Extend the rseq ABI to expose a NUMA node ID and a vm_vcpu_id field.
The NUMA node ID field allows implementing a faster getcpu(2) in libc.
The virtual cpu id allows ideal scaling (down or up) of user-space
per-cpu data structures. The virtual cpu ids allocated within a memory
space are tracked by the scheduler, which takes into account the number
of concurrently running threads, thus implicitly considering the number
of threads, the cpu affinity, the cpusets applying to those threads, and
the number of logical cores on the system.
This series is based on the v5.19 tag.
Thanks,
Mathieu
Mathieu Desnoyers (25):
rseq: Introduce feature size and alignment ELF auxiliary vector
entries
rseq: Introduce extensible rseq ABI
rseq: Extend struct rseq with numa node id
selftests/rseq: Use ELF auxiliary vector for extensible rseq
selftests/rseq: Implement rseq numa node id field selftest
lib: Invert _find_next_bit source arguments
lib: Implement find_{first,next}_{zero,one}_and_zero_bit
cpumask: Implement cpumask_{first,next}_{zero,one}_and_zero
sched: Introduce per memory space current virtual cpu id
rseq: Extend struct rseq with per memory space vcpu id
selftests/rseq: Remove RSEQ_SKIP_FASTPATH code
selftests/rseq: Implement rseq vm_vcpu_id field support
selftests/rseq: x86: Template memory ordering and percpu access mode
selftests/rseq: arm: Template memory ordering and percpu access mode
selftests/rseq: arm64: Template memory ordering and percpu access mode
selftests/rseq: mips: Template memory ordering and percpu access mode
selftests/rseq: ppc: Template memory ordering and percpu access mode
selftests/rseq: s390: Template memory ordering and percpu access mode
selftests/rseq: riscv: Template memory ordering and percpu access mode
selftests/rseq: Implement basic percpu ops vm_vcpu_id test
selftests/rseq: Implement parametrized vm_vcpu_id test
selftests/rseq: x86: Implement rseq_load_u32_u32
selftests/rseq: Implement numa node id vs vm_vcpu_id invariant test
selftests/rseq: parametrized test: Report/abort on negative cpu id
tracing/rseq: Add mm_vcpu_id field to rseq_update
fs/binfmt_elf.c | 5 +
fs/exec.c | 6 +
include/linux/cpumask.h | 86 ++
include/linux/find.h | 123 +-
include/linux/mm.h | 25 +
include/linux/mm_types.h | 110 +-
include/linux/sched.h | 9 +
include/trace/events/rseq.h | 7 +-
include/uapi/linux/auxvec.h | 2 +
include/uapi/linux/rseq.h | 22 +
init/Kconfig | 4 +
kernel/fork.c | 11 +-
kernel/ptrace.c | 2 +-
kernel/rseq.c | 61 +-
kernel/sched/core.c | 49 +
kernel/sched/sched.h | 166 +++
kernel/signal.c | 2 +
lib/find_bit.c | 17 +-
tools/include/linux/find.h | 9 +-
tools/lib/find_bit.c | 17 +-
tools/testing/selftests/rseq/.gitignore | 5 +
tools/testing/selftests/rseq/Makefile | 20 +-
.../testing/selftests/rseq/basic_numa_test.c | 117 ++
.../selftests/rseq/basic_percpu_ops_test.c | 46 +-
tools/testing/selftests/rseq/basic_test.c | 4 +
tools/testing/selftests/rseq/compiler.h | 6 +
tools/testing/selftests/rseq/param_test.c | 157 ++-
tools/testing/selftests/rseq/rseq-abi.h | 22 +
tools/testing/selftests/rseq/rseq-arm-bits.h | 505 +++++++
tools/testing/selftests/rseq/rseq-arm.h | 701 +---------
.../testing/selftests/rseq/rseq-arm64-bits.h | 392 ++++++
tools/testing/selftests/rseq/rseq-arm64.h | 520 +------
.../testing/selftests/rseq/rseq-bits-reset.h | 10 +
.../selftests/rseq/rseq-bits-template.h | 39 +
tools/testing/selftests/rseq/rseq-mips-bits.h | 462 +++++++
tools/testing/selftests/rseq/rseq-mips.h | 646 +--------
tools/testing/selftests/rseq/rseq-ppc-bits.h | 454 +++++++
tools/testing/selftests/rseq/rseq-ppc.h | 617 +--------
.../testing/selftests/rseq/rseq-riscv-bits.h | 410 ++++++
tools/testing/selftests/rseq/rseq-riscv.h | 529 +-------
tools/testing/selftests/rseq/rseq-s390-bits.h | 474 +++++++
tools/testing/selftests/rseq/rseq-s390.h | 495 +------
tools/testing/selftests/rseq/rseq-skip.h | 65 -
tools/testing/selftests/rseq/rseq-x86-bits.h | 1036 ++++++++++++++
tools/testing/selftests/rseq/rseq-x86.h | 1193 +----------------
tools/testing/selftests/rseq/rseq.c | 86 +-
tools/testing/selftests/rseq/rseq.h | 229 +++-
.../testing/selftests/rseq/run_param_test.sh | 5 +
48 files changed, 5286 insertions(+), 4692 deletions(-)
create mode 100644 tools/testing/selftests/rseq/basic_numa_test.c
create mode 100644 tools/testing/selftests/rseq/rseq-arm-bits.h
create mode 100644 tools/testing/selftests/rseq/rseq-arm64-bits.h
create mode 100644 tools/testing/selftests/rseq/rseq-bits-reset.h
create mode 100644 tools/testing/selftests/rseq/rseq-bits-template.h
create mode 100644 tools/testing/selftests/rseq/rseq-mips-bits.h
create mode 100644 tools/testing/selftests/rseq/rseq-ppc-bits.h
create mode 100644 tools/testing/selftests/rseq/rseq-riscv-bits.h
create mode 100644 tools/testing/selftests/rseq/rseq-s390-bits.h
delete mode 100644 tools/testing/selftests/rseq/rseq-skip.h
create mode 100644 tools/testing/selftests/rseq/rseq-x86-bits.h
--
2.25.1
Test the NUMA node id extension rseq field. Compare it against the value
returned by the getcpu(2) system call while pinned on a specific core.
Signed-off-by: Mathieu Desnoyers <[email protected]>
---
tools/testing/selftests/rseq/basic_test.c | 4 ++++
tools/testing/selftests/rseq/rseq-abi.h | 8 +++++++
tools/testing/selftests/rseq/rseq.c | 18 +++++++++++++++
tools/testing/selftests/rseq/rseq.h | 28 +++++++++++++++++++++++
4 files changed, 58 insertions(+)
diff --git a/tools/testing/selftests/rseq/basic_test.c b/tools/testing/selftests/rseq/basic_test.c
index d8efbfb89193..295eea16466f 100644
--- a/tools/testing/selftests/rseq/basic_test.c
+++ b/tools/testing/selftests/rseq/basic_test.c
@@ -22,6 +22,8 @@ void test_cpu_pointer(void)
CPU_ZERO(&test_affinity);
for (i = 0; i < CPU_SETSIZE; i++) {
if (CPU_ISSET(i, &affinity)) {
+ int node;
+
CPU_SET(i, &test_affinity);
sched_setaffinity(0, sizeof(test_affinity),
&test_affinity);
@@ -29,6 +31,8 @@ void test_cpu_pointer(void)
assert(rseq_current_cpu() == i);
assert(rseq_current_cpu_raw() == i);
assert(rseq_cpu_start() == i);
+ node = rseq_fallback_current_node();
+ assert(rseq_current_node_id() == node);
CPU_CLR(i, &test_affinity);
}
}
diff --git a/tools/testing/selftests/rseq/rseq-abi.h b/tools/testing/selftests/rseq/rseq-abi.h
index 00ac846d85b0..a1faa9162d52 100644
--- a/tools/testing/selftests/rseq/rseq-abi.h
+++ b/tools/testing/selftests/rseq/rseq-abi.h
@@ -147,6 +147,14 @@ struct rseq_abi {
*/
__u32 flags;
+ /*
+ * Restartable sequences node_id field. Updated by the kernel. Read by
+ * user-space with single-copy atomicity semantics. This field should
+ * only be read by the thread which registered this data structure.
+ * Aligned on 32-bit. Contains the current NUMA node ID.
+ */
+ __u32 node_id;
+
/*
* Flexible array member at end of structure, after last feature field.
*/
diff --git a/tools/testing/selftests/rseq/rseq.c b/tools/testing/selftests/rseq/rseq.c
index 20ea536d1012..0a96c3c779cd 100644
--- a/tools/testing/selftests/rseq/rseq.c
+++ b/tools/testing/selftests/rseq/rseq.c
@@ -79,6 +79,11 @@ static int sys_rseq(struct rseq_abi *rseq_abi, uint32_t rseq_len,
return syscall(__NR_rseq, rseq_abi, rseq_len, flags, sig);
}
+static int sys_getcpu(unsigned *cpu, unsigned *node)
+{
+ return syscall(__NR_getcpu, cpu, node, NULL);
+}
+
int rseq_available(void)
{
int rc;
@@ -199,3 +204,16 @@ int32_t rseq_fallback_current_cpu(void)
}
return cpu;
}
+
+int32_t rseq_fallback_current_node(void)
+{
+ uint32_t cpu_id, node_id;
+ int ret;
+
+ ret = sys_getcpu(&cpu_id, &node_id);
+ if (ret) {
+ perror("sys_getcpu()");
+ return ret;
+ }
+ return (int32_t) node_id;
+}
diff --git a/tools/testing/selftests/rseq/rseq.h b/tools/testing/selftests/rseq/rseq.h
index 95adc1e1b0db..fd17d0e54a1b 100644
--- a/tools/testing/selftests/rseq/rseq.h
+++ b/tools/testing/selftests/rseq/rseq.h
@@ -20,6 +20,15 @@
#include "rseq-abi.h"
#include "compiler.h"
+#ifndef rseq_sizeof_field
+#define rseq_sizeof_field(TYPE, MEMBER) sizeof((((TYPE *)0)->MEMBER))
+#endif
+
+#ifndef rseq_offsetofend
+#define rseq_offsetofend(TYPE, MEMBER) \
+ (offsetof(TYPE, MEMBER) + rseq_sizeof_field(TYPE, MEMBER))
+#endif
+
/*
* Empty code injection macros, override when testing.
* It is important to consider that the ASM injection macros need to be
@@ -128,6 +137,11 @@ int rseq_unregister_current_thread(void);
*/
int32_t rseq_fallback_current_cpu(void);
+/*
+ * Restartable sequence fallback for reading the current node number.
+ */
+int32_t rseq_fallback_current_node(void);
+
/*
* Values returned can be either the current CPU number, -1 (rseq is
* uninitialized), or -2 (rseq initialization has failed).
@@ -163,6 +177,20 @@ static inline uint32_t rseq_current_cpu(void)
return cpu;
}
+static inline bool rseq_node_id_available(void)
+{
+ return (int) rseq_feature_size >= rseq_offsetofend(struct rseq_abi, node_id);
+}
+
+/*
+ * Current NUMA node number.
+ */
+static inline uint32_t rseq_current_node_id(void)
+{
+ assert(rseq_node_id_available());
+ return RSEQ_ACCESS_ONCE(rseq_get_abi()->node_id);
+}
+
static inline void rseq_clear_rseq_cs(void)
{
RSEQ_WRITE_ONCE(rseq_get_abi()->rseq_cs.arch.ptr, 0);
--
2.25.1
On 2022-09-21 15:24, Mathieu Desnoyers wrote:
> Extend the rseq ABI to expose a NUMA node ID and a vm_vcpu_id field.
>
> The NUMA node ID field allows implementing a faster getcpu(2) in libc.
>
> The virtual cpu id allows ideal scaling (down or up) of user-space
> per-cpu data structures. The virtual cpu ids allocated within a memory
> space are tracked by the scheduler, which takes into account the number
> of concurrently running threads, thus implicitly considering the number
> of threads, the cpu affinity, the cpusets applying to those threads, and
> the number of logical cores on the system.
>
> This series is based on the v5.19 tag.
Hi Peter,
I'm having MTA issues at the moment. I will resend the series as soon as
I can get hold of my sysadmin.
Sorry about that.
Thanks,
Mathieu
>
> Thanks,
>
> Mathieu
>
> Mathieu Desnoyers (25):
> rseq: Introduce feature size and alignment ELF auxiliary vector
> entries
> rseq: Introduce extensible rseq ABI
> rseq: Extend struct rseq with numa node id
> selftests/rseq: Use ELF auxiliary vector for extensible rseq
> selftests/rseq: Implement rseq numa node id field selftest
> lib: Invert _find_next_bit source arguments
> lib: Implement find_{first,next}_{zero,one}_and_zero_bit
> cpumask: Implement cpumask_{first,next}_{zero,one}_and_zero
> sched: Introduce per memory space current virtual cpu id
> rseq: Extend struct rseq with per memory space vcpu id
> selftests/rseq: Remove RSEQ_SKIP_FASTPATH code
> selftests/rseq: Implement rseq vm_vcpu_id field support
> selftests/rseq: x86: Template memory ordering and percpu access mode
> selftests/rseq: arm: Template memory ordering and percpu access mode
> selftests/rseq: arm64: Template memory ordering and percpu access mode
> selftests/rseq: mips: Template memory ordering and percpu access mode
> selftests/rseq: ppc: Template memory ordering and percpu access mode
> selftests/rseq: s390: Template memory ordering and percpu access mode
> selftests/rseq: riscv: Template memory ordering and percpu access mode
> selftests/rseq: Implement basic percpu ops vm_vcpu_id test
> selftests/rseq: Implement parametrized vm_vcpu_id test
> selftests/rseq: x86: Implement rseq_load_u32_u32
> selftests/rseq: Implement numa node id vs vm_vcpu_id invariant test
> selftests/rseq: parametrized test: Report/abort on negative cpu id
> tracing/rseq: Add mm_vcpu_id field to rseq_update
>
> fs/binfmt_elf.c | 5 +
> fs/exec.c | 6 +
> include/linux/cpumask.h | 86 ++
> include/linux/find.h | 123 +-
> include/linux/mm.h | 25 +
> include/linux/mm_types.h | 110 +-
> include/linux/sched.h | 9 +
> include/trace/events/rseq.h | 7 +-
> include/uapi/linux/auxvec.h | 2 +
> include/uapi/linux/rseq.h | 22 +
> init/Kconfig | 4 +
> kernel/fork.c | 11 +-
> kernel/ptrace.c | 2 +-
> kernel/rseq.c | 61 +-
> kernel/sched/core.c | 49 +
> kernel/sched/sched.h | 166 +++
> kernel/signal.c | 2 +
> lib/find_bit.c | 17 +-
> tools/include/linux/find.h | 9 +-
> tools/lib/find_bit.c | 17 +-
> tools/testing/selftests/rseq/.gitignore | 5 +
> tools/testing/selftests/rseq/Makefile | 20 +-
> .../testing/selftests/rseq/basic_numa_test.c | 117 ++
> .../selftests/rseq/basic_percpu_ops_test.c | 46 +-
> tools/testing/selftests/rseq/basic_test.c | 4 +
> tools/testing/selftests/rseq/compiler.h | 6 +
> tools/testing/selftests/rseq/param_test.c | 157 ++-
> tools/testing/selftests/rseq/rseq-abi.h | 22 +
> tools/testing/selftests/rseq/rseq-arm-bits.h | 505 +++++++
> tools/testing/selftests/rseq/rseq-arm.h | 701 +---------
> .../testing/selftests/rseq/rseq-arm64-bits.h | 392 ++++++
> tools/testing/selftests/rseq/rseq-arm64.h | 520 +------
> .../testing/selftests/rseq/rseq-bits-reset.h | 10 +
> .../selftests/rseq/rseq-bits-template.h | 39 +
> tools/testing/selftests/rseq/rseq-mips-bits.h | 462 +++++++
> tools/testing/selftests/rseq/rseq-mips.h | 646 +--------
> tools/testing/selftests/rseq/rseq-ppc-bits.h | 454 +++++++
> tools/testing/selftests/rseq/rseq-ppc.h | 617 +--------
> .../testing/selftests/rseq/rseq-riscv-bits.h | 410 ++++++
> tools/testing/selftests/rseq/rseq-riscv.h | 529 +-------
> tools/testing/selftests/rseq/rseq-s390-bits.h | 474 +++++++
> tools/testing/selftests/rseq/rseq-s390.h | 495 +------
> tools/testing/selftests/rseq/rseq-skip.h | 65 -
> tools/testing/selftests/rseq/rseq-x86-bits.h | 1036 ++++++++++++++
> tools/testing/selftests/rseq/rseq-x86.h | 1193 +----------------
> tools/testing/selftests/rseq/rseq.c | 86 +-
> tools/testing/selftests/rseq/rseq.h | 229 +++-
> .../testing/selftests/rseq/run_param_test.sh | 5 +
> 48 files changed, 5286 insertions(+), 4692 deletions(-)
> create mode 100644 tools/testing/selftests/rseq/basic_numa_test.c
> create mode 100644 tools/testing/selftests/rseq/rseq-arm-bits.h
> create mode 100644 tools/testing/selftests/rseq/rseq-arm64-bits.h
> create mode 100644 tools/testing/selftests/rseq/rseq-bits-reset.h
> create mode 100644 tools/testing/selftests/rseq/rseq-bits-template.h
> create mode 100644 tools/testing/selftests/rseq/rseq-mips-bits.h
> create mode 100644 tools/testing/selftests/rseq/rseq-ppc-bits.h
> create mode 100644 tools/testing/selftests/rseq/rseq-riscv-bits.h
> create mode 100644 tools/testing/selftests/rseq/rseq-s390-bits.h
> delete mode 100644 tools/testing/selftests/rseq/rseq-skip.h
> create mode 100644 tools/testing/selftests/rseq/rseq-x86-bits.h
>
--
Mathieu Desnoyers
EfficiOS Inc.
https://www.efficios.com
Use the ELF auxiliary vector AT_RSEQ_FEATURE_SIZE to detect the RSEQ
features supported by the kernel.
Signed-off-by: Mathieu Desnoyers <[email protected]>
---
tools/testing/selftests/rseq/rseq-abi.h | 5 ++
tools/testing/selftests/rseq/rseq.c | 68 ++++++++++++++++++++++---
tools/testing/selftests/rseq/rseq.h | 18 +++++--
3 files changed, 79 insertions(+), 12 deletions(-)
diff --git a/tools/testing/selftests/rseq/rseq-abi.h b/tools/testing/selftests/rseq/rseq-abi.h
index a8c44d9af71f..00ac846d85b0 100644
--- a/tools/testing/selftests/rseq/rseq-abi.h
+++ b/tools/testing/selftests/rseq/rseq-abi.h
@@ -146,6 +146,11 @@ struct rseq_abi {
* this thread.
*/
__u32 flags;
+
+ /*
+ * Flexible array member at end of structure, after last feature field.
+ */
+ char end[];
} __attribute__((aligned(4 * sizeof(__u64))));
#endif /* _RSEQ_ABI_H */
diff --git a/tools/testing/selftests/rseq/rseq.c b/tools/testing/selftests/rseq/rseq.c
index 986b9458efb2..20ea536d1012 100644
--- a/tools/testing/selftests/rseq/rseq.c
+++ b/tools/testing/selftests/rseq/rseq.c
@@ -28,6 +28,8 @@
#include <limits.h>
#include <dlfcn.h>
#include <stddef.h>
+#include <sys/auxv.h>
+#include <linux/auxvec.h>
#include "../kselftest.h"
#include "rseq.h"
@@ -36,20 +38,38 @@ static const ptrdiff_t *libc_rseq_offset_p;
static const unsigned int *libc_rseq_size_p;
static const unsigned int *libc_rseq_flags_p;
-/* Offset from the thread pointer to the rseq area. */
+/* Offset from the thread pointer to the rseq area. */
ptrdiff_t rseq_offset;
-/* Size of the registered rseq area. 0 if the registration was
- unsuccessful. */
+/*
+ * Size of the registered rseq area. 0 if the registration was
+ * unsuccessful.
+ */
unsigned int rseq_size = -1U;
/* Flags used during rseq registration. */
unsigned int rseq_flags;
+/*
+ * rseq feature size supported by the kernel. 0 if the registration was
+ * unsuccessful.
+ */
+unsigned int rseq_feature_size = -1U;
+
static int rseq_ownership;
+static int rseq_reg_success; /* At least one rseq registration has succeded. */
+
+/* Allocate a large area for the TLS. */
+#define RSEQ_THREAD_AREA_ALLOC_SIZE 1024
+
+/* Original struct rseq feature size is 20 bytes. */
+#define ORIG_RSEQ_FEATURE_SIZE 20
+
+/* Orignal struct rseq allocation size is 32 bytes. */
+#define ORIG_RSEQ_ALLOC_SIZE 32
static
-__thread struct rseq_abi __rseq_abi __attribute__((tls_model("initial-exec"))) = {
+__thread struct rseq_abi __rseq_abi __attribute__((tls_model("initial-exec"), aligned(RSEQ_THREAD_AREA_ALLOC_SIZE))) = {
.cpu_id = RSEQ_ABI_CPU_ID_UNINITIALIZED,
};
@@ -84,10 +104,18 @@ int rseq_register_current_thread(void)
/* Treat libc's ownership as a successful registration. */
return 0;
}
- rc = sys_rseq(&__rseq_abi, sizeof(struct rseq_abi), 0, RSEQ_SIG);
- if (rc)
+ rc = sys_rseq(&__rseq_abi, rseq_size, 0, RSEQ_SIG);
+ if (rc) {
+ if (RSEQ_READ_ONCE(rseq_reg_success)) {
+ /* Incoherent success/failure within process. */
+ abort();
+ }
+ rseq_size = 0;
+ rseq_feature_size = 0;
return -1;
+ }
assert(rseq_current_cpu_raw() >= 0);
+ RSEQ_WRITE_ONCE(rseq_reg_success, 1);
return 0;
}
@@ -99,12 +127,28 @@ int rseq_unregister_current_thread(void)
/* Treat libc's ownership as a successful unregistration. */
return 0;
}
- rc = sys_rseq(&__rseq_abi, sizeof(struct rseq_abi), RSEQ_ABI_FLAG_UNREGISTER, RSEQ_SIG);
+ rc = sys_rseq(&__rseq_abi, rseq_size, RSEQ_ABI_FLAG_UNREGISTER, RSEQ_SIG);
if (rc)
return -1;
return 0;
}
+static
+unsigned int get_rseq_feature_size(void)
+{
+ unsigned long auxv_rseq_feature_size, auxv_rseq_align;
+
+ auxv_rseq_align = getauxval(AT_RSEQ_ALIGN);
+ assert(!auxv_rseq_align || auxv_rseq_align <= RSEQ_THREAD_AREA_ALLOC_SIZE);
+
+ auxv_rseq_feature_size = getauxval(AT_RSEQ_FEATURE_SIZE);
+ assert(!auxv_rseq_feature_size || auxv_rseq_feature_size <= RSEQ_THREAD_AREA_ALLOC_SIZE);
+ if (auxv_rseq_feature_size)
+ return auxv_rseq_feature_size;
+ else
+ return ORIG_RSEQ_FEATURE_SIZE;
+}
+
static __attribute__((constructor))
void rseq_init(void)
{
@@ -116,14 +160,21 @@ void rseq_init(void)
rseq_offset = *libc_rseq_offset_p;
rseq_size = *libc_rseq_size_p;
rseq_flags = *libc_rseq_flags_p;
+ rseq_feature_size = get_rseq_feature_size();
+ if (rseq_feature_size > rseq_size)
+ rseq_feature_size = rseq_size;
return;
}
if (!rseq_available())
return;
rseq_ownership = 1;
rseq_offset = (void *)&__rseq_abi - rseq_thread_pointer();
- rseq_size = sizeof(struct rseq_abi);
rseq_flags = 0;
+ rseq_feature_size = get_rseq_feature_size();
+ if (rseq_feature_size == ORIG_RSEQ_FEATURE_SIZE)
+ rseq_size = ORIG_RSEQ_ALLOC_SIZE;
+ else
+ rseq_size = RSEQ_THREAD_AREA_ALLOC_SIZE;
}
static __attribute__((destructor))
@@ -133,6 +184,7 @@ void rseq_exit(void)
return;
rseq_offset = 0;
rseq_size = -1U;
+ rseq_feature_size = -1U;
rseq_ownership = 0;
}
diff --git a/tools/testing/selftests/rseq/rseq.h b/tools/testing/selftests/rseq/rseq.h
index 6f7513384bf5..95adc1e1b0db 100644
--- a/tools/testing/selftests/rseq/rseq.h
+++ b/tools/testing/selftests/rseq/rseq.h
@@ -47,14 +47,24 @@
#include "rseq-thread-pointer.h"
-/* Offset from the thread pointer to the rseq area. */
+/* Offset from the thread pointer to the rseq area. */
extern ptrdiff_t rseq_offset;
-/* Size of the registered rseq area. 0 if the registration was
- unsuccessful. */
+
+/*
+ * Size of the registered rseq area. 0 if the registration was
+ * unsuccessful.
+ */
extern unsigned int rseq_size;
-/* Flags used during rseq registration. */
+
+/* Flags used during rseq registration. */
extern unsigned int rseq_flags;
+/*
+ * rseq feature size supported by the kernel. 0 if the registration was
+ * unsuccessful.
+ */
+extern unsigned int rseq_feature_size;
+
static inline struct rseq_abi *rseq_get_abi(void)
{
return (struct rseq_abi *) ((uintptr_t) rseq_thread_pointer() + rseq_offset);
--
2.25.1
On Wed, Sep 21, 2022 at 03:54:18PM -0400, Mathieu Desnoyers wrote:
> On 2022-09-21 15:24, Mathieu Desnoyers wrote:
> > Extend the rseq ABI to expose a NUMA node ID and a vm_vcpu_id field.
> >
> > The NUMA node ID field allows implementing a faster getcpu(2) in libc.
> >
> > The virtual cpu id allows ideal scaling (down or up) of user-space
> > per-cpu data structures. The virtual cpu ids allocated within a memory
> > space are tracked by the scheduler, which takes into account the number
> > of concurrently running threads, thus implicitly considering the number
> > of threads, the cpu affinity, the cpusets applying to those threads, and
> > the number of logical cores on the system.
> >
> > This series is based on the v5.19 tag.
>
> Hi Peter,
>
> I'm having MTA issues at the moment. I will resend the series as soon as I
> can get hold of my sysadmin.
It landed in my inbox and Lore seems to have received a copy too; as
per:
https://lkml.kernel.org/r/[email protected]
So I'm thinking you did manage to send out mail and all is well.
I'll try and have a look later today.
On 2022-09-22 04:10, Peter Zijlstra wrote:
> On Wed, Sep 21, 2022 at 03:54:18PM -0400, Mathieu Desnoyers wrote:
[...]
>> Hi Peter,
>>
>> I'm having MTA issues at the moment. I will resend the series as soon as I
>> can get hold of my sysadmin.
>
> It landed in my inbox and Lore seems to have received a copy too; as
> per:
>
> https://lkml.kernel.org/r/[email protected]
>
> So I'm thinking you did manage to send out mail and all is well.
>
> I'll try and have a look later today.
AFAIU my ISP's MTA only sent the first 7 emails in the series, and the
rest are nowhere to be seen.
I've hopefully managed to fix my issues now. Let me try to resend the
whole series. (without RFC tag this time)
Thanks,
Mathieu
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Mathieu Desnoyers
EfficiOS Inc.
https://www.efficios.com