[pulseaudio-commits] r1745 - in /branches/lennart/src/pulsecore: core-util.c core-util.h

[svnmailer-noreply at 0pointer.de]

Author: lennart
Date: Sun Sep  2 22:36:32 2007
New Revision: 1745

URL: http://0pointer.de/cgi-bin/viewcvs.cgi?rev=3D1745&root=3Dpulseaudio&vi=
ew=3Drev
Log:
add new pa_will_need() API for paging in memory

Modified:
    branches/lennart/src/pulsecore/core-util.c
    branches/lennart/src/pulsecore/core-util.h

Modified: branches/lennart/src/pulsecore/core-util.c
URL: http://0pointer.de/cgi-bin/viewcvs.cgi/branches/lennart/src/pulsecore/=
core-util.c?rev=3D1745&root=3Dpulseaudio&r1=3D1744&r2=3D1745&view=3Ddiff
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
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--- branches/lennart/src/pulsecore/core-util.c (original)
+++ branches/lennart/src/pulsecore/core-util.c Sun Sep  2 22:36:32 2007
@@ -54,6 +54,10 @@
 #include <sys/capability.h>
 #endif
 =

+#ifdef HAVE_SYS_MMAN_H
+#include <sys/mman.h>
+#endif
+
 #ifdef HAVE_PTHREAD
 #include <pthread.h>
 #endif
@@ -1241,3 +1245,69 @@
     pa_xfree(cwd);
     return r;
 }
+
+void *pa_will_need(const void *p, size_t l) {
+#ifdef RLIMIT_MEMLOCK
+    struct rlimit rlim;
+#endif
+    const void *a;
+    size_t size;
+    int r;
+    size_t bs;
+    =

+    pa_assert(p);
+    pa_assert(l > 0);
+
+    a =3D PA_PAGE_ALIGN_PTR(p);
+    size =3D (const uint8_t*) p + l - (const uint8_t*) a;
+    =

+    if ((r =3D posix_madvise((void*) a, size, POSIX_MADV_WILLNEED)) =3D=3D=
 0) {
+        pa_log_debug("posix_madvise() worked fine!");
+        return (void*) p;
+    }
+    =

+    /* Most likely the memory was not mmap()ed from a file and thus
+     * madvise() didn't work, so let's misuse mlock() do page this
+     * stuff back into RAM. Yeah, let's fuck with the MM!  It's so
+     * inviting, the man page of mlock() tells us: "All pages that
+     * contain a part of the specified address range are guaranteed to
+     * be resident in RAM when the call returns successfully." */
+        =

+#ifdef RLIMIT_MEMLOCK
+    pa_assert_se(getrlimit(RLIMIT_MEMLOCK, &rlim) =3D=3D 0);
+    =

+    if (rlim.rlim_cur < PA_PAGE_SIZE) {
+        pa_log_debug("posix_madvise() failed, resource limits don't allow =
mlock(), can't page in data: %s", pa_cstrerror(r));
+        return (void*) p;
+    }
+    =

+    bs =3D PA_PAGE_ALIGN(rlim.rlim_cur);
+#else
+    bs =3D PA_PAGE_SIZE*4;
+#endif
+        =

+    pa_log_debug("posix_madvise() failed, trying mlock(): %s", pa_cstrerro=
r(r));
+
+    while (size > 0 && bs > 0) {
+
+        if (bs > size)
+            bs =3D size;
+        =

+        if (mlock(a, bs) < 0) {
+            bs =3D PA_PAGE_ALIGN(bs / 2);
+            continue;
+        }
+
+        pa_assert_se(munlock(a, bs) =3D=3D 0);
+
+        a =3D (const uint8_t*) a + bs;
+        size -=3D bs;
+    }
+
+    if (bs <=3D 0)
+        pa_log_debug("mlock() failed too, giving up: %s", pa_cstrerror(err=
no));
+    else
+        pa_log_debug("mlock() worked fine!");
+
+    return (void*) p;
+}

Modified: branches/lennart/src/pulsecore/core-util.h
URL: http://0pointer.de/cgi-bin/viewcvs.cgi/branches/lennart/src/pulsecore/=
core-util.h?rev=3D1745&root=3Dpulseaudio&r1=3D1744&r2=3D1745&view=3Ddiff
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
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--- branches/lennart/src/pulsecore/core-util.h (original)
+++ branches/lennart/src/pulsecore/core-util.h Sun Sep  2 22:36:32 2007
@@ -100,6 +100,8 @@
 char *pa_getcwd(void);
 char *pa_make_path_absolute(const char *p);
 =

+void *pa_will_need(const void *p, size_t l);
+
 static inline int pa_is_power_of_two(unsigned n) {
     return !(n & (n - 1));
 }