Up until this patch, each of the per CPU buffers appear as a separate
ftrace-ramoops-N file. In this patch we merge all the zones into one and
populate the ftrace-ramoops-0 file.
Signed-off-by: Joel Fernandes <joe...@google.com>
---
fs/pstore/ram.c | 91 +++++++++++++++++++++++++++++++++++++++++++++++++++++----
1 file changed, 85 insertions(+), 6 deletions(-)
diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c
index 2e29d6b..cc37ec4 100644
--- a/fs/pstore/ram.c
+++ b/fs/pstore/ram.c
@@ -181,6 +181,53 @@ static bool prz_ok(struct persistent_ram_zone *prz)
persistent_ram_ecc_string(prz, NULL, 0));
}
+static void ftrace_old_log_combine(struct persistent_ram_zone *dest,
+ struct persistent_ram_zone *src)
+{
+ int dest_size, src_size, total, destoff, srcoff, i = 0, j = 0, k = 0;
+ void *mbuf;
+ struct pstore_ftrace_record *drec, *srec, *mrec;
+ int record_size = sizeof(struct pstore_ftrace_record);
+
+ destoff = dest->old_log_size % record_size;
+ dest_size = dest->old_log_size - destoff;
+
+ srcoff = src->old_log_size % record_size;
+ src_size = src->old_log_size - srcoff;
+
+ total = dest_size + src_size;
+ mbuf = kmalloc(total, GFP_KERNEL);
+
+ drec = (struct pstore_ftrace_record *)(dest->old_log + destoff);
+ srec = (struct pstore_ftrace_record *)(src->old_log + srcoff);
+ mrec = (struct pstore_ftrace_record *)(mbuf);
+
+ while (dest_size > 0 && src_size > 0) {
+ if (pstore_ftrace_read_timestamp(&drec[i]) <
+ pstore_ftrace_read_timestamp(&srec[j])) {
+ mrec[k++] = drec[i++];
+ dest_size -= record_size;
+ } else {
+ mrec[k++] = srec[j++];
+ src_size -= record_size;
+ }
+ }
+
+ while (dest_size > 0) {
+ mrec[k++] = drec[i++];
+ dest_size -= record_size;
+ }
+
+ while (src_size > 0) {
+ mrec[k++] = srec[j++];
+ src_size -= record_size;
+ }
+
+ kfree(dest->old_log);
+ dest->old_log = mbuf;
+ dest->old_log_size = total;
+}
+
static ssize_t ramoops_pstore_read(u64 *id, enum pstore_type_id *type,
int *count, struct timespec *time,
char **buf, bool *compressed,
@@ -190,7 +237,7 @@ static ssize_t ramoops_pstore_read(u64 *id, enum
pstore_type_id *type,
ssize_t size;
struct ramoops_context *cxt = psi->data;
struct persistent_ram_zone *prz = NULL;
- int header_length = 0;
+ int header_length = 0, free_prz = 0;
/* Ramoops headers provide time stamps for PSTORE_TYPE_DMESG, but
* PSTORE_TYPE_CONSOLE and PSTORE_TYPE_FTRACE don't currently have
@@ -221,13 +268,39 @@ static ssize_t ramoops_pstore_read(u64 *id, enum
pstore_type_id *type,
prz = ramoops_get_next_prz(&cxt->cprz, &cxt->console_read_cnt,
1, id, type, PSTORE_TYPE_CONSOLE, 0);
if (!prz_ok(prz)) {
- int max = (cxt->flags & FTRACE_PER_CPU) ? nr_cpu_ids : 1;
- while (cxt->ftrace_read_cnt < max && !prz) {
+ if (!(cxt->flags & FTRACE_PER_CPU)) {
prz = ramoops_get_next_prz(cxt->fprzs,
- &cxt->ftrace_read_cnt, max, id, type,
+ &cxt->ftrace_read_cnt, 1, id, type,
PSTORE_TYPE_FTRACE, 0);
- if (!prz_ok(prz))
- continue;
+ } else {
+ /*
+ * Build a new dummy zone which combines all the
+ * per-cpu zones and accumulate the zone data and ecc
+ * info.
+ */
+ int max;
+ struct persistent_ram_zone *tmp_prz, *prz_next;
+
+ tmp_prz = kzalloc(sizeof(struct persistent_ram_zone),
+ GFP_KERNEL);
+ max = nr_cpu_ids;
+ while (cxt->ftrace_read_cnt < max) {
+ prz_next = ramoops_get_next_prz(cxt->fprzs,
+ &cxt->ftrace_read_cnt, max, id,
+ type, PSTORE_TYPE_FTRACE, 0);
+
+ if (!prz_ok(prz_next))
+ continue;
+
+ tmp_prz->ecc_info = prz_next->ecc_info;
+ tmp_prz->corrected_bytes +=
+ prz_next->corrected_bytes;
+ tmp_prz->bad_blocks += prz_next->bad_blocks;
+ ftrace_old_log_combine(tmp_prz, prz_next);
+ }
+ *id = 0;
+ prz = tmp_prz;
+ free_prz = 1;
}
}
@@ -247,6 +320,12 @@ static ssize_t ramoops_pstore_read(u64 *id, enum
pstore_type_id *type,
return -ENOMEM;
memcpy(*buf, (char *)persistent_ram_old(prz) + header_length, size);
+
+ if (free_prz) {
+ kfree(prz->old_log);
+ kfree(prz);
+ }
+
persistent_ram_ecc_string(prz, *buf + size, *ecc_notice_size + 1);
return size;
--
2.7.4
