Re: [PATCH v2 05/16] powerpc/watchpoint: Provide DAWR number to set_dawr

From: Christophe Leroy
Date: Wed Apr 01 2020 - 03:03:13 EST




Le 01/04/2020 Ã 08:12, Ravi Bangoria a ÃcritÂ:
Introduce new parameter 'nr' to set_dawr() which indicates which DAWR
should be programed.

Signed-off-by: Ravi Bangoria <ravi.bangoria@xxxxxxxxxxxxx>
---
arch/powerpc/include/asm/hw_breakpoint.h | 4 ++--
arch/powerpc/kernel/dawr.c | 15 ++++++++++-----
arch/powerpc/kernel/process.c | 2 +-
3 files changed, 13 insertions(+), 8 deletions(-)

diff --git a/arch/powerpc/include/asm/hw_breakpoint.h b/arch/powerpc/include/asm/hw_breakpoint.h
index 518b41eef924..62549007c87a 100644
--- a/arch/powerpc/include/asm/hw_breakpoint.h
+++ b/arch/powerpc/include/asm/hw_breakpoint.h
@@ -104,10 +104,10 @@ static inline bool dawr_enabled(void)
{
return dawr_force_enable;
}
-int set_dawr(struct arch_hw_breakpoint *brk);
+int set_dawr(struct arch_hw_breakpoint *brk, int nr);

Wondering if it wouldn't make more sense to have nr as first argument.

Christophe

#else
static inline bool dawr_enabled(void) { return false; }
-static inline int set_dawr(struct arch_hw_breakpoint *brk) { return -1; }
+static inline int set_dawr(struct arch_hw_breakpoint *brk, int nr) { return -1; }
#endif
#endif /* __KERNEL__ */
diff --git a/arch/powerpc/kernel/dawr.c b/arch/powerpc/kernel/dawr.c
index e91b613bf137..311e51ee09f4 100644
--- a/arch/powerpc/kernel/dawr.c
+++ b/arch/powerpc/kernel/dawr.c
@@ -16,7 +16,7 @@
bool dawr_force_enable;
EXPORT_SYMBOL_GPL(dawr_force_enable);
-int set_dawr(struct arch_hw_breakpoint *brk)
+int set_dawr(struct arch_hw_breakpoint *brk, int nr)
{
unsigned long dawr, dawrx, mrd;
@@ -39,15 +39,20 @@ int set_dawr(struct arch_hw_breakpoint *brk)
if (ppc_md.set_dawr)
return ppc_md.set_dawr(dawr, dawrx);
- mtspr(SPRN_DAWR0, dawr);
- mtspr(SPRN_DAWRX0, dawrx);
+ if (nr == 0) {
+ mtspr(SPRN_DAWR0, dawr);
+ mtspr(SPRN_DAWRX0, dawrx);
+ } else {
+ mtspr(SPRN_DAWR1, dawr);
+ mtspr(SPRN_DAWRX1, dawrx);
+ }
return 0;
}
static void set_dawr_cb(void *info)
{
- set_dawr(info);
+ set_dawr(info, 0);
}
static ssize_t dawr_write_file_bool(struct file *file,
@@ -60,7 +65,7 @@ static ssize_t dawr_write_file_bool(struct file *file,
/* Send error to user if they hypervisor won't allow us to write DAWR */
if (!dawr_force_enable &&
firmware_has_feature(FW_FEATURE_LPAR) &&
- set_dawr(&null_brk) != H_SUCCESS)
+ set_dawr(&null_brk, 0) != H_SUCCESS)
return -ENODEV;
rc = debugfs_write_file_bool(file, user_buf, count, ppos);
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 110db94cdf3c..b548a584e465 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -799,7 +799,7 @@ void __set_breakpoint(struct arch_hw_breakpoint *brk)
if (dawr_enabled())
// Power8 or later
- set_dawr(brk);
+ set_dawr(brk, 0);
else if (IS_ENABLED(CONFIG_PPC_8xx))
set_breakpoint_8xx(brk);
else if (!cpu_has_feature(CPU_FTR_ARCH_207S))