[Qemu-devel] [PATCH] trace: Trace SCSI request lifecycle

[Stefan Hajnoczi]

This patch adds trace events for SCSI request allocation, freeing, CDB
parsing, read, and write.  These trace events can be used to instrument
the SCSI request lifecycle.

Signed-off-by: Stefan Hajnoczi <address@hidden>
---
 hw/scsi-bus.c  |    5 +++++
 hw/scsi-disk.c |    9 +++++++++
 trace-events   |   11 +++++++++++
 3 files changed, 25 insertions(+), 0 deletions(-)

diff --git a/hw/scsi-bus.c b/hw/scsi-bus.c
index 5a3fd4b..0228d4f 100644
--- a/hw/scsi-bus.c
+++ b/hw/scsi-bus.c
@@ -4,6 +4,7 @@
 #include "scsi-defs.h"
 #include "qdev.h"
 #include "blockdev.h"
+#include "trace.h"
 
 static struct BusInfo scsi_bus_info = {
     .name  = "SCSI",
@@ -145,6 +146,8 @@ SCSIRequest *scsi_req_alloc(size_t size, SCSIDevice *d, 
uint32_t tag, uint32_t l
     req->status = -1;
     req->enqueued = true;
     QTAILQ_INSERT_TAIL(&d->requests, req, next);
+
+    trace_scsi_req_alloc(d, tag, lun, req);
     return req;
 }
 
@@ -172,6 +175,7 @@ void scsi_req_free(SCSIRequest *req)
 {
     scsi_req_dequeue(req);
     qemu_free(req);
+    trace_scsi_req_free(req);
 }
 
 static int scsi_req_length(SCSIRequest *req, uint8_t *cmd)
@@ -395,6 +399,7 @@ int scsi_req_parse(SCSIRequest *req, uint8_t *buf)
     memcpy(req->cmd.buf, buf, req->cmd.len);
     scsi_req_xfer_mode(req);
     req->cmd.lba = scsi_req_lba(req);
+    trace_scsi_req_parse(req, req->cmd.len, req->cmd.lba, req->cmd.buf[0]);
     return 0;
 }
 
diff --git a/hw/scsi-disk.c b/hw/scsi-disk.c
index dc71957..c7a3f2a 100644
--- a/hw/scsi-disk.c
+++ b/hw/scsi-disk.c
@@ -37,6 +37,7 @@ do { fprintf(stderr, "scsi-disk: " fmt , ## __VA_ARGS__); } 
while (0)
 #include "scsi-defs.h"
 #include "sysemu.h"
 #include "blockdev.h"
+#include "trace.h"
 
 #define SCSI_DMA_BUF_SIZE    131072
 #define SCSI_MAX_INQUIRY_LEN 256
@@ -136,6 +137,8 @@ static void scsi_read_complete(void * opaque, int ret)
     SCSIDiskReq *r = (SCSIDiskReq *)opaque;
     int n;
 
+    trace_scsi_read_complete(r, ret);
+
     r->req.aiocb = NULL;
 
     if (ret) {
@@ -158,6 +161,8 @@ static void scsi_read_request(SCSIDiskReq *r)
     SCSIDiskState *s = DO_UPCAST(SCSIDiskState, qdev, r->req.dev);
     uint32_t n;
 
+    trace_scsi_read_request(r, r->sector, r->sector_count);
+
     if (r->sector_count == (uint32_t)-1) {
         DPRINTF("Read buf_len=%zd\n", r->iov.iov_len);
         r->sector_count = 0;
@@ -240,6 +245,8 @@ static void scsi_write_complete(void * opaque, int ret)
     uint32_t len;
     uint32_t n;
 
+    trace_scsi_write_complete(r, ret);
+
     r->req.aiocb = NULL;
 
     if (ret) {
@@ -269,6 +276,8 @@ static void scsi_write_request(SCSIDiskReq *r)
     SCSIDiskState *s = DO_UPCAST(SCSIDiskState, qdev, r->req.dev);
     uint32_t n;
 
+    trace_scsi_write_request(r, r->sector, r->iov.iov_len);
+
     n = r->iov.iov_len / 512;
     if (n) {
         qemu_iovec_init_external(&r->qiov, &r->iov, 1);
diff --git a/trace-events b/trace-events
index 947f8b0..7069628 100644
--- a/trace-events
+++ b/trace-events
@@ -189,3 +189,14 @@ disable sun4m_iommu_mem_writel_pgflush(uint32_t val) "page 
flush %x"
 disable sun4m_iommu_page_get_flags(uint64_t pa, uint64_t iopte, uint32_t ret) 
"get flags addr %"PRIx64" => pte %"PRIx64", *pte = %x"
 disable sun4m_iommu_translate_pa(uint64_t addr, uint64_t pa, uint32_t iopte) 
"xlate dva %"PRIx64" => pa %"PRIx64" iopte = %x"
 disable sun4m_iommu_bad_addr(uint64_t addr) "bad addr %"PRIx64""
+
+# hw/scsi-bus.c
+disable scsi_req_alloc(void *dev, uint32_t tag, uint32_t lun, void *req) "dev 
%p tag %#x lun %#x req %p"
+disable scsi_req_free(void *req) "req %p"
+disable scsi_req_parse(void *req, int len, uint64_t lba, uint8_t cmd) "req %p 
len %d lba %"PRIu64" cmd %#x"
+
+# hw/scsi-disk.c
+disable scsi_read_request(void *req, uint64_t sector, uint32_t sector_count) 
"req %p sector %"PRIu64" sector_count %u"
+disable scsi_read_complete(void *req, int ret) "req %p ret %d"
+disable scsi_write_request(void *req, uint64_t sector, size_t len) "req %p 
sector %"PRIu64" len %zu"
+disable scsi_write_complete(void *req, int ret) "req %p ret %d"
-- 
1.7.2.3