linux/scripts/gdb
Florian Rommel 40eea5abbb scripts/gdb: fix detection of current CPU in KGDB
Directly read the current CPU number from the kgdb_active variable.

Before, the active CPU was obtained through the current task, which
required searching the task list for the pid of GDB's selected thread. 
Obtaining the pid was buggy: GDB may use selected_thread().ptid[1] (LWPID)
instead of .ptid[2] (TID) to store the threads pid; see
https://sourceware.org/gdb/current/onlinedocs/gdb.html/Threads-In-Python.html
As a result, the detection could return the wrong CPU number, leading to
incorrect results for $lx_per_cpu and $lx_current.

As a side effect, the patch significantly speeds up $lx_per_cpu and
$lx_current in KGDB by avoiding the task-list iteration.

Link: https://lkml.kernel.org/r/20240425153501.749966-5-mail@florommel.de
Signed-off-by: Florian Rommel <mail@florommel.de>
Cc: Andrew Jones <ajones@ventanamicro.com>
Cc: Deepak Gupta <debug@rivosinc.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Cc: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-08 08:41:28 -07:00
..
linux scripts/gdb: fix detection of current CPU in KGDB 2024-05-08 08:41:28 -07:00
Makefile treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
vmlinux-gdb.py scripts/gdb/vmalloc: add vmallocinfo support 2023-08-21 13:46:23 -07:00