systemd/journald-advice-about-use-of-memory.patch

139 lines
5.3 KiB
Diff

From: werner@suse.de
Upstream: marked as openSUSE-specific fix originally, but may well
worth be to be sent upstream.
Original description:
(none)
Notes [jengelh@inai.de]:
MAP_NONBLOCK is documented (mmap(2) in man-pages-3.69+) to render
MAP_POPULATE ineffective. Why do we have it?
What is the rationale for MAP_STACK?
---
src/journal/catalog.c | 12 +++++++++++-
src/journal/journal-authenticate.c | 7 +++++--
src/journal/journald-kmsg.c | 3 ++-
src/journal/mmap-cache.c | 16 +++++++++++++++-
4 files changed, 33 insertions(+), 5 deletions(-)
Index: systemd-221/src/journal/catalog.c
===================================================================
--- systemd-221.orig/src/journal/catalog.c
+++ systemd-221/src/journal/catalog.c
@@ -469,6 +469,10 @@ finish:
static int open_mmap(const char *database, int *_fd, struct stat *_st, void **_p) {
const CatalogHeader *h;
+ static const unsigned int advice[] =
+ {MADV_WILLNEED, MADV_SEQUENTIAL, MADV_DONTDUMP, MADV_DONTFORK};
+ unsigned int n;
+ size_t psize;
int fd;
void *p;
struct stat st;
@@ -491,12 +495,18 @@ static int open_mmap(const char *databas
return -EINVAL;
}
- p = mmap(NULL, PAGE_ALIGN(st.st_size), PROT_READ, MAP_SHARED, fd, 0);
+ psize = PAGE_ALIGN(st.st_size);
+ p = mmap(NULL, psize, PROT_READ, MAP_SHARED | MAP_POPULATE |
+ MAP_NONBLOCK, fd, 0);
if (p == MAP_FAILED) {
safe_close(fd);
return -errno;
}
+ for (n = 0; n < sizeof(advice) / sizeof(*advice); ++n)
+ if (madvise(p, psize, advice[n]) < 0)
+ log_warning("Failed to give advice about use of memory: %m");
+
h = p;
if (memcmp(h->signature, CATALOG_SIGNATURE, sizeof(h->signature)) != 0 ||
le64toh(h->header_size) < sizeof(CatalogHeader) ||
Index: systemd-221/src/journal/journal-authenticate.c
===================================================================
--- systemd-221.orig/src/journal/journal-authenticate.c
+++ systemd-221/src/journal/journal-authenticate.c
@@ -355,7 +355,8 @@ int journal_file_fss_load(JournalFile *f
goto finish;
}
- m = mmap(NULL, PAGE_ALIGN(sizeof(FSSHeader)), PROT_READ, MAP_SHARED, fd, 0);
+ m = mmap(NULL, PAGE_ALIGN(sizeof(FSSHeader)), PROT_READ,
+ MAP_SHARED | MAP_STACK, fd, 0);
if (m == MAP_FAILED) {
m = NULL;
r = -errno;
@@ -399,7 +400,9 @@ int journal_file_fss_load(JournalFile *f
goto finish;
}
- f->fss_file = mmap(NULL, PAGE_ALIGN(f->fss_file_size), PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
+ f->fss_file = mmap(NULL, PAGE_ALIGN(f->fss_file_size),
+ PROT_READ | PROT_WRITE, MAP_SHARED | MAP_STACK,
+ fd, 0);
if (f->fss_file == MAP_FAILED) {
f->fss_file = NULL;
r = -errno;
Index: systemd-221/src/journal/journald-kmsg.c
===================================================================
--- systemd-221.orig/src/journal/journald-kmsg.c
+++ systemd-221/src/journal/journald-kmsg.c
@@ -454,7 +454,8 @@ int server_open_kernel_seqnum(Server *s)
return 0;
}
- p = mmap(NULL, sizeof(uint64_t), PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
+ p = mmap(NULL, sizeof(uint64_t), PROT_READ | PROT_WRITE,
+ MAP_SHARED | MAP_STACK, fd, 0);
if (p == MAP_FAILED) {
log_error_errno(errno, "Failed to map sequential number file, ignoring: %m");
return 0;
Index: systemd-221/src/journal/mmap-cache.c
===================================================================
--- systemd-221.orig/src/journal/mmap-cache.c
+++ systemd-221/src/journal/mmap-cache.c
@@ -466,11 +466,14 @@ static int add_mmap(
struct stat *st,
void **ret) {
+ static const unsigned int advice[] =
+ {MADV_WILLNEED, MADV_SEQUENTIAL, MADV_DONTDUMP, MADV_DONTFORK};
uint64_t woffset, wsize;
Context *c;
FileDescriptor *f;
Window *w;
void *d;
+ unsigned int n;
int r;
assert(m);
@@ -509,7 +512,8 @@ static int add_mmap(
}
for (;;) {
- d = mmap(NULL, wsize, prot, MAP_SHARED, fd, woffset);
+ d = mmap(NULL, wsize, prot, MAP_SHARED | MAP_POPULATE |
+ MAP_NONBLOCK, fd, woffset);
if (d != MAP_FAILED)
break;
if (errno != ENOMEM)
@@ -522,6 +526,16 @@ static int add_mmap(
return -ENOMEM;
}
+ for (n = 0; n < sizeof(advice) / sizeof(*advice); ++n) {
+ if (advice[n] == MADV_DONTFORK) {
+ int flags = fcntl(fd, F_GETFD);
+ if (flags < 0 || !(flags & FD_CLOEXEC))
+ continue;
+ }
+ if (madvise(d, wsize, advice[n]) < 0)
+ log_warning("Failed to give advice about use of memory: %m");
+ }
+
c = context_add(m, context);
if (!c)
goto outofmem;