diff options
author | Chris Metcalf <cmetcalf@ezchip.com> | 2016-01-25 23:05:34 +0300 |
---|---|---|
committer | Chris Metcalf <cmetcalf@ezchip.com> | 2016-03-02 23:19:44 +0300 |
commit | 77ef8f5177599efd0cedeb52c1950c1bd73fa5e3 (patch) | |
tree | b6091bf407bc008da5fd6e68d4eaca4d543efe58 /arch | |
parent | 81f70ba233d5f660e1ea5fe23260ee323af5d53a (diff) | |
download | linux-77ef8f5177599efd0cedeb52c1950c1bd73fa5e3.tar.xz |
tile kgdb: fix bug in copy to gdb regs, and optimize memset
David Binderman pointed out that we were doing a full memset()
of the gdb register buffer and then doing a memcpy() to it that
was almost as big. This commit optimizes that by only doing a
memset() of the registers that are intended to be zero.
While making this change I noticed that we were not copying the
link register (LR, number 55) due to a fencepost error in commit
f419e6f63c5a ("arch: tile: kernel: kgdb.c: Use memcpy() instead of
pointer copy one by one"), and I've corrected that as well.
Reported-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/tile/kernel/kgdb.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/arch/tile/kernel/kgdb.c b/arch/tile/kernel/kgdb.c index a506c2c28943..6ad99925900e 100644 --- a/arch/tile/kernel/kgdb.c +++ b/arch/tile/kernel/kgdb.c @@ -126,15 +126,15 @@ void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *task) { struct pt_regs *thread_regs; + const int NGPRS = TREG_LAST_GPR + 1; if (task == NULL) return; - /* Initialize to zero. */ - memset(gdb_regs, 0, NUMREGBYTES); - thread_regs = task_pt_regs(task); - memcpy(gdb_regs, thread_regs, TREG_LAST_GPR * sizeof(unsigned long)); + memcpy(gdb_regs, thread_regs, NGPRS * sizeof(unsigned long)); + memset(&gdb_regs[NGPRS], 0, + (TILEGX_PC_REGNUM - NGPRS) * sizeof(unsigned long)); gdb_regs[TILEGX_PC_REGNUM] = thread_regs->pc; gdb_regs[TILEGX_FAULTNUM_REGNUM] = thread_regs->faultnum; } |