ struct cs_etm_traceid_queue {
u64 period_instructions;
size_t last_branch_pos;
union perf_event *event_buf;
- struct thread *thread;
- struct thread *prev_packet_thread;
- ocsd_ex_level prev_packet_el;
- ocsd_ex_level el;
struct branch_stack *last_branch;
struct branch_stack *last_branch_rb;
struct cs_etm_packet *prev_packet;
struct cs_etm_packet *packet;
struct cs_etm_packet_queue packet_queue;
+
+ struct thread *decode_thread;
+ ocsd_ex_level decode_el;
+
+ /*
+ * The frontend accesses the EL from '[prev_]packet' because it needs
+ * previous EL for branch and current EL for instruction samples. It's
+ * not possible to change thread in a single branch sample so no need to
+ * store or access the thread through the packet.
+ */
+ struct thread *frontend_thread;
};
enum cs_etm_format {
@@ -614,10 +621,11 @@ static int cs_etm__init_traceid_queue(struct cs_etm_queue *etmq,
queue = &etmq->etm->queues.queue_array[etmq->queue_nr];
tidq->trace_chan_id = trace_chan_id;
- tidq->el = tidq->prev_packet_el = ocsd_EL_unknown;
- tidq->thread = machine__findnew_thread(&etm->session->machines.host, -1,
+ tidq->decode_el = ocsd_EL_unknown;
+ tidq->frontend_thread = machine__findnew_thread(&etm->session->machines.host, -1,
+ queue->tid);
+ tidq->decode_thread = machine__findnew_thread(&etm->session->machines.host, -1,
queue->tid);
- tidq->prev_packet_thread = machine__idle_thread(&etm->session->machines.host);
tidq->packet = zalloc(sizeof(struct cs_etm_packet));
if (!tidq->packet)
@@ -750,21 +758,10 @@ static void cs_etm__packet_swap(struct cs_etm_auxtrace *etm,
/*
* Swap PACKET with PREV_PACKET: PACKET becomes PREV_PACKET for
* the next incoming packet.
- *
- * Threads and exception levels are also tracked for both the
- * previous and current packets. This is because the previous
- * packet is used for the 'from' IP for branch samples, so the
- * thread at that time must also be assigned to that sample.
- * Across discontinuity packets the thread can change, so by
- * tracking the thread for the previous packet the branch sample
- * will have the correct info.
*/
tmp = tidq->packet;
tidq->packet = tidq->prev_packet;
tidq->prev_packet = tmp;
- tidq->prev_packet_el = tidq->el;
- thread__put(tidq->prev_packet_thread);
- tidq->prev_packet_thread = thread__get(tidq->thread);
}
}
@@ -937,8 +934,8 @@ static void cs_etm__free_traceid_queues(struct cs_etm_queue *etmq)
/* Free this traceid_queue from the array */
tidq = etmq->traceid_queues[idx];
- thread__zput(tidq->thread);
- thread__zput(tidq->prev_packet_thread);
+ thread__zput(tidq->frontend_thread);
+ thread__zput(tidq->decode_thread);
zfree(&tidq->event_buf);
zfree(&tidq->last_branch);
zfree(&tidq->last_branch_rb);
@@ -1083,47 +1080,43 @@ static u8 cs_etm__cpu_mode(struct cs_etm_queue *etmq, u64 address,
}
}
-static u32 cs_etm__mem_access(struct cs_etm_queue *etmq, u8 trace_chan_id,
- u64 address, size_t size, u8 *buffer,
- const ocsd_mem_space_acc_t mem_space)
+static u32 __cs_etm__mem_access(struct cs_etm_queue *etmq,
+ u64 address, size_t size, u8 *buffer,
+ const ocsd_mem_space_acc_t mem_space,
+ ocsd_ex_level el, struct thread *thread)
{
u8 cpumode;
u64 offset;
int len;
struct addr_location al;
struct dso *dso;
- struct cs_etm_traceid_queue *tidq;
int ret = 0;
if (!etmq)
return 0;
addr_location__init(&al);
- tidq = cs_etm__etmq_get_traceid_queue(etmq, trace_chan_id);
- if (!tidq)
- goto out;
/*
- * We've already tracked EL along side the PID in cs_etm__set_thread()
- * so double check that it matches what OpenCSD thinks as well. It
- * doesn't distinguish between EL0 and EL1 for this mem access callback
- * so we had to do the extra tracking. Skip validation if it's any of
- * the 'any' values.
+ * We track EL for the frontend and the backend when receiving context
+ * and range packets. OpenCSD doesn't distinguish between EL0 and EL1
+ * for this mem access callback so we had to do the extra tracking. Skip
+ * validation if it's any of the 'any' values.
*/
if (!(mem_space == OCSD_MEM_SPACE_ANY ||
mem_space == OCSD_MEM_SPACE_N || mem_space == OCSD_MEM_SPACE_S)) {
if (mem_space & OCSD_MEM_SPACE_EL1N) {
/* Includes both non secure EL1 and EL0 */
- assert(tidq->el == ocsd_EL1 || tidq->el == ocsd_EL0);
+ assert(el == ocsd_EL1 || el == ocsd_EL0);
} else if (mem_space & OCSD_MEM_SPACE_EL2)
- assert(tidq->el == ocsd_EL2);
+ assert(el == ocsd_EL2);
else if (mem_space & OCSD_MEM_SPACE_EL3)
- assert(tidq->el == ocsd_EL3);
+ assert(el == ocsd_EL3);
}
- cpumode = cs_etm__cpu_mode(etmq, address, tidq->el);
+ cpumode = cs_etm__cpu_mode(etmq, address, el);
- if (!thread__find_map(tidq->thread, cpumode, address, &al))
+ if (!thread__find_map(thread, cpumode, address, &al))
goto out;
dso = map__dso(al.map);
@@ -1138,7 +1131,7 @@ static u32 cs_etm__mem_access(struct cs_etm_queue *etmq, u8 trace_chan_id,
map__load(al.map);
- len = dso__data_read_offset(dso, maps__machine(thread__maps(tidq->thread)),
+ len = dso__data_read_offset(dso, maps__machine(thread__maps(thread)),
offset, buffer, size);
if (len <= 0) {
@@ -1158,6 +1151,30 @@ static u32 cs_etm__mem_access(struct cs_etm_queue *etmq, u8 trace_chan_id,
return ret;
}
+static u32 cs_etm__frontend_mem_access(struct cs_etm_queue *etmq,
+ struct cs_etm_traceid_queue *tidq,
+ struct cs_etm_packet *packet,
+ u64 address, size_t size, u8 *buffer)
+{
+ return __cs_etm__mem_access(etmq, address, size, buffer, 0, packet->el,
+ tidq->frontend_thread);
+}
+
+static u32 cs_etm__decoder_mem_access(struct cs_etm_queue *etmq, u8 trace_chan_id,
+ u64 address, size_t size, u8 *buffer,
+ const ocsd_mem_space_acc_t mem_space)
+{
+ struct cs_etm_traceid_queue *tidq;
+
+ tidq = cs_etm__etmq_get_traceid_queue(etmq, trace_chan_id);
+ if (!tidq)
+ return 0;
+
+ return __cs_etm__mem_access(etmq, address, size, buffer,
+ mem_space, tidq->decode_el,
+ tidq->decode_thread);
+}
+
static struct cs_etm_queue *cs_etm__alloc_queue(void)
{
struct cs_etm_queue *etmq = zalloc(sizeof(*etmq));
@@ -1333,12 +1350,13 @@ void cs_etm__reset_last_branch_rb(struct cs_etm_traceid_queue *tidq)
}
static inline int cs_etm__t32_instr_size(struct cs_etm_queue *etmq,
- u8 trace_chan_id, u64 addr)
+ struct cs_etm_traceid_queue *tidq,
+ struct cs_etm_packet *packet, u64 addr)
{
u8 instrBytes[2];
- cs_etm__mem_access(etmq, trace_chan_id, addr, ARRAY_SIZE(instrBytes),
- instrBytes, 0);
+ cs_etm__frontend_mem_access(etmq, tidq, packet, addr,
+ ARRAY_SIZE(instrBytes), instrBytes);
/*
* T32 instruction size is indicated by bits[15:11] of the first
* 16-bit word of the instruction: 0b11101, 0b11110 and 0b11111
@@ -1371,16 +1389,16 @@ u64 cs_etm__last_executed_instr(const struct cs_etm_packet *packet)
}
static inline u64 cs_etm__instr_addr(struct cs_etm_queue *etmq,
- u64 trace_chan_id,
- const struct cs_etm_packet *packet,
+ struct cs_etm_traceid_queue *tidq,
+ struct cs_etm_packet *packet,
u64 offset)
{
if (packet->isa == CS_ETM_ISA_T32) {
u64 addr = packet->start_addr;
while (offset) {
- addr += cs_etm__t32_instr_size(etmq,
- trace_chan_id, addr);
+ addr += cs_etm__t32_instr_size(etmq, tidq, packet,
+ addr);
offset--;
}
return addr;
@@ -1490,34 +1508,51 @@ cs_etm__get_trace(struct cs_etm_queue *etmq)
return etmq->buf_len;
}
-static void cs_etm__set_thread(struct cs_etm_queue *etmq,
- struct cs_etm_traceid_queue *tidq, pid_t tid,
- ocsd_ex_level el)
+/*
+ * Convert a raw thread number to a thread struct and assign it to **thread.
+ */
+static int cs_etm__etmq_update_thread(struct cs_etm_queue *etmq,
+ ocsd_ex_level el, pid_t tid,
+ struct thread **thread)
{
struct machine *machine = cs_etm__get_machine(etmq, el);
+ if (!machine || !*thread)
+ return -EINVAL;
+
if (tid != -1) {
- thread__zput(tidq->thread);
- tidq->thread = machine__find_thread(machine, -1, tid);
+ thread__zput(*thread);
+ *thread = machine__find_thread(machine, -1, tid);
}
/* Couldn't find a known thread */
- if (!tidq->thread)
- tidq->thread = machine__idle_thread(machine);
+ if (!*thread)
+ *thread = machine__idle_thread(machine);
- tidq->el = el;
+ return 0;
}
-int cs_etm__etmq_set_tid_el(struct cs_etm_queue *etmq, pid_t tid,
- u8 trace_chan_id, ocsd_ex_level el)
+/*
+ * Set the thread and EL of the decode context which is ahead in time of the
+ * frontend context.
+ */
+int cs_etm__etmq_update_decode_context(struct cs_etm_queue *etmq,
+ u8 trace_chan_id,
+ ocsd_ex_level el, pid_t tid)
{
struct cs_etm_traceid_queue *tidq;
+ int ret;
tidq = cs_etm__etmq_get_traceid_queue(etmq, trace_chan_id);
if (!tidq)
return -EINVAL;
- cs_etm__set_thread(etmq, tidq, tid, el);
+ ret = cs_etm__etmq_update_thread(etmq, el, tid,
+ &tidq->decode_thread);
+ if (ret)
+ return ret;
+
+ tidq->decode_el = el;
return 0;
}
@@ -1527,8 +1562,8 @@ bool cs_etm__etmq_is_timeless(struct cs_etm_queue *etmq)
}
static void cs_etm__copy_insn(struct cs_etm_queue *etmq,
- u64 trace_chan_id,
- const struct cs_etm_packet *packet,
+ struct cs_etm_traceid_queue *tidq,
+ struct cs_etm_packet *packet,
struct perf_sample *sample)
{
/*
@@ -1545,14 +1580,14 @@ static void cs_etm__copy_insn(struct cs_etm_queue *etmq,
* cs_etm__t32_instr_size().
*/
if (packet->isa == CS_ETM_ISA_T32)
- sample->insn_len = cs_etm__t32_instr_size(etmq, trace_chan_id,
+ sample->insn_len = cs_etm__t32_instr_size(etmq, tidq, packet,
sample->ip);
/* Otherwise, A64 and A32 instruction size are always 32-bit. */
else
sample->insn_len = 4;
- cs_etm__mem_access(etmq, trace_chan_id, sample->ip, sample->insn_len,
- (void *)sample->insn, 0);
+ cs_etm__frontend_mem_access(etmq, tidq, packet, sample->ip,
+ sample->insn_len, (void *)sample->insn);
}
u64 cs_etm__convert_sample_time(struct cs_etm_queue *etmq, u64 cs_timestamp)
@@ -1579,6 +1614,7 @@ static inline u64 cs_etm__resolve_sample_time(struct cs_etm_queue *etmq,
static int cs_etm__synth_instruction_sample(struct cs_etm_queue *etmq,
struct cs_etm_traceid_queue *tidq,
+ struct cs_etm_packet *packet,
u64 addr, u64 period)
{
int ret = 0;
@@ -1588,15 +1624,15 @@ static int cs_etm__synth_instruction_sample(struct cs_etm_queue *etmq,
perf_sample__init(&sample, /*all=*/true);
event->sample.header.type = PERF_RECORD_SAMPLE;
- event->sample.header.misc = cs_etm__cpu_mode(etmq, addr, tidq->el);
+ event->sample.header.misc = cs_etm__cpu_mode(etmq, addr, packet->el);
event->sample.header.size = sizeof(struct perf_event_header);
/* Set time field based on etm auxtrace config. */
sample.time = cs_etm__resolve_sample_time(etmq, tidq);
sample.ip = addr;
- sample.pid = thread__pid(tidq->thread);
- sample.tid = thread__tid(tidq->thread);
+ sample.pid = thread__pid(tidq->frontend_thread);
+ sample.tid = thread__tid(tidq->frontend_thread);
sample.id = etmq->etm->instructions_id;
sample.stream_id = etmq->etm->instructions_id;
sample.period = period;
@@ -1604,7 +1640,7 @@ static int cs_etm__synth_instruction_sample(struct cs_etm_queue *etmq,
sample.flags = tidq->prev_packet->flags;
sample.cpumode = event->sample.header.misc;
- cs_etm__copy_insn(etmq, tidq->trace_chan_id, tidq->packet, &sample);
+ cs_etm__copy_insn(etmq, tidq, tidq->packet, &sample);
if (etm->synth_opts.last_branch)
sample.branch_stack = tidq->last_branch;
@@ -1649,15 +1685,15 @@ static int cs_etm__synth_branch_sample(struct cs_etm_queue *etmq,
event->sample.header.type = PERF_RECORD_SAMPLE;
event->sample.header.misc = cs_etm__cpu_mode(etmq, ip,
- tidq->prev_packet_el);
+ tidq->prev_packet->el);
event->sample.header.size = sizeof(struct perf_event_header);
/* Set time field based on etm auxtrace config. */
sample.time = cs_etm__resolve_sample_time(etmq, tidq);
sample.ip = ip;
- sample.pid = thread__pid(tidq->prev_packet_thread);
- sample.tid = thread__tid(tidq->prev_packet_thread);
+ sample.pid = thread__pid(tidq->frontend_thread);
+ sample.tid = thread__tid(tidq->frontend_thread);
sample.addr = cs_etm__first_executed_instr(tidq->packet);
sample.id = etmq->etm->branches_id;
sample.stream_id = etmq->etm->branches_id;
@@ -1666,8 +1702,7 @@ static int cs_etm__synth_branch_sample(struct cs_etm_queue *etmq,
sample.flags = tidq->prev_packet->flags;
sample.cpumode = event->sample.header.misc;
- cs_etm__copy_insn(etmq, tidq->trace_chan_id, tidq->prev_packet,
- &sample);
+ cs_etm__copy_insn(etmq, tidq, tidq->prev_packet, &sample);
/*
* perf report cannot handle events without a branch stack
@@ -1788,7 +1823,6 @@ static int cs_etm__sample(struct cs_etm_queue *etmq,
{
struct cs_etm_auxtrace *etm = etmq->etm;
int ret;
- u8 trace_chan_id = tidq->trace_chan_id;
u64 instrs_prev;
/* Get instructions remainder from previous packet */
@@ -1874,10 +1908,10 @@ static int cs_etm__sample(struct cs_etm_queue *etmq,
* been executed, but PC has not advanced to next
* instruction)
*/
- addr = cs_etm__instr_addr(etmq, trace_chan_id,
- tidq->packet, offset - 1);
+ addr = cs_etm__instr_addr(etmq, tidq, tidq->packet,
+ offset - 1);
ret = cs_etm__synth_instruction_sample(
- etmq, tidq, addr,
+ etmq, tidq, tidq->packet, addr,
etm->instructions_sample_period);
if (ret)
return ret;
@@ -1959,7 +1993,7 @@ static int cs_etm__flush(struct cs_etm_queue *etmq,
addr = cs_etm__last_executed_instr(tidq->prev_packet);
err = cs_etm__synth_instruction_sample(
- etmq, tidq, addr,
+ etmq, tidq, tidq->prev_packet, addr,
tidq->period_instructions);
if (err)
return err;
@@ -2014,7 +2048,7 @@ static int cs_etm__end_block(struct cs_etm_queue *etmq,
addr = cs_etm__last_executed_instr(tidq->prev_packet);
err = cs_etm__synth_instruction_sample(
- etmq, tidq, addr,
+ etmq, tidq, tidq->prev_packet, addr,
tidq->period_instructions);
if (err)
return err;
@@ -2051,9 +2085,9 @@ static int cs_etm__get_data_block(struct cs_etm_queue *etmq)
return etmq->buf_len;
}
-static bool cs_etm__is_svc_instr(struct cs_etm_queue *etmq, u8 trace_chan_id,
- struct cs_etm_packet *packet,
- u64 end_addr)
+static bool cs_etm__is_svc_instr(struct cs_etm_queue *etmq,
+ struct cs_etm_traceid_queue *tidq,
+ struct cs_etm_packet *packet, u64 end_addr)
{
/* Initialise to keep compiler happy */
u16 instr16 = 0;
@@ -2075,8 +2109,8 @@ static bool cs_etm__is_svc_instr(struct cs_etm_queue *etmq, u8 trace_chan_id,
* so below only read 2 bytes as instruction size for T32.
*/
addr = end_addr - 2;
- cs_etm__mem_access(etmq, trace_chan_id, addr, sizeof(instr16),
- (u8 *)&instr16, 0);
+ cs_etm__frontend_mem_access(etmq, tidq, packet, addr,
+ sizeof(instr16), (u8 *)&instr16);
if ((instr16 & 0xFF00) == 0xDF00)
return true;
@@ -2091,8 +2125,8 @@ static bool cs_etm__is_svc_instr(struct cs_etm_queue *etmq, u8 trace_chan_id,
* +---------+---------+-------------------------+
*/
addr = end_addr - 4;
- cs_etm__mem_access(etmq, trace_chan_id, addr, sizeof(instr32),
- (u8 *)&instr32, 0);
+ cs_etm__frontend_mem_access(etmq, tidq, packet, addr,
+ sizeof(instr32), (u8 *)&instr32);
if ((instr32 & 0x0F000000) == 0x0F000000 &&
(instr32 & 0xF0000000) != 0xF0000000)
return true;
@@ -2108,8 +2142,8 @@ static bool cs_etm__is_svc_instr(struct cs_etm_queue *etmq, u8 trace_chan_id,
* +-----------------------+---------+-----------+
*/
addr = end_addr - 4;
- cs_etm__mem_access(etmq, trace_chan_id, addr, sizeof(instr32),
- (u8 *)&instr32, 0);
+ cs_etm__frontend_mem_access(etmq, tidq, packet, addr,
+ sizeof(instr32), (u8 *)&instr32);
if ((instr32 & 0xFFE0001F) == 0xd4000001)
return true;
@@ -2125,7 +2159,6 @@ static bool cs_etm__is_svc_instr(struct cs_etm_queue *etmq, u8 trace_chan_id,
static bool cs_etm__is_syscall(struct cs_etm_queue *etmq,
struct cs_etm_traceid_queue *tidq, u64 magic)
{
- u8 trace_chan_id = tidq->trace_chan_id;
struct cs_etm_packet *packet = tidq->packet;
struct cs_etm_packet *prev_packet = tidq->prev_packet;
@@ -2140,7 +2173,7 @@ static bool cs_etm__is_syscall(struct cs_etm_queue *etmq,
*/
if (magic == __perf_cs_etmv4_magic) {
if (packet->exception_number == CS_ETMV4_EXC_CALL &&
- cs_etm__is_svc_instr(etmq, trace_chan_id, prev_packet,
+ cs_etm__is_svc_instr(etmq, tidq, prev_packet,
prev_packet->end_addr))
return true;
}
@@ -2178,7 +2211,6 @@ static bool cs_etm__is_sync_exception(struct cs_etm_queue *etmq,
struct cs_etm_traceid_queue *tidq,
u64 magic)
{
- u8 trace_chan_id = tidq->trace_chan_id;
struct cs_etm_packet *packet = tidq->packet;
struct cs_etm_packet *prev_packet = tidq->prev_packet;
@@ -2204,7 +2236,7 @@ static bool cs_etm__is_sync_exception(struct cs_etm_queue *etmq,
* (SMC, HVC) are taken as sync exceptions.
*/
if (packet->exception_number == CS_ETMV4_EXC_CALL &&
- !cs_etm__is_svc_instr(etmq, trace_chan_id, prev_packet,
+ !cs_etm__is_svc_instr(etmq, tidq, prev_packet,
prev_packet->end_addr))
return true;
@@ -2228,7 +2260,6 @@ static int cs_etm__set_sample_flags(struct cs_etm_queue *etmq,
{
struct cs_etm_packet *packet = tidq->packet;
struct cs_etm_packet *prev_packet = tidq->prev_packet;
- u8 trace_chan_id = tidq->trace_chan_id;
u64 magic;
int ret;
@@ -2309,11 +2340,11 @@ static int cs_etm__set_sample_flags(struct cs_etm_queue *etmq,
if (prev_packet->flags == (PERF_IP_FLAG_BRANCH |
PERF_IP_FLAG_RETURN |
PERF_IP_FLAG_INTERRUPT) &&
- cs_etm__is_svc_instr(etmq, trace_chan_id,
- packet, packet->start_addr))
+ cs_etm__is_svc_instr(etmq, tidq, packet, packet->start_addr)) {
prev_packet->flags = PERF_IP_FLAG_BRANCH |
PERF_IP_FLAG_RETURN |
PERF_IP_FLAG_SYSCALLRET;
+ }
break;
case CS_ETM_DISCONTINUITY:
/*
@@ -2394,6 +2425,7 @@ static int cs_etm__set_sample_flags(struct cs_etm_queue *etmq,
PERF_IP_FLAG_RETURN |
PERF_IP_FLAG_INTERRUPT;
break;
+ case CS_ETM_CONTEXT:
case CS_ETM_EMPTY:
default:
break;
@@ -2469,6 +2501,19 @@ static int cs_etm__process_traceid_queue(struct cs_etm_queue *etmq,
*/
cs_etm__sample(etmq, tidq);
break;
+ case CS_ETM_CONTEXT:
+ /*
+ * Update context but don't swap packet. Keep the
+ * previous one for branch source address info, if
+ * tracing the kernel the context packet will be emitted
+ * between two ranges.
+ */
+ ret = cs_etm__etmq_update_thread(etmq, tidq->packet->el,
+ tidq->packet->tid,
+ &tidq->frontend_thread);
+ if (ret)
+ goto out;
+ break;
case CS_ETM_EXCEPTION:
case CS_ETM_EXCEPTION_RET:
/*
@@ -2497,6 +2542,7 @@ static int cs_etm__process_traceid_queue(struct cs_etm_queue *etmq,
}
}
+out:
return ret;
}
@@ -2620,7 +2666,7 @@ static int cs_etm__process_timeless_queues(struct cs_etm_auxtrace *etm,
if (!tidq)
continue;
- if (tid == -1 || thread__tid(tidq->thread) == tid)
+ if (tid == -1 || thread__tid(tidq->frontend_thread) == tid)
cs_etm__run_per_thread_timeless_decoder(etmq);
} else
cs_etm__run_per_cpu_timeless_decoder(etmq);
@@ -3328,7 +3374,7 @@ static int cs_etm__create_queue_decoders(struct cs_etm_queue *etmq)
*/
if (cs_etm_decoder__add_mem_access_cb(etmq->decoder,
0x0L, ((u64) -1L),
- cs_etm__mem_access))
+ cs_etm__decoder_mem_access))
goto out_free_decoder;
zfree(&t_params);
diff --git a/tools/perf/util/cs-etm.h b/tools/perf/util/cs-etm.h
index aa9bb4a32eca..b81099c2b301 100644
--- a/tools/perf/util/cs-etm.h
+++ b/tools/perf/util/cs-etm.h
@@ -158,6 +158,7 @@ enum cs_etm_sample_type {
CS_ETM_DISCONTINUITY,
CS_ETM_EXCEPTION,
CS_ETM_EXCEPTION_RET,
+ CS_ETM_CONTEXT,
};
enum cs_etm_isa {
@@ -184,6 +185,8 @@ struct cs_etm_packet {
u8 last_instr_size;
u8 trace_chan_id;
int cpu;
+ int el;
+ pid_t tid;
};
#define CS_ETM_PACKET_MAX_BUFFER 1024
@@ -259,8 +262,9 @@ enum cs_etm_pid_fmt {
#include <opencsd/ocsd_if_types.h>
int cs_etm__get_cpu(struct cs_etm_queue *etmq, u8 trace_chan_id, int *cpu);
enum cs_etm_pid_fmt cs_etm__get_pid_fmt(struct cs_etm_queue *etmq);
-int cs_etm__etmq_set_tid_el(struct cs_etm_queue *etmq, pid_t tid,
- u8 trace_chan_id, ocsd_ex_level el);
+int cs_etm__etmq_update_decode_context(struct cs_etm_queue *etmq,
+ u8 trace_chan_id, ocsd_ex_level el,
+ pid_t tid);
bool cs_etm__etmq_is_timeless(struct cs_etm_queue *etmq);
void cs_etm__etmq_set_traceid_queue_timestamp(struct cs_etm_queue *etmq,
u8 trace_chan_id);
--
2.34.1
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