cxl: Add tracepoints
This patch adds tracepoints throughout the cxl driver, which can provide
insight into:
- Context lifetimes
- Commands sent to the PSL and AFU and their completion status
- Segment and page table misses and their resolution
- PSL and AFU interrupts
- slbia calls from the powerpc copro_fault code
These tracepoints are mostly intended to aid in debugging (particularly
for new AFU designs), and may be useful standalone or in conjunction
with hardware traces collected by the PSL (read out via the trace
interface in debugfs) and AFUs.
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
diff --git a/drivers/misc/cxl/native.c b/drivers/misc/cxl/native.c
index 0f24fa5..29185fc 100644
--- a/drivers/misc/cxl/native.c
+++ b/drivers/misc/cxl/native.c
@@ -18,24 +18,28 @@
#include <misc/cxl.h>
#include "cxl.h"
+#include "trace.h"
static int afu_control(struct cxl_afu *afu, u64 command,
u64 result, u64 mask, bool enabled)
{
u64 AFU_Cntl = cxl_p2n_read(afu, CXL_AFU_Cntl_An);
unsigned long timeout = jiffies + (HZ * CXL_TIMEOUT);
+ int rc = 0;
spin_lock(&afu->afu_cntl_lock);
pr_devel("AFU command starting: %llx\n", command);
+ trace_cxl_afu_ctrl(afu, command);
+
cxl_p2n_write(afu, CXL_AFU_Cntl_An, AFU_Cntl | command);
AFU_Cntl = cxl_p2n_read(afu, CXL_AFU_Cntl_An);
while ((AFU_Cntl & mask) != result) {
if (time_after_eq(jiffies, timeout)) {
dev_warn(&afu->dev, "WARNING: AFU control timed out!\n");
- spin_unlock(&afu->afu_cntl_lock);
- return -EBUSY;
+ rc = -EBUSY;
+ goto out;
}
pr_devel_ratelimited("AFU control... (0x%.16llx)\n",
AFU_Cntl | command);
@@ -44,9 +48,11 @@
};
pr_devel("AFU command complete: %llx\n", command);
afu->enabled = enabled;
+out:
+ trace_cxl_afu_ctrl_done(afu, command, rc);
spin_unlock(&afu->afu_cntl_lock);
- return 0;
+ return rc;
}
static int afu_enable(struct cxl_afu *afu)
@@ -91,6 +97,9 @@
u64 dsisr, dar;
u64 start, end;
unsigned long timeout = jiffies + (HZ * CXL_TIMEOUT);
+ int rc = 0;
+
+ trace_cxl_psl_ctrl(afu, CXL_PSL_SCNTL_An_Pc);
pr_devel("PSL purge request\n");
@@ -107,7 +116,8 @@
== CXL_PSL_SCNTL_An_Ps_Pending) {
if (time_after_eq(jiffies, timeout)) {
dev_warn(&afu->dev, "WARNING: PSL Purge timed out!\n");
- return -EBUSY;
+ rc = -EBUSY;
+ goto out;
}
dsisr = cxl_p2n_read(afu, CXL_PSL_DSISR_An);
pr_devel_ratelimited("PSL purging... PSL_CNTL: 0x%.16llx PSL_DSISR: 0x%.16llx\n", PSL_CNTL, dsisr);
@@ -128,7 +138,9 @@
cxl_p1n_write(afu, CXL_PSL_SCNTL_An,
PSL_CNTL & ~CXL_PSL_SCNTL_An_Pc);
- return 0;
+out:
+ trace_cxl_psl_ctrl_done(afu, CXL_PSL_SCNTL_An_Pc, rc);
+ return rc;
}
static int spa_max_procs(int spa_size)
@@ -279,6 +291,9 @@
{
u64 state;
unsigned long timeout = jiffies + (HZ * CXL_TIMEOUT);
+ int rc = 0;
+
+ trace_cxl_llcmd(ctx, cmd);
WARN_ON(!ctx->afu->enabled);
@@ -290,12 +305,14 @@
while (1) {
if (time_after_eq(jiffies, timeout)) {
dev_warn(&ctx->afu->dev, "WARNING: Process Element Command timed out!\n");
- return -EBUSY;
+ rc = -EBUSY;
+ goto out;
}
state = be64_to_cpup(ctx->afu->sw_command_status);
if (state == ~0ULL) {
pr_err("cxl: Error adding process element to AFU\n");
- return -1;
+ rc = -1;
+ goto out;
}
if ((state & (CXL_SPA_SW_CMD_MASK | CXL_SPA_SW_STATE_MASK | CXL_SPA_SW_LINK_MASK)) ==
(cmd | (cmd >> 16) | ctx->pe))
@@ -310,7 +327,9 @@
schedule();
}
- return 0;
+out:
+ trace_cxl_llcmd_done(ctx, cmd, rc);
+ return rc;
}
static int add_process_element(struct cxl_context *ctx)
@@ -630,6 +649,8 @@
int cxl_detach_process(struct cxl_context *ctx)
{
+ trace_cxl_detach(ctx);
+
if (ctx->afu->current_mode == CXL_MODE_DEDICATED)
return detach_process_native_dedicated(ctx);
@@ -668,6 +689,7 @@
int cxl_ack_irq(struct cxl_context *ctx, u64 tfc, u64 psl_reset_mask)
{
+ trace_cxl_psl_irq_ack(ctx, tfc);
if (tfc)
cxl_p2n_write(ctx->afu, CXL_PSL_TFC_An, tfc);
if (psl_reset_mask)