perf header: Encapsulate read and swap

Most callers of readn() in perf header read either a 32 or a 64 bits
number, error check it and swap it, if necessary.

Create do_read_u32 and do_read_u64 to simplify these use cases.

Signed-off-by: David Carrillo-Cisneros <davidcc@google.com>
Acked-by: David Ahern <dsahern@gmail.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Simon Que <sque@chromium.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20170718042549.145161-2-davidcc@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index 76ed7d03e500fa246776689e85df53a89171f79a..24e842c0202783d33dcc07fcc80f9b3c68f59201 100644 (file)
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -119,25 +119,54 @@ static int do_write_string(int fd, const char *str)
        return write_padded(fd, str, olen, len);
 }
 
+static int __do_read(int fd, void *addr, ssize_t size)
+{
+       ssize_t ret = readn(fd, addr, size);
+
+       if (ret != size)
+               return ret < 0 ? (int)ret : -1;
+       return 0;
+}
+
+static int do_read_u32(int fd, struct perf_header *ph, u32 *addr)
+{
+       int ret;
+
+       ret = __do_read(fd, addr, sizeof(*addr));
+       if (ret)
+               return ret;
+
+       if (ph->needs_swap)
+               *addr = bswap_32(*addr);
+       return 0;
+}
+
+static int do_read_u64(int fd, struct perf_header *ph, u64 *addr)
+{
+       int ret;
+
+       ret = __do_read(fd, addr, sizeof(*addr));
+       if (ret)
+               return ret;
+
+       if (ph->needs_swap)
+               *addr = bswap_64(*addr);
+       return 0;
+}
+
 static char *do_read_string(int fd, struct perf_header *ph)
 {
-       ssize_t sz, ret;
        u32 len;
        char *buf;
 
-       sz = readn(fd, &len, sizeof(len));
-       if (sz < (ssize_t)sizeof(len))
+       if (do_read_u32(fd, ph, &len))
                return NULL;
 
-       if (ph->needs_swap)
-               len = bswap_32(len);
-
        buf = malloc(len);
        if (!buf)
                return NULL;
 
-       ret = readn(fd, buf, len);
-       if (ret == (ssize_t)len) {
+       if (!__do_read(fd, buf, len)) {
                /*
                 * strings are padded by zeroes
                 * thus the actual strlen of buf
@@ -1188,24 +1217,15 @@ read_event_desc(struct perf_header *ph, int fd)
        u64 *id;
        void *buf = NULL;
        u32 nre, sz, nr, i, j;
-       ssize_t ret;
        size_t msz;
 
        /* number of events */
-       ret = readn(fd, &nre, sizeof(nre));
-       if (ret != (ssize_t)sizeof(nre))
+       if (do_read_u32(fd, ph, &nre))
                goto error;
 
-       if (ph->needs_swap)
-               nre = bswap_32(nre);
-
-       ret = readn(fd, &sz, sizeof(sz));
-       if (ret != (ssize_t)sizeof(sz))
+       if (do_read_u32(fd, ph, &sz))
                goto error;
 
-       if (ph->needs_swap)
-               sz = bswap_32(sz);
-
        /* buffer to hold on file attr struct */
        buf = malloc(sz);
        if (!buf)
@@ -1227,8 +1247,7 @@ read_event_desc(struct perf_header *ph, int fd)
                 * must read entire on-file attr struct to
                 * sync up with layout.
                 */
-               ret = readn(fd, buf, sz);
-               if (ret != (ssize_t)sz)
+               if (__do_read(fd, buf, sz))
                        goto error;
 
                if (ph->needs_swap)
@@ -1236,16 +1255,15 @@ read_event_desc(struct perf_header *ph, int fd)
 
                memcpy(&evsel->attr, buf, msz);
 
-               ret = readn(fd, &nr, sizeof(nr));
-               if (ret != (ssize_t)sizeof(nr))
+               if (do_read_u32(fd, ph, &nr))
                        goto error;
 
-               if (ph->needs_swap) {
-                       nr = bswap_32(nr);
+               if (ph->needs_swap)
                        evsel->needs_swap = true;
-               }
 
                evsel->name = do_read_string(fd, ph);
+               if (!evsel->name)
+                       goto error;
 
                if (!nr)
                        continue;
@@ -1257,11 +1275,8 @@ read_event_desc(struct perf_header *ph, int fd)
                evsel->id = id;
 
                for (j = 0 ; j < nr; j++) {
-                       ret = readn(fd, id, sizeof(*id));
-                       if (ret != (ssize_t)sizeof(*id))
+                       if (do_read_u64(fd, ph, id))
                                goto error;
-                       if (ph->needs_swap)
-                               *id = bswap_64(*id);
                        id++;
                }
        }
@@ -1641,26 +1656,18 @@ static int process_nrcpus(struct perf_file_section *section __maybe_unused,
                          struct perf_header *ph, int fd,
                          void *data __maybe_unused)
 {
-       ssize_t ret;
-       u32 nr;
-
-       ret = readn(fd, &nr, sizeof(nr));
-       if (ret != sizeof(nr))
-               return -1;
-
-       if (ph->needs_swap)
-               nr = bswap_32(nr);
-
-       ph->env.nr_cpus_avail = nr;
-
-       ret = readn(fd, &nr, sizeof(nr));
-       if (ret != sizeof(nr))
-               return -1;
+       int ret;
+       u32 nr_cpus_avail, nr_cpus_online;
 
-       if (ph->needs_swap)
-               nr = bswap_32(nr);
+       ret = do_read_u32(fd, ph, &nr_cpus_avail);
+       if (ret)
+               return ret;
 
-       ph->env.nr_cpus_online = nr;
+       ret = do_read_u32(fd, ph, &nr_cpus_online);
+       if (ret)
+               return ret;
+       ph->env.nr_cpus_avail = (int)nr_cpus_avail;
+       ph->env.nr_cpus_online = (int)nr_cpus_online;
        return 0;
 }
 
@@ -1684,17 +1691,13 @@ static int process_total_mem(struct perf_file_section *section __maybe_unused,
                             struct perf_header *ph, int fd,
                             void *data __maybe_unused)
 {
-       uint64_t mem;
-       ssize_t ret;
+       u64 total_mem;
+       int ret;
 
-       ret = readn(fd, &mem, sizeof(mem));
-       if (ret != sizeof(mem))
+       ret = do_read_u64(fd, ph, &total_mem);
+       if (ret)
                return -1;
-
-       if (ph->needs_swap)
-               mem = bswap_64(mem);
-
-       ph->env.total_mem = mem;
+       ph->env.total_mem = (unsigned long long)total_mem;
        return 0;
 }
 
@@ -1754,17 +1757,12 @@ static int process_cmdline(struct perf_file_section *section,
                           struct perf_header *ph, int fd,
                           void *data __maybe_unused)
 {
-       ssize_t ret;
        char *str, *cmdline = NULL, **argv = NULL;
        u32 nr, i, len = 0;
 
-       ret = readn(fd, &nr, sizeof(nr));
-       if (ret != sizeof(nr))
+       if (do_read_u32(fd, ph, &nr))
                return -1;
 
-       if (ph->needs_swap)
-               nr = bswap_32(nr);
-
        ph->env.nr_cmdline = nr;
 
        cmdline = zalloc(section->size + nr + 1);
@@ -1799,7 +1797,6 @@ static int process_cpu_topology(struct perf_file_section *section,
                                struct perf_header *ph, int fd,
                                void *data __maybe_unused)
 {
-       ssize_t ret;
        u32 nr, i;
        char *str;
        struct strbuf sb;
@@ -1810,13 +1807,9 @@ static int process_cpu_topology(struct perf_file_section *section,
        if (!ph->env.cpu)
                return -1;
 
-       ret = readn(fd, &nr, sizeof(nr));
-       if (ret != sizeof(nr))
+       if (do_read_u32(fd, ph, &nr))
                goto free_cpu;
 
-       if (ph->needs_swap)
-               nr = bswap_32(nr);
-
        ph->env.nr_sibling_cores = nr;
        size += sizeof(u32);
        if (strbuf_init(&sb, 128) < 0)
@@ -1835,13 +1828,9 @@ static int process_cpu_topology(struct perf_file_section *section,
        }
        ph->env.sibling_cores = strbuf_detach(&sb, NULL);
 
-       ret = readn(fd, &nr, sizeof(nr));
-       if (ret != sizeof(nr))
+       if (do_read_u32(fd, ph, &nr))
                return -1;
 
-       if (ph->needs_swap)
-               nr = bswap_32(nr);
-
        ph->env.nr_sibling_threads = nr;
        size += sizeof(u32);
 
@@ -1868,22 +1857,14 @@ static int process_cpu_topology(struct perf_file_section *section,
        }
 
        for (i = 0; i < (u32)cpu_nr; i++) {
-               ret = readn(fd, &nr, sizeof(nr));
-               if (ret != sizeof(nr))
+               if (do_read_u32(fd, ph, &nr))
                        goto free_cpu;
 
-               if (ph->needs_swap)
-                       nr = bswap_32(nr);
-
                ph->env.cpu[i].core_id = nr;
 
-               ret = readn(fd, &nr, sizeof(nr));
-               if (ret != sizeof(nr))
+               if (do_read_u32(fd, ph, &nr))
                        goto free_cpu;
 
-               if (ph->needs_swap)
-                       nr = bswap_32(nr);
-
                if (nr != (u32)-1 && nr > (u32)cpu_nr) {
                        pr_debug("socket_id number is too big."
                                 "You may need to upgrade the perf tool.\n");
@@ -1907,18 +1888,13 @@ static int process_numa_topology(struct perf_file_section *section __maybe_unuse
                                 void *data __maybe_unused)
 {
        struct numa_node *nodes, *n;
-       ssize_t ret;
        u32 nr, i;
        char *str;
 
        /* nr nodes */
-       ret = readn(fd, &nr, sizeof(nr));
-       if (ret != sizeof(nr))
+       if (do_read_u32(fd, ph, &nr))
                return -1;
 
-       if (ph->needs_swap)
-               nr = bswap_32(nr);
-
        nodes = zalloc(sizeof(*nodes) * nr);
        if (!nodes)
                return -ENOMEM;
@@ -1927,24 +1903,15 @@ static int process_numa_topology(struct perf_file_section *section __maybe_unuse
                n = &nodes[i];
 
                /* node number */
-               ret = readn(fd, &n->node, sizeof(u32));
-               if (ret != sizeof(n->node))
+               if (do_read_u32(fd, ph, &n->node))
                        goto error;
 
-               ret = readn(fd, &n->mem_total, sizeof(u64));
-               if (ret != sizeof(u64))
+               if (do_read_u64(fd, ph, &n->mem_total))
                        goto error;
 
-               ret = readn(fd, &n->mem_free, sizeof(u64));
-               if (ret != sizeof(u64))
+               if (do_read_u64(fd, ph, &n->mem_free))
                        goto error;
 
-               if (ph->needs_swap) {
-                       n->node      = bswap_32(n->node);
-                       n->mem_total = bswap_64(n->mem_total);
-                       n->mem_free  = bswap_64(n->mem_free);
-               }
-
                str = do_read_string(fd, ph);
                if (!str)
                        goto error;
@@ -1968,19 +1935,14 @@ static int process_pmu_mappings(struct perf_file_section *section __maybe_unused
                                struct perf_header *ph, int fd,
                                void *data __maybe_unused)
 {
-       ssize_t ret;
        char *name;
        u32 pmu_num;
        u32 type;
        struct strbuf sb;
 
-       ret = readn(fd, &pmu_num, sizeof(pmu_num));
-       if (ret != sizeof(pmu_num))
+       if (do_read_u32(fd, ph, &pmu_num))
                return -1;
 
-       if (ph->needs_swap)
-               pmu_num = bswap_32(pmu_num);
-
        if (!pmu_num) {
                pr_debug("pmu mappings not available\n");
                return 0;
@@ -1991,10 +1953,8 @@ static int process_pmu_mappings(struct perf_file_section *section __maybe_unused
                return -1;
 
        while (pmu_num) {
-               if (readn(fd, &type, sizeof(type)) != sizeof(type))
+               if (do_read_u32(fd, ph, &type))
                        goto error;
-               if (ph->needs_swap)
-                       type = bswap_32(type);
 
                name = do_read_string(fd, ph);
                if (!name)
@@ -2034,12 +1994,9 @@ static int process_group_desc(struct perf_file_section *section __maybe_unused,
                u32 nr_members;
        } *desc;
 
-       if (readn(fd, &nr_groups, sizeof(nr_groups)) != sizeof(nr_groups))
+       if (do_read_u32(fd, ph, &nr_groups))
                return -1;
 
-       if (ph->needs_swap)
-               nr_groups = bswap_32(nr_groups);
-
        ph->env.nr_groups = nr_groups;
        if (!nr_groups) {
                pr_debug("group desc not available\n");
@@ -2055,16 +2012,11 @@ static int process_group_desc(struct perf_file_section *section __maybe_unused,
                if (!desc[i].name)
                        goto out_free;
 
-               if (readn(fd, &desc[i].leader_idx, sizeof(u32)) != sizeof(u32))
+               if (do_read_u32(fd, ph, &desc[i].leader_idx))
                        goto out_free;
 
-               if (readn(fd, &desc[i].nr_members, sizeof(u32)) != sizeof(u32))
+               if (do_read_u32(fd, ph, &desc[i].nr_members))
                        goto out_free;
-
-               if (ph->needs_swap) {
-                       desc[i].leader_idx = bswap_32(desc[i].leader_idx);
-                       desc[i].nr_members = bswap_32(desc[i].nr_members);
-               }
        }
 
        /*
@@ -2137,21 +2089,15 @@ static int process_cache(struct perf_file_section *section __maybe_unused,
        struct cpu_cache_level *caches;
        u32 cnt, i, version;
 
-       if (readn(fd, &version, sizeof(version)) != sizeof(version))
+       if (do_read_u32(fd, ph, &version))
                return -1;
 
-       if (ph->needs_swap)
-               version = bswap_32(version);
-
        if (version != 1)
                return -1;
 
-       if (readn(fd, &cnt, sizeof(cnt)) != sizeof(cnt))
+       if (do_read_u32(fd, ph, &cnt))
                return -1;
 
-       if (ph->needs_swap)
-               cnt = bswap_32(cnt);
-
        caches = zalloc(sizeof(*caches) * cnt);
        if (!caches)
                return -1;
@@ -2160,10 +2106,8 @@ static int process_cache(struct perf_file_section *section __maybe_unused,
                struct cpu_cache_level c;
 
                #define _R(v)                                           \
-                       if (readn(fd, &c.v, sizeof(u32)) != sizeof(u32))\
+                       if (do_read_u32(fd, ph, &c.v))\
                                goto out_free_caches;                   \
-                       if (ph->needs_swap)                             \
-                               c.v = bswap_32(c.v);                    \
 
                _R(level)
                _R(line_size)